This document provides an overview of occlusion in dentistry. It defines key terms like occlusion and discusses concepts of occlusion including bilaterally balanced, unilaterally balanced, and canine guided occlusion. The importance of occlusion is described for various dental specialties like pedodontics, orthodontics, oral surgery, restorative dentistry and prosthodontics. Basic occlusion principles from dental anatomy are covered. The document also discusses types of occlusal errors and their correction as well as Hanau's laws of articulation.

1. OCCLUSION IN DENTISTRY
PRESENTED BY – DR. ANAMIKA ABRAHAM
GUIDED BY – DR. DESHRAJ JAIN

2. TABLE OF CONTENTS
DEFINITIONS
THERAPEUTIC AND PHYSIOLOGIC OCCLUSION
IDEAL OCCLUSION
CONCEPTS OF OCCLUSION
 BILATERAL BALANCED
 UNILATERAL BALANCED/ GROUP FUNCTION
 CANINE GUIDED
OCCLUSION BASICS FROM DENTAL ANATOMY
IMPORTANCE OF OCCLUSION IN
 PEDODONTICS
 ORTHODONTICS
 ORAL SURGERY
 RESTORATIVE DENTISTRY
 PERIODONTICS
 PROSTHODONTICS
TYPES OF OCCLUSAL ERROR AND ITS CORRECTION
PATHOGENIC OCCLUSION
CONCLUSION
REFERENCES

3. Key terms & Definitions
Occlusion: is derived from the Latin word
“Occlusio” meaning act of closure or being
closed.
According to ANGLE “occlusion is a normal
relation of occlusal inclined planes of the teeth
when jaw is closed.
GPT: static relation between incising and
masticating surfaces of maxillary & mandibular
teeth or tooth analogues.

4. “Occlusion is the act or process of closure or
of being closed or shut off”
• Ramfjord and Ash: Occlusion = Contacts
between teeth
• “Multifactorial functional relationship
between the teeth and other components
of the masticatory system as well as with
other areas of the head and neck that
directly or indirectly relate to function,
parafunction or dysfunction of the
masticatory system’’

5. Masticatory
system
Teeth
Periodontium Articulatory
system TMJ
Muscles Occlusion

6. A therapeutic occlusion is one in which the
arrangement of teeth and their opposing
surfaces satisfy functional and esthetic
requirements while distributing and directing
forces of occlusion over as many teeth as
possible during functions of the mandible.
Physiologic occlusion- Occlusion that deviates in
one or more ways from ideal, yet it is well
adapted to that particular environment, is
esthetic and shows no pathologic manifestation

7. Ideal Occlusion
Guichet(1970) described standards for ideal occlusion
and said that there was no one ideal occlusion pattern
for all individuals but an appropriate pattern can be
found based on these criteria.
 Criteria I- Incorporate into the occlusion those factors which have to do
with the reduction of vertical forces.
 Criteria II- Provide a maximum intercuspation of teeth with the condyles in
centric relation position.
 Criteria III- Provide for horizontal movement of the mandible from the
centric position

8. Concepts of the Occlusion
• Historically, the study of occlusion and articulation
has undergone an evolution of concepts.
Bilateral
Balanced
Occlusion
Unilateral
Balanced
Occlusion
Mutually
Protected
Occlusion

9. Bilaterally Balanced Occlusion
 It is based on the work of Von
Spee and Monson.
Teeth should contact in all
excursive positions of the
mandible.
On the nonworking side it’s
important to prevent tipping of
the complete denture.
 Subsequently, the concept was
applied to natural teeth in
complete occlusal rehabilitation.

10. Definition :
• The simultaneous contacting of the maxillary
and the mandibular teeth on the right and left
side and in the posterior and anterior occlusal
areas in centric and eccentric positions,
developed to lessen or limit the tipping or
rotating of the denture base in relation to the
supporting structures.

