2.diagnosis restoration of worn dentition

POSTGRADUATE DEPARTMENT OF CONSERVATIVE
DENTISTRY AND ENDODONTICS
SEMINAR TOPIC:-
RESTORATIVE MANAGEMENT OF WORN
DENTITION - II
(Assesment & role of occlusion in tooth wear)
Presenter- Ashish Choudhary
PG student
UNDER GUIDANCE OF :-
Prof. Dr Riyaz Farooq (HOD)
Dr Aamir Rashid (Asst. Prof.)
Dr Fayaz Ahmed (lecturer)

CONTENTS
 PATIENT’S HISTORY
 EXAMINATION OF WEAR’s PATIENT
 DIAGNOSIS
 MEASUREMENT OF SEVERITY & PROGRESSION OF WEAR
 DILEMA OF OCCLUSION
RESTORATION OF WORN DENTITION-II
( Assesment & Role of Occlusion in tooth wear)

 MOUNTING CAST (Articularors & Facebow transfer)
PROBLEM OF SPACES (increasing Vertical Dimension)
 RESTORATION OF WORN DENTITION
 REHABILIATION OF WORN DENTITION
 MAINTENANCE
 CONCLUSION
REFERENCES
RESTORATION OF WORN DENTITION-III
( Treatment Planning)

TOOTH WEAR’S MULTI-FACTORIAL
AETIOLOGY
ABRASION
ABFRACTION
ATTRITION
EROSION
BRUXISM

PATIENT’S HISTORY*
The successful management of any case of
tooth wear is based on deriving an accurate
diagnosis, having a clear understanding of the
basic principles of occlusion, and a good
working knowledge of available materials and
techniques to treat such cases using both
active and passive means
*BDJ;2012 ; VOLUME 212 NO. 1
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The formulation of a comprehensive
treatment plan relies on an accurate history
and examination of the patient
 The management of tooth wear depends
to an extent on the ability of the patient’s
understanding of the condition in order to
provide information to allow the clinician to
arrive at a differential diagnosis
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
BDJ;2012 ; VOLUME 212 NO. 1

According to Holbrook and Arnadottir, in order to
prevent or reduce non-carious destruction of tooth
substance it is important to:
• Recognise that the problem is present
• Grade its severity
• Diagnose the likely cause or causes
• Monitor progress of the disease in order to
assess the success, if any, of any preventative
measures
Br Dent J 2003; 195: 75–81
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The accuracy and importance of the chief complaint
must be first evaluated
CHIEF COMPLAINT
 Common complaints associated with dentitions displaying
tooth wear include concerns relating to:
• Aesthetic impairment (fractured, unattractive
teeth/restorations or tooth discoloration)
• Difficulties with function, such as the efficiency of
mastication or lip/cheek or tongue biting
• Less commonly, comfort (pain and sensitivity)
Dahl B, Carlsson G, Ekfledt A. Occlusal wear of teeth and restorative materials.
Acta Odontol Scand 1993; 51: 299–311
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

MEDICAL HISTORY
may reveal underlying conditions which preclude
the provision of complex treatment plans, and may
also provide a valuable insight into the aetiology of
the wear pattern observed to be present
1. Medication
 asthma inhalers containing steroid or effervescent medication
 aspirin (salicylic acid)
 chewable vitamin C preparations (ascorbic acid)
 various iron preparations
 diuretic agents and antidepressant drugs
2. Presence of a gastro-oesophageal reflux as seen in
patients diagnosed with :
anorexia nervosa, bulimia nervosa or those with hiatus hernia,
sphincter incompetence, oesophagitis, or increased gastric
pressure (and volume)
Br Dent J 1984; 157: 16-19
Quintessence Int 1997; 28: 305–313
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

3. Female patients are affected by eating disorders
more frequently than males at a ratio of 10:1.5
Cyclical vomiting syndrome and voluntary regurgitation
(rumination) have also been reported as aetiological conditions
respectively
4. Pregnancy
 inc. in abdominal pressure
 Morning sickness
5. A history of heartburn or reflux is a key factor to note
Dent Update 2000; 27: 175–183
Quintessence Int 1996; 27: 123–127
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

PAST DENTAL HISTORY
will provide useful information as to the patient’s
previous level and experience of dental care
1. Oral hygiene habits should be ascertained, such as :
 type of toothbrush used,
 the intensity, the frequency and timing of toothbrushing as well as
the abrasivity of the dentifrice being used.
2. A poorly motivated patient or one with negative views
towards dental care or indeed a phobic patient may not be the
best candidate at first instance when considering complex
treatment provision
3. Establish (where relevant) any previous experience of
removable appliance/prosthesis wear experience
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

SOCIAL HISTORY
 lifestyle stresses
 occupational details which may also have a bearing on
their ability to attend for treatment plans which sometimes take
numerous visits to execute
 Swimmers
Copper mine workers
HABITS & DIETARY ANALYSIS
 Smoking, alcohol consumption or dietary trends
 A detailed dietary analysis
Of particular relevance to diet/beverages and tooth surface loss are the
copious consumption of citrus fruits, pickles, vinegar (acetic acid), coarse
food, cola, fruit juices and carbonated drinks
Br Dent J 1996; 180: 349–352
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The frequency and quantity of daily intake, the
duration of consumption and the method of
eating/drinking should be established
 The presence of other habits which may be aetiological by
nature such as that of pipe-smoking, pen/pencil biting, and
holding objects between teeth
 Patients affected by tooth wear should undertake a
three day consecutive comprehensive diet diary
(Watson and Burke)
Dent Update 2000; 27: 175–183
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

