2. CONTENTS
• INTRODUCTION
• DEFFINITIONS
• OBJECTIVES OF FMR
• INDICATIONS OF FMR
• REASONS FOR FMR
• LIMITATIONS OF FMR
• MASTICATORY SYSTEM DISORDER
• DIAGNOSTIC WAX UP
• EXAMINATION, DIAGNOSIS AND
TREATMENT PLANNING IN FMR
• VERTICAL DIMENSION
• CENTRIC RELATION
• LONG CENTRIC
• OCCLUSAL
EQUILIBERATION/PRINCIPLES OF
OCCLUSAL CORRECETION
• TREATMENT PROCEDURES AND
TECHNIQUES IN FMR
• FINAL RESTORATIONS FOR FMR
• COMMON PROBLEMS AND
DIFFICULTIES IN FMR
• POST OP CARE
• TECH FUTURE IN FMR
• CONCLUSION
• REFERENCES
2
3. Ultimate goal -
Optimum oral
health
Introduction
• The term ‘full mouth rehabilitation’ is used to indicate extensive and
intensive restorative procedures in which the occlusal plane is modified in
many aspects in order to accomplish “equilibration”.
Multidisciplinary
Approach
Both function and health can be
restored in badly detiorated, diseased
mouths by utilizing modern
techniques of oral rehabilitation
3
4. Definition (GPT9)
• Full mouth rehabilitation is defined as the restoration of the
form and function of the masticatory apparatus to as nearly a
normal condition as possible
The word rehabilitate implies ‘ To restore to good condition or to restore to former privilege’.
Reynolds JM. Modern gnathological concepts—Updated: By Victor O. Lucia, DDS, FACD Chicago, 1983, Quintessence
Publishing Co., Inc. 439 pages, illustrated, indexed.
All the procedures necessary to produce healthy, esthetic, well
functioning, and self-maintaining masticatory mechanism.
4
5. Objectives of FMR
• A static centric occlusion in harmony with centric
relation.
• Even distribution of stresses in centric occlusion and on
eccentric functional inclines.
• Equalization of forces directed against supporting
structures
• Restoration of normal healthy function of the
masticating apparatus
Irving Goldman: The goal of full mouth rehabilitation, J PROSTHET DENT 1951, vol 2, 246-251
5
6. Reasons for full mouth rehabilitation
• Obtain and maintain the health of periodontal tissues.
• Temperomandibular joint disturbance
• Need for extensive dentistry as in case of missing teeth, worn
down teeth and old fillings that need replacement.
• Esthetics as in case of multiple anterior worn down teeth and
missing teeth.
Reynolds JM. Modern gnathological concepts—Updated: By Victor O. Lucia, DDS, FACD Chicago, 1983, Quintessence
Publishing Co., Inc. 439 pages, illustrated, indexed.
6
7. INDICATIONS
• Restore impaired occlusal
function
• Preserve longevity of remaining
teeth
• Maintain healthy periodontium
• Improve objectionable esthetics
• pain and discomfort of teeth
and surrounding structures
CONTRAINDICATIONS
• Malfunctioning mouths that do not need
extensive dentistry and have no joint
symptoms should be best left alone.
• Prescribing a full mouth rehabilitation
should not be taken as a preventive
measure unless there is a definite evidence
of tissue breakdown.
• No pathology- No treatment.
Reynolds JM. Modern gnathological concepts—Updated: By Victor O. Lucia, DDS, FACD Chicago, 1983, Quintessence
Publishing Co., Inc. 439 pages, illustrated, indexed.
7
8. Classification of patients requiring
occlusal rehabilitation
Classification by Turner and Missirlain (1984)
The patients were classified into three categories –
• Category 1 - Excessive wear with loss of vertical dimension.
• Category 2 - Excessive wear without loss of vertical dimension
of occlusion but with space available.
• Category 3 - Excessive wear without loss of vertical dimension
of occlusion but with limited space available
Turner KA, Missirlian DM. Restoration of the extremely worn dentition. Journal of Prosthetic Dentistry. 1984 Oct 1;52(4):467-74.
8
9. Restoring vertical dimension at occlusion
• loss of occlusal vertical dimension
due to unstable posterior occlusion or
congenital disease and exhibit
excessive wear of anterior teeth.
• method to confirm loss of vertical
dimension is with trial restorations
• A removable occlusal overlay splint or
a treatment partial denture that
restores the occlusal vertical dimension
is given for 6-8 weeks and the patient
is evaluated for comfort and function.
• teeth are prepared and provisional
fixed restoration are given 2-3 months.
• Then the final restorations can be
given
Category 1
J PROSTHET DENT 1984, vol 52, 467-474
9
10. • A long history of gradual tooth wear caused by bruxism or moderate oral habits
• Anterior slide is present from centric relation to centric occlusion.
• Equilibration or stability of posterior teeth for stability in centric relation, in
combination with enameloplasty of opposing teeth can provide sufficient space
for restorative materials.
• gingivoplasty and gingivectomy , 2-3mm of supporting bone can usually be
removed without jeopardizing periodontal support, dynamic recordings of
mandibular movement ,are recommended for this type of rehabilitation.
Category 2
10
11. •
• exhibit minimum posterior wear but excessive gradual wear of anterior teeth
over many years.
• Centric relation and centric occlusion are coincidental.
• Restoring this patient is most difficult because vertical space must be obtained
for restorative materials
• Increasing the occlusal vertical dimension to achieve space for restorative
materials where there has apparently been no loss of occlusal vertical
dimension is seldom advisable; but if deemed necessary , the increase should be
minimal and for restorative needs only.
• Trial restorations are crucial and must be evaluated for longer period of time
to ensure patient accommodation to the altered occlusal vertical dimension
Category 3
11
12. Classification by Brecker
• Group I
Class I – Patients with collapse of vertical dimension of occlusion because of shifting
of existing teeth caused by failure to replace missing teeth.
Class II – Patients with collapse of vertical dimension of occlusion because of loss
of all posterior teeth in one or both jaws with remaining teeth in unsatisfactory
occlusal relationship.
Class III – Patients with collapse of vertical dimension of occlusion because of
excessive attritional wear of occlusal surfaces.
Brecker SC. Clinical procedures in occlusal rehabilitation. WB Saunders; 1966.
12
13. Group II
• Class I – Patients with all or sufficient natural teeth present, with satisfactory
occlusal relationship.
• Class II – Patients with limited teeth present but in satisfactory occlusal relationship
requiring aid in the form of occlusal rims.
Group III – Patients requiring maxillofacial surgery or orthodontic treatment as an aid
in restoring the lost vertical dimension.
Group IV – Patients in whom sectional treatment is required over extended periods of
time because of status of health of the patient, age or economic factor.
Clinical procedures in occlusal rehabilitation .W.B Saunders,Philidelphia 1958
13
14. Etiology of extremely worn dentition
Congenital abnormalities Amelogenesis imperfecta
Dentinogenesis imperfecta
Parafunctional occlusal habit Chronic bruxism and other habits
Abrasion
Erosion
Loss of posterior support
Bernard smith :Tooth wear : Etiology and diagnosis Gerodontology Text Book 1994, 88-102 46/400
14
15. Attrition Abrasion Erosion Splayed teeth Advanced occlusal
disease
Anterior
guidance
attrition
Sensitive teeth Sore teeth Hypermobility Spilt teeth and
fractured cusps
Painful
musculature
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 21-26
15
16. Diagnosis
Ist appointment
• Listen to patient’s opinion and
expectations
• Make diagnostic casts
• Radiographs
• Bite records and facebow transfer
IInd appointment
• Individual tooth is meticulously
examined
• Extracted or restored
• Serve as abutments for RPDs or
fixed prosthesis
Tentative treatment plan done
EXAMINATION DIAGNOSIS AND TREATMENT PLANNING IN FMR
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 360-363
16
17. Diagnostic aids
• Medical history
• Dental history
• Behaviour evaluation
• Radiographs – Complete mouth periapical radiographs and orthopentamograph
• Photographs – to remind previous state of mouth prior to restorative therapy
• Clinical examination
• Diagnostic wax-up
• Computer imaging
• CBCT
Bowley JF, Stockstill JW, Attanasio R. A preliminary diagnostic and treatment protocol. Dental Clinics of North America. 1992 Jul;36(3):551-68.