11.  An attempt was made to reduce the load on
individual teeth by sharing the stress among as
many teeth as possible.
It was soon discovered, however, that this was a
very difficult type of arrangement to achieve.
 As a result of the multiple tooth contacts that
occurred as the mandible moved through its
various excursions, there was excessive frictional
wear on the teeth

12. The Demise Of Balanced Occlusion In
Restoring Natural Dentition
Bilateral balanced occlusion
Fixed Prosthodontics
High rate of failure
Failure was due to
 Increased occlusal
wear.
 Increased/accelerated
periodontal breakdown.
 TMJ and
neuromuscular
disturbances.

13. Unilateral Balanced / Group
Function Occlusion
 In a unilaterally balanced occlusion , excursive
contact occurs between all opposing posterior teeth
on the laterotrusive (working) side only.
 This concept had its origin in the work of Schuyler

14. Definition:-
Multiple contact relations
between maxillary and
mandibular teeth, in lateral
movements on the working
side, whereby simultaneous
contact of several teeth acts as a
group to distribute occlusal
forces.

15. The most desirable group function occlusion
consists of contact of canine,premolar and
mesiobuccal cusp of first molar.
 Any laterotrusive contact more posterior than
mesial portion of first molar are not desirable
because of the increased amount of force that can
be placed as its near the fulcrum and force
vectors .

16. Advantages
 Group function of the teeth on the working side
distributes the occlusal load .
 The absence of contact on the nonworking side
prevents those from getting subjected to destructive
,obliquely directed forces found in nonworking
interferences.

17.  It also saves centric holding cusps that is
mandibular buccal cusps and maxillary palatal cusps
from excessive wear.
 Group function was felt to be goal for occlusal
adjustments and has easy application.
 In the presence of anterior bone loss or missing
canines, mouth should be restored to group
function.

18. Disadvantages:-
Group Function Occlusion doesn’t fulfill criteria for
ideal occlusion

19. Characteristics of Group Function Given by
BEYRON (1954)
 Teeth should receive stress along the tooth long axis
.
 Total stress should be distributed among the tooth
segment in lateral movement.
 No interferences occur from closure into intercuspal
position

20. Mutually Protected Occlusion
 During the early 1960s, this occlusal scheme was
advocated by Stuart and Stallard, based on
earlier work by D’Amico.
 In this arrangement, centric relation coincides with
the maximum intercuspation position.

21. Definition:-
An occlusal scheme in which
the posterior teeth
prevent excessive contact
of the anterior teeth in
maximum
intercuspation, and the
anterior teeth disengage
the posterior teeth in all
mandibular excursive
movements.

22.  Posterior teeth function most effectively
in stopping the mandible during closure
whereas anterior teeth function most
effectively in guiding the mandible
during eccentric movements.
It is apparent that the posterior teeth
should contact slightly more heavily than
anterior teeth in centric relation.

23. Lucia in 1961- Advantages
Minimum amount of tooth contact is involved –therefore
better penetration of food.
 A cusp to fossa relationship produces an interlocking of
upper and lower components- giving a maximum support
in centric relation in all directions.
The force is clearly closer to the long axis of each tooth.
 The arrangement of the marginal,transverse and oblique
ridges have a shearing action -make a more efficient

24. OCCLUSION
BASICS FROM DENTAL ANATOMY

25. Based on arrangement of teeth
Type of occlusal contact:
1. Cusp-fossa occlusion
2. Cusp-embrasure occlusion
Ideal cusp-fossa relationship
• A, Mesiolingual cusp of maxillary first molar occludes in the central fossa of the
mandibular first molar. Distal buccal cusp of mandibular first molar occludes in the
central fossa of the maxillary first molar.
• B, Concept of occlusion in which all supporting cusps occlude in fossae

26. Normal intercuspation of maxillary and mandibular teeth.
1, Central incisors (labial aspect). 2, Central incisors (mesial aspect). 3, Maxillary
canine in contact with mandibular canine and first premolar (facial aspect). 4,
Maxillary first premolar and mandibular first premolar (buccal aspect). 5, Maxillary
first premolar and mandibular first premolar (mesial aspect). 6, First molars
(buccal aspect). 7, First molars (mesial aspect). 8, First molars (distal aspect)

27. Types Of Cusps
Centric holding cusps
 The buccal cusps of the mandibular posterior teeth and the lingual cusps of
the maxillary posterior teeth occlude with the opposing CF areas.
Non supporting cusp
 The buccal cusps of the maxillary posterior teeth and the lingual cusps of
the mandibular posterior teeth are called the guiding or noncentric cusps.