EXAMINATION OF THE WEAR’s
PATIENT
Clinical examination of the dentition has two
primary objectives:
1. To document and record the location, appearance
and degree of toothwear
2. To evaluate the progress of toothwear over time
Dent Update 2002; 29: 162–168
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

EXAMINATION OF WEAR’s PATIENT*
Extra-oral examination
Include a meticulous assessment of their
temporomandibular joints and associated musculature
 The presence of any joint or muscle tenderness, clicking, crepitation,
mandibular deviation on opening or closure or any associated aches/
pain
 The maximum jaw opening should be recorded (that less than 40
mm between incisal edges is considered to be restricted)
 Presence of parotid gland enlargement is often seen in bulimic
patients Quintessence Int 1996; 27: 123–127
*BDJ;2012 ; VOLUME 212 NO. 1
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 include an assessment of the freeway space (FWS),
by determining the patient’s resting vertical
dimension (RVD) and occlusal vertical dimension
(OVD), with the aid of callipers or by the use of a Willis
gauge
The facial vertical proportions should also be
carefully examined
 Other techniques that can be used for the evaluation of
vertical dimension include the use of phonetic assessments
(particularly the sibilant sounds), facial soft tissue contour
analysis, jaw tracking and the use of electrical muscle
stimulation techniques
 The smile line and lip line should also be noted, as well
as any midline discrepancies
Dent Clin North Am 1993; 36: 651–663
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

a typical appearance resulting from loss of
occlusal vertical dimension; note the presence of
an ‘inverted lip profile’

Relationship between lower lip line and incisal
edges of worn anterior teeth
Elongation of the
worn anterior teeth is
feasible
Elongation of the worn
teeth would lead to an
excessively long clinical
crown
(A) (B)
Dent Update 2002; 29: 162–168

Intra-oral Examination
 Presence of buccal keratoses, scalloping of the
tongue or signs of xerostomia
 The level of oral hygiene should be recorded together
with the undertaking of a Basic Periodontal Assessment
(BPE)
 A dental chart should be completed, detailing the
presence or absence of teeth, dental caries, restorations,
failed restorations, fractures, abrasions and erosive lesions
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 palatal erosion suggests an intrinsic aetiology
 labial erosion implicates extrinsic factors.
 Lesions involving incisal edges and cusps are generally
associated with attrition,
 Asymmetric lesions may be due to abrasion
 In addition to examining the teeth present, the absence of any
teeth should be noted, given that lack of posterior support can
predispose to anterior tooth wear
may provide additional clues to the underlying
cause.
For example,
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Once diagnosed, the location of tooth wear
(localised, anterior/posterior or generalised) and
severity of the tooth surface loss should be recorded
(as being restricted to enamel only, into dentine or
severely affecting the teeth or series of teeth)
Tooth Wear Index of Smith and Knight
 the presences (or absence) of:
• Crowding
• Rotations
• Tilting
• Drifting
• Spacing
• Over-eruption
• Mobility
A comprehensive occlusal assessment is mandatory.
The overbite and overjet
should also be measured
and recorded
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

The presence of a stable centric occlusion
(CO) should be determined, and tooth
contacts in the intercuspal position (ICP)
described
 The ease with which the patient can be manipulated
into their retruded arc of closure should also be
established
 Where a patient cannot be readily manipulated into centric relation
(CR), due to protective neuromuscular reflexes, the use of
deprogramming devices should be considered
1. use of cotton wool rolls and wood spatulas
2. anterior bite planes (Lucia jig)
3. full coverage stabilisation splints
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

DEPROGRAMMING
DEVICES
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Permissive splints as muscle
deprogrammers
 Are designed to unlock the occlusion to remove deviating tooth inclines from
contact
 When this is accomplished, the neuromuscular reflex that controls closure
into maximum intercuspation is lost
 The condyles are then allowed to return to their correct position in CR if
condition of the articular components permits
 Because all corrective tooth inclines are either separated or covered with
smooth plastic, permisive splints allow the muscles to function according to
their own coordinated interactions, thus eliminating the cause & the effects of
muscle incoordination
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
PETER E. DAWSON; Evaluation, diagnosis & treatment of
occlusal problems; 2ND EDITION

CENTRIC RELATION OCCLUSAL SPLINTS
Waxup showing contacts &
anterior guidance
Lateral view showing
posterior disclusion in
lateral excursions
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

CENTRIC RELATION OCCLUSAL SPLINTS
Adjusted splint-holding
contacts(black), lateral
canine guidance(red), &
protrusive(green)
Centric relation occlusal splints should be fabricated with
anterior guidance inclines that disclude posterior contact in
all eccentric jaw positions
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

HAWLEY BITE PLANE
(ANTERIOR BITE PLANE)
 Allows the occlusal vertical
dimension to be increased by
only a small amount without
exceeding the VDR
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
Martin D. Gross; Occlusion in Restorative
Dentistry; 1st edition