17
18. DIAGNOSTIC WAX UP
• The process of converting the programmed
treatment plan into a three dimensional
visualisation
• Before diagnostic wax-up, the occlusal
discrepancies in centric and eccentric occlusion
should be eliminated
• Thus planning of subgingival margins or surgical
crown lengthening required can be done
• Then wax is used to appropriately shape all
crowns and final prosthesis is planned
can be used to prepare an elastomeric
putty mould and used for temporization
or sectioned through long axis of tooth to
act as reduction guide intra-orally.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 365-366
18
19. Steps in the diagnostic wax up
• Step 1: Mount upper and lower casts with
centric relation bite record and facebow.
Duplicate the casts to preserve the original
conditions.
• Step 2: Verify the accuracy of the mounting.
• Step 3: Examine the occlusal relationship on
the casts.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 365-366
19
20. • Step 4: Lock the centric latch when
observing the casts.
• Step 5: Determine the correct vertical
dimension.
• Step 6: Return the condyles to centric
relation and lock the centric lock.
Occlusal interferences should be eliminated by selective grinding on the casts until the incisal pin contacts the
guide plate. At that point, the original vertical dimension will have been re-established in centric relation. If a
change in VDO is needed to fulfil requirements for stability, it can be determined now.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 368
20
Unlock the centric latch and close the teeth into maximum intercuspation.
This is the vertical dimension established by the elevator muscles.
Lower the incisal guide pin so it touches the guide table.
21. • Step 7: Observe the teeth that were reshaped.
• Step 8: Remove unsavable teeth from the
casts. From the clinical exam, all teeth that
cannot be saved are marked with an X.
• Step 9: Mark decisions that have been made
to use certain types of restorations.
• For example, in the figure the two upper
molars have been predetermined to need
crowns (C).
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 368,369
21
22. • Step 10 : Equilibration is the first treatment
option to explore.
The jaw-to-jaw relationship at the first point of tooth
contact in centric relation.
Equilibration of the casts clearly shows that reshaping
the teeth is a good choice of treatment because contact
with the canines is achievable by selective grinding away of
the deflective interferences.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 369
22
23. • Step 11: Examine the plane of occlusion.
• If the casts were mounted with a facebow
that was parallel with the eyes, the incisal
plane and the occlusal plane will relate to
the bench top.
• If the occlusal plane is slanted in the mouth
(yellow line), it will be slanted on the
articulator (red line)
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 370
23
24. • The occlusal plane established by the
simplified occlusal plane analyzer.
• Model is trimmed back to the
established new occlusal plane.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 370,371
24
25. Note how the buccal surfaces have been
contoured to move the cusp
tip more in line with the upper teeth. The
wax-up has been started.
The completed wax-up. These corrected casts are now used
to form a putty matrix for fabrication of provisional
restorations. They are also the perfect visual aid when
presenting the treatment plan to the patient.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 371
25
26. • Step 12: Establish stable holding contacts on
the anterior teeth.
• Step 13: Correct lower incisal edges if needed.
This refers to both position and contour.
Unmounted casts do not provide the
information needed to fulfill
this objective
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 371,372
26
27. • Step 14: Start with the lower anterior teeth.
• Step 15: Re-evaluate the total occlusion with
the upper cast to see it can be adapted to
occlude with the lower arch.
The range of change in
position of lower anterior
teeth is minimal compared
with the upper anterior
teeth.
Anteroposterior position
of lower anterior teeth has
very little flexibility, and
their position in the
narrow alveolar ridge is
quite limited.
The height of lower
incisors is also within a
limited range that is
consistent with the height
and contour of the
occlusal plane
simplifies the whole wax-up.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 371,372
27
28. Step 16: Establish holding contacts on the upper anterior teeth
This
diagnostic
wax-up
positioned
the incisal
edges
forward
and
also made
the teeth
longer.
Casts of a
patient with
a tight
neutral zone
that
positioned
the upper
anterior
teeth with a
lingual
inclination.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 374
28
29. A digital photograph of this patient shows
the incisal edges in line with the inner
vermillion border of the lower lip. It also
shows a lingual inclination of the upper
anterior teeth.
This photograph shows how the provisional
restorations made from the wax-up had to be
recontoured back to achieve a comfortable lip
closure path and phonetics.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 375
29
30. Cast of poorly contoured
anterior restorations. Note
the contour
of the pontics where they
meet the ridge.
Cast showing defect of lost labial plate of
bone that makes it impossible to establish
gingival contours on pontics that are
esthetically pleasing.
Fill-in of area with pink wax
will be used to communicate
desired result to the surgeon. A
bone augmentation was
needed to achieve the planned
contour. All guesswork was
eliminated.
Recontouring of the anterior teeth on the
cast will be used to
form provisional restorations, as well as
explain the treatment
goal to the patient and the surgeon.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31.page no. 376,377
30
31. Treatment plan
• Comprehensive treatment plan
must be established prior to start
of the treatment .
• Communication and patient
education are essential in order to
match the dentist’s and patient’s
definition of success
1) Pre-
prosthetic
phase
2) Prosthetic
phase
3) Maintenance
phase
31
Immediate
treatment
Definitive
treatment
32. Preprosthetic phase
• To develop proficiency in diagnosing the need of occlusal rehabilitation,
periodontist , orthodontist , endodontist , oral surgeon and prosthodontist must
all be integrated in establishing an environment conducive to oral health.
Orthodontic
considerations
Periodontal
considerations
Endodontic
considerations
Oral surgical
considerations
Minor
orthodontic
tooth
movement-
tooth can be
uprighted,
rotated,
moved
laterally,
intruded or
extruded to
improve axial
alignment,
create
favorable
pontic space
and direct
occlusal forces
along the long
axis of teeth.
Scaling and root surface curettage bring back the gingival health.
Surgical crown lengthening - to improve esthetics and provide adequate
retention when clinical crown is short.
Free autogeneous gingival graft - increase width of inadequate attached gingiva
caries,
decalcification,
erosion,
attrition,
abrasion,
exposed root
surface or
fractures -
restore where
required.
Elective
endodontic
treatment may
be necessary for
supraerupted or
malaligned teeth
post and core
Infected root pieces, hopelessly mobile teeth and impacted or unerupted supernumerary
teeth are removed.
Block resection and movement of both maxillary and mandibular segments
Elective soft tissue surgery ,alteration of muscle attachments and alveoplasty
32
33. Amelogenesis
Imperfecta in a child
impair correct
relationship between
maxillary and
mandibular teeth.
adverse psychological
effect
Postponing
treatment
until
adulthood
IMPORTANCE OF IMMEDIATE
TREATMENT
Ni-Cr crowns
are placed on
first permanent
molars and
second
deciduous
molars to
stabilize
occlusion and
halt attrition.
Vertical
dimension is
not altered.
As anterior
teeth and
premolars
erupt,
polycarbonate
resin crowns
are given
After all
permanent
teeth are
erupted, these
restorations
serve as
transitional
treatment
until
adulthood
33
34. Vertical Dimension: The distance between
two selected anatomic or marked points, one
on a fixed and the other on a movable
member.
Vertical Dimension of Rest: The postural
position of the mandible when an individual
is resting comfortably in an upright position
and the associated muscles are in a state of
minimal contractual activity.
Vertical Dimension of Occlusion: The
distance between two selected anatomic or
marked points when in maximal intercuspal
position.