29. OCCLUSAL SURFACE SHOWING
CONTACT POINTS

30. IMPORTANCE OF OCCLUSION

31. PEDODONTICS
• The development of occlusion is the most
dynamic phenomenon in the mouth.
• Development of normal dentition and occlusion
depends upon dentoalveolar , skeletal and the
neuromuscular factors.
• The emergence (eruption) of the primary
dentition into the oral cavity is an important
time for the development of oral motor behavior
and the acquisition of masticatory skills.

32. STAGES OF OCCLUSAL DEVLOPMENT
• NEONATAL PERIOD
• PRIMARY DENTITION
• MIXED DENTITION
• PERMANENT DENTITION

33. FLUSH TERMINAL
PLANE
DISTAL STEP
MESIAL STEP

34. FACTORS AFFECTING OCCLUSAL
DEVELOPMENT
• General factors
▫ Skeletal factors
▫ Muscle factor
▫ Dental factor
• Local factors
▫ Aberrant
developmental position
▫ Supernumerary teeth
▫ Hypodontia
▫ Habits
▫ Localized soft tissue
anomalies

35. RESTORATIVE DENTISTRY
• Occlusal restorations should be such that it provides a definate
centric stop for the opposing cusp at the central fossa
• If the centric stops are on the incline , the teeth are apt to move and
new interferences will be created
• Common mistake is to overcarve the restoration –leading to
interferences in lateral excursions
• Occlusal restorations should have the same hardness and potential
for wear as the teeth
• Faulty interproximal contacts – disturb the occlusal relationship

36. PERIODONTICS
• Abnormal occlusion is a contributary factor in
accelaration of periodontal breakdown
• OCCLUSAL TRAUMA – Defined as injury to the
periodontium resulting from occlusal forces that
exceeds the reparative capacity of the
attachment apparatus.

37. • Occlusion becomes a factor for consideration when the
occlusal forces acting on a tooth produce displacement of
the root in the socket which results in an injury to the
supporting periodontal ligament. This periodontal tissue
injury from occlusal forces has been defined as the lesion
of trauma from occlusion
• The essential requirements for the co-destructive factor
effect are the production of a traumatic lesion
immediately subjacent to an established marginal
periodontitis

38. ORAL SURGERY
• The treatment of maxillofacial fractures usually
requires control of dental occlusion with the
application of wires/arch bars for interdental
wiring to orient and stabilize the fracture
• Important principle which is followed
‘RESTORATION OF PREINJURY OCCLUSION’

39. ORTHODONTICS
Andrews , in 1972, observed the presence of six common
characteristics, known as “six keys to normal occlusion”:
• Molar relationship
• Mesiodistal crown angulation
• Labiolingual crown inclination
• Absence of rotation
• Tight contacts
• Curve of spee

40. In 1976, Roth presented the following functional
aspects of the occlusion as being fundamental for
completion of the orthodontic cases:
1. Teeth must present maximum intercuspal (MI) position with the jaw in
centric relation (CR);
2. In centric relation, all posterior teeth must present axial occlusal
contacts, and the anterior teeth must maintain a distance of 0.0005
inches between them;
3. During laterotrusion, the canines must disocclude the posterior teeth
(canine guidance);
4. During protrusion, the upper anterior teeth must occlude with the
lower anterior teeth and the first premolar or the second premolar (in
extraction cases), aiming at disoccluding all posterior teeth (immediate
anterior guidance);
5. No interference must be present on the balancing side

41. WHY?? canine guidance at orthodontic
completion
1. the strategic positioning of the canine in the arch
2. the favorable root anatomy
3. presence of a better crownroot proportion
4. the presence of dense and compact bone around the root, which better
tolerates the occlusal forces compared with the medullar bone of the
posterior teeth
5. the sensorial pulse that activates less muscles when the canine teeth are
in contact than when posterior teeth contact each other
• Therefore, when the jaw is in a right or left laterotrusive
movement, the upper and lower canines are the appropriate
teeth to contact and to dissipate the horizontal forces, while
promoting the disocclusion of the posterior teeth.