 The first point of tooth contact in CR, hence the
retruded contact point (RCP) should be identified
and the presence of any ‘slides’ (and the direction
of the latter) from CR to CO established.
 Tooth contacts during lateral excursive (canine guidance or
group function) and protrusive movements of the mandible
should be determined
 It is also important to note whether the slide from CR
to CO has a larger vertical or horizontal component
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 If present, any working side/non-working side
occlusal interferences should be described
 Where the patient may be partially dentate, an
evaluation of the denture bearing areas must be
undertaken, as well as the fit of any removable
prostheses
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
ESTHETICAL CONSIDERATIONS WHILE
EXAMINING THE PATIENT…….
EXTRA-ORAL INTRA-ORAL
 Facial Symmetry
 Facial-Dental Midline
 Comissural-Bipupillary
line
 Smileline
 Lower teeth-Lip
Symmetry
 Lower Lip Length
 Tooth Axis
 Balance of Gingival
Levels
 Zenith positioning
 Level of interdental
contact
 Relative Tooth
Dimension / Tooth Form
 Transitional lines
 Tooth Characterization

MIDLINE
ANALYSIS
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

BALANCE OF
GINGIVAL LEVELS
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

TOOTH DISPLAY
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

OCCLUSAL
CONSIDERATIONS
 OVERJET
 OVERBITE
 OCCLUSAL
PLANE
STRUCTURAL
COSIDERATIONS
 LACK OF TOOTH
STRUCTURE IN
WORN DENTITION
 PROBLEM OF
SPACE FOR
RESTORATIONS
BIOLOGICAL
CONSIDERATIONS
 PUPAL
INVOLEMENT
 NEED FOR POST &
CORE
 NEED FOR CROWN
LENGTHENING
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

OCCLUSAL PLANE
NORMAL STEP UP / STEP DOWN
(Alternate pattern)
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
LABIOLINGUAL INCLINATION
Draw a perpendicular
from the central to
occlusal plane

Radiographs
 Good quality, accurate long cone periapical
radiographs
 presence of any signs of alveolar bone loss
 Other factors, such as the root surface morphology, anatomy of the pulp
chambers of affected teeth, quality of pre-existing endodontic treatment(s),
presence of dental caries, widening/disturbance of the lamina dura, presence
of retained roots or any signs of periapical pathology (radiolucencies or radio-
opacities) should also be assessed.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Articulated study
casts
Good quality study casts poured in vacuum mixed die-
stone should be mounted on at least a semi-
adjustable articulator in centric relation
 Study casts will permit an assessment of the occlusion in the
absence of soft tissue/muscular interferences
The impact of tooth over-eruption can be more readily
assessed together.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The vertical and horizontal components of the slide from
CR to CO can also be examined at this stage
 Tooth contacts in CR, during lateral excursive
and protrusive movements, and the presence of
occlusal interferences can be more easily
determined
 The space gained by manipulating the mandible into CR
can be noted and the effect of ‘opening the bite’ on the
articulator on the residual dentition also seen, along with
the effect of any trial occlusal adjustments
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Sensibility tests
 Loss of vitality
important to establish the health status of the
dental pulp prior to embarking upon any
complex prosthodontic rehabilitation
 application of ethyl chloride,
 warmed gutta percha or
 electric stimuli to the tooth
However, the ‘true’ vitality status of a tooth can strictly be
only established with the use of Doppler flow techniques
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Intra-oral photographs
 Including anterior, posterior (left/right) views and
occlusal views of both arches are very important
 Images should be appropriately stored.
Salivary analysis
 can be undertaken for both stimulated and un-stimulated
secretion rates and respective buffering capacities.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Diagnostic wax mock-ups
may be fabricated with the desired final
occlusal scheme and aesthetic requirements
as prescribed by the operator
 They form a useful visual aid and communication tool, to assist in the
evaluation of aesthetics, tooth shape, length, and inclination
 wax up once duplicated by the means of a stone model can be used to
fabricate a vacuum formed PVC matrix that can initially be used to
demonstrate the proposed changes intra-orally by the application of a
provisional crown and bridge material into the vacuum formed matrix
 The matrix helps fabricate definitive restorations using direct resin
composite
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 wax mock-up can used as an aid to
help form tooth reduction guides,
assist with the fabrication of
provisional restorations, or used to
form a polyvinylsiloxane (PVS) index,
which helps form direct resin
composite restorations
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

A) Study casts of a patient displaying
tooth wear, mounted in centric
relation on a semi-adjustable
articulator
B) Diagnostic wax up fabricated in
accordance with an accurate occlusal-
aesthetic prescription
C & D) Information derived from the wax up has been used to guide the
placement of restorative materials

The diagnosis of a patient presenting with
tooth wear should include a description of
the type(s) of lesions observed, together
with an account of their extent/location
and severity.
DIAGNOSIS OF TOOTH WEAR
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Diagnose the lesion!!
ATTRITIONABRASION
ABFRACTION EROSION
HISTORY
Chief Complaint
Medical history
Habits
Occupation
Lifestyle
EXAMINATION
Extra-oral
Clinical
presentation
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