35. Dawson P E. Evaluation, diagnosis and treatment of occlusal problems. pp 280-285. St Louis, MO: CV Mosby, 1989.
UNDERSTANDING VERTICAL
DIMENSION
• You cannot determine vertical dimension based on whether the patient is
comfortable.
• Measuring the freeway space is not an accurate way to determine the correct
vertical dimension of occlusion.
• Determining the rest position of the mandible is not a key to determining
vertical dimension.
• Lost vertical dimension is not a cause of temporomandibular disorders.
36. The mandible-to-maxilla relationship,
established by the repetitive contracted
length of the elevator muscles,
determines the VDO.
Dawson P E. Evaluation, diagnosis and treatment of occlusal problems. pp 280-285. St Louis, MO: CV Mosby, 1989 page number 115
The teeth continue
to erupt until they
meet an opposite
force of equal
intensity to the
eruptive force.
The jaw-to-jaw dimension is maintained with such consistent
muscle contraction length that even rapid abrasive wear does not
cause a loss of vertical dimension (A). The alveolar process lengthens in an
amount equal to the wear.
37. METHODS OF DETERMINING
VERTICAL RELATION
Abduo J, Lyons K. Clinical considerations for increasing occlusal vertical dimension: a review. Australian dental journal. 2012 Mar;57(1):2-10.
38. Calliper Method Willis gauge Boley gauge
Geerts GA, Stuhlinger ME, Nel DG. A comparison of the accuracy of two methods used by pre-doctoral students to measure vertical dimension. The Journal of prosthetic dentistry. 2004 Jan 1;91(1):59-66.
39. Can vertical dimension be altered?
• As the teeth wear or become abraded, the teeth and alveolar bone elongate through growth to
maintain the original vertical dimension with the maintenance of the same closest speaking space.
However, occlusal wear may occur more rapidly than continuous eruption depending upon the
etiology of the wear.
Sicher(1949) and Silverman42(1952)
• Treatment of reduced vertical dimension is not designed to increase the vertical dimension beyond
the normal, but is intended to restore the amount of vertical dimension that has been lost. A young
person will tolerate a greater correction of vertical dimension and become adjusted more easily to
a reduction in the interocclusal distance
Harry Kazis and Albert Kazis
• Closest speaking space can range from 0 to 10mm in different patients and that there is no average
closest speaking space. But it is constant in an individual. Vertical dimension must not be increased
beyond the normal for each patient. . It is better to use a vertical dimension that is too small than
to use one that is too great
Silverman(1956)
39
40. • stated that increasing the vertical dimension places the muscles of mastication
and temperomandibular joint under strain. The crown to root ratio is also
affected and hence ‘bite raising’ is contraindicated
Landa(1955)
• even when the teeth have grown down to the gum line the vertical dimension is
not lost because of the eruption of the teeth along with the alveolar bone.
• It is not practical to restore severely worn dentition without restoring the
vertical dimension to obtain space for the restorative material, the dimension
can be increased to 1-1.5 mm.
• The potential problems of restoring the vertical dimension are clenching,
muscle fatigue, soreness of teeth, muscles and joints, headache,intrusion of
teeth, fracture of porcelain , occlusal instability due to shifting of restored teeth
and continual wear.
• Checking and periodic occlusal adjustment must be done upto a year before
normal stability returns.
Dawson(1974)
40
41. When Must The Vertical
Dimension Be Changed?
• Extremely worn dentition
• Crown lengthening vs. increasing
the VD
• Restoring severe arch mal-
relationships
• Extreme occlusal plane problems
• Anterior open bite
Why Not Increase The VD?
• Any disharmony in the system provokes
adaptive responses designed to return the
system to equilibrium.
• Adaptive process is not always predictable.
• No benefit over time to the patient whatsoever.
• The goal of occlusal therapy is to minimise the
requirements for adaptation.
• Segmental - instability of the entire occlusal
harmony.
41
42. Methods of
obtaining space
for restoring
worn teeth
Selective grinding
• Badly worn anterior teeth that have drifted into
anterior wear end to end relationship
• Posterior teeth that interfere, deflect the mandible
forward and cause excessive wear on upper anterior
lingual incline.
• Interferences should be eliminated by selective
grinding so that mandible can close at centric relation
42
Equilibrate Reposition Restore Osteotomy Orthognathics
Bloom DR, Padayachy JN. Increasing occlusal vertical dimension—Why, when and how. British dental journal. 2006 Mar;200(5):251-6.
43. Periodontal surgery
• Includes gingivoplasty, osteoectomy
to gain clinical crown length is
sometimes required for retention
and esthetics.
• 2-3mm of supporting bone can
usually be removed without
jeopardizing periodontal support.
43
44. • There are occasionally
situations where
restoration of a worn
dentition can be
accomplished only by
increasing occlusal
vertical dimension, even
though a loss of vertical
dimension is not
diagnosed
Splints and provisional restorations
Removable
occlusal splint
• Given for 6-8 weeks
Evaluated for
comfort and
function
Teeth preparation
and provisional
fixed restorations
• Evaluated for 2-3
months
If deemed absolutely necessary, modification of
vertical dimension should be accomplished through
cautious trials with removable occlusal splints
44
45. Dahl appliance
• Partial coverage splint, 2-4 mm thick,
designed to depress the opposing teeth
against which it contacts and to allow
the unopposed teeth to overerupt.
• It contacts anterior teeth and allows
posterior teeth to erupt.
• Alveolar remodeling ensures that
anterior teeth are not intruded into the
bone, with a resulting loss of crown
height
Poyser, N., Porter, R., Briggs, P. et al. The Dahl Concept: past, present and future. Br Dent J 198, 669–676 (2005). https://doi.org/10.1038/sj.bdj.4812371
45
46. • Dahl described the use of
cobalt chromium appliance
but its modifications of acrylic
and bonded composite have
been used satisfactorily.
• Most space is created between
2-4 months of continuous
wear
46
47. Centric Relation
• It is defined as the maxillo-mandibular 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 articular eminences.
• This position is independent of tooth contact
47
Centric relation is the only
condylar position that permits an
interference-free occlusion
48. Methods available to guide the mandible into
centric relation
1.Chinpoint Guidance method or
one handed technique- Guichet
• It places the condyles in most posterior and
superior position which can result in trauma to
TMJ.
• not advocated.
2. Unguided method
Brill introduced a muscular position which allows
patient’s natural muscle functions to position the
mandible into centric relation position.
3. Bilateral manipulation method
• Dawson introduced this method in
which the condyles are in their most
superior position in the gleoid fossa.
• Firmness of upwardly directed
pressure at or near the angle of the
mandible to ensure that the condyles
are seated seated againt the eminence
Brit Dent J.1959, vol 106, pg 391-400
48
49. 49
Taking centric bite records
1.the ability of the
operator to manipulate
the mandible
2.the ability of the
patient to co-operate
3.tooth mobility 4.edentulous area
5.condylectomy
6.Occlusal
interferences
Factors
considered
while making
interocclusal
records
Purpose:to capture ,in some stable material ,the relationship of the mandible to the maxilla when the
condyles are in their terminal axis position
4 Basic
techniques
1.Wax bite
procedures
2.Anterior
stop
techniques
3.Use of
preadapted
bases
4.Central
bearing point
techniques
50. Wax bite procedure
• Most popular procedure (simple)
• Extra hard baseplate wax is an excellent bite
material
• When it is warm it becomes soft enough not
to cause movement of teeth.
• It should be brittle and not bend to mould
itself to fit the models as it will mask the
errors if not rigid.
• This method is not suitable for patients
having extremely mobile teeth or large
edentulous area.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.93
50
51. Anterior stop technique
• Extremely accurate
• Allows the condyles to seat up without any possible deviation from
posterior teeth.