42. • The occlusion school- According to Kingsley,
proper occlusion is a key factor in determining
the stability of newly moved teeth.
THEORIES OF RETENTION - By REIDEL
Theorum 4 – Proper occlusion is a potent factor in
holding teeth in their corrected positions.
Aim of orthodontic treatment is to achieve good
functional occlusion i.e. Harmonious occlusal
contacts during functional movements of the
jaws.

43. CONCEPTS OF COMPLETE DENTURE
OCCLUSION
Static concept
The static relations in occlusion include centric
occlusion, protrusive occlusion, right and left lateral
occlusion. All of these relations must be balanced
with the simultaneous contacts of all the teeth on
both sides of the arch at their very first contact.
The cuspal inclines should be developed so that the
teeth can glide from a more centric occlusion to
eccentric positions without interference and without
the introduction of rotating or tipping forces.

44. Dynamic concept
The dynamic concept of occlusion is primarily
concerned with opening and closing movements
involved in mastication. Jaw movements and
tooth contacts are made, as the teeth of one
jaw glide over the teeth of the opposing jaw.
Movements of the mandible which occur when
the teeth are not in contact are termed as free
movements.

45. RPD opp prosthesis (Tooth/tooth-tissue
supported)
45
Partial
Complete
Centric Eccentric
Working Non-working/Balancing
Simultaneous bilateral contacts of
opposing posterior teeth
Kennedy”s Class III
Kennedy”s Class I
Kennedy”s Class II
Kennedy”s Class IV
Bilateral balanced occlusion in centric and eccentric positions.
Max
Mand
+
+
+
+
contact of opposing anterior teeth in the planned
intercuspal position
occlusion seen in a harmonious natural dentition

46. Hanau’s Laws of Articulation and Hanau’s
Quint.
• In 1925, Rudolph L. Hanau presented a discussion
paper entitled, “Articulation: Defined, analyzed,
and formulated ’’
FACTORS AFFECTING OCCLUSAL BALANCE :
• Condylar inclination.
• Incisal guidance.
• Height of the cusps
• Plane of orientation.
• Prominence of compensating curve.

47. Condylar inclination.
• Hanau states: “the inclination of the condylar
guidance or condylar inclination is a definite ,
anatomical conception.”
• It is the one factor which the edentulous patient
presents and can in no way be modified by the
operator.
• The condylar path is determined on the patient
by a protrusive record and set on the instrument

49. The degree of condylar inclination
registered results from:
1. The incline of the articular eminence of the TMJ.
2. Action of muscles in mandibular movement.
3. Limitations of movements effected by the attaching
ligaments.
Among all the factors condylar inclination is most
important in securing balanced articulation and form
one of the end-controlling factor.

50. Incisal guidance.
• Second end- controlling factor formed by the
inclination of the incisal guide angle.
• Hanau stated “the inclination of the incisal
guidance is given by the angle of the lingual
surface of the incisors with the horizontal plane
of reference”.

51. INCISAL GUIDE ANGLE [GPT9]
1: anatomically, the angle formed by the
intersection of the plane of occlusion and a line
within the sagittal plane determined by the
incisal edges of the maxillary and mandibular
central incisors when the teeth are in maximum
intercuspation
2: on an articulator, that angle formed, in the
sagittal plane, between the plane of reference
and the slope of the anterior guide table, as
viewed in the sagittal plane

55. • With the establishment of two end-controlling
factors, a balanced articulation is obtained when
a harmonious relationship is established
between these two angles and cusp angles.

56. HEIGHT OF THE CUSP
• Hanau states “ The change of the cusp height in
comparison with the masticatory surface
formation as a whole is an auxiliary magnitude”.
• “In the establishment of the balanced
articulation , we are primarily interested in the
length and the inclination of the effective cusp
inclines.”

57. • Cusp height exerts its influence by determining
the range of tooth contact during eccentric
movements.
• The higher the cusp, the longer the effective
tooth incline, and therefore greater range of
tooth contact during eccentric movements.

58. Plane of orientation.
• Hanau states that “ plane of orientation is purely
a geometrical factor. It is a plane assumed to
pass through three dental landmarks or points;
namely, the central incisal contact point and
summits of the mesiobuccal cusps of the
molars”.

60. Compensating curve.
• It is determined by the inclination of the
posterior teeth and their vertical relationships to
the occlusal plane so that the occlusal surface
results in a curve that is in harmony with the
movement of the mandible as guided posteriorly
by the condylar path.

61. COMPENSATING CURVE
1. The anteroposterior curving (in the median plane) and the
mediolateral curving (in the frontal plane) within the alignment of
the occluding surfaces and incisal edges of artificial teeth that is
used to develop balanced occlusion
2. The arc introduced in the construction of complete removable
dental prostheses to compensate for the opening influences
produced by the condylar and incisal guidance’s during lateral and
protrusive mandibular excursive movements

62. • A steep condylar path requires a steep
compensating curve for occlusal balance.
• A lesser compensating curve for the same
condylar guidance would result in a steeper
incisal guidance, which would cause loss of
balance.

64. Occlusion in Implant supported
prosthesis
Factors that give rise to occlusal overloading
• excessive crown-to-implant length ratio
• over-sized occlusal surfaces
• unfavourable direction of axial forces
• cantilever effects

66. Single-tooth implants
Aim –
• to ensure that occlusal loads are directed as much as possible along
the longitudinal axis of the implant
• to ensure that loads are small
• If there is a tooth contact of light or medium intensity in
maximum intercuspation position, a clearance of 30µm
should be left between the occlusal face of the implant
and the opposing arch.

67. • This clearance aims to compensate for the different biomechanics of
the tooth and the implant and to avoid overloading of the implant,
since under heavy loads the tooth may intrude into the alveolus,
whereas the implant-borne prosthesis will not intrude into the bone.
• In protrusive and lateral movements the occlusal face of the implant
should not be loaded, in order to minimise the transverse forces that
can act on implants

68. IMPLANT supported Fixed partial dentures
Occlusion goals will vary depending on
• location (anterior or posterior) and
• on whether it has a unilateral- or bilateral free end

72. IMPLANT PROTECTED OCCLUSION
Given by Misch
Methods to reduce implant overloading :
• narrowed occlusal table,
• reduced cuspal inclination,
• correction of load direction,
• reduced non-axial loading,
• reduced length of the cantilever
• lighter occlusal contacts on implant prostheses

73. FULL MOUTH REHABILITATION
OBJECTIVE
• reconstruction and restoration of the worn out dentition
• maintenance of the health of the entire stomatognathic
system.
Full mouth rehabilitation should re-establish a
state of functional as well as biological efficiency
where teeth and their periodontal structures, the
muscles of mastication, and the
temporomandibular joint (TMJ) mechanisms all
function together in synchronous harmony.

74. The first step before any restorative
treatment is to decide on which occlusal
scheme there are two approaches:
1. Conformative approach
• Indicated when original occlusion is not to be changed and the same patient's
MIP will be used.
• It is recommended when a small restoration or bridge will be constructed or
when there is no need to restore the entire occlusion at once.
• Advised when unprepared teeth provide the MIP and vertical stop. It is the
favoured approach, because it is simple, predictable and safe, as little or no
adaptation of the patient's neuro-muscular system is needed.
• This is true even in the presence of a slight discrepancy between the MIP and
CR.

75. 2.Reorganised approach
• Indicated when construction of a new occlusal scheme is needed.
• The patient's occlusion is altered to a new occlusal scheme using the
CR as a starting point for the treatment position.
• Aim- simultaneous occlusal contacts on both sides of the jaws when
the mandible is in the CR. The occlusion is also designed to achieve
an MIP that coincides with the CR position.
It is considered in the following situations:
■ when the MIP is not satisfactory;
■ when an increase in vertical dimension is required;
■ when full mouth rehabilitation is required to reconstruct a severely
damaged dentition;
■ when a large fixed prosthesis is needed to replace multiple missing
teeth.

76. Sequence of ‘Occlusal Rehabilitation’
1.Quadrant arch technique—
one quadrant is treated at a time. Advantage - the vertical
dimension can be maintained and lengthy appointments are
avoided.
2. Simultaneous arch technique—
maxillary and mandibular arches are reconstructed simultaneously.
The occlusion can be better established, aesthetics achieved is better,
and number of appointments is reduced.
However, this is more complicated, requires a skilled operator and
technician, and may be difficult for beginners.
3. Segmented simultaneous arch technique—
has advantages of the both the above techniques and is able to provide
the best alternative.

77. TYPES OF OCCLUSAL ERROR

78. IN CENTRIC RELATION -3 TYPES
1. Any pair of opposing teeth
can be too long and
hold the other teeth out of
contact
CORRECTION-
• The fossa of the teeth are deepened by grinding so the teeth
will ,in effect telescope into each other.
• The cusps are not shortened

79. 2. Maxillary and mandibular
teeth nearly end to end
CORRECTION-
• Grinding is done on the inclines so as to move the maxillary cusp
inclines buccally and mandibular cusp inclines lingually
• In the process ,central fossa are made broader, the lingual cusp of
the maxillary tooth is made narrow by grinding from lingual side
and buccal cusp of mandibular tooth is made more narrow by
grinding from buccal side
• The cusps are not shortened

80. 3. Maxillary teeth too far buccal in
relation to mandibular teeth
CORRECTION-
• Lingual cusp of the maxillary teeth is made
more narrow by broadening the central fossa
• In effect, the maxillary lingual cusp is moved lingually
and mandibular buccal cusp is moved buccally
• Cusp are not shortened

81. TYPES OF WORKING SIDE OCCLUSAL
ERRORS – 6 TYPES
1. Both the maxillary buccal cusp and lower lingual
cusp are too long
2. The buccal cusp make contact but lingual cusp do
not.
3. The lingual cusp make contact but buccal cusp do
not.
4. Maxillary buccal or lingual cusp are mesial to their
intercuspating position
5. Maxillary buccal or lingual cusp are distal to their
intercuspating position
6. Teeth on the working side may not contact

82. TYPES OF BALANCING SIDE ERRORS –
2TYPES
1. Balancing side contact is so heavy that working
side teeth are held out of contact
2. There is no contact on the balancing side

83. Pathogenic Occlusion
 A pathogenic occlusion is defined as an occlusal
relationship capable of producing pathologic
changes in the stomatognathic system.
 In such occlusions, sufficient disharmony exists
between the teeth and the TMJs to result in
symptoms that necessitate intervention.

84. Hypersensitivity
to light
Headache
Ear ache
Tinnitus
Sensitivity to
noise
TMJ
Problems
Neck pain
Difficulties in swallowing
Bruxism

85. CONCLUSION
The perfection of skill required to provide
sophisticated yet an ideal treatment of
complex occlusal problems may take years to
acquire. However, the minimum expectation of
the competent practitioner is the ability to
diagnose and treat simple occlusal
disharmonies.
85

86. REFERENCE
• Occlusion – Ramjford and Ash
• Textbook of dental anatomy – Wheelers
• Orthodontics The Art and Science – Bhalajhi
• Fundamentals of fixed prosthodontics – Shillingburg
• Contemporary Fixed Prosthodontics – Rosensteil
• Prosthodontic Treatment of Edentulous patients – Zarb Bolender
• Guidelines for occlusion strategy in implant-borne prostheses. A review International Dental
Journal (2008) 58, 139-145
• Present Status of Occlusion and Occlusal Therapy in Periodontics
• Fundamentals of occlusion and restorative dentistry. Part II: occlusal contacts, interferences and
occlusal considerations in implant patients
• Rehabilitation strategies for partially edentulous - prosthodontic principles and current trends
• Implant protected occlusion: A comprehensive review
• Occlusal Concepts in Full Mouth Rehabilitation: An Overview