SEVERITY OF TOOTH WEAR
 Tooth Wear Index by Smith & Knight
 BEWE (Basic Erosive Wear Examination)
 THE ACE Classification
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

LOCATION OF TOOTH SURFACE LOSS
Finally, the pattern of tooth surface loss seen
should be sub-classified into being either
localised or generalised tooth wear
 In the case of localised tooth wear, it is important to
specify the region affected, such as anterior, posterior,
mandibular or maxillary
 Mandibular anterior teeth are relatively less affected by
the process of erosion than the maxillary anterior dentition.
 Posterior teeth are protected by secretions from the
parotid glands
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 For cases of localised wear, it is also worth
considering whether there may be space
available for the placement of restorative
materials
 For cases of generalised tooth wear, it is important to
categorise the amount of dento-alveolar compensation
that might have taken place
 The loss of tooth structure may or may not result in an
increase in the Freeway space (FWS)
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Following an evaluation of the existing vertical
dimension of occlusion (OVD) patients
presenting with generalised wear may be
assigned to three categories according to
Turner and Missirlian
Category 1
Category 2
Category 3
excessive wear with loss of vertical dimension of
occlusion
excessive wear without loss of vertical
dimension of occlusion, but with space available
excessive wear without loss of vertical
dimension, but with limited space
J Prosthet Dent 1984; 52: 467–474
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Dent Update 2002; 29: 162–168

Measurement of Severity & Progression
of Tooth Wear
 Tooth Wear Index by SMITH & KNIGHT
 PROFILOMETRY
 Diagnostic Casts / Study Models
 Silicone Impressions
 CONTACT STYLUS TECHNIQUE
 “FITTING” the Computer Models together
 OPTICAL TECHNIQUES ( LASER & WHITE LIGHT)
 MICROCOMPUTER TOMOGRAPHY SCANNING
METHOD
J Oral Rehabill. 2012 ;39; 217–225
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Silicone Impressions Technique:
A silicone putty
impression is taken in an
sectional tray
The putty (e.g. Rapid) is
removed from the tray
It is sliced into sections
with a scalpel
When a section is placed over the
tooth, it is a perfect fit. If wear
progresses, a gap will become
visible at future visits

 Xhonga et al. (1972) used profile tracings from
sectioned study models to estimate an avg. daily
rate of erosion in cervical lesions
 The real problem of measurement of tooth wear by
profilometry is that volumetric loss of tissue has a complex
shape which defies assessment by simple geometric
calibration, such as a ruler might give
Answer to the problem ofcourse lies in the capture of
entire anatomical tooth surfaces of the before and after time
interval
 This requires a digital technique with software facilities
for computer image rendering, fitting & measurement
Toothwear: ABC of the worn dentition; 1st ed
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

CONTACT STYLUS TECHNIQUE :
 Null point stylus
fixed in space & the
model of the tooth
which moves
underneath the stylus
 Digital scanning
rendered to the
computer , giving the
appearance of tooth
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

“FITTING” the Computer Models
together :
Wear on the incisal
edge of a canine
 The gray scaling
shows the anatomical
detail before (B), &
wear is superimposed
as a color reference 2
yrs after baseline (2y)
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

OPTICAL TECHNIQUES ( LASER & WHITE LIGHT) :
White light digital
profiler
(A) Light being emitted from one port
& detected by a CCD in the other
(B) 3 point triangulation
necessary to determine the
anatomical location of the
wear area

MICROCOMPUTER TOMOGRAPHY SCANNING:
Micro-Computer Tomography derived model of long term cervical
abrasive wear
Note the inclusion of undercut in the total profile of lesion
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

REPORTING
TOOTHWEAR
 VOLUME REPORTING
DEPTH LOSS
INCREASE IN AREA OF CONTACT
DEPTH × AREA = VOLUME
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

OBJECTIVES of Tooth Wear Measurement by
Profilometry :
Is Occlusal Attrition or Erosion the more rapid
process?
Does the rate of Erosion differ in different molars?
Does the rate of Erosion differ on different
cusps on the same tooth?
Is the rate of erosion affected by preventive therapy?
Is the rate of attrition affected by splint therapy?
Does the rate of cervical tisssue loss relate to occlusal
loss?
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Problems with these latest gadgets!!!!
× despite improved accuracy and reliability,
new sophisticated measuring tools are costly
and require specialised hardware and
software, restricting their use in everyday
dental practice
Al-Omiri et al. compared the reliability of three different methods
to detect incisal wear over a 6-month period.
The methods used were a CAD–CAM laser scanning machine, a
tool maker microscope for micromeasurement applications and a
conventional toothwear index (Smith and Knight wear index).
It was found that the tooth wear index was the least sensitive for
tooth wear quantification and was unable to identify wear
progression in most cases
J Dent. 2010;38:560–568
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Problems with these latest gadgets!!!!
× However, the fundamental problem with in
vivo wear studies is the inherent patient
factor
× In addition, the sensitivity of measurement
and replica techniques are an important consideration
 Therefore, appropriate training and calibration are
important to minimise subjective errors and a combination of
methods should be used for a more reliable quantitative
analysis
J Oral Rehabil. 2001;28:1048–1055
J. Engineering Tribology. 2005;219:2–19
J Oral Rehabill. 2012 ;39; 217–225
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