• When mandible is closed the lower incisors strike against a stop that
is precisely adapted to fit against the upper incisors
• thin enough so that the first point of posterior contact just barely
misses
• Anterior stop may be made from acrylic or hard compound
Very loose teeth
Posterior
edentulous ridges
Patients with
temporomandibular
joint problems
51
52. Mandibular deprogramming
Ask the patient to bite on these with anterior teeth for 5 -10 minutes.
• The memory position of teeth intercuspation is lost
1) Cotton role
2) Anterior Jig
3) Leaf Guage
52
53. Anterior bite stops/
Jig
• Anterior jig prevents posterior teeth from occluding and thus disrupts
the proprioceotive memory.
• As the anterior stop is rigid on contact with lower incisor teeth, anterior
resistance is created and a mandibular leverage is created with naturally
braced tripod effect along with two condyles.
• Jig breaks the patient’s habitual closure pattern and acts as the third leg
of the tripod by creating resistance while stopping the closure.
Principle
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.81
53
54. Fabrication of anterior jig
• Compound is softened and added to upper incisors so that their lingual surfaces
are completely covered
• The patient closes into the compound until the posterior teeth barely miss the
contact while in supine position the lower central incisors contact the smooth
lingual incline of the jig at only one point.
• The jig incline must stop the mandible before posterior tooth contact and should
be angled 45-60 degrees posteriorly and superiorly from the occlusal plane.
• The jig can also be made of autopolymerizing acrylic resin on mounted casts and
then adjusted intraorally.
• After the jig is made posterior bite record is taken
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.81
54
55. 55
Leaf Gauge – Dr James.H.Long (1973)
• uniform 0.1mm thickness which are sequentially numbered
Most useful and practical
alternative to anterior jig
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.82
Repeated after adding a leaf guage until the patient can close for 2-5 minutes without feeling a posterior tooth contact.
patient can feel a posterior tooth contact in 15- 52 seconds after the jaw is closed with a ‘half hard’ closing force.
Leaves are added or subtracted until patient can barely feel a posterior tooth touch while closing firmly on leaf guage.
close on back teeth until lower incisors touch on back side of leaf guage.
Arbitary number of leaves are placed at the maxillary anterior midline parallel to the lingual plane of central incisors.
56. Power Bite
• Proper use requires precise location of centric relation before closing power from the elevator
muscles is applied.
• starts with a bite record made between the upper and lower anterior teeth.
• a softened compound that hardens after the indentations have been made between the upper
and lower anterior teeth.
• Closure of the jaw must stop short of any posterior tooth contact.
• patient is then instructed to clench tightly to seat the condyles up into centric relation.
• The problem is that if the anterior segment of the bite is made with the mandible displaced
from centric relation, the hardened material locks the jaw into that relationship and prevents
the condyles from moving back and up
56
57. Use of preadapted bases
• Indicated whenever there is
a danger that teeth will
move or soft tissues be
compressed by the bite
record
• Heated strip of dead soft
wax should be added over it
in edentulous region to
indent the lower teeth in
centric occlusion without
tooth to tooth contact
It is made with triple layer of extra hard
baseplate wax adapted on an accurate model,
usually of the upper arch to avoid
dislodgement by the tongue
57
58. Manipulated centric relation closure can bring the lower anterior
teeth into contact with the wax.
While holding the TMJs firmly on their centric relation axis, ask the patient
to lightly bite into the wax to form shallow indentations.
Then chill the wax to harden it and add the putty silicone to the preformed
wax base.
Manipulate a verified centric relation and close into the indentations.
The soft putty silicone will adapt to the opposing ridge
58
59. Central bearing point technique
• It enables free movement of the mandible without
influence of teeth proprioceptives.
• Drawback is that vertical dimension must be increased
considerably to accommodate the clutches and bearing
point apparatus.
• If the terminal axis is not recorded precisely it will
result in mounting error.
If a central bearing point
apparatus is adapted to well-fitted
upper and lower clutches, all
occlusal contact can be
disengaged.
The bite record is
made between
the clutches
rather than
directly between
opposing teeth.
59
60. Long centric / Freedom in centric
• Defined as ‘ freedom to close the mandible either
into centric relation or slightly anterior to it without
varying the vertical dimension of occlusion.
• When interference in centric relation is eliminated by
equilibration ‘long centric will usually be provided
automatically.
• The most important aspect is that the vertical
dimension of occlusion must be the same from back
to front of each long centric contact area.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.190
60
61. Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.192,193,195
Contact in centric relation Clearance for long centric
61
62. Procedure
• To determine the patient’s long centric two different colours of marking
ribbon are used
• green or blue or black -centric relation points
• Red ribbon -closure from postural rest position
• knife edge inverted cone carborundum stone is used for accurate grinding
• There are no contraindications for providing the freedom.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.196
62
63. 63
• terminal hinge closure and light closure from rest are identical
1.Red mark covered by Green
• Shows a need for long centric
• Should not grind the green centric marks equilibration complete when there are no red marks on the inclines
• In perfected occlusion the red marks will still extend forward from green but at the same VD
2.Red mark extend forward from green centric mark
• Dentist has not correctly manipulated the CR
3.Red mark extend forward from green
• The equilibration is incomplete
• Teeth with some degree of mobility are being move when patient taps
• To check mobility different color ribbon should be used for comparing light contacts from firm contacts
4.Green centric marks missing from red marks
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.196,197
64. Symptoms indicating
requirement of long centric
• Patient says they are
comfortable when lying down
but interfere while sitting up
• Patient says teeth fit fine when
dentist pushes the jaw back
but hit only on front teeth if
close it themselves
Advantage of long centric
• Freedom of movement in centric
occlusion provides patient
comfort and reduces the tendency
to bruxism and other
traumatogenic influence on the
supporting structures.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.191
64
66. 66
The centric relation contacts
• The most critical tooth contour in
the entire occlusal scheme is also
the most universally mismanaged.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.164
67. Upper half of labial surface
• second most important determination
is upper incisal edge position.
• will not be precise until the upper half
of the labial contour has been
determined.
• There is no bulge in nature from the
alveolus to upper labial surface ie the
upper half of the labial surface is
continuous with the labial surface of
the alveolar process
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.164
67
68. Lower half of labial surface
• two planes - for incisal position and to allow
the lip closure path to slide along the labial
surface hence the need to roll in the incisal tip.
• very important step in determining horizontal
position of the incisal edges
• lower lip can easily slide by the incisal third to
seal contact with the upper lip - lip-closure
path.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.165
68
69. Incisal edge
• This should rest along the inner vermillion
border of the lower lip and is best determined
by observing the patient to counting from 50 to
55 ie 'F' sound. This needs to be in harmony
with the neutral zone, lip closure path,
phonetics, envelope of function and aesthetics.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.167
69
70. Anterior guidance Contour of the lingual surface
from the centric stop to the
gingival margin:
• There should be no interferences
with the 'T', 'D' or 'S' sounds.
This is determined by the protrusive path
but should include a 'long centric' that allows
a little freedom before this path is engaged
and so the lower incisors are not bound in
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.167
70
71. Restoring lower anterior teeth
• Lower incisal edges are the
starting point for anterior
guidance and “the view”
when speaking.
• The arrangement of the
entire occlusal scheme starts
with the lower anterior teeth
5 important goals
1. Esthetics
2. Phonetics
3. Occlusal plane
4. Anterior guidance
5. Stability
71
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.179
72. 72
The height of the incisal plane
In ideal instances, the lower
incisal edges form a continuous
gentle curve that is an extension
of the posterior occlusal
plane
Lips sealed
The lower incisal edge is at the height of the
juncture of the upper and lower lips when the teeth are
together. On a lateral cephalometric radiograph, this usually
positions the incisal edge slightly above the functional occlusal
plane.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.183,184
73. 73
• Speaking • Smiling • Lips slightly parted
“The view” when speaking is of
the incisal
edges of the lower anterior teeth.
