Smile design n/certified fixed orthodontic courses by Indian dental academy

INTRODUCTION
In our modern competitive society, a pleasing appearance often means the
difference between success and failure in both our personal and professional
lives. Scottish physiologist Charles bell (1774-1842)was quoted as remarking
that the thought is to the word that the feeling is to the facial expression. He
pointed out in 1806 that a smile could convey a thousand different meanings ,
yet it is the most easily recognized expression. And because the mouth is one
of the focal points of the face , it should come as no surprise that the smile
plays a major role in how we perceive ourselves, as well as in the impressions
we make on the people around us.
A charming smile can open doors and knock down barriers that stand between
you and a fuller , richer life . An attractive or pleasing smile clearly enhances
the acceptance of the individual in the society where he belongs and the
character of the smile influences to the great extent the attractiveness and the
personality of the individual.
Basically the smile is dependant on the musculature and the presence of the
teeth. But every person is not fortunate enough to have a beautiful smile . The
answer to the above problem is the esthetic dentistry which has developed leaps
and bounds with the latest technologies and materials. Prosthodontist is
probably the best person to identify the quality of smile. Further he is also able
to change the quality of smile with the recently available innovative techniques
and the state of art restorative materials and to plan restorations, to harmonize
with the smile.
CLASSIFICATION OF SMILE (Solomon E.G.R.)
1)Depending on the nature of labial mucous
membrane
a) papilla smile
b) Gingival smile
c) Mucosa smile
2) Dependant on the lip component
a) Straight smile
b) Convex smile
c) Concave smile
Definitions:Glossary
of
Prosthodontic
terms.
January
1999.Esthetics1.
Pertaining to the study of beauty and the sense of
beautiful. Descriptive of a specific creation that results from such study;
objectifies beauty and attractiveness and elicit pleasure. 2.
Pertaining to
sensation. Esthetic reshaping
Modification of the surfaces of teeth to
improve appearance Esthetics (adj. 1798) 1.
The branch of philosophy
dealing with beauty. In dentistry, the theory and philosophy that deal with
beauty and beautiful, esp. with respect to the appearance of a dental
restorations, as achieved through its from and or color. Those subjective and

objective elements and principles underlying the beauty and attractiveness of
an object, design or principle.
Dental Esthetics
The application of the principles of esthetics to the natural
or artificial teeth and restorations. (GPT 1999)
Esthetic Dentistry
can be defined as the art and science of dentistry applied to create or
enhance beauty of an individual within functional and physiological
limits.(Ratnadeep Patil)
Cosmetic dentistry is application of the principles of esthetics and certain
illusionary principles, performed to signify or enhance beauty of an individual
to suit the role he has to play in his day-to-day life or otherwise. (Ratnadeep
Patil)
Smile designing is a process whereby the complete oral hard and soft tissues
are studied and evaluated and certain changes are brought about which will
have a positive influence on the overall esthetics of the face. These changes are
governed by the principles of esthetic dentistry. Hence, a good smile design
would naturally and effortlessly blend with the rest of the face to provide an
esthetic and functional complex
“ A well designed smile is a product of consolidated efforts accomplished by
accurate diagnosis, methodical treatment planning, use of advanced materials
and contemporary techniques rendered by the skilled dentist”.
Physical attributes of the elements of the dento-facial composition
The artistic parameters to be considered for essential beauty and those which
are subtly present in natural beauty form the fundamental principles of
esthetics. Understanding these artistic parameters of beauty and co-relaing
them to the dento-facial complex will enable the dentist to appropriately scale
esthetics in any dento-facial composition.
Composition means the act of combining elements or parts to form a whole.
There are various physical attributes of the elements of a composition that
impart the esthetic value. The various physical attributes of the elements of a
composition are:
Contrast:
It is that factor which makes the various elements of a composition visible. The
eye can differentiate the parts of an object due contrast of colors,lines, patterns,
textures, etc. The relationship between the different parts of the face (facial),
the teeth and the gums (dental) made visible by contrast constitutes the dentofacial composition.
Unity or oneness: “It gives different parts of the composition the effect of a
whole”. Unity can either be static, when repeated shapes or designs are seen as
in inanimate things, like the composition of crystals; or dynamic and changing
as in living beings. Unity between different parts of the face, and teeth is
essential to give the effect of oneness or wholeness to the dento-facial
composition (Fig.2-1b)

Cohesive and segregate forces: Any element which tends to unify a
composition is a cohesive force. Segregative forces are those elements which
break the monotony of the composition. Naturalness has combination of
cohesive and segregative forces. A proper mix of segregative and cohesive
forces adds variety to the composition making it more dynamic and
interestingSymmetry: It is the regularity of arrangement of forms either from
either from left to right as in horizontal symmetry, or from a central point to
either side like a mirror image as in radiating symmetry. The horizontal
symmetry looks repetitive and uninteresting while the radiating symmetry
looks dynamic and interesting. In a dento-facial composition radiating
symmetry of the teeth is more esthetically appealing and is associated with
youthfulness while horizontal symmetry is less appealing and is associated with
aging.Proportion: To be able to give a certain mathematical representation of
beauty for numerically expressing the relationship of the various units that
combine to make a composition, the term proportion is used.
The relationship of the various units which are different from each other in a
composition but are associated with each other through a certain repetitive
mathematical factor is the repeated ratio.
The proportion between the various elements of a harmonious composition, in
which the cohesive and segregative forces are equally balanced,and whichhas
its various units in an esthetically appealing respective proportion to each other
is the golden proportion
Dominance: It exists when a strong centralized structure is surrounded by welldemarcated, characterized structures. In a dento-facial composition it creates
immaculate unity leading to a harmonious composition. The absence of
dominance makes the composition weak. Color, shape and size are the factors
which can control dominance).
Balance: It is achieved when there is an exact equilibrium between the forces
present on either side of the fulcrum in a composition. In dentistry this implies
the balance of the elements in relation to the midline. If any elements are
imbalance on one side then, to create a visual balance either these elements are
moved towards the midline or are counter-balanced with opposite elements to
regain the balance. In balance the weight of the elements far away from the
fulcrum grows in importance
Visual tension is the tension brought about by the presence of certain elements
that cause an imbalance in the given composition. If the presence of these
factors is closer to the fulcrum, the effect of the tension into the fulcrum,the
effective the tension induced is more magnified as against their presence
further from the fulcrum. A distally inclined lateral incisor on one side is
compensated by a more mesial inclination of the first premolar on the opposite
side to reduce the effective visual tension. These variations are naturally found
in dentitions explaining the reason why sometimes irregularities in inclinations
still produce pleasant smiles.

The esthetic orientation of the dental composition with the entire facial
composition can be achieved by taking into consideration the references, smile
elements, proportions and symmetry. These are the factors of esthetic
compositions and they help the dentist in determining tooth display, size,
arrangement and alignment during the diagnosis and treatment phase.
The dento-facial frame constitutes the teeth and gingiva related to the lips and
then to the entire face. The oral frame is determined by the anatomy and
mobility of the tissues when in function surrounding the teeth and gingiva .The
exposed portion of the oral elements i.e. teeth and gums within the oral frame
during a smile is called the smile window.
.
The anatomical elements of the face and the biological elements that include
the functional and phonetic elements, provide the reference frames, guidelines
and points. These elements help the dentist to achieve a general sense of
orientation and diagnosis.
References can be classified as horizontal references, vertical references,
sagital references and phonetic references.
Horizontal references: The horizontal perspective of the face is provided by
the interpupillary line the commissural line.
The inter-pupillary line helps to evaluate the orientation of the incisal
plane, the gingival margins and the maxilla. An imaginary horizontal line
through the incisal plane and the gingival margins should be visibly parallel to
the inter-pupillary line. This helps to diagnose any asymmetry in the tooth
position or gingival location. When an imaginary line is drawn across the
gingival margins, it may not be parallel to the inter-pupillary line indicating a
certain degree of canting of the maxilla.
Certain amount of canting of maxilla is considered normal and in such cases
mild correction of the gingival margins can achieve a pleasing symmetry
Severe canting may require an inter-disciplinary approach involving surgical
repositioning of the maxilla.
Vertical references: The facial midline serves to evaluate the location and axis
of the dental midline and the medio-lateral discrepancies in tooth position.The
inter-pupillary line and the facial midline emphasize the „T‟ effect in a pleasing
face. The dental midline, if perpendicular to the inter-pupillary line and
coinciding with the bridge of the nose and the philtrum, produces an attractive
orientation of the smile.
Axial inclination is the direction of the anterior teeth in relation to the central
midline and becomes progressively more pronounced from the central incisor
to the canine. There is a definite mesial inclination to all the anterior teeth
related to the midline. The axes of the premolars and the first molar on either
side also show mesial inclination in relation to the midline.
The perception of tooth inclination can be viewed from the frontal aspect
around the central vertical midline, which acts like a fulcrum around which
axial inclination of teeth on either side exhibit a phenomenon of balance of
lines Natural smiles show a deviation from these standard axial inclination.

Deviations in axial inclination cause a visual tension when beyond the point of
equilibrium
Sagittal references: Soft tissue analysis at a standardized position helps in
studying the profile of an individual. The contours of the upper and lower lip
support is determined by the position of the anterior teeth and can be used as a
guide for the placement of teeth when planning restorations. The lip protrusion,
the amount of prominence of chin, recession or prominence of the nose and its
degree, all help in profile analysis for diagnosis and treatment planing.
The E-line or esthetic line is an imaginary line connecting the tip of the nose
to the most prominent portion of the chin on the profile, ideally the upper lip is
1-2 mm behind and the lower lip 2-3mm behind the E-line. Any change in the
position of the E-line indicates the abnormality in the upper or lower lip
position.
The main support of the upper lip is contributed by the gingival two thirds of
the maxillary central incisors rather than the incisal one third According to
studies by Maritato and Douglas the lip support is a better guide of tooth
position than of incisal edge position.
The relationship of the maxillary incisl edges to the lower lip is a guide for the
placement of the incisal edge position and length. The pronunciation of the „F‟
and „V‟consonants helps determine the position of the incisal edges. On
pronouncing „F‟ and „V‟ the incisal edges should make a definite contact at the
inner vermilion border of the lower lip Thus the position of the incisal third of
the maxillary central incisor can be determind.

