Congenitally Missing Maxillary Lateral Incisor

Mansoura University
Faculty of Dentistry
Department of Orthodontics

Congenitally Missing Teeth
• Congenital absence of teeth results from disturbances
during the initial stages of formation of a tooth—
initiation and proliferation.
Contemporary Orthodontics , William R. Proffit ,5th edition

Terms :
Anodontia
The total absence of teeth ( the extreme
form).
Oligodontia
Congenital absence of many but not all teeth
Hypodontia
The absence of only a few teeth.

• Since the primary tooth buds give rise to the permanent tooth
buds, there will be no permanent tooth if its primary predecessor
was missing.
• It is possible, however, for the primary teeth to be present and for
some or all the permanent teeth to be absent.
Radiographs of two patients showing lower right second primary molar without successor

Panoramic radiograph showing upper right primary lateral incisor without permanent successor

Tooth Agensis (Hypodontia)
• Agenesis of one or more teeth constitutes one of the
most common developmental anomalies in man.
Transmission :
• an autosomal dominant, recessive or X-linked
condition.
• Tooth agenesis is more frequent in the parents and
siblings of individuals with missing teeth than in the
population as a whole, a finding that supports the
hypothesis that this condition is genetically
determined
Gender : Females > Males
Location : maxilla  mandible.
Treatment Planning Considerations in Congenitally Missing Maxillary
Lateral Incisor: The Role of Orthodontics (In Orthodontic Aspect)

Incidence :
• permanent tooth agenesis varies from 1.6 to 9.6%,
excluding third molars, which occurs in 20% of the
population.
• Some studies have shown that it is the maxillary lateral
incisor, whereas others believe that mandibular second
premolar agenesis has a higher incidence.
• Muller et al found an interesting correlation that
maxillary lateral incisors are the most frequently missing
teeth when only 1 or 2 teeth are absent, whereas second
premolars are the most frequently missing teeth when
more than 2 teeth are absent.

CONGENITALLY MISSING
MAXILLARY LATERAL
INCISOR

Tooth agensis of maxillary lateral
incisor
• The maxillary lateral incisors are frequently missing or
malformed.
• The percentage varies depending on the study consulted but in
most practices is about 5% of the patients treated.
Orthodontics Current principles and techniques , (Graber Vanarsdall Vig , 5th edition )

• A maxillary lateral incisor may
be missing unilaterally or bilaterally.
• A unilateral absence of maxillary
lateral is associated with small or
microdontic contralateral lateral incisor.
• Bilateral microdontic lateral incisors are often encountered in
clinical practice.
Unilateral absence with
microdontic contralateral
tooth
Bilateral absence Bilateral absence
Orthodontics Diagnosis and Management of Malocclusion and Dentofacial Deformities

Sequelae of congenitally missing
lateral incisor
• When the lateral incisors are missing, one of two sequelae
usually is observed :
• In some patients, the erupting permanent canine resorbs the
primary lateral incisor and spontaneously substitutes for the
missing lateral incisor, which means that the primary canine has
no successor and is sometimes retained .
• Some of these patients are seen as adults with primary canines
in place, but most primary canines are lost by the end of
adolescence even if their successors have erupted mesially.
Contemporary Orthodontics ,
William R. Proffit ,5th edition
Patient with permanent and deciduous canine

• Less often, the primary lateral is retained when the permanent
canine erupts in its normal position.
• This usually means that the lateral incisor space is reduced to
the size of the primary lateral incisor and the remaining primary
incisor is unaesthetic.
Retained deciduous lateral
incisor and deciduous canine
Retained deciduous lateral incisor with
permanent canine

Diagnosis
• The patients who have a congenitally missing lateral incisor seek
treatment in the dental office at a relatively young age.
• This is because the spacing is associated with the maxillary
anterior aesthetic zone.

• When permanent teeth are congenitally missing, the patient must
have a thorough evaluation to determine the correct treatment.
• Because any of the diagnostic variables of profile, incisor position,
tooth color and shape, skeletal and dental development or position,
and space availability or deficiency can be crucial in treatment
planning.

Clinical Features
• Midline diastema because the permanent central incisors
frequently move distally into the available space.
• Retained deciduous canine so ectopic eruption of the permanent
canine.
• Occasionally, canine impactions may also occur.

Radiographic examination
• Panoramic imaging is an excellent technique for screening for
missing teeth for diagnostic purposes.
• An OPG taken at the age of 7 years in a normally growing child
should show all the teeth except 3rd molar buds, which are seen
around 9 years of age.
Radiograph showing bilateral absent permanent tooth bud of maxillary lateral incisor

Photographs and radiograph of a patient showing clinical features of
bilateral congenital missing of maxillary lateral incisor including
midline diastema , retained deciduous canines and impacted canines

Photographs and radiograph of a patient showing clinical features of bilateral
congenital missing of maxillary lateral incisor including
midline diastema and retained deciduous lateral incisor

Photographs and radiograph of a patient showing clinical features of bilateral
congenital missing of maxillary lateral incisor including
midline diastema , retained deciduous canines and impacted canines
Case from Orthodontic Department ,Faculty of Dentistry Mansoura University

Relation between missing lateral
incisor and Canine impaction
• The role of the lateral incisor root is considered critical for the
normal eruption of the maxillary canine.
• Absent or microdontic maxillary laterals have been associated with
increased incidence of maxillary canine impaction.
• It seems that a missing or hypodontic
lateral incisor fails to guide the canine,
which dives into the palate causing
impaction or ectopic eruption .
Unilateral ectopic eruption of
permanent canine in the palate
with absent maxillary lateral incisor
and retained deciduous canine

• The ‘Guidance Theory’ proposes that palatal canine displacement is a
result of local predisposing causes including congenitally missing
lateral incisors, supernumerary teeth, odontomes, transposition of
teeth and other mechanical determinants that interfere with the path
of eruption of the canine.

• Up to 33% of patients with palatally impacted cuspids also have
congenitally missing teeth, 4-9 times more frequent than that of
the general population.
• Studies also show that up to 47.7% of patients with palatally
impacted cuspids have small, peg-shaped or missing lateral
incisors.
Patient with bilateral congenitally missing laterals and bilateral canines impaction

• In patients with congenitally absent maxillary lateral incisors,
the co-occurrence of palatally impacted canines is 2.4 times that
of the general population.
• However, it remains uncertain whether the anomalous lateral
incisor is a local causal factor for palatally displaced canines or
an associated genetic developmental influence.
Closed exposure of an impacted canine accompanying congenitally missing
lateral incisors

SPACE CLOSURE OF SPACES OF
CONGENITAL MISSING LATERALS

ACID ETCH RETAINER BRIDGE FOR RIGHT
LATERAL AND VENEER FOR LEFT LATERAL

CASE REPORT
Palatally impacted maxillary canine with
congenitally missing lateral incisors and midline
diastema
Sumit Yadav, Madhur Upadhyay, Flavio Uribe, and
Ravindra Nanda

Diagnosis
• A 13-year-old post-pubertal girl with the chief complaint of
spacing between her maxillary central incisors
• She had a Class II (end on) molar relationship bilaterally.
• The maxillary labial frenum was attached to the incisive papilla.
• The patient had retained deciduous canines and congenitally
missing lateral permanent incisors in the maxillary arch.
Palatally impacted maxillary canine with congenitally missing lateral incisors and midline diastema

• The orthopantomogram showed that both maxillary canines were
bilaterally impacted, and the occlusal and periapical radiographs
confirmed that the impactions were palatal.
Tomograms showing the
positions of the impacted
canines: A, right side; B, left side.
Pretreatment
radiograph

Treatment Plan
• The impacted canines would be surgically exposed and brought
into the arch using cantilever mechanics; the retained deciduous
canines would be extracted.
• The congenitally missing lateral incisors and impacted canines
would be replaced with the canines and the premolars,
respectively.
• The midline diastema would be closed; to prevent the relapse, the
labial frenum would be surgically resected.
• The deepbite would be corrected and an ideal occlusal
relationship established.