A varying amount of labial
contour may also be on display.
The upper teeth are usually
hidden during speech.
Only the upper anterior teeth
are typically on
display during smiling. The
lower incisors are usually
hidden during a big smile.
When the jaw is at rest and the lips
are slightly parted in a half smile, both
upper and lower
labial surfaces are about equally on
display.
74. 74
Lower incisal edge contours
The most important contour on the
lower incisal edges is the
labio-incisal line angle.
The “leading edge”
is important for natural appearance
but also to achieve a stable
holding contact against the upper
lingual stop.
Use of the Esthetic Checklist reminds
the technician to do this on every
lower anterior restoration
75. 75
The entire occlusion can be compromised
by instability if lower incisal edges are not
correct.
It is a critical point for analysis and
treatment of anterior teeth
76. Determining plane of
occlusion
2 basic requirement
• Permit anterior guidance to
disocclude posterior teeth
when mandible is protruded
• Permit disclusion of all the
teeth on balancing side when
mandible is moved laterally
Curvature of anterior teeth
determined by-
Establishing correct
• smile line
• proper phonetics
• Anterior guidance
76
77. CURVATURE OF POSTERIOR TEETH
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.401
77
78. Establishing plane of occlusion
3 practical methods
• Analysis on natural teeth through selective
grinding
• Analysis of models with fully adjustable
instrumentation
• Use of Pankey- Mann –Schuyler methods
of occlusal plane analysis.
78
79. SOPA-simplified occlusal plane analyzer
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.401
79
80. Broadrick occlusal plane analuser
• The Broadrick flag accomplishes the same occlusal analysis
on almost all types of semiadjustable articulators.
(1) Card Index 142-101, (1) Bow Compass
142-1001 with
graphite leads, an extra center point and a
needle point, (1)
Scribing Knife 142-3201 and (12) Plastic
Record Cards 142-
3401
Card index 142-101
Bow
compass 142-
1001 with
graphite leads
80
81. .
Maxillary cast mounted by
Facebow transfer
mandibular cast mounted in
centric relation
The accessory
Hanau-Mount Split-
Cast Mounting Plate-
This split cast allows
rapid cast removal
and accurate
replacement during
the survey. visual
guide for adjustment
of the Articulator to
protrusive or lateral
interocclusal relation
records
Place the Card Index onto the Upper
Member
with the open end around the incisal pin
and the slot on
the side around the mounting plate
thumbscrew.
Orbitale Indicator be mounted to the articulator, it
must me removed in order to mount the Card Index
Tighten the
thumbscrew to hold the Card
Index in place
Press a Plastic Record Card over the dowels on the
right
side of the Card Index.
The Cards are matte finished on both
sides and readily accept pencil or ink markings.
81
82. • An average of a 4" radius may be
used in the majority of surveyed
cases.
Variation is necessary only when
pronounced Curve of Spee - 3-3/4"
radius
flat Curve of Spee may require - 5"
radius.
The relatively small divergence between arcs of 3-3/4",
4" and 5" radii over the functional occlusal surfaces on
the lower posterior teeth
82
83. This point must be selected as the most desirable to “Beam” the line and
plane of occlusion posteriorly.
Once selected, it is marked on the cuspid and NOT CHANGED
Position the center point of the Bow Compass on the anterior survey point
(A.S.P.) which is usually the disto-incisal
of the cuspid,
If the cuspid is worn flat, the A.S.P.
may be at the incisal edge
With the center point of the Compass positioned on the
A.S.P., apply a long arc (about 3”) on the Plastic Record
Card.
The occlusal plane survey center (O.P.S.C.) will ultimately
be located on some point on this arc
83
84. .
Select the posterior survey point (P.S.P.) at the distobuccal cusp of
the last lower molar
replace the upper cast and place soft
modeling compound over the lower
ridge
Close articulator until the Incisal
Pin contacts the Incisal Guide in a
centric relation
Chill the compound and carve away
the excess, leaving only compound
contacting into the upper fossae
simulating the lower buccal cusp
No molars in
the
mandibular
arch
Remove the upper cast and select a P.S.P. on the modelling
compound in the same manner as the P.S.P. was selected on the last
molar
Position the center point of the Bow Compass
on the P.S.P.
and apply an arc to intersect the arc from the
A.S.P. as
illustrated.
84
85. Alternate to the molar P.S.P. is a position on the
Condylar
Element of the Articulator, at its anterior
intersection with
the Condylar Shaft
Position the center point of the Compass on this
condylar posterior survey point (C.P.S.P.) and apply
an arc to intersect the arc formed from the A.S.P
Continue with by substituting the needle point for the graphite lead.
85
86. Place the center point of the Bow Compass, still adjusted to the 4”
radius, at the intersection of arcs on the Plastic Record Card (initial
occlusal plane survey center).
Sweep the the needle point over the occlusal surfaces of the
lower posterior teeth to see how the arc conforms to the
existing occlusal plane.
Shift this occlusal plane survey center (O.P.S.C.) on the
long arc on Plastic Record Card, the A.S.P. line, until the
most acceptable line and plane of occlusion is found.
86
87. By trial and retrial, in ideal survey center forming the most
acceptable line and plane of occlusion will be located
• move the
center point
anterior to the
arc intersection
To raise the
line and
plane of
occlusion at
the distal end
• move the point
posterior of
the
intersection.
To lower the
line and
plane of
occlusion
The center point of the Bow Compass is now pierced into this
ideal O.P.S.C. on the Plastic Record Card and circled with pencil
or ink for subsequent relocation.
It may be advantageous to mark “R” (right) in the upper corner
of the Plastic Record Card for identification
A Plastic Record Card is then
place over the dowels on
the left side of the Card Index
and marked “L”. Repeat the
survey procedure
87
88. Measurement of difference between survey lines of
different radii of curvature
Various survey lines obtained from different radii
of curvature
88
89. Posterior occlusion
• Posterior teeth should have equal
intensity contacts that do not
interfere with either the
temporomandibular joints (TMJs)
in the back or the anterior guidance
in the front.
• The requirements for perfected
posterior occlusions start with the
lower posterior teeth.
Three key determinants
1. Plane of occlusion
2. Location of each lower buccal
cusp tip
3. Position and contour of each
lower fossa
89
90. Placement of Lower Buccal Cusps
• determined on the basis of providing the optimum effect for buccolingual stability,
mesiodistal stability, and noninterfering excursions.
• Upper central groove position is analyzed.
• On each upper occlusal surface, a line is drawn from mesial to distal in the central groove.
• The ideal contact point for each lower buccal cusp tip is usually located somewhere on this
line.
• In some tilted teeth, it is advantageous to move the central groove to gain better direction of
forces through the long axis.
• If moving the central groove will enable the stresses to be directed more nearly through the
long axis of any upper tooth, the improved central groove position should be so noted on
the upper cast by drawing a new line.
90
Buccal cusp placement for buccolingual stability
91. 91
• A mark is made on each lower tooth to
indicate the position of the buccal cusp
that would be optimum for buccolingual
stability and direction of force
• Alignment of the optimum lower buccal
cusp position against optimum upper
central groove position is evaluated.
92. Mesiodistal placement of lower buccal cusps
• The best mesiodistal stability is attained by
placement of the lower buccal cusps in
upper fossae.
• Placement in the fossae directs the stresses
properly through the long axis, eliminates
any possibility of plunger cusp food
impaction at contact, and is stable.
• There is no tendency for cusp tips to
migrate out of properly contoured fossae
92
93. Locating the lower buccal cusps
for noninterfering excursions
• Determining which fossa the lower
buccal cusp should contact depends on
where the cusp travels when it leaves
centric relation.