Phonetic references: Phonetics play a part in determining maxillary central
incisor design and position.
„F‟ and „V‟ sounds are used to determine the tilt of the incisal third of the
maxillary central incisors and their length. The „M‟ sound is used to achieve
relaxed rest position and repeated at slow intervals can help evaluate the incisal
display at rest position „S‟ or „Z‟ sounds determine the vertical dimension of
speech.. Its pronunciation makes the maxillary and the mandibular anterior
teeth come in near contact and determine the anterior speaking space The
amount of posterior speaking space varies with the amount of mandibular
protrusion necessary to bring the anterior teeth in near contact for the „S‟
sound.
Smile elements: The extent of the smile is outlined by the curvature of the
upper and lower lip and the position of the angle of the mouth, and it
determines the degree of exposure, both in the anterior and posterior teeth,
gingiva as well as the width of the buccal corridor
Smiles can be classified as passive, active (moderate) and laugh. In a passive
smile the lips are parted slightly away from the rest position expressing
content, passion, desire, surprise, etc. In an active smile the lips move to a
significant extent away from the rest position displaying more teeth and even
gums, expressing joy, welcome, happiness, etc. Laugh is an instant fluctuation

from an active smile position where the facial muscles instantly act leading to
maximum exposure of the teeth and gums. Humorous and funny situations
usually lead to such an expression.
Lip and lip lines: The length, the curvature and the shape of the lips
significantly influence the amount of tooth exposure during rest and in
function.
A prominent tooth display is associated with a youthful smile and most patients
would like to seek the benefit of the same. Some researchers demonstrated that
the average maxillary incisor display with the lips at rest is 1.91mm in men and
3.40 mm in Women Patient‟s with short upper lips and younger patients
generally display more maxillary tooth structure which may be up to 3.65mm.
Upper lip line helps to evaluate the length of the maxillary incisor exposed at
rest and during smile and the vertical position of the gingival margins during
smile.
The upper lip line can be classified as low, medium or high depending upon the
amount of tooth or gingival display that is available at rest of during a moderate
smile. The gingival margins may be displayed in high lip line cases. The most
apical position of the gingiva over the facial aspect of the maxillary central
incisor and canine is slightly distal to the long axis of the tooth while in the
maxillary lateral incisor it is at the long axis of the tooth. This is called the
gingival zenithWhenever a patient displays the gingival margins easily on
smiling or speaking, a definite pattern of the gingival display can be recorded.
This pattern can be either esthetic or unesthetic A smile can be termed “toothy”
if more than 6mm of incisal display is seen at rest position or “gummy” if
more than 3mm of gingival tissues are displayed in moderate smile)
Lower lip line helps to evaluate the buccolingual position of the incisal edge of
the maxillary incisors and the curvature of the incisal planeSmile line: It is an
imaginary line passing through the incisal edges of the upper anterior teeth.
The smile line usually coincides or runs parallel to the inner vermilion border
of the lower lip. In a youthful smile the incisal edges of the central incisors and
canines are aligned on a convexity and are linger than the lateral incisors,
incisal embrasures gradually deepen from central incisor to the canine, giving
the appearance of the wings of a gull. Thus the incisal plane is said to have a
gull-wing apperance When the incisal edges of the central incisors and canines
are aligned on a convexity the incisal plane is convex. Reduced incisal
embrsures and leveling of the gull-wing effect as in a straight smile line is
associated with aging.
Negative space: Negative space is a dark space appearing between the jaws and
the mouth opening either at the corner of the mouth of around the buccal aspect
of the posterior teeth during active smile and laugh.The lateral negative space
exists between the labial surface of maxillary teeth and the corner of the mouth
while the buccal negative spaces appear in the buccal vestibule on either side of
the buccal aspect of posterior teethObliteration of these essential spaces by
dental elements like bulky canines, wide arches or over-contoured restorations
can lead to an unattractive smile.

Excessive negative space seen in cases of missing premolars orA palatally
placed posteriors and a constricted arch also appear unesthetic.
Progressive abating in a dental composition: When similar structures are
aligned in an arch form one after the other, they appear to progressively abate
in size from the nearest to the farthest. This gives an illusion of depth.
The essential requirement of the front to back progression in dental
composition is the alignment of the contour of the labial and surface at the
incisal third, middle third and the gingival third of successive teeth in the arch.
The incisal mesio-buccal inclines should be well aligned to give a smooth
progression from tooth to tooth. The buccal and lateral negative space
progressively reduces the illumination on teeth to enhance the front to back
abating effect. The presence of poorly shaped teeth, differences in axial
inclinations, tooth length discrepancies, discolorations, gingival disharmonies
etc. can lead to a visual tension resulting in a disruption of the front to back
progression.
Proportion
When mathematics is applied to the study of ideal tooth form, a
numerical relationship is established within a single tooth form (ideal
proportion) and also between a series of teeth in the arch (relative proportion).
The position of the tooth in the arch, the relationship between the width, the
length and the face of the tooth can also be numerically established in relation
with certain anatomic landmarks.
Gold Proportion is expressed in numerical form and applied by classical
mathematicians such as Euclid and Pythagoras in pursuit of universal divine
harmony and balance. It has been applied to a lot of ancient Greek and
Egyptian architecture and may be expressed as the ratio 1.618:1.
If the ratio is applied to the smile made up of the central, lateral incisor
and the mesial half of the canine, it shows that the central incisor is 62% wider
than the lateral incisor which in turn is 62% wider than the visible portion of
the canine which is the mesial half, when viewed from the front.
Application of sizing the central incisors from certain facial measurements is
known as the 1 to 16 theory, whereby the height of an ideal maxillary central
incisor from the incisal edge to the gingival crest is 1/16th of the distance from
the inferior border of the chin to the inter papillary line. The same tooth width
can be measured from the mesial to distal contact areas and is 1/16th of the
distance measured from either zygomatic prominence through an imaginary
facial midline.
Once the size for the central incisor is determined it is essential to design its
outline form. The facial harmony method can be applied to relate the tooth
form to the facial form. Various facial shapes are identified and descriptions
such as avoid, square, tapered and combinations of these are used The same
shape when inverted can be applied to the central incisor design. This shape
acts as guideline for the outline forms of other maxillary teeth.
In an attempt to determine the original anterior tooth placement on the ridge,
the position of the incisive papilla is considered as an important land mark as it
position does not alter even after bone resportion of the anterior ridge. The

distance between the posterior border of the papilla to the outer labial surface
of the central incisor averages to about 12.5mm with a variation of
approximately 3.8mm. The end of the first palatal ruga is located 1.5 mm to
2mmm from the lingual surface of the canine. Many dentists have also
recorded the averages distance between the base of the sulcus and the tip of the
maxillary incisor. This distance is measured 22mm. This helps the dentist to
determine the tooth position in the vertical plane.
Symmetry
For harmony, certain symmetries are essential while certain asymmetries
are acceptable. Harmonious facial features should be more symmetrical close
to the facial mid line and can be more asymmetrical away from the facial
midline.
Pleasing Smile
A naturally attractive smile that evokes a feeling of beauty or harmony
and complements the personality of the bearer is termed as a pleasing smile.
The natural pleasing smile may not necessarily comply with all rules of
symmetry or golden proportion or may not exhibit perfect balance without
irregularity of shape. However, the composition is esthetically appealing with
unity within its various elements.
Smile Dominance : Different facial features stand out differently in the eyes of
every beholder. In certain cases, the most predominantly striking features of a
face is the smile; these are the “Dominant Smiles”.
The distinguishing characteristics observed in people with pleasant
smile dominance that can be used as a guideline for creating the same are :

The maxillary central incisors exhibit a strong presence by their size
and form reflecting the personality of the individual.

The maxillary lateral incisors and the canines complement the cement
incisor in terms of proper shape and form.
Although numerically all proportions of the anterior teeth do not follow the rule
of golden proportion, the teeth are so placed that they appear in suitable
proportions with each other.

Smile recurring ratios are observed in the teeth from the central incisor
to the premolar.

Well co-ordinated movements of the lips with the other peri-oral
musculature and corresponding harmonious facial expressions, contribute to
the pleasant face during smile.

The complexion and texture on the face contrast with the lip color,
gingival and the teeth leading to a distinct demarcation between the oral and
the facial frame.
PERCEPTUAL ASPECTS – THE ART OF ILLUSION
Illusion is a figment of imagination where a perception of an object is
created.
Fundamental and Principles

The art of creating illusions consists of changing perception, to cause an
object to appear different from what it actually is. Teeth can be made to appear
smaller, larger, wider, narrower, shorter, longer, younger, older, masculine or
feminine.
One being subjected to light the most fundamental objects exhibits two
dimensions, that is, length and width. True natural light is multi-directional
and on striking the surface of the object, also reveals texture and shadows, this
adds the third life like dimension of depth.
Illusion works on two basic principles which are the principle of illumination
and the principle of light. The most important of these is the perception that
light approaches and dark recedes. This is termed as the „Principle of
Illumination”. The second artistic predilection of great importance in dentistry
is the use of horizontal and vertical lines and ridges. Horizontal lines make the
object appear wider and vertical lines make the object appear longer. This is
termed as the “Principle of Line”.
The artistic predilection exhibited in the principle of illumination can be
maintained to change the size, shape and the overall form of the tooth through
illusions.
Law of the face. The face of a tooth is that area on the facial surface on both
anterior and posterior teeth, that is bound by the transitional line angles as
viewed from the facial i.e. labial or buccal aspect. These transitional line
angles mark the transition from the facial surface to the mesial, distal, cervical
and incisal surfaces. The tooth surface slopes lingually in the mesial and distal
region while it slopes cervically from the line angles towards the root surface.
Whenever there is no transitional line angle demarcating the incisal portion of
the facial surface, the face is bound by the incisal edge or the occlusal tip.
Shadows created as light strikes the facial surface of the tooth begin at the
transitional line angles, these shadows delineate the boundaries of the facial
form. Thus the apparent face is that portion of the face that is visible to the
observer from any single view. When maxillary anterior teeth are viewed
from the front only the mesial half of the canine is visible however the entire
incisor face is visible.
The law of the face implies making dissimilar teeth appear similar by making
the apparent faces equal. The apparent face should be manipulated, not the
actual face. This is more important in the canines and the posteriors as the
„apparent face‟. The transitional line angles are relocated so that the apparent
faces look equal, however this results in dissimilar areas outside the transitional
line angles.
Similar faces produced attract light and appear high lighted while the
dissimilar areas that are in a shadow appear to recede.
When the transitional line angles cannot be repositioned on a restoration,
then the portion of the tooth can be stained darker to create an illusion that the
transition line angle has been moved.
Cosmetic contouring

Cosmetic contouring by definition is the reshaping of natural teeth to
make them esthetically pleasing.
In natural dentitions, variations seen in tooth shape and size some times
violate the acceptable width to length ratios as well as the golden proportion.
Minor adjustments in contours to change the perception of these proportions
increases the esthetic acceptability to a great extent. It is indicated for giving a
pleasing appearance to fractured, chipped, extruded, malformed or over lapped
teeth
The procedure is contra indicated in hypersensitive teeth, teeth with thin or
defective enamel formation or large pulp chambers.
The upper lip line should be used as a reference to see how much tooth
is visible when the patient smiles. The lower lip line will help to create a
pleasing smile line. Tooth visibility with lips at rest, when the patient talks or
smiles should also be assessed. The dentist should view the patient in sitting
and standing positions
Procedure
The procedure involves minimum tooth reduction confined to enamel.
Changes on the tooth surface of the related tooth are carried out by working on
the transitional line angels, height of contour, incisal and facial embrasures and
adjusting incisal edge and angels. Finishing disks are used to open incisal
embrasures and the reshaped teeth are then thoroughly polished with a fine grit
diamond paste and application of fluoride gel or foam is recommended to
minimize any chances of postoperative sensitivity.
ESTHETIC DIAGNOSIS AND TREATMENT PLANNING
Total Smile Analysis
Total smile analysis is a cumulative inference analysis, drawn by interpreting
and integrating various analysis like a visual , space ,profile and computer
analysis after performing the preliminary analysis.
Space Analysis
It helps the dentist to gauge the amount of space available during the
treatment planning stage. The concept is to measure the widths of all the teeth
and to compare it with space present in the arch. This determines whether the
space available for restorations and natural teeth is less or more than required.
Disproportionate spaces may be due to discrepancies in jaw and tooth
size, malformed teeth, missing teeth, mal-aligned teeth etc. The space analysis
will provide a guideline or a frame work within which the esthetic dentist has
to plan each restoration.
Corrections of labio-lingual inclinations and rotations of the teeth by restorative
procedures will result in a change in the width space ratio due to the change of
angulation involved.
It may not be possible to match all teeth on either side of the midline due
to space or morphological constraints, but in order to preference they should be
matched as far as possible starting from the midline and proceeding towards the
canines. Symmetry and dominance of the central incisors being an important
element of the pleasing smile should not be compromised as far as possible.

For any changes proposed that may involve alterations in the width of
the anterior teeth, the law of golden proportion should be closed followed.
This enables the esthetic dentist to plan any space manipulations for the
restorations in terms of illusions, actual tooth positional changes such as
rotations overlaps, spacing etc.
Profile analysis
While examining the patients profile, the normal profile is referred to as
straight orthognathic. Any deviation from this should be recorded and
considered in treatment planning. Examination of the profile could be in the
antero-posterior plane or in the vertical plane.
If the profile is convex, the features seen include either a normal,
increased or decreased lower facial height, a lower lip trap depending on the
position of the lower anteriors and deep mento-labial groove.
If the profile is Concave the features include either an increase or decrease in
the lower facial height. This may also be associated with a habitual or a pseudo
Angle‟s Class III relationship.
Profile analysis helps in treatment planning of the cases that will require
skeletal correction in addition to the esthetic restorations for complete esthetic
success. This will ensure that the skeletal and non-skeletal aspects of the
treatment plan are segregated and treated for a comprehensive, successful
esthetic treatment.
Computer Analysis
Radiographs and photographic images have been used as an essential aid
in diagnosis, record keeping, communications and treatment planning.
Computer aided technology has broadened the scope of applicatiosn as well as
enhanced the utility of radiographs and photographs in the dental field. The
new intra-oral cameras with digital support and the radio-visiographs are
indispensable tools at the esthetic dental office. They give enlarged images of
the photographic and radiographic outputs on the screen, without the
involvement of any hard copies of photographs or radiographs, with multiple
magnifications, and at various angles, for the dentist as well as the patient to
assess and view the intra oral condition in a different perspective. This
becomes a handy tool for aiding correct diagnosis as well as a brilliant
motivational and communication tool. It is also now possible to do the various
facial and profile analysis on the computer screen without hard copies or
tracings. With different soft ware applications, the images can be altered for
the patient and dentist to appreciate the changes that Computer Analysis
Radiographs and photographic images have been used as an essential aid
in diagnosis, record keeping, communications and treatment planning.
Computer aided technology has broadened the scope of applicatiosn as well as
enhanced the utility of radiographs and photographs in the dental field. The
new intra-oral cameras with digital support and the radio-visiographs are
indispensable tools at the esthetic dental office
They give enlarged images of the photographic and radiographic outputs on the
screen, without the involvement of any hard copies of photographs or
radiographs, with multiple magnifications, and at various angles, for the dentist

as well as the patient to assess and view the intra oral condition in a different
perspective. the proposed treatment modalities may bring about without
actually carrying out the treatment.
In a particular case, esthetic enhancement with a change of arrangement, form,
shape or color can be demonstrated quickly. Thus computer analysis can be
used as a quick reference which can guide the future artistic creations that the
dentist may consider, However, the occlusal parameters cannot be addressed
without appropriate devices and hence the actual three dimensional aspect of)
Computer or voice activated data
Using voice activated technology , we can document our findings by
speaking into the microphone that are connected to a computer which has been
"trained" to recognise a limited vocabulary. The computer than stores the
infomation and even graphics( related to smile ) so that various procedures can
be discussed with the patient.
the change cannot be applied without error. Promising the patient results close
to what are seen through a computer analysis could lead to dis-satistication and
hence the dentist should consider other diagnostic means before designing
definitive treatment plans.
ROLE OF TECHNOLOGY IN CHANGING SMILE
New technology helps us to preview the end results.The following high tech
tools can be incorporated:
1) Extra oral video camera: It allows to have a detailed record of the patient's
face while moving and talking- a much more helpful tool than a still
photograph. It can record the patient in various moods and gestures and give us
the minute details the patient may be unaware of. This can be shown to the
patient with the help of computer imaging . Different smiles and profiles can be
applied to the patient's face and the patient can be given the opportunity to
choose the best smile design
) Intraoral video camera: It is an easy to use unit designed with reliability,
performance and image quality. Intra oral examination from every angle with
the smallest details can be viewed as close as 2mm. fron the tooth. With it we
can explain certain conditions and treatment options much more accurately
than with sketches, mirrors and X- rays.
Introral cameras can be integrated
with a computer imaging system to capture the detailed images of the patient's
oral cavity. These images can be modified according to the proposed treatment
options and shown to the patient. At the click of the mouse a particular tooth
can be elongated or widened , the effect of which can be shown to the patient
for his approval.
3) Computer or voice activated data
Using voice activated technology , we can document our findings by
speaking into the microphone that are connected to a computer which has been
"trained" to recognise a limited vocabulary. The computer than stores the
infomation and even graphics( related to smile ) so that various procedures can
be discussed with the patient.

) T- Scan and Digital Radiography
By using this scan , buccolingual width of the jaws as well as the
location of anatomic features such as the mandibular canal and the maxillary
sinus can be determined which is useful while placing an implant in the esthetic
position.
Now-a-days manufacturers promote digital radiography system and
video camera in one unit i.e. single hand piece which will be concenient for
use.
) CAD/CAM
With CAD/CAM ( Computer assisted design/ Conputer assisted
manufacture) technology we can design veneers and crowns to enhance smile
while the patient waits. The so called "mock- up" of a planned cosmetic
teatment also has been shown to be quite useful. It also allows clinician to
visualise the desired results and solve potential problems before providing
treatment to the patient.
) Lasers
The dental lasre uses a beam of light in place of scalpel to perform
delicate gum surgery and crown lengthening/ gingivectomy and gingivoplasty.
The advantages of this procedure are1) Controlled bleeding which provides dry operating field and hence
excellent visibility.
2) Reduced operating time and reduced post operative swelling, pain
and scarring.
Computer Imaging
It improves communication between the patient and the dentist by allowing
both to visualize , evaluate and agree on treatment. It allows to " see" various
looks before deciding upon treatment.
8) Computer Controlled Injection Technique
The P- ASA (Paltal approach anterior superior alveolar ) is a new block
injection technique that provides anaesthesia of the maxillary anterior teeth
from a single injection without numbness of the face , lips and the muscles of
facial expression. The injection can be administered in a comfortable and
consistent manner, using a computer controlled local anaesthetic delivery
system( the wand). This technique prevents distortion of the smile line and
enhances restorative procedures that use the lipline as an esthetic reference
element.
9) Abrasive Technology
In this technique , a jet air stream with micro abrasive particles is used to
remove the stained areas. It is painless, faster and does not require the use of
anesthesia. It can be used in any quadrant for any depth of decay without
damaging the healthy tooth structure. After the removal of the stained areas ,
the tooth structure can be built up with composite.
It is also useful during repairs to existing composite or porcelain
restorations because it roughens these surfaces allowing the reparative
materials to bond them more rapidly .