DILEMA OF OCCLUSION
The three-dimensional relationship of the
mandible to the maxilla, and the clinician's
understanding of it, is fundamental in clinical
dental practice
No matter the degree of restorative dental treatment
provided, be it a small occlusal restoration to a full-
mouth rehabilitation, the occlusion is affected to a
greater or lesser extent
British Dental Journal 2004; 196: 395–40
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Occlusion has been defined simply by
Davis and Gray as ‘the contacts
between teeth'
 These contacts can be considered statically or dynamically,
as teeth slide over each other during mandibular movement
 In addition to the occlusion, the masticatory system is also
composed of the periodontal ligaments, TMJ , the muscles of
mastication and their associated ligaments
 The system is under the control of higher centres in the
central nervous system
Br Dent J; 2001; 191: 235-245
Br Dent J 2001; 191: 291-302
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Various School of Thoughts for mandibular
positions
 The early Conical and Spherical theories were
superseded by the mechanical models of the
Gnathologists
 These theories were largely driven by developments in
articulator design
 In recent years, the engineering model of occlusion has been
tempered by an increased appreciation of the biological aspects
of the masticatory system.
degree of adaptability
J Prosthodont 1993; 2: 33-43
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The occlusion achieved during normal
functional mandibular movements, such as
swallowing and chewing, occurs within a relatively
small space called the “envelope of motion”
 Abnormal movements are dysfunctional, caused by
derangement of the articular disc and muscle
hypertrophy
 Parafunctional activity is usually habitual, the patient
often being unaware of the movement, and includes
bruxism, clenching, jaw posturing, lip and pencil biting
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

These activities can create excessive forces
between teeth or produce normal forces at an
abnormal frequency, producing a risk of:
 fractured cusps or restorations;
 increased tooth mobility;
 muscle fatigue; and
 toothwear
“A harmoniously functioning occlusion allows for smooth
uninterrupted movements over the area of tooth contact”
 Some occlusions may not permit such free movements,
yet the patient does not exhibit the problems described;
his/her neuromuscular system has adapted to the
disharmony
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 However, if a restoration is placed which
changes the occlusion, the adaptive capacity of
the system may be exceeded, leading to the signs
and symptoms
“ Therefore restorations should be planned so that
they do not cause effects that exceed the adaptive
Tolerance ”
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 They represent the movement of the tip of the lower
incisor when viewed in the sagittal or frontal plane
Posselt described the extreme or border
movements of the mandible as an
“envelope of motion“
Dent Update 2003; 30: 150-157
J Prosthet Dent 1957; 7: 787–797
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Acta Odontol Scand 1952; 10: Suppl 10

 The mandible initially opens with a hinge
movement about a horizontal axis known as the
retruded axis or terminal hinge axis (THA), with the
condyles in the retruded position (RP) (centric
relation)
 This is described as the most superior position of
the condyles in their fossae
 When the mandible rotates around
this axis the first tooth contact occurs
– the retruded contact position (RCP)
 The mandible then slides forwards
bringing the teeth into maximum
intercuspation – the intercuspal position
(ICP) (centric occlusion)
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

The discrepancy between RCP and ICP has both a
vertical and horizontal component and may be up
to 1 mm.
However, patients with this slide usually close straight into
ICP from the rest position – the habitual path of closure
Acta Odontol Scand 1952; Suppl 10
 Contact between opposing teeth can occur in the area of
this discrepancy during swallowing, mastication and
parafunctional activity.
 When teeth are in the intercuspal position the occlusal
vertical dimension (OVD) is defined as a measurement of face
height
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 When not in contact, teeth are held apart in
the rest position by the muscles of mastication
acting on the mandible creating a freeway space
or Interocclusal distance of 2–4 mm
 In practice, this position is variable, being affected by posture
and muscle activity
 When mandibular teeth move from ICP to maximum
protrusion their path is determined by the articulating
surfaces of the anterior teeth, creating anterior guidance
 This does not exist in anterior open bites or edge-to-edge
incisor relationships, where during protrusion the guidance
is obtained from the occlusal surfaces of the posterior teeth
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

The angle and length of the movement is
determined by the incisor relationship
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

ICP is maintained and occlusal forces directed
axially by two types of Interocclusal contact:
 The maxillary buccal and mandibular lingual cusps are
therefore the non supporting cusps.
 The palatal cusps of the maxillary teeth and buccal cusps
of the mandibular teeth (called supporting cusps) contact
the inclined planes of the opposing dentition or the cusp
tips contact the opposing fossae
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 During lateral excursions, the side to which the
mandible moves is the working side and the
opposite side the non-working side
 On the working side, when only the canines are in contact
during lateral excursions, the occlusion is canine guided; if two
or more pairs of teeth contact in this movement the occlusion is
in group function. This may involve both anterior and posterior
teeth
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 On opening from RCP the mandible rotates
around the THA in an arc of a circle (point Y)
 This creates an incisal separation of about 2.5 cm.
 On further opening the condyles translate or slide
downwards and forwards along the articular eminencies of
the glenoid fossae to a point of maximum opening
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 During lateral movements, the working side or
rotating condyle may rotate and move laterally as
well as upwards, downwards or backwards. The
lateral component is termed the Bennett
movement
 The first part is called
immediate sideshift and is
measured on average at 0.5 mm.
The progressive sideshift
describes a more gradual
lateral movement
 The non-working side or
biting condyle moves
downwards, forwards and
inwards, creating the Bennett
angle
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 The free-sliding movement of the mandible can
be disturbed by an occlusal interference occurring
between opposing teeth
 The interference may arise as a result of tooth movement,
over-eruption or occlusal wear in the unrestored dentition or
of poorly contoured restorations
 To maintain occlusal stability there must be adequate
occlusal contact to prevent such interferences
 This stability can be maintained by assuring occlusal
contacts are not on inclined planes but ideally in a cusp-to-
fossa or cusp to marginal ridge position
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

ASSESSMENT OF THE OCCLUSION
The diagnostic process begins with careful
history taking and clinical examination
The examination should include:
 Extra-oral components – temporomandibular joints,
muscle hypertrophy/spasm
 Mandibular movement – painful, deviated, abnormal
or restricted
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

ASSESSMENT OF THE OCCLUSION
Intra-oral features:
1. Intercuspal position, retruded contact position, lateral &
anterior guidance.
2. Presence, angle & smoothness of any slide from RCP to ICP.
3. Location and extent of occlusal faceting.
4. Ease of movement between mandibular positions as in 1.
5. Extent of posterior support.
6. Over-erupted, tilted or mobile teeth
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

DETECTING OCCLUSAL CONTACTS
 Articulating paper is used to mark or indicate
the position of occlusal contacts. Thin articulating
paper such as GHM occlusion foil which is 19 microns
thick, marks true contact points; thicker paper (70–200
microns) can produce inaccurate and often larger
points
 To show occlusal contacts the teeth must be dry
 Articulating paper, held in Miller’s forceps , is placed
between the teeth and the mandible guided into whichever
position is being assessed to record the points of tooth
contact
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Articulating paper
held in Miller’s
forceps
Different occlusal
indicators – wax, paper,
shimstock
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

T-SCAN III SYSTEM
(Computerised occlusal analysis Technology)
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Contacts with
articulating
paper
Occlusal analysis with T-scan III
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Articulated study casts, mounted on a semi-
adjustable articulator using a facebow record,
provide more detailed information that cannot be
readily assessed in the mouth
 The casts must be articulated in RP so any slide from this
position to ICP is detectable
 The interocclusal records must also include lateral
excursions and protrusion so both the horizontal and vertical
condylar guidance and incisal guidance can be programmed
into the articulator
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Retruded Contact Position
“Guided occlusal relationship occurring at
the most retruded postion of the condyles
in the joint cavities”
 A position that may be more retruded than the
centric relation position
The Academy of Prosthodontics
Glossary of prosthodontic terms
J Prosthet Dent 1999; 81: 48-106
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

“The maxillomandibular relationship in which
the condyles articulate with the thinnest
avascular portion of their respective discs,
with the complex in the anterior-superior
position against the slopes of the articular
eminences”
 This position is independent of tooth contact.
 It is restricted to a purely rotary movement about the
transverse horizontal axis
CENTRIC RELATION
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Intercuspal position
“The complete intercuspation of the opposing
teeth independent of condylar position.”
 Sometimes referred to as the best fit of the teeth regardless
of the condylar position
Centric occlusion
“The occlusion of opposing teeth when the mandible
is in centric relation”
 This may or may not coincide with the intercuspal
position
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

IMPORTANCE OF RCP
RCP is said to be a “relatively reproducible
position” and as such is useful in the restorative
management of dentate and edentulous individuals
and as a reference point for the registration of
transfer records, so that casts can be mounted
on articulators
 Posselt in his classic treatise ‘Studies in the Mobility of the
Human Mandible', found that the retruded position of the
mandible was reproducible to within 0.08 mm and thus
could be termed a border movement
Acta Odontol Scand 1952; 10: Suppl 10.
J Prosthet Dent 1964; 14:,266-278
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

In Dentate subjects….
 RCP is an unstrained
position of the mandible
relative to the maxilla
occurring at initial tooth
contact
 This contact follows closure about the terminal hinge axis
where the condylar heads are in their most anterior and
superior position in the glenoid fossae
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Relevant bony anatomy of the skull base
and the right TMJ articulation
A: mastoid process
B: right glenoid (articular)
fossa with the antero-
superior aspect shaded,
C: zygomatic arch
D: posterior hard palate,
E: pterygoid plates, and
F: styloid process
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Posselt in 1952 found that in 10% of dentate
individuals, the RCP coincided with the intercuspal
position.
 For the remainder, the RCP is infero-posterior to ICP by
0.5—2 mm
 The movement from the RCP to
the ICP is known as a “slide”
 A slide has the potential for a
combination of horizontal, vertical
and lateral components along its
path
Acta Odontol Scand 1952; 10: Suppl 10.
Dent Update 1991; 18: 141-145.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Subjects with an easily identifiable, stable and
comfortable ICP may only require a conformative
approach rather than reorganisation at RCP.
 Reorganisation involves altering a patient's existing
ICP to a new ICP.
 This new ICP is made coincident with RCP because
of the reproducibility of the latter.
 This will eliminate the RCP-ICP slide
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

In Edentulous subjects…
 There are no natural tooth contacts to define a
retruded contact
 In this situation, prosthetic tooth
contact (or wax occlusal rim contact) will
be along the retruded arc of closure at
some point
 This is dictated by the occlusal
vertical dimension (OVD) appropriate for
that patient. Therefore, the mandible and
maxilla are in CR at this occlusal vertical
dimension and it is from here that the
prosthetic occlusal scheme is constructed
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

USES OF RCP IN THE DENTATE PATIENT
 Mounting models on an articulator.
Mandibular movement can be simulated
because of pure rotation about the
terminal hinge axis
Helkimo M. Prosthodontic treatment of partially edentulous patients. Various centric
positions and methods of recording them. Zarb G A, Bergman B, Clayton J A, MacKay H F
(eds) pp171-187. St Louis: CV Mosby, 1978
 Reorganising a patient's occlusion at a new occlusal
vertical dimension
 Occlusal analysis in cases of toothwear, tooth
mobility, drifting, pain or repeatedly failing
restorations.
Br Dent J 2001; 191: 291-302
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Occlusal splint therapy
J Prosthet Dent 2001; 86: 539-545
 ‘Distalising' the mandible to create palatal
space for anterior restorations
J Oral Rehab 2000; 27: 1013-1023
 Restoring a tooth which is involved in
determining the RCP
Br Dent J ;1982; 152: 160-165
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Midline analysis in cases of facial asymmetry,
in order to separate dental and skeletal causes
 Determining the magnitude and direction
of the RCP to ICP slide in order to assess
the resultant force applied to anterior
restorations
J Oral Rehab;2001; 28: 55-63
Ramfjord S P, Ash M M. Occlusion. 4rd edition, p 305.
Philadelphia: WB Saunders Co, 1995
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 It has been suggested that RCP is attainable
during mastication and deglutition, and that
restoring a patient to this position may result in
enhanced masticatory efficiency and occlusal
stability
J Oral Rehab 2000; 27: 1013-1023
Ramfjord S P, Ash M M. Occlusion. 4rd edition, p 305.
Philadelphia: WB Saunders Co, 1995
 Furthermore, it has been demonstrated that the
reorganisation of patients to a situation where RCP
coincides with ICP will relapse after a period of time so that
a slide between the two is re-introduced
Prosthet Dent 1973; 30: 591-598
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

FACTORS AFFECTING THE RCP RECORDING
 Recording RCP is dependent upon a number of
factors including the patient, operator experience and
training ,the registration material and recording
method employed, the time of the recording, guidance
of the mandible, neuromuscular conditioning and
record handling and storage
 The diurnal variance of recording maxillomandibular
relationships has been studied in 13 subjects by Shafagh et al
 Shafagh et al. found that retruded mandibular recordings made
in the evening were more posterosuperior than those made in the
morning
J Prosthet Dent 1975; 34: 574-576
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 In the dentate individual the RCP record is taken
at a slightly increased OVD just prior to tooth
contact (CR) with the mandible rotating about the
terminal hinge axis
 If tooth contact occurs, involuntary programmed
mandibular deviation from the hinge axis will result due to
sensory feedback from periodontal ligament
mechanoreceptors
 Neuromuscular conditioning and the abolition of reflex patterns
of closure can be achieved by the patient biting the teeth together
hard, biting on cotton rolls, holding the mouth open wide, use of
an anterior jig or use of an occlusal splint
Br Dent J 2001; 191: 291-302
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 Other influences that affect the RCP recording
include general health, attitude to treatment, co-
operation and comprehension of the procedure, the
patient's body, head and tongue position, state of
relaxation, medication and state of anaesthesia
 The number of teeth, their condition or the ridge form of
edentulous patients will effect the stability of the recording
medium and thus the quality of the recording
 Pain from the operator's guidance technique, the
temporomandibular joints or from muscle tension will
result in reflex mandibular protrusion and hence erroneous
recordings
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

MANDIBULAR GUIDANCE & RCP
The aim of mandibular guidance is “to help locate
the condylar heads in the glenoid fossae at the
terminal hinge axis in a consistent manner, thus
producing mandibular closure about the terminal
hinge axis”
Can be divided into those which are
PATIENT-GUIDED
 Schuyler technique
 Physiological technique
 Gothic arch (Arrow-point)
tracing
 Myo-monitor
OPERATOR-GUIDED
 Chin-point guidance method
 Three finger chin-point guidance
 Bimanual manipulation method
 Anterior guidance by a Lucia Jig,
Leaf Gauge , tongue blade ,
OSU Woelfel Gauge
 Power-centric registration method
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Schuyler technique
J Am Dent Assoc 1932; 19: 1012-1021
Physiological technique
 uses cones of soft wax
placed posteriorly.
 IN EDENTULOUS
patientsJ Prosthet Dent 1955; 5: 319-322
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
PATIENT-GUIDED…

Gothic arch (Arrow-point) tracing
Maxillary and
mandibular occlusal
rims with a metal plate
on the upper (left) and
stylus on the lower
(right)
Dent Cosmos 1910; 52: 1-19
Br Dent J 1994; 176: 386-393
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Where the lines meet on the plate represents the
retruded mandibular position
The stylus scribes an
arrow-head shaped
tracing on the maxillary
plate outlining the
protrusive and right and
left lateral excursions of
the mandible
Br Dent J 1994; 176: 386-393
Dent Cosmos 1910; 52: 1-19
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 A system of recording a gothic
arch tracing extra-orally
 The stylus plate system is
attached to the rims via forks
Br Dent J 1994; 176: 386-393
Dent Cosmos 1910; 52: 1-19
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Myo-monitor
 an electrical jaw muscle stimulating device
which is reputed to achieve muscle
relaxation and produce a neuromuscular
mandibular position
 Eg. J-4 Muscle Stimulator which produces pulsed ultra-low
frequency stimulation of facial and masticatory muscles
 Stimulating electrodes are placed over the coronoid notches
& a common electrode is located at the nape of the neck
 Proponents of the myo-monitor suggest that the
‘jaw-closer' muscles act simultaneously, via reflex contraction,
to produce a reproducible retruded mandibular position
Quintessence Int 1972; 12: 57-62
Prosthet Dent 1975; 34: 245-253

Chin-point guidance method
Patient's mandible
is guided into a
hinge closure by
the thumb and
index finger of the
operator
Prosthet Dent 1960; 10: 849-855
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION
OPERATOR-GUIDED…

Three finger chin-point guidance method
A tripod is created at the
chin-point and lower
border of the mandible
on both sides by the
thumb, index and third
finger
 not recommended for
edentulous subjects
Int J Perio Rest Dent 1984; 4: 62-66
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Bimanual manipulation method
Technique is carried out
with the patient supine
and the operator seated
directly behind.
 fifth finger of each hand is placed behind the angle of the
mandible, with the fourth fingers positioned just in front of
the angle
Prosthet Dent 1973; 29: 100-104
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Bimanual manipulation method
 Third fingers are
placed on the inferior
surface of the body of
the mandible, and the
index fingers submentally
in the midline
 Thumbs are positioned laterally to the symphysis
 An alternative method, with the operator in front of the
patient, is to use the index fingers to stabilise the lower
record base and guidance is from the thumbs on the chin
Prosthet Dent 1973; 29: 100-104
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Anterior guidance by a Lucia Jig
The basis of the Lucia jig method and the techniques that
follow, is to provide an anterior reference point
J Pros Dent 1964; 14: 492-505.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 An anterior stop also stabilises the mandible
during recording and permits minimal tooth
separation so that the recording medium is as thin as
possible
 The lingual aspect should slope posteriorly and superiorly
at an angle of between 40–60°
 A selected lower incisor scribes an arrow-head pattern, the
‘wings' and ‘tail' of which can be ground away to leave the apex
J Pros Dent 1964; 14: 492-505.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

 This process is repeated until a raised area
of acrylic at the apex remains
 This is the location of the retruded position and the
vertical height is then adjusted until the posterior teeth are
just out of contact
 The record is made at this position with the jig in the mouth
It is important to note that while the jig is being adjusted out
of the mouth, the patient must bite on a cotton wool roll or a
saliva ejector
J Pros Dent 1964; 14: 492-505.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Anterior guidance by a tongue blade
 The degree of tooth separation
can be altered by the number of
spatulas used
 The patient's teeth must be
discluded for a period of time,
usually between 10–20 minutes
prior to registration
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Anterior guidance by a Leaf Gauge
J Prosthet Dent 1973; 29: 608-610.
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Anterior guidance by a OSU Woelfel Gauge
 was developed by Woelfel at Ohio State University (OSU)
 The specially designed device has a graduated acetate bite
platform, the position of which is adjusted antero-posteriorly
until the teeth are minimally out of contact
J Prosthet Dent 1986; 56: 716-727
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Power-centric registration method
 Operator employs a directed force to achieve
a retruded mandibular position
 With the dentist standing in front and to the right of the
supine patient, the left thumb and forefinger are placed over
the upper teeth
 right thumb is placed on the superior aspect of the chin,
while the second and third fingers take up position along the
inferior border of the mandible
Clin Orth 1981; 15: 32-46
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Power-centric registration method
 Operator's right arm is stiffened and pressure is
applied from the shoulder by leaning
 It has been suggested that reflex muscle shortening acts
to retrude the mandible
Clin Orth 1981; 15: 32-46
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Wise described RCP location techniques for the
dentate patient based upon the relative ease of
mandibular manipulation
‘EASY' bimanual manipulation
‘manipulation with slight difficulty'
Anterior guidance from a tongue blade
followed by bimanual manipulation
‘manipulation with more difficulty'
Lucia jig which may need to be left in situ for up to
30 minutes
Br Dent J 1982; 152: 160-165
 For some very difficult patients, an occlusal splint for an
extended period
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

Discrepancy Between RCP and ICP
 The mandible is manipulated into RCP and the
patient instructed to slide his or her teeth together
until they meet in ICP or in the position that feels
correct to them
 This is identified using articulating paper
 Lateral excursions are then made to detect the nature of
the guidance and finally protrusive movement is used to
demonstrate the type of anterior guidance
Dent Update 2003; 30: 150-157
HISTORY
EXAMINATION
DIAGNOSIS
ANALYSIS
OCCLUSION

2.diagnosis restoration of worn dentition

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