• The mesiodistal placement of each
lower buccal cusp is determined when
one locates it in the fossa that permits
excursions from centric relation
without interference
Contouring cusp tips
93
94. 94
• Placement of lower lingual cusps
• In normal tooth-to-tooth relationships,
the tip of the lower lingual cusp never
comes in contact with the upper tooth.
• Even though the buccal incline of the
lower lingual cusp can be made to
contact in working excursions
• act as a gripper and a grinder by
passing close enough to the upper
lingual cusps to aid in tearing,
crushing, and shearing the food that is
caught between the opposing surfaces.
• The position of the tip should have
enough lingual overjet to hold the
tongue out of the way, but it should
always be located over the root, within
the long axis.
• The measurement between buccal cusp
tip and lingual cusp tip should not be
much greater than half of the total
buccolingual width of the tooth at its
widest part.
• lower lingual cusp height should be
about a millimeter shorter than the
buccal cusp.
• Cusp height can be lowered further in
the first premolar
95. 95
Countouring the lower fossae
• As the mandible moves right or left
from centric relation, its front end
should be guided down the lingual
incline of the upper canine.
• When it serves as the lateral
anterior guidance, the lingual
incline of each upper canine
dictates the fossa contour of each
lower incline that faces it
96. If Only Lower Posterior Teeth
Are to Be Restored
• Cusp tip position and fossa contours
for lower posterior restorations are
aligned and contoured in relation to
the existing upper teeth on the
opposing cast.
• Lower fossa contours will be
established to conform to the upper
lingual cusps.
• Fossa walls can be carved to be
discluded by the anterior guidance
without complication.
If Both Upper and Lower
Posterior Teeth Are to Be
Restored
• If posterior disclusion is the goal, it is
easily achieved by making fossa walls
flatter than the lateral anterior guidance,
and establishing an acceptable occlusal
plane that permits the anterior guidance to
disclude the posterior teeth in all
excursions.
• After the anterior guidance has been
finalized, the simplest method for ensuring
that fossa walls will be discluded in lateral
excursions is through the use of a
fabricated fossa contour guide.
96
97. Determining and Carving
Lower Fossa Contours
Purpose
• to ensure a noninterfering
accommodation for the upper
lingual cusps.
• It will provide a fossa contour that
is compatible with the lateral
anterior guidance regardless of the
contour of the anterior guidance.
• It can be easily modified to provide
extra freedom.
Fossa contour guide
• can be used in any stage of wax-up or
even porcelain application.
• used only if both upper and lower
posterior teeth are to be restored
• The anterior guidance must be correct
before the guide is fabricated or before
occlusal contours can be determined
for lower posterior restorations
97
98. 98
Making the fossa contour guide
• The anterior guidance may
be corrected in provisional
restorations, and a centrically
mounted cast of the
provisional restorations in
place may be used to
determine the allowable
fossa-wall angulation for the
posterior restorations.
• The guide is usually made
when the casts are mounted,
but it is not used until the
posterior wax-up is done or
the porcelain is being applied
and contoured.
• Step 1
The regular incisal guide pin is removed and replaced with
the special fossa-contour pin. The blade of the pin is indented into
a mound of wax on a flat plastic guide table
99. 99
The upper bow is moved into left and right
excursions, allowing the contours of the lateral
anterior guidance to determine
the path that the guide pin cuts into the wax.
When the lateral guidance paths have been cut
sharply into the wax, the special pin is raised. It is then used to hold
a handle for the fossa guide. Make the handle by cutting off the tip
of a plastic protector for a disposable needle. The large end fits
snugly onto the raised special pin.
100. 100
Resin is wiped into the hollow end of the handle, and
the pin is lowered so that the two portions flow
together. The resin is allowed to set hard. The guide
can then be removed. The wax on the guide table is
then no longer needed, and so it can be cleaned off
after the guide is removed.
A creamy mix of self-
curing acrylic resin is
flowed into the
indentation in the wax.
Because of the design of the special
wax-cutter pin, the lateral anterior
guidance angle will be evident as a
sharp line running
along the bottom edge of the acrylic
guide. The edge is marked with a
pencil, and any excess acrylic resin
may be ground off in front of the
line.
101. 101
One may actually hollow-grind the front
surface down to
the line to make a scoop-shaped guide,
which is excellent for shaving
out wax from the fossae.
To ensure posterior disclusion, the
fossa walls
must be flatter than the lateral
anterior guidance, so the fossa guide
angle is flattened on the sides and
the tip is rounded to a more
opened-out fossa.
The fossa guide can be used to
contour the wax
patterns or as a guide for shaping
occlusal surfaces in porcelain.
The tip of the guide should be able
to touch the base of the fossa
without interference from the walls
of the fossa.
102. Carving the marginal ridges
• The ridges should be contoured to
reflect food away from the contact,
which means directing it into the
fossae.
• Sluiceways should provide an
escape route for the bolus out of
the fossae toward the lingual as the
stamp cusps crush the food against
the fossae walls.
Countouring ridges and grooves
• work out the fossae contours first and
then functionalize and beautify the
anatomy by placing the appropriate
grooves at the working, protrusive, and
balancing excursion.
• There can be no entanglement of cusps in
grooves that have been made into inclines
that are already out of reach.
• Other grooves may be added as desired to
improve esthetics or to provide more
ridges for better masticatory function
102
103. 103
Upper posterior teeth
• last segment to be restored. It is the fixed posterior segment, and its cusps, inclines,
grooves, and ridges are placed and contoured to accommodate the many border
movements of the lower posterior teeth.
• If the upper contours are determined by the paths of the lower posterior teeth, both
the form and the paths of the lower teeth should be finalized before the upper teeth are
restored
104. LENGTH OF GROUP FUNCTION
CONTACT IN WORKING EXCURSION
• If we elect to provide group function on the working side, we should be aware that
all teeth do not stay in excursive contact for the same length of stroke.
• As the mandible starts its move to the working side, all of the posterior teeth may
contact in harmony with the anterior guidance and the condyle.
• As the mandible moves further to the side, the first teeth to disengage from contact
are the most posterior molars.
• The disengagement is progressive, starting with the back molar, which has the
shortest contact stroke, forward to the canine, which has the longest contact stroke
104
Balancing inclines must be relieved
on all natural teeth
regardless of the method used to
record the border
movements.
105. Types of posterior occlusal contours
There are three basic decisions to make regarding the design of posterior
occlusal contours:
1. Selection of the type of centric relation contacts
2. Determination of the type and distribution of contact in lateral excursions
3. Determination of how to provide stability to the occlusal form
105
106. Occlusal considerations in full mouth rehabilitation
• There is no one type of occlusion that is optimum for all patients.
• The starting point in designing occlusal contours is to shape and locate the centric
contacts so that the forces are directed parallel to the long axes of the teeth.
• Ideal occlusion can be defined as an occlusion compatible with the stomatognathic
system, providing efficient mastication and good esthetics without creating
physiologic abnormalities ( Hobo)
106
107. 107
Types of centric holding contacts
• Centric relation contact is usually established on restorations in one of three ways:
108. Types of centric holding contacts
• It is stressful and produces lateral interferences and hence it should be avoided
Surface to surface contact/Mashed potato contact
• Contact is made on sides of the cusps that are convexly shaped.
• can be given in posterior disclusion cases where anterior teeth are strong enough.
• cannot be used when posterior teeth are in group function (convex cusps immediately disengage upon leaving
centric relation.)
• It is difficult with achieve with no actual indications and no advantage over cust tip to fossa contact.
Tripod contact
• It provides excellent function, stability, resistance to wear and aids easy to equilibrate by shaping the fossa
inclines without disturbing the centric holding contacts.
Cusp tip to fossa contact
108
109. Determinants of occlusal morphology
Posterior controlling factor
• The steeper the articular eminence,
the steeper path will the condyles
follow during protrusion.
• It is a fixed factor.