Occlusal considerations
The esthetic dentist has a major challenge in dealing with restorative
situations in the mouth where occlusal considerations are critical. Natural and
restored maxillary and mandibular teeth should have optimal functional contact
relationship resulting in the even distribution of load in static and dynamic
positions leading to minimal trauma of the teeth and supporting structures.
This requires a thorough understanding of the stomatognathic system which
comprises of the temporomandibular joint, the ligaments, related musculature
and the dentition and their coordinated three dimensional movements.
Concept of occlusion
A thorough knowledge of the various concepts of articulation
accompanied with application of the same is mandatory for successful
restorative rehabilitation.
The various concepts of occlusion are
Bilateral balanced occlusion
 Group function or unilateral balanced occlusion
Mutually protected occlusion
In large or complex rehabilitation‟s with fixed prosthesis, a sequential and
correct method of recording the jaw relations should be followed since any
error would be magnified in the final outcome. This would be detrimental to
the survival of the surrounding tissues and the restoration. The hinge axis of
the mandible should recorded with a kinematic face bow and transferred to an
adjustable. Arbitrary hinge axis face bow is useful for routine work and gives a
fairly accurate relationship (error of 5mm). Correct centric relationship and
protrusive and lateral inter occlusal records are made in rigid materials and the
articulators are adjusted accordingly. Correct incisal guidance is computed and
adjusted. This logical and systematic approach ensures minimum error.
Forces on the dentition
On the dentition it is influenced by several factors like position of the
teeth in the arch, masticatory dynamics, relationship with the opposing arch,
crown-root ratio, direction, duration, frequency and character of the forces
during functional mandibular movements and parafunctional habits.
The peri-oral musculature and the tongue exert a constant force on the teeth.
These forces are lighter and in a horizontal direction. Swallowing also exerts
forces on a continuous basis throughout the day. The peri-oral musculature and
the tongue exert a constant force on the teeth. These forces are lighter and in a
horizontal direction. Swallowing also exerts forces on a continuous basis
throughout the day. The heavier natural forces exerted on the teeth are during
mastication and are primarily directed perpendicular to the occlusal plane in the
posterior region. They are exerted infrequently and for a short duration during
the day.
In mutually protected occlusion, where there are no posterior contacts in
eccentric movements, fewer fibers of the temporalis and masseter muscles and
stimulated resulting in reduction of the forces applied on anterior teeth by two
thirds.

Research on implant prosthesis and crowns with cast cores on maxillary
incisors have shown permissible angle of up to 25° between the crown and root
for maintenance of adequate periodontal health.
Parafunctional movements Are identified as a cause for occlusal wear and
excessive forces. Parafunction can be related to local factors like malocclusion
or to systematic factors like cerebral palsy, epilepsy and can also be stress or
occupation related. Bruxism, clenching and parafunctional tongue thrust are the
important parafunctions which the dentist should consider in the treatment
planning stage.
Bruxism
Rehabilitation of these cases not only involves elimination of the
causative factors but establishment of correct anterior incisal guidance to
eliminate all posterior contacts during mandibular excursions.
Clenching : Is the force exerted from one occlusal surface to other without
movement. These forces are directed more vertically to the plane of occlusion
in the posterior region of the mouth. Fremitus is often found in the clenching
patient. This is vibratory type of a force felt with a finger kept in contact with
the facial aspect of a tooth while the patients taps the teeth together. It is
noticed clinically on many cervically eroded teeth, and if the occlusion is
carefully evaluated, it shows signs of excessive forces. This cervical defect is
called cervical abfraction. During the management of these cervical defects
occlusal adjustments need to be considered along with adhesive restorative
methods for a long term success.
Parafunctional tongue thrust :
Is an unnatural tongue force which can exert
an abnormal horizontal force on the anterior teeth.
Esthetic treatment planning and sequencing
Treatment sequencing is an integral part of treatment planning. It is a
phase wise distribution of treatment procedures which will be programmed or
charted considering periods of healing, patient convenience, inter disciplinary
treatment modalities and is the fundamental feature of a meticulous treatment
execution
Although some basic periodontal, pulpal and temporomandibular problems
would be addressed at the initial therapy stage, more definitive periodontal or
pulpal treatment may be necessary during the definitive therapy stage. Certain
cases involving endodontic posts or implants etc in the esthetic zone may pose
a challenge to the dentist in term of giving suitable interim restorations that will
not interfere with the healing process.
Mock up
Mock ups are made for diagnostic reasons during the treatment planning
phase as well as for reference purposes during the treatment phase. For the
cases requiring major esthetic correction involving many anterior teeth the
dentist can work on the space availability and allotment for every tooth on the
mock up even before proceeding for the tooth preparations.
A cosmetic preview with the help of composite resins is the easiest and fastest
procedure to help the dentist in diagnosis, treatment planning as well as
creating references during treatment execution

Composites can be put on the facial tooth surfaces including spaces or even the
gingiva to determine the change of position of teeth desired at the final
restorative phase. The dentist can show this preview of the patient and get his
opinion regarding tooth position, shade, shape etc.
The occlusion usually will restrict the restorative ease in many cases.
The lower incisors should be thoroughly examined and the contacts of the
palatal aspect of the upper teeth marked . The functional movements in the
mouth can also be checked at this time to determine any potential occlusal
Obstructions or difficulties that may arise at the time of treatment. Some
adjustment in the incisal edges of the mandibular incisors might be mandatory
before proceeding with esthetic correction for the maxillary anteriors.
In cases requiring reduction of tooth structure like in overlapping teeth,
a diagnostic wax-up would be more beneficial as the required reduction of the
teeth can be done on the study casts and suitable colored wax-up can be used to
visualize the end result and preparation design
In cases requiring closure of spaces and where crown lengthening could be
required to improve the width to length ratio of the final restorations, a
composite preview could be easily used. Before crown lengthening procedures
the extent of gingivectomy and the exact contour to be established on the facial
aspect contour to be established on the facial aspect is determined by the
location of the gingival zenith after the placement of the final restoration.
Hence a composite preview is used to determine the gingival contour and the
gingivectomy is performed according to this reference.
Once crown
lengthening is achieved and after sufficient healing period elapses, composite
or ceramic veneer is placed to give the final desired result.
COLOR
Dimensions of color
Color cannot be perceived without light, which is a form of electoromagnetic energy visible to the human eye. The visible spectrum of light lies in
a narrow band of 380nm to 760nm. It has the ability to stimulate the cells in
the retina which is interpreted by the brain, discerning the sense of color.
dimensions”. Hue, which is the name of the radiant energy, Chroma, which is
the saturation of the hue and value, which is the relative lightness or darkness
of the color. Since clinical color matching depends upon the ability of the
dentist to perceive the difference in the tooth shade guide comparison;
complete understanding of the color dimensions in critical.
The Munsell color order system best serves the needs of the dental
profession in its tempt to visualize and organize color.
Hue : In Munsell‟s words, “It is that quality by which wwe distinguish one
color family from anther”.
Generally there are six hue families. Violet, blue, green, yellow, orange
and red. For example, in the Vita shade guide there are four hues A, B, C and
denoting reddish brown, reddish yellow, grayish and reddish grey respectively.
Chroma :In Munsell‟s words, “it is the quality by which we distinguish a strong
color from a weak one. “Human teeth fall into the yellow to yellow red area of

the Munsell color order system. Pale colors have a low chroma whereas
intense colors have high chroma.
Value : Value or brilliance is the relative blackness or whiteness of color. On a
scale of black to white, white has “high value”, black a “Low value” and
Midway between black and white is the medium grey. Value is the only
dimension of color that can exist by itself.
Opacity and Translucency: As light strikes a surface, it is either totally
reflected, totally absorbed or a combination of both. Opaque objects reflect all
or most of the light that is incident on them whereas transparent objects
transmit all of the light that is incident on them.When part of the light incident
on an object is transmitted, while the rest is scattered, the property of the object
is known as translucency. It decreases with increasing scattering within the
materials.
Translucency, in effect, is the three dimensional spatial relationship or
representation of value. Highly translucent teeth tend to be lower in value,
since they allow light to transmit through the teeth, while opaque teeth have
higher value.
There might be inter tooth as well as intra tooth differences in the
translucency. Its extend can vary according to the age of the patient due to the
degenerative and reparative changes in the enamel and dentin. To mimic
natural teeth the effective use of restorative materials should largely depend
upon this translucent effect.
Mechanism
The change in color perception of two objects under different light
sources is called metamerism. For example , a shade guide tooth matches the
natural tooth under incandescent light but not under fluorescent light. This can
be attributed to the difference in the radiant energy of two different
wavelengths of light.
The standardization of lighting condition during hade matching
diminishes the effect of metamerism.
Fluorescence
The emission of light by an object at a different wavelength from that of
the incident light is called fluorescence. The emission stops immediately on
removal of incident light. Teeth fluoresce with a stimulus in the range of
340nm to 410nm. This spectrum is in the blue range. Thus, according to the
principles of additive color, the emitted blue light acts with the yellowness of
the tooth to produce a whiter tooth. Fluorescing pigments incorporated in the
ceramic restorations by the ceramist and in the composite restorations by the
manufactures may thus be advantageously used in altering the perception of the
final result.
Gloss
Gloss is an optical property associated with a smooth surface that
produces lustrous surface appearance and thus reduces the effect of color
differences. Increase the brilliance (value0 of the final result.) In dentistry,
unlike spectral colors, the restorative materials have pigment colors
incorporated in them. Predictable restorative color outcome can only be

achieved by proper understanding of primary, secondary and complementary
factors.
Primary color
Are those colors that cannot be formed by mixing of multiple colors. They
occur naturally by themselves. For example, red, yellow, blue etc.
Complementary colors
According to the additive principle of colors, complementary colors can
be used to lower the value of the restoration and not to complementary color
may be added to the respective hue to decrease the value.
Perception of color.
The perception of color involves many physiological , physiological and
physiological aspects
The light source.
The light source has the color of the emitted light and is described in
color temperature (Kelvin.). The lighting environment makes a significant
differences in the perception of color. The teeth and the shade guide should be
sufficiently illuminated. The light reflected from a glossy surface obscures the
viewer‟s perception of light. Shadows should be eliminated as they reduce the
available light and hide details.
The dental operator maybe illuminated by combination of natural sunlight and
artificial light, The artificial light may be incandescent (predominantly) blue.
Also the ratio between the task light (which falls directly on the working area)
and the ambient light (derived from the surroundings), known as the contrast
ratio, should be higher than 3:1, but lower than 10:1. This can be attained by
regularly measuring the intensity of light, cleaning the diffusers and the light
sources any by replacing them when their effective life is over.
The observer
The stimulus of light travels through cornea, lens, aqueous and vitreous
humors and reaches the cones and rods of the eye. The cones function for day
light vision and color perception whereas rods are sensitive to the quantity of
light perceived. These stimuli are then sent to the brain, where they are
computed and interpreted as color. This complexity of color is further
modified by the embryonic development of the brain, aging process,
aberrations of color vision like color blindness, dichromatism, mental fatigue
and drug intake.
The object
The quality of the color of an object (the tooth) depends on its ability to
absorb, reflect, transmit or refract the light energy falling on it. The
surrounding environment greatly influences the color. The ceiling and the
walls reflect light and should not be pained in bright colors. Neutral colors like
grey or white should be selected.
Contrast effects
The background considerably affects the perception of color. Different
contrasts effects that alter the color vision, should be understood.
Simultaneous contrast

Is visualized when two objects are viewed at the same time. The light or
dark contrast can be correlated to the surrounding environment like skin tone,
hair color and brightness of adjacent soft tissues and teeth. Hence, brighter
shades should be chosen for light toned patients and darker shades for pigment
toned patients.
Actual contrast
Is influenced by the size and the chroma of the tooth. A brighter tooth
looks larger while a darker tooth of the same dimension look smaller.

Shade selection
Shade selection is a complex procedure due to the variations and
differences in the optical properties of the new generation of cosmetic
restoration materials. It can be well accomplished by understanding the
fundamentals of color and adopting a proper methodology of matching shades.
The effective communication with the laboratory and precise fabrication and
meticulous finishing of the restoration will affect the color of the final
restoration.
Shade selection sequence
Any color modification procedures like bleaching or microabrasion
should precede color selection after ensuring color stabilization.

Make the shade selection at the beginning of the procedure as well as
over different appointments (diagnosis, prophylaxis etc.)and cross check these
observations.

View the patients at eye-level. The operator should stand between the
light source and the patient.

In a contrasting environment, colors look more intense and brighter.
Hence it is wise to ask the patient‟s to remove artificial lip color.
Place the tabs as close as possible to the area that is being checked.

Moisten the tab and eliminate the worst match.

Evaluate the value (upper to lower). Value is the most important factor
in shade matching. If the value blends, small variation in hue and chroma will
not be noticeable. The value is to be matched with eyes half closed.

After value, mark the translucency

Match the chroma (more or less saturated) and finally, hue in that order.
To avoid hue sensitivity, rapid observation is made for 5 seconds (not more
than 20 seconds). Look away, ideally stare at a blue surface, which will
readapt the vision to the orange yellow portion of the spectrum.

Match prior to tooth preparation, since preparation dehydrates and
changes color due to the debris of preparation.

Match the tab with the opposing tooth also.
Metamerism complicates color matching, as the tabs look different under
different light sources. The best approach is to use three light sources; cool
white fluorescent light, incandescent operatory lamp and day light if possible.
When in doubt, always select higher value and lower chroma, since it is easy to
lower value and increase chroma


Shade tabs of different batches don‟t always match, hence it is wise to
sent the actual selected shade tab to the technician.
 Make a decision regarding relative translucency, area of hypo
calcification, increase saturation, crack lines surface texture and other
characterization. Make a drawing of the facial surface and record all patient
information graphically.
Dental Bleaching
Bleaching is one of the most commonly sought elective dental
procedures to brighten a smile. It is a simple, fast and effective treatment to
change darker tooth shades into lighter ones.
Chemistry of bleaching
Bleaching process is based on the oxidation of bleaching agent.
Oxidation is the chemical process by which organic materials are converted
into carbon dioxide and water. The oxidation reduction reaction that takes place
in the bleaching process is called the redox reaction.

Bleaching slowly transforms the organic substance in the stained tooth into
chemical intermediates that are lighter in color than the original tooth shade. In
a redox reaction the perioxide (oxidizing agent) has free radicals with unpaired
electrons, which it gives up, becoming reduced. The stained tooth structures
accepts these electrons and becomes and oxidized, thereby reducing the organic
colorants. The free radicals produced by the peroxides are perhydroxyl and
nascent oxygen. Of these, the perhydroxyl is a more potent free radical which
is responsible for a better bleaching action.
In order to promote the formation of perhydroxyl radicals, the peroxide is
buffered to a pH range of 9.5 to 10.8. The buffering provides a greater amount
of perhydroxl radicals, which results in a better bleaching effect.
The most common bleaching materials used are hydrogen and
carbamide peroxide. Carbamide peroxide first breaks down into hydrogen
peroxide which then further liberates the above mentioned free radicals. Unlike
the hydrogen peroxide, the carbamide peroxide bleaching agent must remain in
contact with the teeth for a longer period of time to obtain complete efficiency
of the reaction. Carbamide peroixde is less irritating to the gingival tissues thus
better tolerated by the patients when used as a home bleaching agent.
Mechanism of bleaching
In the presence of moisture as well as surface debris on the tooth, the
ionization by hydrogen peroxide occurs by decomposition into water and
nascent oxygen which is a weak radical making the peroxide which is a weak
radical making the peroxide inefficient as a bleaching agent. Hence, it is
important to have teeth dry and free of surface.
Increase in the temperature, higher peroxide concentration and the
duration of exposure of the tooth structure to the peroxide within limits, direct
affects the oxidation process leading to a greater degree of color change.
Saturation Point

Prolonged used of a bleaching agent causes the whitening action to
slowdown beyond a point during the treatment. This is the saturation point.
The bleaching if allowed to continue, begins to break the inorganic structure
from the enamel becomes rapid. Bleaching should thus be stopped at or before
the saturation point.
If bleaching is done beyond the saturation point, it clinically manifests
an increase in porosity on the tooth surface. A fluoride application is
recommended and no bleaching agents should be applied allowing the enamel
to remineralise.Procedure for bleaching
Use of concentrated heroine or carbamide peroxide solution available in
standard 35% concentrations. In a technique described as „assisted office
technique‟, 35% carbamide peroxide is tray loaded for 45 minutes, after
following required protocols. Some bleaching materials are available in a
combination of a hydrogen peroxide and carbamide peroxide in 20% and 16%
concentrations respectively. There are other “dual cure” systems, which
initiate the bleaching reaction on the tooth surface through a chemical reaction
which is catalyzed through light activation by a visible blue light spectrum.
Preparation of trays
The bleaching procedure is recommended for the number of teeth seen
in the patients active smile. 1 millimeter reservoir for the bleaching gel. On the
modified cast soft and clear vacuuform matrix of 0.035”thickness is made. The
matrix, carefully trimmed to cover only the clinical crowns. Contract the
bleaching gel with marginal gingiva may result in tissue irritation hence
vacuuform trays should have a marginal seal to eliminate contact of the caustic
bleaching gel with the gingiva.
Isolation of teeth
Proper isolation of area with cotton rolls or rubber dam is mandatory.
The gingival surface is wiped and dried sufficiently.
Etching of tooth surface
Each tooth is etched on labial surface for 10 to 20 seconds using 32% 37% orthophosphoric acid. This step removes any superficial surface stains and
enhances the penetration of the bleaching solution into the tooth surface
producing a greater stain reduction.
Excessive etching causes the
demineralization of the enamel matrix, leading to surface irregularities and
causing sensitivity. Application of bleaching material
The bleaching materials is slowly loaded in to the vacuufrom trays so
that it spreads all over the labial surface of the teeth to be bleached. The trays
are kept in place for an average duration of 30 minutes depending on the type
of material used and the manufactures recommendations.
Micro-finishing and polishing
Following bleaching, the teeth are micro-finished using fine abrasive
disks. Final polishing is done with aluminum oxide or fine grit diamond
polishing pastes.
Office bleaching of non vital teeth
The two most commonly used agents for bleaching of non-vital teeth are
hydrogen peroxide and sodium perborate.

Home bleaching
Bleaching may be carried out at home by the patient. The home bleach
technique involves the application of bleaching agent through the use of
vacuuform trays. The frequently used bleaching agent is 10% - 15% carbamide
peroxide.
Bleaching in relation to bonded restorations
It was determined in clinical studies that the bond strength of composite
to enamel is reduced when the tooth is bleached. The primary cause for the
reduced bond strength is the presence of the residual peroxide or oxygen,
which interferes with the polymerization of resin bonding systems and
restorative materials. Any bonded restorations in the bleached teeth need to be
done after a period of two weeks. If bonding cannot be delayed by two weeks
then the enamel should be roughened and acetone based adhesive system used.
Enamel microabrasion
Hydrochloric acid *18%) pumice abrasion can remove white enamel
opacifiers, multicolored defects and many brown, orange, yellow enamel spots
and streaks, regardless of etiology. These stains can be eliminated with
insignificant enamel loss if the stain is limited to a thin layer of tooth surface
(approx. 0.5mm). This procedure can be used independently or prior to
bleaching to give optimal results.
Management of Fluorosis stained teeth
A solution of anaesthetic either, hydrochloric acid and hydrogen
peroxide may also be used for bleaching teeth with fluorosis stains. The
anaesthetic either removes surfaces debris, the hydrochloric acid etches enamel
and hydrogen peroxide bleaches it.
Esthetics with composites
Considerations in preparation design for anterior teeth.
The preparation design for anterior composite restorations should
encompass elimination of decay, function and longevity, and esthetic
predictability.
Function and longevity
A pre-operative analysis of the occlusion is crucial to determine the
palatal extensions and the acceptable length in upper anterior restorations.
Checking the lateral and protrusive excursions will given an ideas as to how far
palatally the final restoration can be placed. Researchers have found that a
minimum of 1.5mm – 2mm of the composite thickness is essential to give
sufficient strength to the material. A conscious effort has to be made to leave
at least 2 mm of composite thickness at the margins for good marginal
adaptation and retention in larger restorations.
Esthetic predictability
After elimiantion of the decay and determining the extent of preparation
required for function and longevity , the preparations are evaluated and if
required redefined. The preparation design is extended to allow a smooth
transition of shade from the composite restoration to the rest of the tooth. This
enables the restorations to achieve esthetic excellence.