Treatment alternatives
• The second option was to distalize the molars bilaterally to
achieve an Angle Class I molar relationship and to restore the
space for prosthetic implants in place of the congenitally missing
lateral incisors, but this option was rejected because the patient
was only 13 years old, and we must wait at least 5 years before
placing implants and for economic causes
• The other option was to convert the deciduous canines into
lateral incisors, but this option was also rejected because more
than half of the roots of the canines were resorbed, and we were
not sure about the longevity of the deciduous canines.

Treatment Progress
Phase 1 The maxillary right and left canines were surgically exposed, and gold
chains were connected to the attaching device (button) on the impacted
canines and initial orthodontic traction was applied.
Phase 2 Fixed appliance therapy aimed at creating space in the maxillary arch
to accommodate the maxillary canines.
The deciduous canines were extracted, the midline diastema was closed,
and the impacted canines were brought into the arch.
A frenectomy was performed immediately after closure of the diastema.
Phase 3 Orthodontic treatment to align the canine in the arch and final finishing.
Progress intraoral photographs show the impacted teeth moving into the arch.

Treatment results
Posttreatment intraoral photographs and radiograph
• There was a dramatic improvement in the patient's smile.
• Facial balance was maintained despite extraction of the deciduous canines.
• The final study models show a bilateral Class II molar relationship and a Class
I canine relationship.
• Ideal overjet and overbite were achieved

CASE REPORT
Orthodontic management of bilateral maxillary
canine-first premolar transposition and
bilateral agenesis of maxillary lateral incisors:
a case report

Records at the age of 7 years and 6 months old
Initial casts of the patient at mixed dentition stage

Initial panoramic radiograph showing bilateral maxillary permanent
lateral incisors and second right lower premolar agenesis, and initial
bilateral transposition of upper canines and first premolars.

• After 2 years ,Pre-treatment facial photographs and intraoral views

Intraoral views during treatment

Final facial and intraoral photographs

Two-year follow-up facial photographs and intraoral photograph

Treatment options for missing
permnant teeth
• The treatment possibilities differ slightly for anterior and
posterior teeth.
• For missing posterior teeth, it is possible to:
1) Maintain the primary tooth or teeth
2) Extract the overlying primary teeth and then allow the
adjacent permanent teeth to drift
3) Extract the primary teeth followed by immediate
orthodontic treatment
4) Replace the missing teeth prosthetically or perhaps by
transplantation or an implant later.

For anterior teeth
• Maintaining the primary teeth is often less of an option due to
the esthetics and the spontaneous eruption of adjacent
permanent teeth into the space of the missing tooth.
• Also, extraction and drift of the adjacent teeth is less appealing
because anterior edentulous ridges deteriorate quickly.
• As with other growth problems, early evaluation and planning is
essential.

Treatment
• The treatment of congenitally missing maxillary lateral incisors is
challenging and complex, requiring very careful treatment
planning, communication with the patient, and often the
coordinated interdisciplinary efforts of the orthodontist,
periodontist, surgeon, and restorative dentist to achieve optimal
esthetic and functional results.
Advantages and Disadvantages of Treatment Options for Congenitally Missing Lateral Incisors Thomas E. Dudney, DMD

 Occlusion
 Alignment of teeth
 Patient age
 Remaining general growth of
the patient
 Crowding and spacing
 Alveolar bone thickness
 Facial profile
 Shape, color, and size of the
canines
 Lip length and position
 Gingival display, smile line,
buccal corridor; and black
triangles;
 Lip line
 Condition of adjacent teeth.
There are many factors that affect treatment options, such as:

The two main treatment options include either :
 Space Opening With Prosthetic Replacement
 Space Closure With Canine Substitution.
The ideal treatment is the most conservative option that satisfies
individual esthetic and functional requirements.

Space Closure Vs Prosthetic replacement
• There has been ongoing controversy in orthodontic and restorative
dentistry over the treatment of agenesis cases, especially of the lateral
incisors.
Occlusion :
• Restorative dentists were opposed to mesial movement of the maxillary
canine into the lateral incisor space, since this precluded the potential for
developing canine-protected occlusion, because it places the canine in
direct opposition to the mandibular lateral incisor.
• Stuart and Stallard, and D'Amico advocated canine-protected occlusion
in all dentitions.
• However, Nordquist and McNeill justified the mesial movement of canines
into lateral incisor space which provided many orthodontists with the
rationale for space closure.

• They stated that no difference existed in adequacy of occlusal
function between canine-protected and group function between
the two groups.
• Furthermore , studies have shown that two groups did not differ
significantly in respect to occlusal function and the prevalence of
temporomandibular dysfunction.
Periodontal health :
• Nordquist and McNeill also stated that treatment should be
designed to eliminate prostheses, which contributed to
accumulation of plaque and irritation.

Esthetics :
• Many orthodontic studies have shown that reshaping maxillary
canines to resemble lateral incisors greatly improves esthetics.
• However, even if the canines esthetically are recontoured, the
dentoalveolar arch curvature cannot be changed.
• The patient in full smile displays buccal corridor, since arch
circumference is diminished with closure of the lateral incisor
spaces.
• In the canine substitution case, the alveolar canine buttressing of
the canine roots is displayed anteriorly where the lateral incisors
should be, and the dental arch narrows distally. With space
closure, the arch form is condensed and constricted.

• Henns reported that the canine eminence is lost from its normal
position which canines were used as laterals as the eminence
accompanies the canine when it is moved.
• However, his study showed that the difference of the canine
eminence did not exceed a 1.5 mm when the mean arch form
recording of the Class I extraction group and the canine
substitution group were superimposed.
• According to his evaluation using the upper study casts, the poor
esthetic appearance of the canine eminence may have been
exaggerated.
The canine eminence : Angle orthodontics

Space Closure vs. Space opening

• In adults : Closing an old extraction site is likely to be difficult.
• After several years, resorption results in a decrease in the vertical
height of the bone, but more importantly, remodeling produces a
buccolingual narrowing of the alveolar process as well.
• When this has happened, closing the extraction space requires a
reshaping of the cortical bone that comprises the buccal and lingual
plates of the alveolar process.
• Cortical bone will respond to orthodontic force in most instances,
but the response is significantly slower.
• Even with skeletal anchorage, the space closure is likely to be quite
slow.
• Often, it is better judgment to open a partially closed old extraction
site and replace the missing tooth with a bridge or implant.
• This decision should be considered carefully in consultation
between the orthodontist and prosthodontist

Canine eruption in lateral
incisor space
• When teeth erupt or are moved, they bring alveolar bone with them.
• If a tooth is congenitally absent or extracted at an early age, a
permanent defect in the alveolar bone will occur unless another
tooth is moved into the area relatively rapidly.
• Carlson has shown that, after tooth extraction, the maxillary
anterior labiolingual width is reduced by 23% in the first 6 months
and, after 5 years, an additional 11% loss in ridge-width occurs.
After tooth extraction, the ridge-width will narrow by approximately
34% over 5 years.
• Because an erupting tooth brings alveolar bone with it, orthodontic
tooth movement can be used to create the alveolar bone needed to
support an implant to replace a congenitally missing tooth.

• For instance, if a maxillary lateral incisor is missing and a
prosthetic replacement is planned, it is advantageous to have the
permanent canine erupt mesially, into the area of the missing lateral
incisor, and then to move it back into its proper position toward the
end of the growth period.
• As the canine erupts into the lateral incisor space, alveolar bone will
form in a 2-4 mm area adjacent to the erupting tooth. It is therefore
important for a tooth to erupt in the eventual implant area.
As the permanent canine erupts
adjacent to the central incisor, its large
buccolingual width begins to develop
The canine is moved distally, leaving
behind an adequate buccolingual
width for implant placement.

• As the permanent canine is moved distally to create space for a
lateral incisor implant or bridge, an alveolar ridge is created.
• The labiolingual ridge width of bone over time in orthodontic
cases of canines moved distally was addressed by a study by
Kokich.
• The amount of bone loss was less than 1% over 4 years, compared
with the Carlson study of extracted teeth which showed 34%.
• Kokich concluded that, if the edentulous alveolar ridge was
created by orthodontic separation of two teeth, little resorptive
change will occur over time.

SPACE CLOSURE WITH
CANINE SUBSTITUTION

SPACE CLOSURE WITH CANINE
SUBSTITUTION
• In such a case, the maxillary canines would substitute laterals
and 1st premolar would substitute to maxillary canines.
Indication :
• Cases which may need all first or upper first premolar
extractions as a part of comprehensive orthodontic treatment for
the correction of superior protrusion/crowding/Class II molar
with missing laterals .
• The space requirements of the maxillary arch can be met with
missing laterals and premolar extraction need not to be carried
out in the maxillary arch.

Examples :
• Patients have a balanced or slightly convex facial profile an
angle class II malocclusion with no mandibular crowding
• Patients have angle class I malocclusion with mandibular
crowding necessitating extractions; and small canines that are
lighter in color

• Best when the incisors are slightly protrusive and the molars are
tending toward Class II in the posterior so that reciprocal space
closure can be employed between the anterior and posterior teeth
and moving the maxillary posterior teeth forward is easier .
orthodontic treatment of patient with missing lateral incisors (spacing) by Dr . Surendra Lodha

orthodontic treatment of patient with missing lateral incisors (spacing) by Dr . Surendra Lodha

Contraindications:
1. When the patients are full Class I .
2. Have a Class III tendency and the possibility exists of creating
an anterior crossbite with incisor retraction during space
closure.
However , TADs can help in these less than ideal situations.
Advantages of canine substitution
1. Natural teeth are biocompatible and preferable long term
2. The finished result is permanent,
3. Negating the need for future prosthetic replacement
4. Studies have shown that space closure using a premolar is
equally sound occlusally and preferable periodontally as canine
protected occlusion

Disadvantages :
1. A compromised aesthetics may be a major concern with such a
treatment plan.
2. Canine protected occlusion is not possible
3. The need for certain conditions to exist as previously stated
4. Adverse effects on dentoalveolar and facial esthetics as a result
of the canine prominence being moved mesially.
5. The tendency for space to sometimes reopen
6. Very large or dark canines that are difficult to reshape or bleach
to an acceptable shade and may require a restoration (i.e.,
porcelain veneer) to achieve the desired esthetic result

Finished treatment using the canines as lateral incisors
Patient with bilateral congenitally missing lateral incisors

The upper canines were modified prior to close spaces and replace
missing lateral incisors

Pretreatment and posttreatment photographs

Unilateral Space Closure
• Generally, unilateral orthodontic space closure in the anterior
region of the mouth is not recommended.
• There is probably a better chance of matching the existing teeth
with restorative solutions or substituting for both lateral incisors
than with reshaping the existing teeth on only one side.
• A unilateral missing lateral incisor might require the extraction
of the other lateral incisor prior to eruption of the canines to
maximize the drift pattern for ultimate space closure and
substitution, especially when the remaining primary incisor is
pegged , but generally the option to move the canines back into
their proper position exists prior to premolar eruption.
• These same considerations generally apply for the lower anterior
area, too, where one or two lateral incisors sometimes are
missing.

This patient's panoramic
radiograph shows that one
permanent maxillary lateral
incisor is missing and the other
peg-shaped.
Instead of opening or closing
space unilaterally the peg
lateral was extracted and
the teeth allowed to drift
and erupt.
The patient will now be treated
with bilateral space closure
or implants to improve
symmetry and esthetics.

Orthodontic considerations
• Before eruption of Canine
• After eruption of Canine

Before eruption of canine
• Sometimes the absence of lateral incisors causes a large diastema
to develop between the permanent central incisors.
• To maximize mesial drift of the erupting permanent canines, this
diastema can be closed and retained
• This technique enables the canines to erupt closer to their final
position and eliminates unnecessary tooth movement during full
appliance therapy.
• Later in the transition to the permanent dentition, the primary
canines should be extracted if they are not resorbing, so the
premolars can migrate into the canine positions and other
posterior teeth can move mesially and close space.

Intraoral photograph of a patient with that type of diastema, The
radiograph shows the unerupted canines in an excellent position for
substitution for the lateral incisors. The diastema has been closed to
obtain maximum mesial drift of the canines.

• Selective removal of primary teeth when permanent maxillary
lateral incisors are missing can lead to a shortened second phase of
fully banded treatment.
A and B, This patient had primary
Canines and primary first molars
extracted to maximize the mesial
drift of the permanent posterior
teeth.
C and D, This intervention resulted
in good tooth position that will
require little fixed appliance
therapy .

After eruption of Canine
Bracket Placement
• The lateral incisor brackets were bonded to the canines and the
canine brackets were placed on the first premolars.
• Before bonding the lateral incisor bracket on the canine, the
labial surface was reshaped for the bracket adaptation.
• It is necessary to position these brackets gingivally to permit the
re-contouring of the canines required for esthetics and function.
• The orthodontist should place the brackets according to gingival
margin height rather than incisal edge or cusp tip.

• To make the canine appear less curved and more like
a lateral incisor, the bracket was placed more distally in
the center of the canine rather than at the height of
contour.
• In addition, a canine bracket was placed on the first premolar in the
same mesiodistal position (more distally) in which it is placed on the
canine.
• The need for canines extrusion and premolars intrusion to adjust
the gingival level.
• Regarding canines mechanics, special attention should be given to
the torque that the canines should receive, namely lingual root
torque .

• However, to improve the interproximal contact points, offset
bonds (in-out) was needed between the central incisor and canine
Occlusal view of Canine Substitution

Reshaping of Canine and first premolar
• Post orthodontic occlusion would show maxillary canines having
substituted the lateral incisors with the first premolars as canines.
• The maxillary Canine ,which would then
substitute the maxillary lateral incisor, requires
accordingly reshaping and composite work of
the labial surface, cusp tip, proximal surfaces
and incisal edges of the canines for them to
mimic lateral incisors during treatment.
• The maxillary first premolar, which would then substitute the
maxillary canine, requires reshaping the mesiobuccal slope and
some reduction of the lingual cusp for functional contact with the
distal slope of the mandibular canine.

• The lingual cusps of the maxillary canines and first
premolars are recontoured to :
1. Eliminate traumatic occlusion of the mandibular lateral
incisors with the lingual surfaces of the canines.
2. Establish a balanced occlusion.

• After the teeth have been aligned and the canines reshaped,
there is frequently a need for restorative treatment to re-create
ideal lateral incisor color and contour.
• This may be accomplished with bleaching, composite resin, or a
porcelain veneer
A, After space closure. Note the unfavorable appearance of both canines
and the traumatically injured right central incisor (arrows).
B, Combination grinding of the canines and composite buildup on the
mesial aspects of the canines and the incisal edge of the central incisor.

Laminate veneers used to correct both the color and contour of teeth in canine
substitution treatment.
A,B Buildups on canines used
to fill in the space of
congenitally missing
maxillary lateral incisors
C,D Appearance after space
closure and laminate veneers
for the maxillary anterior
teeth.

(C) Clinical result of
orthodontic space closure
(A, B) Young female patient with
agenesis of maxillary right
lateral incisor and peg-shaped
left maxillary lateral incisor.
(D) Recontouring the canine to the lateral
incisor shape by grinding and making a
porcelain laminate veneer on the peg
lateral
(D, E, F), Final result.

Retention
• Bonded retainers using combination of thin multistrand flexible
wire (0.015- to 0.020-inch diameter) wire with wear-resistant
bonded composite can provide a very useful mode of retention to
prevent space reopening in a variety of postorthodontic situations
Long-term (up to 15 or more years)
Bilaterally missing maxillary lateral incisors
(the six-unit retainer is bonded in the occlusal fossa of the first premolars

Steps :
1. Interproximal reduction
2. Flattening the tip
Canine Reshaping

3.Flattening the facial surface
4. Reducing cingulum thickness

At that point, a lateral bracket can be placed on the canine during
orthodontic treatment.
6. If the gingival margin of the canine is visible, it can be brought
down by elongating the tooth and increasing the amount of
gingival reduction.
Recontouring of the gingiva over the first
premolar that becomes a substitution for
the canine also enhances appearance.
(with a diode laser)
5. Rounding the corners of the flattened crown
Final result

Esthetic Considerations

Esthetic Considerations
• When examining the esthetics of the anterior teeth and smile,
the clinician should be aware of the morphology of the gingival
contours, tooth contacts, tooth morphology, and tooth-size
problems.
• To obtain ideal esthetic results, worn incisal edges, tooth shape,
incisal contact, the contours of gingival margins, and black
triangles should be considered before starting orthodontic
treatment.

Tooth Proportions
The smile, of course, reveals the maxillary anterior teeth, and two
aspects of proportional relationships are important components of
their appearance:
 The tooth widths in relation to each other and,
 The height–width proportions of the individual teeth.

Width Relationships and the “Golden Proportion.”
• For best appearance, the apparent width of the lateral incisor (as
one would perceive it from a direct frontal examination) should
be 62%of the width of the central incisor, the apparent width of
the canine should be 62%of that of the lateral incisor, and the
apparent width of the first premolar should be 62%of that of the
canine.
• Ideal tooth width proportions when viewed from the front are one
of many illustrations of the “golden proportion,”
1.0:0.62:0.38:0.24, etc.

Height–Width Relationships :
• The width of the tooth should be about 80%of its height.
• Note that In reshaping canine , it is important to note both height
and width because if disproportions are noted, this allows a
determination of which is at fault.
• The longer teeth in this range appear more feminine, and shorter
teeth appear more masculine.

Gingival Heights, Shape, and Contour
The gingival height of the maxillary anteriors and the upper lip:
• The gingival margins of the canines should be coincident with the
upper lip, and the lateral incisors should be positioned slightly
inferior to the adjacent teeth.
• That the gingival margins should be coincident with the upper lip
in the social smile is generally accepted.
A, Equal gingival height is acceptable.
B, Ideal gingival height relationship.
C, Least desirable gingival height relationship

Gingival shape
• Refers to the curvature of the gingiva at the margin of the tooth.
• For best appearance, the gingival shape of the maxillary lateral
incisors should be a symmetric half-oval or half-circle.
• The maxillary centrals and canines should exhibit a gingival
shape that is more elliptical and oriented distally to the long axis
of the tooth .
• The gingival zenith (the most apical point of the gingival tissue)
should be located distal to the longitudinal axis of the maxillary
centrals and canines, while the gingival zenith of the maxillary
laterals should coincide with their longitudinal axis.

Connectors and Embrasures
• The contact points of the maxillary teeth move progressively
gingivally from the central incisors to the premolars, so that
there is a progressively larger incisal embrasure.
• Connectors that are too short often are part of the problem when
“black triangles” appear between the teeth because the gingival
embrasures are not filled with gingival papillae.

Tooth Shade and Color
• The teeth appear lighter and brighter at a younger age
and darker and duller as aging progresses.
• A normal progression of shade change from the midline
posteriorly is an important contributor to an attractive and
natural appearing smile. The maxillary central incisors
tend to be the brightest in the smile, the lateral incisors
less so, and the canines the least bright.
• The first and second premolars are more closely matched to
the lateral incisors , they are lighter and brighter than the
canines.
• canine may require bleaching, composite resin, or a
porcelain veneer if it will substitute the lateral incisor.

Smile Symmetry
• An asymmetric smile sometimes is a patient's major
concern. It is possible that this is due to more eruption
of the teeth or different crown heights on one side, and
if so, repositioning the teeth or changing the gingival
contours should be included in the treatment plan.
• The prosthetic replacement of the missing lateral
should mimic the other lateral

Lip Projection
• This adolescent patient presented with congenitally
missing maxillary lateral incisors and a large maxillary
diastema.
• Facially, she exhibited excessive lip fullness and
protrusion.

• Rather than close the diastema to make space for
placement of lateral incisor implants, the treatment plan
was to extract the mandibular first premolars, close the
space in the maxillary arch to treat her with cuspid
substitution, and retract the lower incisors resulting in
protrusion reduction to improve the balance of the lips and
chin.

Before and after treatment photographs

CASE REPORT
Treatment Planning Considerations in
Congenitally Missing Maxillary Lateral Incisor:
The Role of Orthodontics (In Orthodontic
Aspect)

• A 38-year-old Japanese female with missing the maxillary left
lateral incisor, she had facial symmetry with a convex profile .
• She had difficulty in biting and desired to improve her facial
esthetics.

• The maxillary dental midline was deviated to the left by 3.0 mm relative to
the facial midline.
• Due to the loss of the maxillary left lateral incisor there were severe
gingival marginal discrepancies between the maxillary left central incisor
and canine.
• The maxillary arch had mild crowding and the mandibular arch had severe
anterior crowding.

The cephalometric analysis revealed:
• The patient had a skeletal Class II (ANB= 6.4°).
• The maxillary incisors were slightly proclined (U1 to FH: 113.5°)
• The mandibular incisors showed normal inclination (IMPA: 94.1°).
• The upper and lower lips were slightly protrusive

Treatment options
1- Open space to replace the missing maxillary left lateral incisor.
• However, this treatment plan was not chosen because it can
procline the maxillary incisors and increase protrusive lips.
Furthermore, the patient was reluctant to undergo a restoration
for a single tooth space after orthodontic treatment.
2- Extract the maxillary right first premolar and mandibular right
second premolar which had restorations.
• However, the patient did not want to extract a tooth in the
mandibular arch.
3- The last treatment option was to extract the maxillary right
lateral incisor to correct the maxillary dental midline and slenderize
the mandibular incisors to relieve the crowding.
• The patient agreed to choose this treatment plan.

Treatment
1. The patient was referred to a general dentist for restorative
dentistry consultation as well as a periodontist for the
evaluation of the existing periodontal condition.
2. Orthodontic Treatment
3. On the maxillary arch, Essix retainer was delivered.
The patient was instructed to wear them 24 hours per day for
one year, and then night time only after one year.

Progress during orthodontic treatment

Final intraoral and extraoral photographs

Intraoral lateral close-up views before (A)and after (B) treatment.

6 years Posttreatment facial and intraoral photographs

CASE 2
A multidisciplinary treatment of
congenitally missing maxillary lateral
incisors: a 14-year follow-up case report.

Diagnosis
• A 12-year-old female patient in the late mixed dentition stage with
a chief complaint of spacing between the upper anterior teeth.
• Facial evaluation showed a mesofacial growth pattern, symmetrical
and proportional face without upper central incisor exposure at rest
and interlabial space of 0 mm.
• Analysis of the smile showed 100% exposure of the upper incisors,
generalized diastema, and midline sagittal plane coincident with
the medium line of smile .
• The patient had a convex facial profile and thin retruded lips .
A multidisciplinary treatment of congenitally missing
maxillary lateral incisors: a 14-year follow-up case report.

• Intraoral examination revealed an Angle Class II relationship of
molars and canines, 1 mm overjet, normal overbite, upper and
lower coincident midline in relation to the facial plane
• Maxillary arch showed generalized spaces in the anterior region
and missing lateral incisors .
• In the lower arch, complete permanent dentition was observed,
as well as the parabolic shape of the arch and diastema between
the incisors
• agenesis of maxillary incisors .

Intraoral photographs and panoramic radiograph

Treatment plan
• The proposed treatment plan was the space closure of the areas
corresponding to the missing upper lateral incisors, through
movement of the canines and the posterior teeth to mesial.
• After orthodontic correction, canine transformation /
reanatomization was performed

Treatment objectives
According to the diagnosis, the aims of treatment of this
clinical case included:
• space closure (the patient’s chief complaint).
• smile’s line and gingival level improvement.
• canines transformation/ reanatomization,
• lower arch midline maintenance.
• overjet and overbite maintenance.

Orthodontic ttt progress
• Upper arch was aligning and leveling with continuous arches
using Nitinol and also stainless steel arches to perform bending
and torque.
• Individualized canine extrusion and first premolar intrusion
during the mesial movement of these teeth were used.
• Finishing phase was accomplished with an stainless steel
braided 0.019x0.025-inch archwire to provide intercuspation.
• Hawley plate was used for retention after appliance removal.
• Lower arch was aligning and leveling with 0.014-inch, 0.016-
inch, 0.016x0.022-inch and 0.019x0.025-inch Nickel titanium
(NiTi).
• Intercuspation was achieved with stainless steel braided
archwire 0.019x0.025-inch.
• Fixed canine-to-canine retainer was bonded immediately after
appliance removal .

Treatment progress : Intraoral photographs showing full fixed appliances .
Upper stainless steel arch performing bends (individualized canine
extrusion) to adequate placement of gingival margins

Treatment results
• This case’s completion has kept the upper molars in an Angle
Class II and canines were masked cosmetically as lateral incisors
with restorative dentistry procedures.
• The panoramic radiograph confirms stability of the closed spaces.

Post treatment intraoral photographs showing proper crown torque of
mesially relocated canines and premolars and an optimum level for the
marginal gingival contours of the anterior teeth

follow-up
14-year follow-up involving orthodontics and restorative dentistry:
Facial photographs showed a good facial profile and proportional esthetic face
The analysis of smile showed 100% exposure of the upper incisors with midline
sagittal plane coincident with the medium line of smile .

Intraoral photographs revealed optimal and stable occlusion with normal overbite and overjet and
maintenance of upper and lower arch shapes .
Panoramic X-ray showing ideal dental axial inclinations confirming the stability of the closed space

SPACE OPENING
• Indications :
• In children with normal profile and class I occlusion, arch
alignment is achieved with a class I molar and canine relation
and regaining the space of laterals.
• Class III malocclusion and retrognathic profile
• Contraindications :
• Class II malocclusion cases with mesial eruption of the canines
into the lateral incisor position, extensive distalization of the
buccal dentition is required to create the mesial-distal space and
to provide an alveolar ridge for esthetic lateral incisor pontic
placement.
• The second molars have to be distalized into a Class I position,
the first molars, the second premolars, the first premolars and,
finally, the maxillary canines are distalized into a Class I
occlusion, to provide the mesial-distal space necessary for
achieving ideal restorative dentistry

Patient with anterior crossbite The correction of anterior crossbite
After orthodontic treatmentFinal view

Retainer in place with plastic
replacement teeth.
Space was developed for replacement teeth
Final result

Prosthetic replacement options :
• Removable partial dentures
• Fixed bridge
– Conventional Full-coverage fixed bridge(porcelain fused- to-metal
[PFM], all-ceramic, or resin based)
– Cantilever bridge
– Partial-coverage fixed bridge
 Metal framework [Maryland bridge],
 Ceramic framework,
 Fiber-reinforced resin with porcelain veneer[s]
 Resin bonded bridge
• Dental implant and fixed restoration

Orthodontic Treatment
• Orthodontic intervention often is required prior to the restorative
treatment phase to address unfavorable spacing or occlusal issues and to
optimize the position of the teeth.
• It is recommended that the restorative dentist evaluate the patient prior
to orthodontic treatment and close to its completion (finishing stage).
• Information on the restorative treatment may influence the orthodontic
result, and in some cases, minor modifications prior to the removal of
the brackets will improve the restorative result.
Treatment of Congenitally Missing Lateral Incisors with
Resin-Bonded Fixed Partial Dentures

Space regaining
• With Fixed appliance or removable as Finger springs according to
the case
• Finger Spring can be used to regain space in the anterior
segment which has been partially lost due to migration of
neighboring teeth in children with missing lateral incisors when
canine tends to erupt mesially.
Retainer with finger spring for mesiodistal
movement of abutment teeth

Biomechanics in space closure and space opening

Determination of appropriate
spacing
4 methods :
• Golden proportion
• Contralateral lateral incisor
• Bolton analysis
• Wax-Up
Managing Congenitally Missing Lateral Incisors.
Part II: Tooth-Supported Restorations

Golden proportion :
• Since the maxillary teeth are positioned
along an arc, each tooth should be 61.8%
wider than the tooth distal to it.
Contralateral lateral incisor :
• However, this method is not appropriate if the contralateral tooth
is missing or peg shaped.
Bolton analysis :
•
Sum of mandibular six teeth
Sum of maxillary six teeth
= Bolton ratio (~ 0.78)
Diagnostic Wax-Up
• The most predictable method
• If the anterior and posterior teeth are set in their ideal functional
and esthetic relationships, the remaining space should be ideal
for a lateral incisor restoration. Generally this width ranges
from 5 to 7 mm.
• Digitized dental casts (Ortho-CAD system) is the modern
alternative. Managing Congenitally Missing Lateral Incisors.

Diagnostic wax-up
• A ,The maxillary canine should be positioned in the embrasure
between the mandibular canine and first premolar.
• This allows for proper canine disclusion.
• B, The maxillary central incisors should be positioned in the
appropriate overbite and inclination to achieve ideal esthetics.
• The space that remains is used for the lateral incisor

Orthodontic Considerations :
1) Midline :
• In creating the proper mesial-distal space for lateral incisor restoration,
the clinician should properly position the central incisors with respect to
the midpoint of the cupid’s bow of the philtrum of the upper lip and
upper face, and to have maxillary and mandibular midlines coincident.
• Obviously, the more important of these two is the maxillary midline to
the upper lip and face.
2) Root Position
• Radiographs are then taken of the created ridge and root positions of the
central incisors and the canines.
• The root position must be evaluated by both the orthodontist and the
surgeon in implant cases or restorative cases.

Soft Tissue Considerations
in the Pontic Area
• Ideal gingival contours are the natural framework for any dental
restoration and require special attention.
• The amount of remaining hard and soft tissue dictates subsequent
treatment to create a natural appearance.
Soft Tissue Contouring through
1) Surgical gingivoplasty.
2) Non-Surgical gingivoplasty (Soft tissue contouring with temporary
restoration )

Non Surgical gingivoplasty :
• An ideal pontic site might be developed with a fixed temporary
restoration and a pontic specifically shaped for this site.
• However, during fabrication of a fixed partial denture, the most
viable temporary restoration is often a removable appliance.
• However, no surgery is needed to create an ovate pontic receptor
site if the patient meets the following criteria.
Indications
1. Slight-to-moderate horizontal deficiencies
2. Slight or no vertical deficiencies
3. Gingival thickness over bone of at least 2 mm
4. Mesio-distal space available within normal ranges
5. Patient willing to comply with a removable appliance for a few
weeks.
6. If the patient had a gingival deficiency, avoid any gingivectomy
procedure at the pontic receptor site and rather to guide the soft
tissue into a more ideal shape without surgical intervention.

Contraindications :
• Severe ridge defects .
• The lack of new tissue “created,” since there is no augmentation
of the ridge.
Advantages :
1. Creates a pontic receptor site almost as ideal as with surgical
augmentation.
2. This modified technique may satisfy the functional and esthetic
demands of today’s patients.
3. It is a minimally invasive and very conservative treatment
approach.
4. Creates an opportunity to increase the apparent size of the
papillae, to give the appearance of additional facial bulk of
tissue, and to form a gingival- tooth interface that resembles
that of a natural tooth.

Retention appliances
• Used for :
Temporary Restoration and Soft Tissue Contouring.
• Pontics may be included in the retainer design to enhance
aesthetics and retain the edentulous area(s) during the transition
from fixed appliances to prosthetic replacement of missing teeth.
Maxillary circumferential retainer
with pontic to replace missing right
central incisor.
Hawley retainer with pontic to
replace missing left lateral incisor

• This denture tooth is selected in the appropriate shade and mold,
and was then customized to resemble the contralateral tooth.
• The tissue side of the pontic is contoured in a ridge-lap shape to
avoid initial impinging of the tissue.

• Lingual bonded segmental wires are used to prevent the teeth
from drifting into the edentulous areas, and a “flipper” with
pontic (s) made to fit over the bonded wires is worn during the
day for aesthetics
Flipper in place for aesthetic replacement of maxillary right lateral incisor.
Note the use of pink acrylic gingivally to blend into oral mucosa.

• After placement of implants, the retainer can be relieved in the
gingival area to allow maintenance of dental aesthetics while
avoiding tissue impingement during the osseointegration stage.
• The clinician may adjust the retainer after completion of the
prosthetic phase simply by removing the pontic and recontouring
the palatal acrylic to fit the final restoration.
Clear retainer with the maxillary
right lateral incisor pontic
• A clear removable retainer with
pontic (s) held in place within the
plastic is also typically made to
be worn at night or for use in
emergency situations if the
regular retainer is lost or broken.
• The clear retainer is stronger and
acts as a nightguard to prevent
breakage of the pontic from
grinding or clenching during
sleep.

The edentulous alveolar ridge had a deficiency in the
gingival architecture
A thermoformed clear acrylic splint (Essix appliance) with a denture
tooth in the position of the left lateral incisor was used as a retainer with
an additional goal of “orthodontically” shaping the underlying gingiva.

Prosthetic replacements
• After the patient had successfully completed orthodontic
treatment.
• It is important to keep in mind that the planned pontic must
mimic the contours of the right lateral incisor.
• Reasonable symmetry was a goal for achieving an overall esthetic
smile.

Removable Partial Dentures
• Historically, options for space opening with prosthetic
replacement were limited to removable partial dentures and
conventional fixed bridges.
• Neither option was very appealing and in the past made space
closure with canine substitution a more attractive alternative.
Advantages :
• Conservative than fixed bridge
Disadvantages:
• Their bulky and cumbersome Design
• Difficult to achieve esthetic results
• Patients disliked wearing them

Bonded Single-Tooth Replacements
• The use of bonded bridgework (three-unit or cantilever) has
become accepted as a semi-permanent procedure.
• Failure rates over a 10-year period may be in the 30% range,
particularly if cases are selected to allow no or only limited
occlusal contact on the restoration.
Advantages
• A cheaper, simpler, and perhaps more durable alternative than
the cast variants for anterior tooth replacement .
Disadvantages
• Higher failure rates have been experienced with the presence of
occlusal contact, particularly in children.

Four-wire version of the resin-bonded bridge, where the two braided
wires run continuously through the pontic
• Note the attempts to achieve clean interdental conditions.
Three-wire design for single tooth replacement of a missing right lateral incisor

A resin-bonded fixed partial denture
(Maryland bridge)
Description:
• The first attempt at a conservative fixed restorative option was
the Maryland bridge,
• Has metal wings that bonded to the lingual surface of the central
and canine.
• Long-term success of resin-bonded fixed partial dentures depends
on the preparation design, fit, metal and tooth-surface
pretreatment, and luting agent.
Advantages :
• minimally invasive (very conservative ).

Disadvantages:
1. Compromised esthetics from the metal wings showing through
translucent enamel
2. The inability of the rigid metal wings to flex with the slight
mobility of the anterior teeth, often leading to debonding .
3. High incidence of failure especially in deep overbite cases.
4. Complicates shade matching even more because of the shade
change that generally occurs on the abutments at cementation
due to the cast-metal lingual retainers that impart a gray
appearance in the incisal third. Even if the pontic matches
perfectly at try-in, once it has been luted the result may be
disappointing.

Orthodontic Considerations
Position of the abutment teeth :
First, A shallow overbite decreases the amount of lateral forces on
the abutment teeth as well as maximizes the surface area
available for bonding the retainers.
A shallow overbite also allows the retainer extensions to be carried
farther incisally without the abutment teeth requiring
preparation. (Fig B)

• Second , The direction of normal occlusal forces on proclined
incisors creates more of a tensile force at the bond interface,
whereas occlusal forces on upright incisors create more of a shear
force at the bond interface
• Based on theoretic physics principles, an object loaded with a
shear force can withstand approximately 40% more load prior to
failure compared with the same object loaded with a tensile force
A, Occlusal forces on proclined incisors create a more
tensile type of force at the bond interface.
B, The same occlusal forces on teeth that are upright
generate a more shear type of force at the bond interface.

Open space of the lateral incisors and prosthetic replacement of lateral incisors

THE FIBER-REINFORCED RESIN-BONDED
BRIDGE
• Referred to as the Encore bridge
• Based on the same principle as the Maryland bridge.
• Instead of metal wings, this type of bridge incorporates
laboratory-processed composite resin with fiber reinforcement in
the form of a lingual framework with a ceramic veneer bonded to
the facial of the pontic (ceramic overlay on the pontic)
• This design ensures long-term esthetics and vitality of the
restoration.

Advantages :
1. The fiber-reinforced resin framework readily bonds to enamel
and dentin
2. Has the strength and elasticity to resist fracture and debonding,
even in the presence of slight mobility of the anterior teeth.
3. The material is tooth-colored, hence the problem of discoloration
and graying of enamel caused by metal show-through is
eliminated
4. Less invasive than conventional three-unit or even two unit
canine cantilevered fixed bridges
5. In cases where patients desire a more comprehensive smile
enhancement procedure in addition to replacing the congenitally
missing lateral incisors, this technique works well because
porcelain veneers can be placed on the natural teeth as well as
the pontics of the resin frameworks, thus giving the restorative
team control of the size, shape, position, and color of the
restorations in the final smile

Disadvantages :
1. Require some tooth preparation on the lingual and
interproximal surfaces of the abutment teeth.
2. High failure rate when subjected to excessive lateral forces (not
recommended for patients with a deep overbite relationship.)
3. Have to be remade several times over the lifetime of a young
patient,
4. The possibility of connector site fractures
5. Material delamination, debonding still exists
6. Requires placement of a porcelain veneer on the facial of the
pontic, which is a very sensitive technique that significantly
increases operative time.
Contraindications :
• patients with a deep overbite relationship

Bilateral congenitally missing lateral
incisors
Fiber-reinforced resin-bonded bridges
and ceramic veneers on the pontics
and natural teeth restored with
veneers

CANTILEVERED FIXED PARTIAL
DENTURE
• Given its root length and crown dimensions, the canine is an
ideal abutment for a cantilevered fixed partial denture.
• The cantilevered fixed partial denture can be designed using
either a partial-coverage or a conventional full-coverage retainer.
• If the facial esthetics of the canine abutment does not need to be
altered, the most conservative cantilevered restoration uses a
partial coverage preparation .
• If the canine abutment requires a change in the facial contour to
enhance the esthetics, a conventional full-coverage preparation
can be done to support the cantilevered lateral pontic.

• The success of this type of restoration is dependent on the ability
to control the occlusal contacts on the pontic. It is important that
all contact in excursive movements be removed from the
cantilever.
The restoration of the cantilevered fixed partial dentures replacing the lateral incisors.
Connective tissue grafting was done to improve the pontic – soft tissue relationship.

Conventional Full Coverage
Fixed bridges (PFM , All-Ceramic)
Indications :
• Because they require an amount of tooth reduction their use
should be limited to situations where a conventional bridge
already exists or the condition of the abutment teeth (i.e., wear,
caries, fracture, etc.) would dictate a more aggressive
preparation.
Advantages:
• More comfortable and esthetic than removable partial dentures
• With today's materials, offer excellent results from esthetic and
functional perspectives.

Disadvantages
• Gross reduction of healthy tooth structure , So contraindicated in
young patients ( large pulp size ).
• The required connector dimension is limiting in many patients.
• An overbite that is equal to or greater than average or tooth size
that is equal to or smaller than average (which is common in
patients who are congenitally missing laterals) will often
contraindicate a large connector

The inclination and angulation of abutment teeth :
For proper path of insertion.
• When evaluating the patient’s teeth from a frontal perspective, the
long axis of the central incisor and the labial surface of the canine
must also be parallel for proper tooth preparation ( Fig A).
• If the inclination of the canine is incorrect, the restorative dentist has
to over-prepare the teeth to achieve the proper line of draw (Fig B)

• When evaluating a patient from a lateral perspective, the long
axis of the canine and labial surface of the central incisor should
be parallel. (Fig A)
• An increased proclination of the central incisors often makes it
difficult for the restorative dentist to conservatively prepare
these teeth to receive a bridge restoration. (Fig B)
• This may ultimately weaken the abutments or impinge on the
pulp chamber.

The faciolingual position of the abutment teeth :
• relates to palatal tooth preparation and joint size.
• The orthodontist can leave an excess overjet (approximately 0.5
to 0.75 mm )to help increase the buccolingual dimension of the
joint and allow more definitive facial embrasures without
jeopardizing the strength of the joint.
• Any excess space remaining on the adjacent unrestored teeth can
be closed with direct composite bonding.
• it allows a more conservative palatal preparation, which can be
important in patients with thin teeth.

CASE REPORT
Treatment of Congenitally Missing Lateral
Incisors with Resin-Bonded Fixed Partial
Dentures

Case presentation
• A 17-year-old healthy female had a congenitally missing
maxillary left lateral incisor.
• The maxillary right lateral incisor was slightly undersized and
malformed, although not enough for it to be classified as a peg
lateral.
• Orthodontic treatment was complete, and the patient was using a
Hawley-type retainer with a denture tooth attached for the
prosthetic replacement of the left lateral.
• Treatment of Congenitally Missing Lateral Incisors with
• The patient was unhappy with the
appliance and wanted a
permanently fixed solution.
• Records were taken, and the
diagnosis and treatment plan were
completed.

• This particular patient had successfully completed orthodontic
treatment.
• Orthodontic intervention often is required prior to the
restorative treatment phase to address unfavorable spacing or
occlusal issues and to optimize the position of the teeth.
• The patient was using a Hawley-type retainer with a denture
tooth attached for the prosthetic replacement of the left lateral.

Temporary Restoration and Soft
Tissue Contouring
• The edentulous alveolar ridge had a deficiency in the gingival
architecture , and though surgical ridge augmentation was the
most appropriate procedure, the patient declined it.

• A thermoformed clear acrylic appliance adapted to the six anterior
teeth (Essix, Raintree Essix Inc, Metairie, LA, USA) with a denture
tooth in the left lateral incisor position was fabricated to replace the
Hawley retainer with an additional goal of reshaping the underlying
gingiva.
• Since this patient had a gingival deficiency, it was decided to avoid
any gingivectomy procedure at the pontic receptor site and rather to
guide the soft tissue into a more ideal shape without surgical
intervention.

Shaping of the pontic receptor site
After about 1 week of wearing the Essix appliance, a narrow extension made of
composite— the “site former”—was added to the base of the pontic
• This initial shape was modified every few days to guide the tissue
primarily toward the facial aspect.
• The patient was instructed to remove the appliance for cleaning
• only and to replace it within a few minutes in order to avoid
tissue relapse.

After adding increments of composite twice a week for a total of 6
weeks, the pontic receptor site had reached its desired shape.

Restorative Treatment
• Since the patient was not satisfied with the original shade of her
natural teeth, home bleaching was performed until she was
satisfied with the shade.
• A direct composite restoration was then fabricated to improve
the shape of the small, misshapen right lateral incisor.

Tooth Preparation
Intraoral view of the final preparations of the abutment teeth (the maxillary left
canine and central incisor) for a resin-bonded fixed partial denture.

Fabrication of the Final Restoration
Completed prosthesis, lingual and buccal views.

Postoperative (2.5-year follow-up) views:
contralateral side, radiograph, and resin bonded
fixed partial denture replacing the maxillary left
lateral incisor.

Preoperative view of A 17-year-old female.
With a Hawley retainer with a denture tooth
attached for the prosthetic replacement of the
congenitally missing Maxillary left lateral after
orthodontic treatment is complete.
Post-operative view and
radiograph 2.5-year follow-
up of the resin bonded
bridge .
the pontic mimic the contours of the right
lateral incisor.
A thermoformed clear acrylic
splint (Essix appliance) with a
denture tooth in the position of
the left lateral incisor

THE SINGLE-TOOTH IMPLANT
• A more recent treatment option that currently is recommended
Advantages :
1. Predictability and long-term success rates
2. Obvious restorative choice when teeth adjacent to the space are
healthy, of normal size and shape, and unrestored (the ability to
leave the adjacent teeth untouched)
3. Provide a functional stimulus to help preserve bone and prevent
resorption.
4. Conservatively satisfy the esthetic, functional, and biologic goals
of treatment

Dental implant does not require modifying the adjacent teeth (central incisors and
canine), whereas the bridge requires "prepare" or change some of the teeth
adjacent to the edentulous space to receive crowns

Disadvantages
1. Require very careful case selection.
2. Require a diligent and well-coordinated interdisciplinary
approach.
3. In addition to site development, space requirements, and age
restrictions because of the necessity for growth completion as
conditions that must be met for successful treatment
4. The potential for esthetic failure as a result of gingival darkening,
exposure at the margin from gingival recession
5. Incisal edge and gingival discrepancies from long-term facial
growth and vertical movement of teeth
6. Difficulty of matching natural tooth color and translucency with
an implant crown

Contraindications of implants
1. Medical contraindications
2. Young age (growth incomplete)
3. Unfavorable root proximity and/or root alignment , especially
after orthodontic treatment
4. Deficient alveolar ridge requiring significant augmentation
5. Smoking habits
6. High occlusal stress
7. Severe occlusal discrepancies

• However, when choosing the single-tooth implant as a restorative
option, several factors must be taken into account such as growth
considerations, space requirements, and site development.
Growth Considerations:
• Because an implant acts essentially like an ankylosed tooth, any
vertical alveolar growth and eruption of teeth would cause a
discrepancy between the gingival margin of the natural tooth and
the implant.
• Implant placement should occur only after growth has been
completed.
• It has been suggested that neither chronological age nor hand-
wrist radiographs are reliable enough to make that
determination.
• Instead it would be best to compare superimposed cephalometric
radiographs taken at 1-year intervals until no growth changes
are detected
• This is usually around 14-15 years of age in girls and 16-17 years
of age in boys.

Space requirements
1. The tooth width requirements for mesiodistal spacing.
2. The amount of space between the roots is critical to successful
implant placement
3. The alveolar width in a buccolingual direction.
The tooth width requirements for mesiodistal spacing
• Prior to the removal of orthodontic appliances, the restorative
dentist should review the progress of treatment to make sure that
adequate space has been created.
• A Maryland bridge or a pontic on a retainer can serve as an interim
prosthesis until the completion of growth.
The amount of space between the roots
• Orthodontic intervention usually is necessary to achieve not only the
amount of inter-radicular space needed( 5mm minimum ), but also
the proper root angulation.
• The root up-righting in the region of the missing tooth can be
monitored with a periapical radiograph using the long cone
technique

The amount of space has been increased to 6 mm on each side.
Plastic teeth on the archwire (G) and on her retainer (H) are
now more proportional to the central incisors and the occlusion still interdigitates properly
Patient with bilateral missing lateral incisors and the amount of
space is 3 mm on the right and 4 mm on the left
Orthodontic treatment was done with the goal of creating more space for implants.
However, the interproximal surfaces of the canines and central incisors
were already flat (A, B). Therefore, enamel was removed from the mesial and distal surfaces
of the maxillary first and second premolars to create more space
Vincent G. Kokich. Maxillary Lateral Incisor Implants. J Oral Maxillofac Surg 2004.

Vincent G. Kokich. Maxillary Lateral Incisor Implants. J Oral Maxillofac Surg 2004.
(G) The roots apart to create space for an implant.
(H) With sufficient space the restorative dentist can create ideal papillary aesthetics
adjacent to the implant crown that was stable after 5 years (I).
(A) This patient was congenitally missing the maxillary right lateral incisor .
(B) After the maxillary arch had been aligned , no space was present for an implant.
(C) A coil spring was used to open space.
(D) the roots of the canine and central incisor moved closer together .
(E) Therefore, the orthodontist placed plastic tooth in the archwire to maintain the space for
the crown

The alveolar width
• The alveolar width in a buccolingual direction must be adequate for
implant placement.
• It is necessary to graft or augment the alveolar ridge before an
implant can be placed.
• It has been suggested in the literature that by allowing or guiding
the eruption of the canines into the lateral position and
orthodontically moving them to their natural position, the necessary
amount of buccolingual
alveolar thickness for implant
placement can be achieved
naturally, without the need to
perform any ridge augmentation.

• Although not completely understood, it has been shown that very
little, if any, resorptive change in alveolar bone width is observed
when space is opened orthodontically compared with the decrease
in alveolar ridge width after extraction of maxillary anterior
teeth.
• However, a disadvantage of orthodontic canine distalization for
implant site development is the potential for loss of arch length
when the canines are allowed to erupt mesially

Site development
• One interesting finding in that longitudinal study was the
development of the palatal height.
• A continuous slow increase in this distance seems to indicate an
important role in the tooth eruption mechanism
• This knowledge is of importance in explaining the infra-position
of an implant-supported crown as a continuous eruption of its
adjacent teeth

Palatal height (mm) in females (red) and males (blue), followed from 5
to 31 years of age; mean and standard deviation for each recording.
(From Thilander B: Dentoalveolar development in subjects with normal occlusion: A
longitudinal study between the ages of 5 and 31 years, Eur J Orthod 31:109, 2009.)

A patient with an implant-supported crown (arrow) replacing the congenitally
missing upper right lateral incisor.
B, Continuous eruption of the teeth adjacent to the implant from 16 to 24 years
resulted in 1.6 mm of infraocclusion of the implant supported crown (arrow).
(Adapted from Thilander B et al: Orthodontic aspects of the use of oral implants
in adolescents: A 10-year follow-up study, Eur J Orthod 23:715, 2001.)

Root angulation:
• Problems with inadequate space between the root apices are
generally due to improper mesiodistal root angulation.
• After the canine erupts adjacent to the central incisor, the
appropriate amount of coronal space must be opened for the
missing lateral incisor.(Fig A)
• When the space is opened, the crowns of the central incisor and
canine are tipped apart.(Fig B)
Part III: Single-Tooth Implants

• Therefore, it is important to take a periapical
radiograph of the edentulous area prior to
removing orthodontic appliances to confirm the
ideal root position and adequate spacing for a
future implant placement.
In certain patients it may be impossible to achieve acceptable
interradicular spacing using orthodontics, even though the coronal
spacing may be ideal.
This patient had previously been
restored with resin-bonded fixed partial
dentures that subsequently failed.
B, Inadequate interradicular
spacing for implant placement necessitated
the need for orthodontic treatment

• An example would be a patient with a Class III tendency
malocclusion requiring proclination of the maxillary incisors .
• As the maxillary incisor crowns are aligned, they are tipped
labially.
• Their roots tend to converge toward
each other resulting in a “wagon-wheel” effect.

• When the maxillary anterior teeth are at the proper inclination,
there should be adequate interradicular space for implant
placement. (Fig A)
• When the maxillary incisors are proclined, the root apices
converge. This often creates root proximity problems that make
implant placement difficult, an alternate restorative option is
required (Fig B)

A few months, the roots are parallel and there is enough space for placing dental
implants in edentulous spaces
A panoramic radiograph confirms the wrong position of the central incisors . and
implants added as simulation.
The blue dotted line represents the ideal position that should be central.

INTERIM TOOTH REPLACEMENT
AFTER ORTHODONTICS
• If implants cannot be placed until facial growth is complete,
• One option is to use a removable retainer with a prosthetic tooth
• Care must be taken to ensure that the retainer is supported by
the adjacent teeth rather than solely resting on the soft tissue in
the edentulous area.
• This helps avoid excessive pressure and inflammation of the
ridge and papillary areas.
• If it will be years before growth is completed and an implant can
be placed, Resin-bonded fixed partial denture is a more long-term
provisional restoration .
• This type of restoration keeps excessive pressure off the ridge
and can help support the papilla.
• In addition, it can be removed when it is no longer needed with
minimal alteration of the adjacent teeth.

Case
A-C , Pretreatment intraoral photographs of a 14-year-old female
who has congenital absence of #7 and #10.
• D–F, Posttreatment intraoral photographs of 16.5-year-old female above
in which decision was made to “reverse” the anterior arch collapse and
to move canines into their correct anatomical and functional position.

• G, Pretreatment smile H, Posttreatment smile illustrating
dental, occlusal, and alveolar stabilization following implant
replacement with crowns for teeth #7 and #10.
• I, Posttreatment panoramic radiograph illustrating properly
positioned implants allowing long-term health and function.

• To preserve the alveolar bone and minimize bone resorption, mini-anchor
screws are inserted temporary lateral incisors position (arrows).
Case 2
• Male of 14 years with an absence of upper lateral incisors.
• The spaces were opened in orthodontics for replacing missing teeth with
dental implants that can only be posed in several years.

(D) X-ray showing the mini-anchor
screws in place.
(C) Temporary crowns are attached to mini-anchor screw.
(E) The mini-screws used to support a temporary
crown are different; they have a central portion
capable of receiving the attachment of a crown

CASE REPORT
Replacement of Congenitally Missing Lateral
Incisor Using a Metal-Free, Resin-Bonded
Fixed Partial Denture: Case Report

Diagnosis
• A 22-year-old woman with congenital absence of the maxillary left
lateral incisor was referred to clinic.
• A clinical examination revealed that the maxillary left permanent
canine had undergone ectopic eruption and the deciduous canine
had not exfoliated .
• The periodontium of the intact abutment teeth was healthy.
• The maxillary first molars were in Class I relationship on both
sides. Crowding of the teeth was minimal in both the upper and
lower arches
Replacement of Congenitally Missing Lateral Incisor Using a Metal-
Free, Resin-Bonded Fixed Partial Denture: Case Report

Treatment plan
• Treatment without extraction of any permanent teeth was
planned.
• Extraction of the remaining deciduous canine,
• Distalization of the left permanent canine into its proper
position
• Placement of an implant-supported all-ceramic crown in the
position of the missing lateral incisor.

Treatment
After extraction of the remaining deciduous
tooth, the upper canine was retracted with
a force of 150 g by fixed orthodontic
appliances.
As soon as retraction of the maxillary canine
had been achieved, the angulations of the
maxillary left central incisor and left canine
were adjusted to avoid any contact between
the implant and the roots of these 2 teeth.
The dimensions of the buccal and palatal
bones and the height of the alveolar ridge
were sufficient for the planned treatment.

Implant was inserted
.
While the crown was being fabricated, it
was discovered that the expected bony
integration had not been achieved, and the
implant was removed.
After removal of the implant ,the defect
area was restored with hydroxyapatite graft
Material.
Implant site after removal of the implant.
Implant site after healing period

Four months after bone grafting, bone volume
was insufficient to allow an implant-supported
all-ceramic crown as shown .
• Therefore, to increase the bone volume, autogenous block bone grafting
was planned.
• This surgery would have been the third procedure and would have
substantially lengthened the overall treatment time, but when the
procedure was described to the patient, she was unwilling to proceed.
• The option of fabricating an RBFPD rather than an implant-supported
prosthesis was presented

An all-ceramic RBFPD was selected as it would be more esthetically
pleasing and more conservative than a metal RBFPD or an all-ceramic
FPD without resin bonding
12 months follow-up
Final result

References
• Contemporary Orthodontics , William R Proffit ,5th edition
• Orthodontics Current principles and techniques , (Graber Vanarsdall Vig ,
5th edition )
• Orthodontics Diagnosis and Management of Malocclusion and Dentofacial
Deformities
• Advantages and Disadvantages of Treatment Options for Congenitally
Missing Lateral Incisors Thomas E. Dudney, DMD
• Treatment Planning Considerations in Congenitally Missing Maxillary
• Treatment of Congenitally Missing Lateral Incisors with Resin-Bonded
Fixed Partial Dentures
• Managing Congenitally Missing Lateral Incisors. Part I: Canine
Substitution
• Managing Congenitally Missing Lateral Incisors. Part II: Tooth-
Supported Restorations
• Managing Congenitally Missing Lateral Incisors. Part III: Single-Tooth
Implants
• Replacement of Congenitally Missing Lateral Incisor Using a Metal-
• Palatally impacted maxillary canine with congenitally missing lateral
incisors and midline diastema Case repost July 2013 Vol 144 Issue 1
,AJODO

Congenitally Missing Maxillary Lateral Incisor

Congenitally Missing Maxillary Lateral Incisor

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