Anterior controlling factor
• The steeper the lingual surfaces of
the maxillary anterior teeth, the
steeper and more vertical will be
the movement of the mandible.
• It is a variable factor and can be
altered by the dental procedures.
109
110. Vertical determinants of
occlusal morphology
• Anterior Guidance
• Condylar Guidance
• Distance of cusps from these controlling
factors
• Plane of occlusion
• Curve of Spee
• Bennett movement – Amount, Direction
and Timing
Horizontal determinants of
occlusal morphology
• It includes the relationship that influence the
direction of ridges and grooves on the occlusal
surface. Since the cusps pass between the ridges
over grooves, the horizontal determinants also
influence the placement of cusps
• Ridge and groove direction has the influence of
the following factors
• Distance of tooth from axis of rotation
• Distance from mid-sagittal plane
• Bennett movement
• Intercondylar distance
110
111. Occlusal scheme
Patient presents with Occlusal scheme
Natural canine protected Canine protected
Natural group function Group function
Canine missing or periodontally weak Group function
Opposing complete denture Balanced or monoplane
Where no posterior tooth remaining Canine protected
111
112. Variations of posterior
contact in lateral excursions
• Arch relationship does not allow the anterior guidance to do its job of discluding the
nonfunctioning side.
Group function
• allowing some of the posterior teeth to share the load in excursions, whereas others contact only
in centric relation.
Partial group function
• can be achieved by two different types of anterior guidance: anterior group function and canine-
protected occlusion.
Posterior disclusion
112
Class 1 occlusion with
extreme overjet
Class 3 occlusion with
all lower anterior teeth
outside of the upper
anterior teeth
Some end-to-end
bites
Anterior open bite
contacting inclines must be perfectly harmonized to border movements
of the condyles and the anterior guidance.
Convex-to-convex contacts cannot be used to accomplish this.
113. Anterior group function
1. It distributes wear over more teeth.
2. It distributes the stresses to more
teeth.
3. It distributes stress to teeth that are
progressively farther from the condyle
fulcrum.
convex lateral guidances make it
difficult to accomplish.
Canine-protected occlusion
• all lateral stresses must be resisted
solely by the canine.
• capability of the canine to withstand
the entire lateral stress load without
any help from other teeth.
• Exquisitely sensitive nerve endings
protect the canines against too much
lateral stress by redirecting the muscles
to more vertical function.
113
114. Occlusal equilibration in natural dentition
The term ‘occlusal equilibration’
• refers to the correction of stressful
occlusal contacts through selective
grinding.
• It is a phase of treatment that
eliminates only that part of tooth
structure that is in the way of
harmonious jaw function.
Objectives
• Centric relation occlusion
• Acceptable disclusion of anterior teeth
in harmony with condylar movement.
• Stability of occlusion
• Resolution of temperomandibular
joint symptoms.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.394
114
115. Equilibration procedures
divided into four parts
Eliminating
interference to
terminal hinge
axis closure
Eliminating
interference to
lateral
excursions
Eliminating
posterior tooth
interferences
with protrusive
excursions.
Harmonization
of anterior
guidance
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.395
115
116. 116
Interference to Centric Relation
Centric interference can be differentiated into two types-
• Interference to arc of closure • Interference to line of closure
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.396
As the condyles rotate
on their centric relation
axis, each
lower tooth follows an
arc of closure
Primary interferences that
deviate the condyle forward
produce what is commonly
called an anterior
slide.
primary interferences
that cause the
mandible to deviate to
the left or the right
from the first point of
contact in centric
relation to the most
closed position
117. Note the
freedom to close
either in centric
relation or
in maximal
intercuspation at
the most closed
vertical
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.397,398
Interferences to the arc of
closure
117
118. Interference to the line of closure
1. If the interfering incline causes the mandible
to deviate off the line of closure toward the
cheek, grind the buccal incline of the upper or
the lingual incline of the lower, or both inclines.
2. If the interfering incline causes the mandible
to deviate off the line of closure toward the
tongue, the grinding rule is: Grind the lingual
incline of the upper or the buccal incline of the
lower, or both inclines
118
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.398,399
119. A balancing incline interference that would be easily
missed if the condyles are not held firmly up on the centric relation axis
during closure
When the condyles are
seated, the right molar is the
only contact during closure.
Squeezing the teeth together
shifts the jaw to
the right and causes the left
condyle to displace.
Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.399
119
120. Grinding Rules
Rule 1: Narrow stamp cusps
before reshaping fossae
Rule 2: Don’t shorten a stamp
cusp
120
121. Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.401
121
122. Dawson PE. Functional occlusion-e-book: from TMJ to smile design. Elsevier Health Sciences; 2006 Jul 31. PAGE NO.401
Tilted teeth
Tilted teeth or wide cusp tips can be
adjusted to improve stability
as well as to eliminate interferences. If
the mark on the
upper tooth is buccal to the central
fossa, the buccal surface
of the lower tooth is ground to move
the cusp tip lingually if
the shaping can be accomplished
without shortening the
cusp tip out of centric contact.
Grinding on the upper teeth
only may mutilate upper cusps
unnecessarily
122
123. Rule 3: Adjust centric
interferences first
1. By adjusting centric interferences first,
you have the option of improving cusp-
tip position.
2. When cusp-tip position is given first
priority, occlusal grinding is more evenly
distributed to both arches.
3. If cusp-tip contours and position are
improved first in centric relation,
eccentric interferences can be eliminated
with speed and simplicity.
Rule 4: Eliminate all posterior
incline contacts. Preserve cusp
tips only.
• If all eccentric contacts on
posterior teeth are to be eliminated,
any posterior incline that marks in
any excursion can be reduced.
• Centric stops must be preserved,
but all other contacts can be shaped
so that they are discluded by the
anterior guidance.
123
124. Lateral excursion interferences
• The path that is followed by the lower
posterior teeth as they leave centric
relation and travel laterally is dictated
by two determinants:
1. The border movements of the
condyles, which act as the posterior
determinant
2. The anterior guidance, which acts as
the anterior determinant
2 types
BALANCING
SIDE
BULL
WORKING
SIDE
LUBL
determine type of occlusion
Group Function - posterior disclusion
Cusp tips are centric holding stops hence adjustings to be done on fossa inclines
124
125. PROTRUSIVE
INTERFERENCES
Correction done in case of steep anterior guidance
Grinding rule-DUML
Materials for marking interference
• Ribbons
• Marking paper
• Joffe-marker
• waxes
125
Editor's Notes
Achieving success in full mouth rehabilitation requires a multidisciplinary approach. ultimate goal of any dental treatment is to
The personality of an individual is often judged by his looks.
According to Turner and Missirlain, patients in category 1 show
A decision must be made between a fixed partial denture and removable partial denture; overdenture or overlay denture and also whether the use of implants is advocated.
This decision primarily depends on the number of teeth present, length of the roots and the health of periodontal disease. Treatment plan is divided into-Once all teeth have erupted and adulthood is reached, the size of pulp horns decreases compared to newly erupted teeth.
A definitive treatment can then be planned.
Minor orthodontic tooth movement can significantly enhance the prognosis of subsequent restorative treatment. A tooth can be uprighted, rotated, moved laterally, intruded or extruded to improve axial alignment, create favorable pontic space and direct occlusal forces along the long axis of teeth. The goal of every dentist is to maintain a healthy dentition
From a point on the maxilla to a point on the mandible at the first molar region. Contractile length of elevator muscles – swallow and relax.
Phonetic evaluation.
Closest speaking space.
Facial appearance.
Arbitary increase of occlusal vertical dimension should be avoided
This is evaluated for another 2-3 months before final restorations are fabricated. If there is doubt about complete seating of the TMJ
Long-standing intracapsular disorder that has been resolved.
To stabilize hypermobile teeth and distribute the loading forces over more teeth.
condyle in its dense unyielding disk is stopped by bone.