To create proper tooth from, shape, shade and texture, and to optimize
function, all cavity preparations designs should have extension for function and
esthetics (EFE).
The EFE ensures that the margin of the restoration overlays the defects. The
esthetic advantages are :

Successful masking of the defect

Better marginal adaptation

Natural transition of shade between composite and tooth

Ease of finishing and texturing
EFE and placement of composite for malaligned teeth
The preparation in malaligned teeth is a typical and depends upon the
degree of rotation and angulation exhibited by the teeth and hence a uniform
layer of composite cannot be placed to treat such teeth. The effective use of
opaque composites in areas having no tooth or thin palatal structure, improves
the blending of the restoration. Creating surface characteristics and effectively
placing the transitional angles on the facial surface can help to over come
deficiency in tooth reduction.
EFE and placement of composite for closing spaces
Diastemata may be manifested to due to microdontia, discrepancy
between tooth size and the available ridge and also due to variation in the tooth
morphology.
Although some natural spaces may be esthetically and
phonetically acceptable, others are not and need corrective restorative
procedures. However, in cases where the size of the teeth is normal and a
diastema still exists, restorative creations using principles of illusion is
recommended.
When a diastema is small up to 2mm, no tooth preparations is required. The
minimal thickness of composite can be adequately shaped especially at the
cervical region to allow good maintenance. However, in cases of a moderate
diastema between 2-4mm the EFE should be given on the proximal curvature
of the labial surface of the tooth. The extension preparation is close to the
gingival margin and follows the contour of the inter dental papilla to end on the
palato-proximal line angle. The preparation is in the form of a depression,
which provides a definite stop and is done with a chamfer bur.
The preparation design ensures adaptation of sufficient bulk of the
composite at the gingival margin creating contours favorable for gingival
health. The labial extension allows smooth blending at the composite tooth
interface while the palatal extension provides stability and retention. In cases
with diastemata larger than 4mm a similar preparation coupled with
recontouring of the other proximal surface of the tooth to maintain tooth
proportions and form may be required. Diastemata are filed in one tooth at a
time. A celluloid matrix is effectively used to get the desired contour
EFE and placement of composites in cervical defects
Cervical defects are caused due to caries, abrasion, erosion or abfraction
and a combination thereof. Although management of these defects involves
similar procedures, their proximity to the gingiva makes it difficult to restore.
Before any preparation, a gingival cord is placed in the sulcus to allow a proper

access to the defect and to keep away sulcular fluid or blood from the cavity
margins. Since bond strengths with the cementum are weak, no additional
bevel is recommended at the cervical region in cases where the base is in the
cementum.
round bur is used to roughen the surface of the cavity and a long bevel is placed
on the occlusal edge of the cavity. After etching, the cord ischanged and
bonding adhesive is applied followed by flowable composite which is used as
an intermediate layer. The gingival cord is removed after completion of the
filling to facilitate finishing and polishing. The occlusion is adjusted,
especially eccentric contracts, to take care of primary or secondary abfractions.
Fine diamonds or carbides are used to finish the margins.
Tissue management
Success of composite restorations depends not only on preparation
design, bonding procedures, quality of restorative material and skill of the
dentist but it also largely dependent on the thoroughness of the isolation. The
greatest challenge involved in creating predictable composite restorations near
the gingival margins is to achieve hemostasis and control of sulcular fluid.
Therefore, tissue management becomes an integral element of these
procedures.
case of contamination of composite by blood, blood pigments containing iron
or ferric sulphate migrate between the composite and tooth surface or between
different layers of composite. These pigments turn dark and are visible as a
black-brown discoloration in the restorations. Salivary contamination as well as
crevicular fluid ingress in the preparation can cause bonding failures at these
areas leading to the failure of the restoration.
Retraction cords displace the gingiva and keep blood and suclurlar fluid away
allowing proper access with contamination during placement and finishing of
composites. In cases where the cavity design is close to the gingival margin,
double retraction technique can be effectively used. Astringent impregnated
cords should be used with caution as nay residual astringent can potentially
contaminate the tooth surface to be bonded causing a bonding failure.
Shade matching
Shade selection is done following standard protocol with references to
the incisal third, middle third and the cervical third of the tooth. The
uniqueness of composites permits pilot shade test to reconfirm shade attributes
before final restorations. The pilot shade test is carried out using a selected
shade in a bulk of 1.5mm- 2mmon the involved tooth and a contra lateral or
guide tooth. The composite is then cured and finished and the accuracy of the
shade match is confirmed. Any changes in the value, transluency and chroma
is recorded and the shade is changed if required.
Three procedural steps for finishing and polishing

Gross reduction, contouring , defining the margins. Fine grit diamond
abrasive or tungsten carbide finishing bur can be used for the these purposes
(100µm size abrasives)


Intermediate finishing is used to reduce scratches left by gross
reduction and to blend all surfaces with each another keeping the orientation of
various facial planes intact (less than 100µm but morethan 15-20 µm particle
size).

Final abrasive polishing imparts enamel like effect on the restorations.
Loose abrasive devices, disks, pastes with particle size less than 20µm is used.
Esthetics with Ceramics
Ceramics laminate veneers
In 1930 Charles Pincus used a unique procedure to improve the smiles
of certain Holly wood actors. This technique was non-invasive and gave good
esthetic results with resin and air fired ceramics. But the veneer coping made
then lacked permanent retention and later this technique was discontinued.
Considerations in tooth preparations for ceramic laminates
Tooth preparation design will depend upon the existing color of the
teeth, whether change in alignment or an increase in height of the final
restoration is sought.
When a mild to moderate discoloration has to be
masked the preparation can be minimal from 0.3mm cervicaly to 0.5mm at the
incisal edge. Whenever a severe discoloration has to be masked the
preparation has to be deeper to allow more die spacer to be applied on the
model. His excessive space allows use of resin curing cement to mask the
severe discoloration. Adding more opaque ceramic in the veneer will mask
undesirable tooth color but will limit the display of vitality.
more translucent ceramic will allow more light transmission and reflection
internally making the restoration more vital. If change in alignment is indicated
then more preparation will be required in certain areas. When length of the
veneer has to be increased a palatal extension is recommended.
Preparation of maxillary teeth for ceramic laminates

Mock preparation on the pre-operative casts and diagnostic wax up
gives valuable information about he amount of tooth preparation and helps to
visualize the end result.

Local anesthesia may be required when the preparations reaches the
dentin and to facilitate easy gingival retraction procedures.
Self-limiting three-tiered depth cutting burs of known dimensions (0.3mm and
0.5mm) facilitate repaid, adequate and conservative tooth reduction. The depth
roves are made by moving them on the facial surface from the mesial to the
distal and by changing the angle of the bur to facilitate their orientation in two
planes (Fig. 8-1a). Then the facial reduction is achieved following the labial
contour of the tooth till the depth grooves. Besides, the contra-lateral tooth can
be used as a reference to check adequate tooth preparation. Selective labial
tooth preparation is required to create a favorable arch form.
A modified chamfer margin is preferred to allow distinguishable finish line in
the impression, definite seat and adequate bulk for laminates. The margin is
usually supra-gingival or equip-gingival. The margin is taken intra-crevicularly
in certain cases to mask the underlying discolored tooth and cover cervical
lesions.


The proximal finish line is placed into the embrasure area to ensure that
the margin between the laminate and the unprepared tooth structure is well
hidden. Deficient preparation reveals unaesthetic margins proximally.
Incisal preparation depends on whether an increase in tooth height is required
or not. In case where the increase in not sought, the incisal preparation ends
midway between the labio-lingual width of the incisal edge. A facio-incisal
angle of 30o with a definite stop (window preparation)is given. Butt joints are
rarely recommended .
In case when the length of incisor is to be increased, the incisal table is
flattened with a bevel of 45o palatally. The palatal preparation is a wraparound design with the margin placed inferior or superior but never at the
contact of the mandibular incisor in centric occlusion
Similarly, window preparations are advocated for canines and premolars when
increase in height in not required.

When the length has to be increased, the anterior and lateral guidance
has to be considered and appropriate tooth preparations has to be carried out to
allow for adequate thickness of the laminate at the incisal or occlusal area.
Provisionalization of laminates
Good provisional help in visualizing the final outcome and can give adequate
information of the shade and shape of the laminate to the patient and dentist.
Making and placing provisionals for laminate preparations is made tedious than
provisionals for crowns. Due to the poor strength of the thin provisionals, there
is a possibility of breakages during removal and inadequate luting strength.
There are various methods of making provisionals for laminate
preparations. Composite resin is directly sculpted on the prepared tooth after
spot etching and bonding at the center of the tooth and cured to get esthetically
acceptable provisionals. This technique is simple, comparatively less time
consuming and cost effective than others.
Another technique involves making a vocuum formed shell of clear
plastic sheet on a preoperative cast. The shell with light cured resin is then
placed against the prepared teeth. After the composite is cured, the shell is
separated and finished provisionals are luted to the preparations.
Try in
Chair side try-in is done to check individuals veneer fit, collective fit of
veneers and the shade of the composite luting cement that should be used to get
the desired final result.
Individual veneer is tried for marginal fit, adaptation and retention. Any
premature contacts are relieved at this stage. The veneers should fit in
passively with good contacts and not actively as it may lead to displacement of
some veneers .
Cementation
The patient is viewed periodically for the gingival response and
maintenance regimen. Usually a 3month check up followed by a 6 monthly
check up is recommended.

Metal ceramic and all-ceramic restorations
Metal ceramic and all ceramic restorations have excellent esthetic
potential. The metal ceramic restorations owe their popularity to the simplicity
of bridge construction, durability, strength, marginal adaptation and versatility
of use.
Can be used successfully for various complex clinical situations like long span
bridges, full mouth rehabilitation as also a number of semi-fixed type of
appliances.
All ceramic restorations are characterized with a dentin like core which
makes it possible to mimic the translucency of natural teeth. They are biocompatible with the gingival tissues and exhibit excellent marginal fit due to
newer thermoplastic processing while some exhibit wear resistance similar to
that of enamel. All ceramic restorations are indicated for crowns, veneers,
inlays, onlays and three unit bridges with the premolar as the distal most
abutment.
Although all anterior teeth were esthetics is a prime concern can be indicated
for all ceramic restorations, caution has to be taken when a para-function,
exists, when tooth structure is insufficient to support the ceramic, in short
clinical crowns and when the lingual preparations is thinner than 0.8mm. In
such cases a metal ceramic restorations is functionally stable and indicated.
Imperatives of tooth preparations

Length and taper of the preparation for retention and resistance.

Enough reduction to allow thickness of the ceramic for excellent
esthetics.
Occlusal clearance for occlusal function and anterior guidance.
Tooth preparations for metal ceramic crowns.
The incisal edge reduction of 1.5mm – 1.8mm and the occlusal
reduction of 1.5mm – 1.7mm with functional bevel is recommended .
Reduction is achieved by using a wheel diamond on the incisal edge or a round
diamond of known diameter in the occlusal grooves. The incisal edge
reduction is followed by the labial reduction. When reducing the labial surface
of the tooth, the exact contour must be emulated. This helps to prevent excess
removal of tooth structure which may lead to deficient lingual wall preparation
especially at the incisal aspect. The labial reduction is achieved in two planes
with a round-ended tapered bur, the first orientation involves the incisal two
thirds of the tooth. The palatal reduction is carried out allowing sufficient space
for the crown and to re-establish normal occlusal and protrusive relationships.
A pear shaped or rugby diamond is used to reduce the lingual concavity while
the rest of the cingulum surface is reduced with a round ended tapered
diamond bur.
The proximal reduction involves smooth movements from the labial
surface to the palatal allowing is finished margin on the proximal surface.
Long tapered fissures can be initially used followed by round ended fissure
burs to achieve desired reduction. Preparations must include 1mmm peripheral
shoulder or chamfer with bevel for ceramometal crowns. The objectives is to

achieve a convergence angle of the axial walls in the range of 6o to 100.A
shoulder with a 90o cavo-surface angle or a stopping shoulder of 120o is
recommended for a adequate support of porcelain. When the metal margin is
shortened for esthetic reasons, shoulder porcelain requires 1.2mm of tooth
reduction at the margin. The shoulder with a long bevel is advocated for
improved marginal fit but it cannot be accommodated in shallow gingival
sulcus. Hence short bevel of 0.5mm with a cavo-surface angle of 135o is
preferred. Chamfer (0.5mm)is the finish line of choice for metal backing. For
porcelain fused to metal backing, a metal collar on a modified chamfer is
preferred. The palatal chamfer is blended smoothly with the labial shoulder
lingual to the contact area for good esthetic results. All sharp line angles
within the preparation should be rounded to reduced stress concentration.
Tooth Preparation for all ceramic crowns.
Although the preparation sequence for all ceramic restorations is similar
to the metal ceramic one, the main concern for the dentist in the preparation
for the all ceramic crowns should be to minimize the stresses that could be
incorporated on the ceramic in function.
The length of the preparations is important as load applied from a
lingual direction on a short preparations can lead to severe compression of the
labial shoulder leading to a fracture. The incisal edge is reduced to get flat area
however a reduction in excess of 3mm is avoided. In some cases a reduction of
up to one third of the crown height may be required to get rid of the thin
incisal edge. The facial reduction is achieved in two planes at a depth of 1mm
to 1.5mm.The lingual aspect should be shaped to remove any uneven surface or
sharp line angles and should incorporeated or sharp line angles and should
incorporate a definite lingual concavity with a high lingual axial wall
whenever the cingulum prominence and occlusion is favorable. Lingual depth
should be 1mm – 1.5mm and should not be less than 0.8 mm. The proximal
preparation is completed with a taper of 6o-8o and will help in one path
insertion. Excessive taper will cause inadvertent forces on the ceramic and
leads to reduction in flexural strength.
The facial reduction, lingual reduction and the proximal reduction should end
into a well defined shoulder. The shoulder should not create any undercuts for
the restorations and hence any angle in excess of 90o should be avoided. The
shoulder should not necessarily be uniform labially, proximally and lingually,
as excessive reduction may be required to do so, compromising on the
resistance and retention form of the preparation. The shoulder is usually
0.8mm – 1.0mm wide in the labial and lingual and 0.5mm – 0.6mm in the
proximal aspect where the ceramic flares to give sufficient strength. The
smooth finish line should not be steep inter proximally but have a smother
gradient to avoid potential stress area during function.
As a compared to the preparation for metal ceramic restorations, the finish line
for all ceramic restorations should be a shoulder which is at right angles to the
direction of stress thus increasing the fracture resistance. In the final
preparation all sharp line angles and undercuts are avoided providing maximum
strength and resistance. Adequate length of the preparation is required in order

to counter the tipping forces and increase the surface area for additional
retention.
The depth of the facial and lingual shoulder should be 1.0mm (with a
minimum of 0.8 mm) and interproximally the shoulder can be 0.5mm as the
restoration flares interproximally. A taper of 5o - 10o is advisable for
conservity and increased support to the restoration. Increased taper leads to
stress concentration in areas where the support is lacking.
Try-in
All metal castings are evaluated for margin integrity, internal fit,
stability and adequate space for ceramic material. Intra occlusal relationship
record is needed in extensive rehabilitation cases. Bisque trial for ceramic
restorations are assessed for location, site and tightness of proximal contacts,
marginal adaptation and favorable centric and eccentric occlusal contact
without interferences. Besides the shape, contours and color; adequate surface
characterization is checked and incorporated.
The trial for all ceramic restorations are assessed for a passive fit,
margins, proximal contacts, stability, shade, form, characterization and
occlusion. -implant esthetic consideration
In cases of anterior implants in the esthetic zone, certain specific
esthetics criteria have to be considered. When esthetics is the prime reason for
seeking implant prosthetic treatment, the patient‟s upper lip line will be of
extreme importance for the planning of the definitive superstructure. In
patients with a high lip line or requiring upper lip support from the prosthesis a
removable over denture will more likely fulfill the demands of function and
esthetics than an implant borne bridge construction.
The single tooth anterior implant situations is of great concern as the esthetic
requirements and expectations have to be properly balanced keeping in mind
anticipated post-surgical results. The dentist should analyze anterior single
tooth implant situations considering the adjacent teeth, contra-lateral tooth,
probable emergence profile and presence or absence of inter dental papilla
when ever the active smile exposes enough of gingival tissues.
There are many limitations and contra indications specific to the maxillary
single tooth implant apart from the routine contra indications associated with
implant therapy. The common causes of a missing maxillary tooth is traumatic
loss, root fracture, agenesis and periodontal disease. All these leave some
deficiency in the facial bone over the root of the missing tooth. Majority of
the cases of maxillary single tooth implant in patients with high upper lip line
require bone grafting for ideal esthetics while in some cases bone grafting
would be necessary to provide adequate healthy peri-implant soft tissue to
maintain optimal hygiene in the cervical region.
There are many limitations and contra indications specific to the maxillary
single tooth implant apart from the routine contra indications associated with
implant therapy. The common causes of a missing maxillary tooth is traumatic
loss, root fracture, agenesis and periodontal disease. All these leave some
deficiency in the facial bone over the root of the missing tooth. Majority of
the cases of maxillary single tooth implant in patients with high upper lip line

require bone grafting for ideal esthetics while in some cases bone grafting
would be necessary to provide adequate healthy peri-implant soft tissue to
maintain optimal hygiene in the cervical region.
Apart from the inadvertent deficiencies in the facial bone associated
with various clinical situations, the soft tissue form also plays a major role in
the esthetic outcome of single tooth implants.
In 1989, Misch reported 5 prosthetic options available in implant
dentistry. The first three options are fixed prosthesis (FP). The next two
options are removable prostheses (RP).Prosthodontic classificationType
Dentition FP – 1Fixed Prostheses, replaces only the crown, looks like a
natural tooth.FP – 2Fixed Prostheses, replaces the crown and a portions of the
root; crown contour appears normal in the occlusal half but is elongated or
hyper contoured in the gingival half. FP – 3Fixed Prostheses ; replaces missing
crowns and gingival color and portion of the edentulous site; prostheses. Most
often uses denture teeth and acrylic gingiva, but may be porcelain to metal. RP
– 4 Removable prostheses ; over denture supported completely by implant. RP
– 5 Removable Prostheses ; over denture supported by both soft tissue and
implant.
Fixed Prostheses FP-1 –
FP-1 is a fixed restorations and appears to the
patient to replace only the anatomic crowns of the missing natural teeth. There
usually has been minimal loss of hard and soft tissues. The final restorations
appears very similar in size and contour to most traditional fixed prostheses
used to restore or replace natural crowns of teeth. FP –1 prostheses is most
often desired in the maxillary anterior region. However the width and / or the
height of the crestal bone is frequently lacking, augmentation is often required
before implant placement to achieve a natural looking crown in the cervical
region because there are no inter dental papillae in edentulous ridges,
gingivoplasty is required after the abutment is positioned to improve the
interproximal gingival contours. Ignoring this step causes open “back”
triangular spaces (where papillae should usually be present) when the patient
smiles. The bone loss and lack of inter dental soft tissue complicates the final
esthetic results, especially in the cervical regions of the crowns.FP-2 fixed
prosthesis restores the anatomic crown and a portion of the root of the natural
tooth. The volume and topography of the available bone dictate a deficient
vertical implant placement compared with the FP-1 prosthesis, which is more
apical compared with the cemento-enamel function of a natural root. As a
result the incisal edge is in the correct position, but the gingival third of the
crown is over extended, usually apical and lingual to the position of the
original tooth. If the high lip line during smiling or low lip line during speech
are favorable and do not display the cervical regions, the longer teeth are
usually of no consequence. FP-2 prosthesis that are not hidden by lip position
during smiling or speech can be solved by using a removable soft tissue
replacement device. The FP-3 is a fixed restorations that appears to replace the
natural teeth crowns and a portion of the soft tissue. As with the FP-2
prosthesis, the original available bone height loss decreased by natural
resorption or osteoplasty at the time of implant placement. To place the incisal

edge of the teeth in proper position for esthetics, function, lip support and
speech, the excessive vertical dimension to be restored required teeth that are
unnatural in length. The patient having high maxillary lip line during smiling
and low mandibular lip during speech, will display the longer teeth which look
unnatural. In the AP 3 the restored gingival colour and contour give the teeth a
more natural appearance in size and shape and mimic the inter dental papilla
region. The addition of gingival tone acrylic or porcelain for a more natural
appearance is often indicated.
RP-4 It is a removable prosthesis completely supported by implants and or
teeth.
It may draw the same appearance as an FP-1, FP-2, FP-3
restorations. RP – 5It is a removable prosthesis combining implant and soft
tissue support. The prosthesis is very similar to traditional over denture Factors
for favorable implant placement
The physiologic limits with in which the implant can be placed are
governed by the following

The space between implant and periodontal ligament of the adjacent
tooth should be 1mm.

The average width of periodontal ligament is 0.25mm.
These natural periodontal components will require a space of 1.25mm on either
side of the implant. Thus, mesio-distally the implant diameter is added to this
minimum space required. The facio-lingual requirement. For a 3.5mm implant
placed in the anterior region a minimum of 6mm of space mesio-distally has to
exits to accommodate all related components. Ideally, the ridge should be 56mm wide labio lingually, to allow at least 1 mm of the cortical bone labially
and lingually. However, to impart esthetics in the inter dental papilla region,
the distance between an implant and natural teeth is kept 2mm.
The implant should be 3mm apical to the gingival margins of the
adjacent teeth.
Labio-lingual orientation of the implants helps to achieve desired
emergences profile. Placing the implant slightly palatally helps the dentist to
build up a proper emergence profile to the crown.
To obtain satisfactory peri-implant gingival morphology, tissue volume
should be 20-25% more than the estimated need to allow adaptation of gingiva
to the prosthetic reconstruction.
Wider diameter implant will ease the transition of the implant head to
the artificial crown as it emerges from its soft tissue housing. The wider
diameter implants will not be required to be placed far apical to the cementoenamel junction of the adjacent tooth. Immediate implants help to preserve the
hard and soft tissues, and maintain the emergence profile as in natural teeth.
Shape and positioin of the gingival:
In an ideal esthetic relationship, the position of the gingival margin is
dictated by the vertical limits of the active smile, the gingival margins of the
maxillary central incisors and canines positioned at the vermilion border of the
upper lip. The gingival margin of the lateral incisors is usually located 1 to 2
mm more incisally or at the same height of the central incisors and canines.

The gingival zenith is distal to the long axis of the tooth for both the
maxillary central incisor and canine while it is situated on the long axis of the
tooth for the maxillary lateral incisors.
The degree of scallop of the gingival margin depends on the periodontal
morphotype. Thick morphotypes have flatter gingival contours and thin
morphotypes have more scalloped gingival contours. The gingival height of
contour of the premolars and molars lies in a more occlusal position as it moves
posteriorly.
The horizontal limits as well as the vertical limits of the smile should be
evaluated. Most patients show the maxillary teeth with or without the gingiva
upto the first molar in an active smile. To provide for proper depth and
harmony of the smile, the gingival display should be consistent and
proportional from tooth to tooth, from the left first molar to the right first
molar.
Embrassures
In healthy periodontium the inter dental papilla blends into embrasure
spaces completely from buccal to lingual which is an important esthetic factor
assuring harmony in the dental composition. However, in cases of recession or
post-periodontal therapy the embrasures may open up revealing a black
triangle.
Biologic width
It has been demonstrated fro autopsy recordings that the mean sulcus
depth is 0.69mm, mean length of the junctional epithelium is 0.97mm and
connective attachment is 1.07mm; the combined width of the latter two is 2.04
mm and is called the „biologic width‟. This biologic width is always present,
therefore restorative margins must maintain a distance from the alveolar crest
that respects the biologic width, otherwise gingival recession or pocket
formation ensues.
Esthetic periodontal defects and its correction
Periodontal defects posing an esthetic problem.
May include :

Violations of biologic width

Gingival asymmetries

Excessively gingival display

Localized gingival recessions

Deficient pontic areas

Abnormal frena.

Excessive gingival pigmentation

Inadequate interproximal papilla Biologic width” considerations during
restorative procedure
The dentist should consider the following aspects to esthetically plan
procedures involving re-establishment of the biologic width

Location of the restorative margins

Location of the gingival margins

Location of the crestal bone

Restorations which are over extended in the cervical region should be carefully
removed and proper cleaning of the teeth is recommended with excavation of
deep carious lesions in the cervical region. Provisional restorations should then
be fabricated with proper contouring in the cervical region. The pockets should
be probed and isolated areas of excessive bone loss should be marked and
regenerative procedures instiuted.
Surgical technique for establishing proper biologic width involves
recontouring the osseous crest so that a minimum of 3 mm of the flap can be
placed coronal to the position of the recontoured osseous crest. This will take
into consideration the average biologic width of 2mm.
accidental tooth fractures or any other clinical situations where the restorative
margins may violate the biologic width, bone removal in the adjacent teeth
might be necessary to get desired esthetic result.
Gingival asymmetries
Whenever the facial gingiva of the anterior teeth does not follow a
symmetrical pattern, crown length discrepancies are perceived; some teeth
appear longer while others appear shorter. Correcting these discrepancies to an
esthetic gingival pattern becomes the main goal of the esthetic or restorative
dentist.
The possible causes of gingival asymmetries are :

Gingival hyperplasia

Altered passive eruption

Tooth or teeth malpositioning

Over zealous tooth brushing

Periodontal disease
Esthetic crown lengthening
When a disparity in the clinical crown length exits between contra
lateral teeth resulting in a left/right side height discrepancy, esthetic surgical
correction can be provided to enhance the cosmetic result before restorative
measures.
In such cases „esthetic crown lengthening‟ may be carried out by
performing gingivectomy and or osseous resection only on the facial aspect, for
better esthetics. Root exposure is often a common complications and
intentional root canal or post surgical treatment with veneers or crowns may be
required.
Excessive gingival display (gummy smile)
A gingival display of more than 3mm in active or moderate smile may
be termed “gummy”. Excessive gingival display or gummy smile can be
caused by any of three factors.
The causes include :

Maxillary over growth

Tooth malposition

Delayed apical migration of the gingival margin or altered passive
eruption.
Crown lengthening procedures can correct the latter two defects. However, in
cases of excessive gingival display of more than 5mm a cephalometric analysis
is recommended.

Usually a surgical and orthodontic correction may be needed in these
cases.Deficiencies in edentulous ridges
Deficiencies in edentulous ridges could be bucco-lingual, apico-coronal
or a combination of tooth. These deficiencies can lead to functional as well as
esthetic compromises for prosthodontic and implant related treatments.
Several surgical technique have been devised to restore the contour of
edentulous ridges that have been altered by disease or trauma before adaptation
of pontics. The most commonly used classification is as follows :
Class I :
Bucco-lingual loss of tissue with normal ridge height in an
apicocoronal direction.
Class II :
Apico-coronal loss of tissue with normal ridge width in a buccolingual direction.
Class III : Combination of bucco-lingual and apico-coronal loss of tissue
resulting in a loss of normal ridge height and width.
Correction of class I type of defects
Bucco-lingually edentulous ridge defects are the most commonly
encountered and most predictably treated of all alveolar ridge defects. Surgical
procedures such as inter positional grafts of hydroxyapatite or connective tissue
are ideal for augmentation for such type of defects.
For connective tissue grafting, the donor site selected is usually the one
with the thickest available connective tissue, such as maxillary tuberosity.
Augmenting the edentulous ridge at the time of surgery slightlyl more than
necessary will compensate for the shrinkage that occurs during surgical
healing.
Correction of class II defects
These are more difficult to treat predictably and are usually corrected
with onlay grafts. Slight defects in any plane of space can be treated. Usually
in one stage while moderate to severe type of defects often require multiple
procedures with an interval of 6 to 8 weeks post operatively.
Correction of class III defects
This is the most difficult type of defect to manage and generally requires
multiple surgical procedures. Palatal donor sites fill in totally within 4-8 weeks
and can again serve as donor sites, if necessary. When multiple procedures are
anticipated the bucco-lingual dimension is generally recaptured first, this
sequence provides a broader base (more vasularity) for the on lay graft.
The provisional restoration design is of crucial importance to maneuver
the soft tissues covering the ridge. For esthetically pleasing restorations
various pontic design are used; however much has been spoken about the ovate
pontic. The ovate pontic is highly convex and sits well within the confines of
the alveolar ridge. The ovate pontic contacts the alveolar ridge in a depressed
area, which helps to create good emergence profile for the pontic. However,
this pontic is very difficult for the patient to maintain. Abnormal
frenal
treatment
For diastema closure. A resection (frenectomy) or a repositioning
(frenotomy) may be necessary. Whenever there is excessive pressure caused
by the frenum then a frenectomy may be the best procedure, however when

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