Only when it reaches that bony stop at centric relation will the inferior lateral pterygoid muscles release their contraction. This is the
key to successful muscle coordination and peaceful function
Variations in technique is the materials
Previously they were made of unexposed X- ray films after developing to remove the emulsion coating.
Clear film was then cut into 1 cm X 5 cm sections. Centric relation interocclusal records
Occlusal equilibration
Relieve painful spasms of lateral pterygoid muscle. convenient and measure the exact vertical opening between the incisors
The bite material is typically a softened compound
that hardens after the indentations have been made by
the anterior teeth. Power bite methods only work if the bite indentations at
the anterior teeth are in harmony with centric relation, or if a
smooth flat surface is used at the anterior segment to permit
free movement of the condyles as elevator muscles contract.
Regardless of the technique or the materials used for making a preadapted base, the base must fit the model perfectly. As long as this criterion is fulfilled, the use of imagination with carefully made bases can solve almost any problem related to making an accurate centric bite record.
Hypermobile teeth or with opposing edentulous ridges; hypermobile teeth are spaced far apart or if the edentulous ridge areas are flabby and mobile.
If the base for the bite record is made on the model that it must fit, the criteria for accuracy can be served quite well - preformed bases
It capacity for stabilizing hypermobile teeth in their correct position while the bite record is being made.
The silicone should then be trimmed back so there is just
a shallow groove for the ridge to fit into (Figure 11-13).
Many different modifications can be made to this technique.
The rule is that the casts must always fit solidly into the bite
record with no rocking
With all possible interferences eliminated, the condyles are free to move into the terminal hinge position while the central bearing point contacts the bearing plate on the opposite arch
When Interferences to CR are eliminated by equilibration Long centric is automatically acquired
Equilibrated patient is free to move into centric or into his original convenience position or any where in between
Freedom to do so the mandible will close directly into centric or a few mm anterior to it , depends on the anatomy and the musculature .
Length of the long centric is determined by the anatomy of the condyle disk relationship.
Equilibration should not cause extensive flattening of the cusps and reduce the efficiency of chewing for that careful use of small stones on the interfering inclines only has to be used
Indicate thatReading the marks
A Long Centric is not essential in these casesVD will slightly open posteriorly but very minimally
By preparing all posterior teeth all possibilities of interferences are eliminated then all that is needed is to correct any inclines on the anterior teeth that cause a deviation from terminal hinge closure.
Properly adjusted centric stops on anterior teeth should be stable enough that not one of the teeth is jarred when the teeth are firmly tapped together in a terminal hinge closure.
If the patient requires the freedom of Long Centric red marks will extend from the green marks.
Occlusal inclines restricting mandibular movement are potential stress producers
The first decision determines the relationship of the
lower incisal edges to the upper anterior teeth (Figure 16-3).
It is the surface contour that establishes an ideal holding
contact for the anterior teeth when the mandible is in centric
relation. This is always the starting point for smile design
because it is the beginning point of functional movements
that establish the anterior guidance.
This decision is the only decision that can be determined
almost solely from the articulated casts in centric relation.
Selection of the best treatment choice for accomplishing this
is made by evaluating all treatment options as just described
in the previous example.
Preparing the incisal half of the labial surface first can ensure adequate room for restorative materials.
By sinking the diamond to the full depth of a measured width parallel to the lower plane of enamel surface, the resulting tooth reduction enables the technician to position the incisal edge where it should be
Works with Denar articulators
It is preset to 4”
line drawn on the cast represent an acceptable coclusal plane
This process is used only if the posterior teeth are to be restored .
It is never used to determine whether or not teeth must be prepared
Hanau and denar articulators
The Card Index
works with both Denar® and Hanau™ articulators
. In any event,
After thorough and considered study, this will be the best possible line and plane of occlusion for the lower posterior teeth to harmonize with all other factors
The Scribing Knife, as furnished, is for placement into the Compass for scribing or cutting plaster, compound or wax during the occlusal plane correction. The edge of the
Scribing Knife may be sharpened to individual requirement as the edge supplied may not meet your preference.
The basic rule to follow regarding the buccolingual position of the lower buccal cusp is: The lower buccal cusp must be positioned so that its contact directs the stresses through the long axis of both upper and lower teeth.
When the canine is
not in position to function individually or in group function
as the lateral anterior guidance, the lingual incline of the
most anterior upper tooth that can assume the role becomes
the dictator of the lower fossa inclines facing it. As the lower
posterior teeth follow the mandible down its lateral path, any
fixed upper lingual cusp seated into the lower fossa becomes
an interference if the lower incline is steeper than the upper
guiding incline it faces. from the contact point of each upper lingual
cusp, the lower fossa inclines should be no steeper than the
lateral anterior guidance inclines they face. Any posterior incline
that is steeper discludes the anterior guidance and adds
to its own lateral stress. If the lower cusp-fossa angle is
steeper than the lateral anterior guidance, the upper lingual
cusps will be locked into the lower fossae and the back teeth
will clash stressfully when lateral excursions are made.
To ensure complete disclusion, the
condylar path on the articulator can be set flatter than the patient’s
condylar path. This will guarantee posterior disclusion
when the restorations are placed in the mouth if the master
casts are mounted correctly in a verified centric relation.
If
It can be fabricated by auxiliaries in the office in
just a few minutes. The guide should accompany the articulated
die model to the technician and should be returned
with the finished restorations for use by the dentist in his or
her evaluation of the finalized occlusal contours
The shape of the
special wax-cutter pin will provide for enough thickness of the back
of the fossa guide, so that it will be strong enough to use either as
a guide to check the carving of the fossae or as a convenient tool to
scoop out fossae contours in the wax or the buildup-stage porcelain.
If a rubber band is attached through a hole drilled in the handle, the
guide can be attached to the articulator for convenience. There are three basic rules for using the fossa contour
guide.
1. Always hold the handle perpendicularly (Figure 21-9).
The cusp-fossae angles were related to the handle when
it was straight up and down on the articulator. Tilting the
handle would produce an error in the fossa contours.
2. Never destroy a predetermined cusp tip. The depth of
the fossae will be limited automatically if this rule is
followed (Figure 21-10).
3. Locate fossae in proper relation to cusp tips. A basic
knowledge of anatomy is necessary for all techniques.
Proper location of fossae ensures saucerlike fossae
contours and permits good occlusal form.
When all cusp tips have been properly located and the fossae
correctly placed and contoured, the marginal ridges
seem to fall right into place. The most common error noted
in marginal ridge contouring is failure to evenly line up the
marginal ridges of contacting teeth. Uneven height of adjacent
marginal ridges invites food entrapment and often becomes
an interference. Ridges and grooves give beauty and naturalness to the occlusal
scheme. It is the action of ridges and grooves against
their opponent counterparts that grasps the food and then
crushes, tears, and shreds it as the lower teeth follow their
cyclic paths of function against upper inclines. With proper
occlusal relationships, it is not necessary for the lower teeth
to actually contact the upper teeth in function. The bolus is
nearly disintegrated by the time the first tooth contact is
made, so the arrangement of ridges and grooves is to permit
the cusps to pass close enough to each other to mangle the
food between the grooved surfaces without the need for actual
tooth contact.
Although it is possible to fabricate upper and lower posterior
restorations together, upper posterior restorations
should never be fabricated against lower posterior teeth that
require correction of their occlusal plane, cusp-tip placement,
or fossa contours. If it is absolutely necessary to restore
upper posterior teeth first, the lower teeth should be
corrected as close to optimum as possible with selective
grinding or temporary restorations. It seems most inconsistent
to build errors into restorations that are supposed to last
for many years.
There are three basic ways by which centric contact is usually established.
most practical method for
discluding the posterior teeth when arch relationships and
tooth alignment permit it. Anterior group function is beneficial
in three ways: