Occlusion in cd /orthodontic courses by Indian dental academy

OCCLUSION IN
COMPLETE DENTURE
www.indiandentalacademy.com
INDIAN DENTAL ACADEMY
Leader in continuing Dental Education

 Introduction
 History
 Terminology
 Differences between natural and artificial
teeth.
 Requirements of complete denture
occlusion.
1. Philosophy of occlusion
2. Concepts of occlusion
 Balanced occlusion
 Lingualized occlusion

       Monoplane occlusion
       Linear occlusion
       Organic occlusion
       Physiologically generated occlusion
       Neutrocentric occlusion
3.Selection of occlusal scheme

 Occlusion in complete denture with
special situation:-
Single complete denture
 Implant supported complete denture
Maxillofacial prosthesis
Combination syndrome
 Abnormal jaw relations
 Conclusion
 References.

INTRODUCTION
• The study of occlusion and its relationship
to function of the masticatory system has been
a topic of interest in dentistry since many
years. One of the chief aims of preventive and
restorative dentistry has been to maintain an
occlusion that will function in harmony with
the other components of the masticatory
mechanisms, thereby preserving their health
and at the same time providing the optimum,
if not maximum masticatory function.

• Several researchers of science have
engaged their attention to achieve this
objective. The growth and development
and refinement of the present day
gnathoscopes and articulator systems, is
only but one example of the efforts of
these men of science. Tremendous
interest in this area, accompanied by lack
of complete knowledge has initiated
numerous concepts, theories and
treatment methods.

• The first description of the occlusal
relationships of the teeth was made by
Edward angle in 1809.
• Occlusion became a topic of interest
and much discussion in the early years
of modern dentistry, as the restorability
and replacement of teeth became more
feasible. Many authors laid down
theories of occlusion
REVIEW OF LITERATURE:

• Bownwill in 1858 described the
equilateral triangle theory based on
points of occlusal balance. He was the
one who coined the word articulation.
• Spee in 1890 introduced the concept of
curve of spee. Alfred Gysi in 1914
designed first porcelain anatomical
teeth.

• Monson 1918 put forth the spherical
theory of occlusion. Hall gave conical
theory of occlusion.
• Balanced occlusion was based on the
3 theories of occlusion. This concept
advocated bilateral and balancing tooth
contacts during all lateral and protrusive
movements.
• Hanau in 1926 formulated laws of
balanced articulation (called Hanau’s
quint). Stransbury and Kurth were

• Box, miller, sorrin in 1950 pointed out
the importance of balanced occlusion
and emphasized the need for wide
distribution of stresses.
• Sears 1952 published some axioms
for planning complete denture
occlusion.
• Moses 1954 suggested that the
pleasure curve is desirable in allwww.indiandentalacademy.com

• Jakelson in 1955 disagreed with bilateral
balanced theory in all patients.
• Trapazzano in 1963 and Levin in 1978 laid
down laws called triad and quad of
articulation.
• Devan in 1954 suggested the concept of
Neutrocentric occlusion which embodies
the centralization of occlusal forces which
act on the basal seat when the mandible is
in centric relation to the maxilla.

• Organic occlusion concept was put forth
by Stuart, Stallard in 1961 and Thomas in
1967.
• Payne in 1941 and Pound in 1973
described the lingualized concept of
occlusion.
• Swenson in 1964 , Yurkstas in 1968 ,
Bruce in 1971 described methods of
establishing occlusion in single complete
denture.

• Different concepts and opinions have
been expressed by various authors
depending on various tooth forms to
obtain an occlusion, which offers
maximum efficiency within physiologic
limits.

TERMINOLOGIES: -
Occlusion: - The static relationship between the
incision or masticating surfaces of maxillary or
mandibular teeth or tooth analogues.
Articulation: - The static and dynamic contact
between the occlusal surfaces of the teeth during
function.

 Occlusal form: - The form of occlusal surface
of a teeth or a row of teeth.
 Balanced occlusion: - Bilateral,
simultaneous, anterior and posterior occlusal contact
of teeth in centric and eccentric positions.

 Lingualized occlusion: - Form of
denture occlusion which articulates the
maxillary lingual cusps with the mandible
occlusal surfaces in centric working and
nonworking mandibular positions.
 Monoplane occlusion: - An occlusal
arrangement where in the posterior teeth have
masticatory surfaces that lack any cuspal
height.

 Incisal guidance angle: - Angle formed by
the intersection of plane of occlusion and a line
with in the sagital plane determined by incisal
edges of maxillary and mandibular central incisors
when teeth are in maximum intercuspation.
 Condylar guidance angle: - Angle formed
by the inclination of condylar guide control surface
of an articulator and a specific reference plane.

DIFFERENCE BETWEEN NATURAL AND
ARTIFICIAL OCCLUSION:-
• The teeth in natural dentitions are retained by
periodontal tissues that are innervated by
proprioceptive fibers. In edentulous mouths
both occlusion and proprioceptive feed back
mechanisms are lost. In complete denture
occlusion all the teeth are on bases seated on
movable tissues.

• In natural dentitions the teeth receive
individual pressures of occlusion and can
move independently to adjust to occlusal
pressures. The artificial teeth move as a unit
on a base.

• Malocclusion of natural teeth may be
uneventful for years. Malocclusion of
artificial teeth evokes an immediate
response and involves all of the teeth and
the base.

• Nonvertical forces on natural teeth during
function affect only the teeth involved and are
usually well tolerated, whereas in artificial
teeth, the effect involves all of the teeth on the
bases and its traumatic

• Incising with the natural teeth does not
affect the posterior teeth whereas incising
with artificial teeth affects all of the teeth on
the base.
• In natural teeth, the second molar is the favored
area for masticating hard foods, owing to more
favorable leverage and power, heavy pressures
of mastication in the second molar region with
artificial dentition will tilt the base.

• In natural teeth, bilateral balance is rarely
found, and if present it is considered
balancing side interference. In artificial
teeth bilateral balance is generally
considered necessary for base stability.
• In natural teeth, prematurities are avoided due
to neuromuscular system control, in artificial
occlusion any prematurity causes instability
due to lack of feedback.

• An occlusion has to be designed to function
the compromised situation of the edentulous
mouth.

REQUIREMENTS OF COMPLETE
DENTURE:- (WINKLER)
• Stability of occlusion at centric relation
position and in an area forward and lateral
to it.
• Balanced occlusal contacts bilaterally for
eccentric contacts.
• Unlocking the cusps mesiodistally to allow for
gradual but inevitable settling of the bases due
to tissue deformation and bone resorption.

• Control of horizontal force by buccolingual
cusp height reduction according to residual
ridge resistance form and interarch
distance.
• Functional lever balance by favorable tooth
to ridge crest position.
• Cutting, penetrating and shearing efficiency
of occlusal surfaces.

• Anterior incisal clearance during
posterior masticatory function.
• Minimum occlusal contact areas for
reduced pressure in comminuting food..
• Sharp ridges or cusps and generous sluice
ways to shear and shred food with the
minimum of force necessary.

These requirements can be applied if the
occlusion is divided into 3 distinct units
• Incising,
• Working, and
• Balancing.

REQUIRMENTS FOR INCISING UNITS
• These units should be sharp in order to cut
efficiently.
• They should not contact during mastication.
• They should have as flat incisal guidance as
possible considering esthetics and phonetics.

• They should have horizontal overlap to
allow for base settling without
interference.
• They should contact only during protrusive
incising function.

REQUIREMENTS FOR WORKING
OCCLUSAL UNITS
• They should be efficient in cutting and
grinding.
• They should have decreased
buccolingual width to minimize the work
force directed to the denture foundation.

• They should function as a group with
simultaneous harmonious contacts at the end
of the chewing cycle and during eccentric
excursions.
• They should be over the ridge crest in the
mastication area for lever balance.

• They should have a surface to receive and
transmit force of occlusion vertically.
• They should center the workload near
anteroposterior center of the denture.
• They should present a plane of occlusion as
parallel possible to the mean foundation plane.

REQUIREMENTS FOR BALANCING
UNITS: -
• They should contact on the second molars
when the incision units contact in function.
• They should contact at the end of the
chewing cycle when the working units
contact.
• They should have smooth gliding contacts for
lateral and protrusive excursions. www.indiandentalacademy.com

SEARS AXIOMS FOR ARTIFICIAL
OCCLUSION (1952)
• The smaller the area of occlusal surface
acting on food, smaller will be the
crushing force on food transmitted to the
supporting structures.
• Vertical force applied to an inclined occlusal
surface causes non-vertical force on the
denture base. www.indiandentalacademy.com

• Vertical force applied to a denture base
supported by yielding tissue causes the
base to teeter when the force is not
centered on the base.
• Vertical force applied outside (lateral) to the
ridge crest creates tipping forces on the base.
• Vertical force applied to an inclined
supporting tissue causes non-vertical
force on the denture base.

It is the responsibility of the dentist to control
these forces in order to enhance
• Function,
• Stability and
• Comfort for the patients.

FORCES OF MASTICATION: -
• Mastication of food with natural teeth is
usually found to be 5 - 175lb.
• According to various studies
masticatory force in Complete denture-
Molar and Bicuspid region-22-24 lb,
Incisor region-9 lb

• Gibbs- 11.7 lb (10-15% of natural
dentition)
• Sheppard- 26 lb
The decreasing order of force of
mastication in CD is
2nd
premolar> 1st
molar> 1st
premolar.

PENETRATION OF BOLUS
• Carnivorous –have sharp incisors with steep cusps
shows vertical movement of mandible.
• Herbivorous- has flat crushing type of posteriors
with predominant horizontal movements.
• Omnivorous-
In young age – have more of carnivorous dentition
features.
In older age – have more of herbivorous dentition
features. www.indiandentalacademy.com

• Mehringer – studied force needed for food
penetration. He found that 20.2 lb is needed
for both cusped and non-cusp teeth. So in
patients with good ridges which can tolerate
20 lb the type of teeth to be used in not
critical.
Cusped teeth creates less vertical force
but increased horizontal force leading to
decreased stability of denture. Whereas,
non-cusped teeth have high vertical force
but low horizontal force.

• Researchers has shown no one type of teeth
to be best for all variable complete denture
patients
• A combination of cusped teeth on one arch
& flat teeth on the other is one of the
possible solution

PLANNING OF
OCCLUSION IN COMPLETE DENTURE
• Various authors published articles on
choosing ideal occlusion but they are not
scientifically based.
• International prosthodontic workshop
(1972): examined available scientific
evidence and to separate fact from
ancedotal comments concerning occlusion.
They concluded thatwww.indiandentalacademy.com

• Choice and arrangement of posterior
teeth is being done empirically with no
adequate scientific evidence. Available
research fails to identify a superior teeth
form /arrangement, so it is advised to
use least complicated approach that
fulfills the requirements of the patients.

Determining the least complicated
approach:-
The basic steps used are
• Philosophy of occlusion (satisfy patients
needs)
• Concept of occlusion (manner of teeth
contact)
• Selection of occlusal scheme.

Philosophy of occlusion:
• The occlusion selected should be
comfortable, functional, esthetically
pleasing.
• The following observations should be
kept in mind to attain this goal:

Tooth Contact Should Occur at Jaw Position
That Demonstrated Reproducibility-
• Centric relation should coincide with centric
occlusion for maximum stability and even
distribution of forces.
• Habits, muscle splinting, pain and discomfort
limit the accurate recording of Centric relation
, so adequate care should be taken while
recording Centric relation .

Degree of Incisal Guidance Established
Through Positioning of Maxillary and
Mandibular Anterior Teeth.
• High incisal guidance need steep posterior
cusps.
• Low incisal guidance need moderate cusp
angulations with
0.5 –1mm vertical overlap,
1.0 - 2.0 mm of horizontal overlap.

Absence of Deflective Occlusal Contacts and a
Free Gliding Articulation Between Opposing
Maxillary, Mandibular Anterior and Posterior
Teeth During Jaw Movements.
• Deflective contacts cause denture base
movement, irritation & inflammation to
supporting tissue.
• To prevent this, suitable type of occlusion
should be selected – balanced , monoplane ,
lingualized. www.indiandentalacademy.com

• A free gliding movement is of paramount
importance.
• So a freedom must be established by
occlusal reshaping procedure.

Selection and Arrangement of Tooth Forms /Molds
Such That Their Occlusal Surfaces Permit Occlusal
Reshaping to Achieve Freedom in Movements and
an Absence of Deflection.
• There should be adequate cusp height for
occlusal reshaping .
• Anatomical teeth satisfy this requirement.
However it also depends on the concept of
occlusion.

Positioning Anterior and Posterior Teeth to
Provide Naturalness in Appearance.
• The forms & contours of the most anterior
teeth have been designed with naturalness
in mind. But not in case of posteriors.
• So anterior teeth should be critically
selected.

Harold. r. ortmal (1971):- described
the 3 basic schemes of posterior
occlusion
• Spherical scheme- uses anatomic teeth in
balance occlusion and lingualized
occlusion.
• Flat occlusal scheme- non-anatomic
teeth are used. Balance occlusion does not
exist unless compensating curve, balancingwww.indiandentalacademy.com

• Reverse curve –given by Dr. Max
pleasure. Modified the lower posterior
teeth occlusal surface to a reverse curve
by tilting the tooth bucally, this did not
provide balancing contact.
• Balancing is possible introducing a spherical
scheme set in the second molar area by raising
the buccal incline. This is called the “pleasure
curve”.

Concepts Of Occlusion: -
• This is the second step in planning of
occlusion for complete denture. There are
various publications describing different
concepts of occlusion.
• They all fall under 3 categories-
1. Balanced occlusion.
2. Nonbalanced / Monoplane occlusion.
3. Lingualized occlusion.

• But as overall various concepts of CD
occlusion are
      Balanced occlusion
      Lingualized occlusion
      Monoplane occlusion
      Organic occlusion
       Linear occlusion
    Physiologically generated occlusion
 Neutrocentric occlusion.

BALANCED OCCLUSION
• Balance articulation can be defined “the
bilateral simultaneous, anterior and posterior
occlusal contact of teeth in centric and eccentric
positions”.
• Balance articulation is needed for stability and
comfort of complete denture.

• Hanau described the interdependence
of the 5 articulation factors and named
it “articulation quint”.

• Bonwill (1864) is known as the father of
anatomic /balanced 3 point contact occlusion.
It is mainly derived from various theories of
occlusion. Our modern concepts of balanced
occlusion are derived from geometrical
theories of Gysi.
• It is the ideal occlusal concept of complete
denture, but never exist in natural dentition.

• Trapazzano (1963): - reviewed Hanau’s five
factors and decided only 3 factors were
actually concerned in obtaining balanced
occlusion. He eliminated need for
compensating curve and occlusal plane,
called triad of occlusion.
• Boucher in (1963): - disagreed with Trapazzono
and felt that there was need for a compensating
curve. He also stated that the occlusal plane
should be included only in its correct anatomic
position.

• However Hanau’s five laws are found most
acceptable.

Advantages:-
• Increase stability of denture attained by
occlusal lever balance.
• Provides a harmonious relation with
surrounding stomatognathic system.

Disadvantages: -
• It may tend to encourage lateral and
protrusive grinding habits.
• A semi adjustable or fully adjustable
articulator is required.

DIFFERENT TYPE OF BALANCED OCCLUSAL
SCHEMES DESCRIBED BY VARIOUS AUTHORS:
• 1909 definite cusp form was released
• 1914 Gysi used 330
-cusp form of teeth.
Cusp contact bilaterally to enhance the
stability of dentures but show deflective
contacts in extreme lateral position.

French (1954) –decreased occlusal table
width of lower posterior, while maintaining
the balanced concept. He developed a
curved plane to attain lateral balance by
using minimum lingual inclines of maxillary
posteriors.
• (50
for 1st
premolar)
• (100
for 2nd
premolars)
• (150
for  1st
&  2nd
molars )

• Sears (1922) used channel type posterior
teeth. He used modified nonanatomic
teeth to attain balanced occlusion by
having curved occlusal plane
anteroposteriorly and laterally and a 2nd
molar ramp.
• Pleasure introduced Posterior reverse lateral
curvature except for the 2nd
molar which is set
with customary wilson’s curve to provide
balanced occlusion. www.indiandentalacademy.com

TYPES OF BALANCE
Unilateral Lever Balance
• It is present when there is equilibrium of the base
on its supporting structures when a bolus of food
is interposed between the teeth on one side and a
space exist between teeth on opposite side.

Equilibrium can be achieved-
• By placing teeth on the ridge.
• Selecting teeth with narrow buccolingual
width.
• Teeth placed close to ridge.
• Wide area of coverage of denture base.

Unilateral Occlusal Balance
• It is present when the occlusal surface of teeth
on a one side articulate simultaneously as a
group with a smooth uninterrupted glide.

Bilateral Occlusal Balance
• It is present when there is equilibrium on
both sides due to simultaneous contact of
teeth in centric & eccentric movements.
• it requires a minimum of 3 point contact for
establishing a plane of equilibrium.
• It depends on the Hanau’s quint.

Protrusive Occlusal Balance
 It is present when mandible moves forward
& contacts are smooth & simultaneous on
right, left posterior and anterior teeth.

FACTORS OF PROTRUSIVE BALANCE
• Inclination of the condylar path.
• Inclination of the incisal guidance chosen for
the patient.
• Inclination of the plane of occlusion set to
physiologic factors.

• The compensating curve set to
harmonize condylar guidance &
incisal guidance.
• The control of cusp heights and tooth
inclination of the posterior teeth.

FACTORS OF LATERAL BALANCE
• The inclination of the condylar path on the
balancing side.
• The inclination of the incisal guidance and
cuspid lift
• The inclination of the plane of occlusion on
the balancing side and working side.

• The compensating curve on the balancing
side and working side.
• The buccal cusp heights or inclination of
the teeth on the balancing side.
• The lingual cusp heights or inclination on
the working side.
• The Bennett side shift on the working side.

Factors That Affect Occlusal Balance
 Condylar guidance
 Incisal guidance
 Inclination of the occlusal plane
 The compensating curve
 Cusp height and inclination

Condylar guidance
It is the path of condyles traversing the
contours of the glenoid fossa.
It is one of the end controlling factors & it
is independent of tooth contact.

The condylar path is determined on the
patient by a protrusive record and set on the
instrument.
It acts as a posterior control factor.

Incisal guidance
 It is the influence of the contacting surfaces
of the mandibular and maxillary anterior teeth
on mandibular movements.
It is expressed in degrees of angulation from
the horizontal by a line drawn in the sagittal
plane between the incisal edges of the
maxillary & mandibular incisors when closed
in centric occlusionwww.indiandentalacademy.com

 Dentist can set it with accordance to
esthetics and phonetics.
 If the incisal guidance is steep it calls for
steep cusps , steep occlusal plane or a steep
compensating curve to effect an occlusal
balance.

For complete dentures the incisal guidance
should be as flat as esthetics and phonetics
will permit.
 When the arrangement of the anterior teeth
necessitates a vertical overlap, a
compensating horizontal overlap should be
set to prevent dominant incisal guidance from
upsetting the occlusal balance on the
posterior teeth.

• Incisal guidance should never exceed the
condylar guidance. It is the anterior
controlling factor.
• These 2 factors determine the movements of the
articulator.
• In order to achieve balance, the other 3
balancing factors are arranged to correspond to
these articulator movements.

Inclination of the occlusal plane
 Plane of orientation is established in the
anterior by the height of the lower cuspid
which coincides with the commissure of the
mouth and in the posterior by the height of the
retromolar pad. Its position can be altered
only slightly.

The compensating curve
• It is one of the most important factors in
establishing a balance occlusion. The
compensating curves eliminate Christensen’s
phenomenon to achieve balance.
• It is determined by the inclination of the
posterior teeth and their vertical relationship to
the occlusal plane so that the occlusal surface
results in a curve that is in harmony with the
movement of the mandible. www.indiandentalacademy.com

• The anteroposterior curvature of the
occlusal plane is desired to eliminate
protrusive disclusion of the posterior teeth
by the combination of anterior guidance and
condylar guidance.

• Mediolateral curve: it results from the
inward inclination of the lower posterior
teeth, making the lingual cusps lower than
the buccal cusps on the mandibular arch
and buccal cusps higher than the lingual
cusps on the maxillary arch.
• Aligning the teeth according to the above,
produces the greatest resistance to
masticatory forces.www.indiandentalacademy.com

• The inward inclination of the lower occlusal table
is designed for direct access from the lingual
aspect with no blockage by lingual cusps.
• The outward inclination of upper occlusal table
provides access from the buccal aspect for the
food to be tossed directly onto the occlusal table
by the buccinator muscle.

• When the curve of Wilson is made too flat,
ease of masticatory function may be impaired,
because of increased activity required to get
the food onto the occlusal table.

• A steep condylar path requires a steep
compensating curve for occlusal balance.
A less compensating curve would result in
a steeper incisal guidance, which would
cause loss of molar balancing contacts.

Cusp height and inclination
 These are important determinants, they
modify the effect of the plane of occlusion
and the compensating curve.
Mesiodistal cusp heights that interdigitate
lock the occlusion thus settling of bases
cannot take place
To prevent this, mesiodistal cusp heights
should be eliminated, only buccolingual
inclines need to considered for balanced
occlusion.

• All the five factors of balance interact with
each other.
• The dentist can control only four of the 5
factors, since the condylar path is fixed by
the patient. Incisal guidance and plane of
occlusion can be altered only slightly.
• The important working factors for the dentist
to manipulate are the compensating curve
and the inclination of cusps on the occlusal
surfaces of the teeth.

Contacts in Balanced Articulation
Working side:- The mandibular buccal cusp
ridges make articular contact with the
maxillary buccal cusp ridges as the
mandibular lingual cusp ridges are making
contact with the maxillary lingual cusp
ridges.

• Balancing side:- The mandibular buccal
cusps and ridge, contacts maxillary lingual
cusps and ridge.

• Protrusion:- Incisal edges of the mandibular
anterior teeth contact with the lingual surfaces
of the maxillary anterior teeth. The
mesiobuccal and lingual cusp ridges of the
mandibular teeth contact the distobuccal and
lingual cusp ridges of the maxillary teeth.

Balance in non-anatomic teeth
• Can be accomplished in one of 2 ways.
• One can either set the teeth in a
compensating curve as is done in anatomic
forms, or one can set the teeth in a flat plane,
and utilize a balancing ramp just distal the 2nd
molar. This ramp is adjusted so that the upper
2nd
molar will contact it in eccentric
movements and thus provide three point
contact.

• Pleasure (1937)- Balancing is possible
introducing a spherical scheme set in the
second molar area by raising the buccal
incline. This is called the “pleasure curve”.

SELECTIVE GRINDING: -
The errors in occlusion seen in completed
denture may result from
• I) Undetected error in jaw relation.
• II) Errors in mounting casts.
• III) Differences due to processing errors and
• IV) Changes in supporting structures

These are corrected by selective grinding.
• A clinical and lab remount is done. Errors
are detected by a articulating paper and
areas ground
• Errors in centric occlusion are corrected
first and then errors in lateral movements.
In centric , if the opposing functional cusp
contact, deepen the fossa.

• In lateral movements, BULL’S law is
followed i.e. only buccal cusps of the
maxillary teeth and the lingual cusps of
the mandibular teeth on the working
side are reduced.
• On the balancing side, lower buccal
cusp triangular ridge reduce.
• In protrusive movements distal inclines
of buccal upper cusp ridges and mesial
inclines of lingual lower cusps ridges are
relieved.

LINGUALIZED OCCLUSION
• It was originally given by Alfred Gysi
(1927) and Payne in 1941 familiarized it.
Pound and Murrel (1973) also advocated this
concept of occlusion.

• It is an attempt to maintain the esthetic and
food penetration advantages of the anatomic
form while maintaining the mechanical
freedom of the non-anatomic room.
• This concept utilizes anatomic teeth for the
maxillary denture and modified non-anatomic
or semi-anatomic teeth for the mandibular
denture. So, maxillary lingual cusp of
posterior teeth contact with mandibular teeth
in all centric and eccentric movements.

Indications:-
• In patients with severe ridge resorption,
which need non-anatomic teeth and
patient, desires on increased esthetics
and efficiency of denture.
• Class II jaw relation
• Highly displaceable tissue

Advantages:-
• Advantages of both anatomic and
nonanatomic teeth are made use of.
• Cusp form- increases esthetics.
• Good chewing ability.
• Bilateral balance
• Vertical forces are centralized on mandibular
teeth.

Principles of Lingualized Occlusion: -
• Maxillary teeth- anatomic teeth (30-330
)
with prominent lingual cusps.
• Mandibular teeth- non-anatomic with
narrow occlusal table. They may be
modified by selective grinding to create
smooth central fossa with concavity.

• Maxillary lingual cusp should contact
mandibular teeth in Centric occlusion,
maxillary buccal cusps are trimmed to
decrease interference.
• Balancing and working contacts should occur
only on upper lingual cusp with in 2-3 mm
excursive movements.

• Lingualized occlusion with cutter bars: use
metal blade teeth for maxillary denture and
flat nonanatomic mandibular porcelain
teeth.

Nonbalanced Lingualized Occlusion:
Indications: -
• Severely resorbed ridges/ flabby
ridges.
• Poor oral dexterity
• Who are not able to adjust to intricate
occlusal patterns.

• Patients who show poor accuracy of oral
records (jaw relation)
• Patients who do not accept monoplane
occlusion for esthetic reasons.

Features: -
• Maxillary posterior teeth should be anatomic
teeth with large, blunt lingual cusp.
• Mandibular posterior teeth with 00
teeth and
large marginal ridge areas and very shallow
grooves and sluice ways.

• Mandibular posterior teeth are arranged with
all central fossa in same line to establish the
occlusal plane.
• Maxillary teeth are arranged, buccal cusps
raised (1mm) and lingual cusps set on central
fossa.

• Clough et al (1983): - compared efficiency of
lingualized occlusion and monoplane
occlusion in complete dentures. Two sets of
dentures, one with lingualized occlusion and
the other with monoplane occlusion, were
made for each of 30 edentulous patients. 67%
of patients preferred lingualized occlusion
done to improved masticatory abilities,
comfort, and esthetics.

• Myerson lingualized integration (MIL)-is a
new type of tooth mold designed
specifically for concept of lingualized
articulation.

Advantages
• It provides maximum intercuspation
• Absence of deflective occlusal contact
• Adequate cusp height for selective occlusal
reshaping and
• Natural pleasing appearance

Available in two posterior tooth molds.
1.Controlled contact molds [CC]
2. Maximum contact molds [MC]

Controlled contact molds [CC]
• Is used for the patients where uncertainty
exists in registration & reproducibility of
centric relation.
• It provides for greater freedom of movement
around maximum intercuspation.

Maximum contact molds [MC]
• Is used for the patients where muscle control is
not a problem & jaw relations records are easily
repeated
• It is more anatomical in appearance

• More exacting occlusion is attained in
maximum intercuspation
• Bilateral balance can be achieved over a
great range of movement

MONOPLANE OCCLUSION
• It is a type of nonbalanced occlusion
where posterior teeth have masticatory
surfaces that lack any cusp height.

Advantages: -
• More adaptable to class II and III
malocclusions.
• Used more easily when variations in
the width of upper and lower jaws
indicate a cross bite set-up.
• 00
teeth provide sense of freedom in
mandibular movement.www.indiandentalacademy.com

• Eliminate horizontal forces to alveolar
ridge
• 00
teeth –occlude in more than one
position. Centric relation is not that
critical.

• It is simple, less time-consuming
technique and efficient for longer
duration.
• They accommodate better, to inevitable
negative changes in ridge height that
occurs with aging.

Requirements: -
• 00
teeth
• Articulator-a simple articulator that can
maintain vertical dimension, posses incisal
guide pin & do not need any complex
movements.

Features: -
• Anterior teeth have no overlap vertically
• Horizontal Overlap depends on jaw
relationship- 2,12,0 mm for class I, II, III
respectively.
• Maxillary posterior teeth are arranged 1st
,
after occlusal plane is determined.

• It should provide a occlusal plane that
parallels the mean denture base.
• There should be no contact between the
maxillary and mandibular anterior teeth. in
centric occlusion.
• Lower posteriors are arranged so that the
flat lingual cusp of maxillary tooth
contacts the central groove area of the flat
mandibular posterior.www.indiandentalacademy.com

• Anteroposterior position of upper & lower
teeth is not critical
• The posterior limit of the teeth is the point
at which the mandibular ridge begins to
curve upwards toward the retromolar pad

PHYSIOLOGICALLY GENERATED
OCCLUSION
• Mehringer J E(1973) developed this
occlusion to harmonize complete denture
occlusion neuromuscular system and Right
and Left TMJ.
• It is mainly indicated for patients having
adequate foundation with stable record bases.
And good neuromuscular control & can give
functional movements consistently.

Advantages
• It is comfortable to patient as it is built
physiologically, and swallowing and
masticatory movements are taken into
consideration.

Disadvantages
• It is time consuming and has no
scientific evidence of its efficiency in
attaining the goal.

Procedure: -
• The complete denture construction is
proceeded till jaw relations and then try-in and
processing of only maxillary denture is done.
After it is polished, a 200
conical disc is
attached to the palatal region of maxillary
teeth. The lower denture base is attached with
fabrication rim with plaster (1/3 chalk and 2/3
plaster) and attaching central bearing device.

• Patient is asked to make chewing and
swallowing movements, which creates
functionally generated paths. Then apply
separating medium to obtain maxillary
stone cast of generated paths.
• Then lower teeth are arranged
according to maxillary cast of generated
path. 2-point contact on working side is
eliminated and converted to one point
contact, this increases stability and transmit
forces on lingual cusps only.

NEUTROCENTRIC OCCLUSION
• It mainly uses the concept of arranging
teeth on a plane (flat) parallel with bony
support.
• It is independent of horizontal condylar
guidance and has no compensating curves.
It eliminates anteroposterior and
mediolateral inclination of teeth, which
directs force of occlusion on posterior teeth.
There are no balancing contacts.www.indiandentalacademy.com

The five factors involved in the relation of
the form of the teeth to the denture
foundation are:
• Position,
• Proportion,
• Pitch,
• Form, and
• Number.

Position: (centralized) Position teeth in as
centre as possible in reference to the
foundation as the tongue will allow in order
to provide greater stability for the denture.
Proportion: (reduced) A reduction of 40%
in width is possible without serious
diminution of the food table. A reduction in
width is necessary to establish
centralization without encroachment on
tongue space, and reduction of frictional
force. www.indiandentalacademy.com

Pitch: Parallel the pitch of the occlusal
plane with that of the maxillary and
mandibular base planes. The occlusal plane
is parallel to the base plane and the teeth are
set to a flat plane rather than a sphere.
Form: (cuspless tooth form) No cusp.
Number: (reduced) Eliminate the second
molar.

LINEAR OCCLUSION
• “ The occlusal arrangement of artificial teeth, as
viewed in the horizontal plane, where in the
masticatory surfaces of the mandibular posterior
artificial teeth have a straight, long, narrow
occlusal form resembling that of a line, usually
articulating with opposing monoplane teeth” –
FRUSH (1996)

• Teeth are arranged on a flat plane, which
extend from tip of maxillary incisors to the
2/3rd
of retromolar papilla.
• The anterior vertical overlap is absent
leading to non-interception in eccentric
movements.

• The posterior teeth used are non-
anatomic with mandibular blade form of
teeth. They exhibit bilateral fulcrum of
protrusive stability

• This type of occlusion uses straight line of
points / knife edge contacts on artificial
teeth in one arch against flat non anatomic
teeth in opposing arch thereby decreasing
unfavorable forces and simplifying occlusal
adjustment.

The main advantages are –
• It decreases lateral forces component ,
• Decrease frictional resistance &
• No change in contact during eccentric
movements so direction of force is constant.

Different type of posterior teeth
combinations can be used: -
• Nonanatomic maxillary porcelain teeth
opposing mandibular porcelain linear
teeth.
• Nonanatomic maxillary plastic teeth
with mandibular linear plastic teeth.
• Nonanatomic maxillary plastic teethwww.indiandentalacademy.com

• Non anatomic maxillary porcelain teeth
with mandibular linear plastic teeth.
• Lower posterior teeth are arranged
with buccal cusp centered on crest of
ridge, and lingual cusp 0.5mm below
occlusal plane. Maxillary posterior teeth
have flat occlusal surface parallel to flat
horizontal plane. There is no anterior
teeth overlap.www.indiandentalacademy.com

ORGANIC OCCLUSION
• It is mutually protected occlusion in
which posterior teeth protect the
anterior in centric occlusion and anterior
teeth protect posterior teeth in eccentric
positions.
• If properly constructed and related this may
also be the best type of occlusion for
complete denture and removable partial
denture. www.indiandentalacademy.com

• The groove and ridge direction of
cusp is determined as a result of condylar
movement. Cusp fossa contact relation is
used with centric relation. It requires an
articulator capable of receiving and
reproducing pantograms in 3 planes.

METHODS OF STUDYING OCCLUSAL
CONTACT
• Articulating papers.
• Type writer ribbons
• Wax
• Liquid paint
• Powder aerosols

• T-scan system
(uses polyester film
substance 100µm
thick with a thin
conductive system)

Dental prescale –
• use pressure sensitive
sheets and occluzer a
computer to analyze
the contacts

• A thorough understanding of force
management in complete denture
through selecting and delivering a
correct occlusion scheme is important
for the long term success of denture.

Selecting the occlusal scheme
Posterior teeth are generally classified as
• Anatomical
• Nonanatomic
• Zero degree
• cuspless

Anatomical
• It was designed for the function of
mastication
• Their cusps were arranged so that they
shear & crush food when a reasonable
biting force is applied.
• Adequate grooves & escape channels were
positioned to assist in preparation of food
for swallowing

Advantages
• Ease in developing bilateral balanced
occlusion
• An excellent esthetic quality
• An excellent masticatory efficiency

Disadvantages
• Possible damage to the supporting tissues
due to deflective occlusal contacts
• When bone loss occurs mal-relation of the
opposing cusps directs the maxillary
denture forward & mandibular denture
backwards leading to discomfort &
irritation to soft tissues & potentially more
bone loss

Nonanatomic
• Its designed with out cusps to allow for
intercuspation anywhere along the occlusal
plane anteroposteriorly.

Advantages
• Versatility of use in class II & class III jaw
relation
• Closure of jaws in a broad contact area
• Creation of minimal horizontal pressures
• Easier maintenance of the complete
dentures
• Fabrication of the dentures with simple
techniques & articulators

Disadvantages
• Lack of esthetic quality
• Inability to penetrate food

Zero degree
• Have zero degree cuspal angles in relation
to the horizontal occlusal surface.
Cuspless teeth
• Were designed with out cuspal prominence

Type of tooth form related to type of residual ridge
Ridge type Interridge
distance
Ridge
relation
Posterior type
Prominent
firm
Close ideal Normal Anatomic 1
Prominent
firm
Average prognathus Anatomic 1
Average Average Orthognathus Anatomic 2/3
Average Close Orthognathus Anatomic 2/3

Ridge type Interridge
distance
Ridge
relation
Posterior type
Average Large Normal Anatomic 2
or Monoplane
Flat firm Large Normal Monoplane
Flat firm Excessive Prognathus Anatomic 2
or Monoplane
Flat flabby Excessive Orthognathus Monoplane or
Reverse curve

OCCLUSION IN SPECIAL
SITUATION’S
Single Complete Denture:-
• Many difficulties confront the dentist in
rehabilitating patients with this clinical
pattern. The dentist must be able to
develop a suitable occlusion. Within the
clinical limitation to maintain and
preserve the health of the remaining
tissues.

Robert w Bruce(1971):- discussed factors to
be considered in developing occlusion for
single complete denture
Planning of occlusion: -
 Examination of remaining teeth-
extruded / malposed teeth –extraction;
occlusal plane, cusp height.

Final occlusion should have plane 0f
occlusion with low cusp height.
Occlusal reshaping done using resin
template
Mandibular single complete denture is
usually contraindicated due to
increased forces on mandibular ridge
leading to increased resorption and
chronic sore mouth.

Final occlusion: -
• Should Direct forces vertically,
Posteriorly, bilaterally balanced.
• Posterior teeth should not extend
beyond 1st
molar.
• Cast gold occlusal surface (plates) with
broad occlusal table.
• The presence of natural teeth in the
opposing arch increases the force on
the single complete denture.

• The occlusal form of the remaining
natural teeth, dictate the occlusal form
of the denture.
• Malposed, tipped or supra-erupted
teeth make it difficult to achieve a
harmonious balance occlusion. Several
techniques have been described
whereby the necessary tooth
modifications are determined prior to
denture construction.

Swenson in 1964
• Described a method where the teeth are set
and any interference with the placement of
the denture teeth are adjusted on the cast
and area marked, the natural teeth are then
modified using the marked diagnostic cast
as a guide. After the occlusal modifications
have been completed now diagnostic cast of
the lower arch is made and mounted and the
denture teeth & reset.

• Yurkstas in 1968 described a
method where the teeth to be adjusted
on the occlusal surfaces are identified
with use of a metal u shaped occlusal
template.
• Bruce in 1971 has described the use
of a clear acrylic resin template.

• Many techniques have been
described explaining ways to achieve a
balanced occlusion for a single
complete denture.
1) Functional chew –in technique
2) Articulator equilibration techniques

Functional chew –in technique
• Stansbury in 1951: instructed patient to
perform eccentric chewing movements
on a compound rim which is trimmed
bucally & lingually into which carding
wax is added. Generated occlusion rims
is removed & stone is vibrated into the
wax path of the cusps.

• The denture teeth are first set to the lower
cast of the patients teeth. After the esthetics
have been approved at the try-in , the lower
cast is removed and the lower chew-in cast
record is secured to the articulator then
teeth are carefully ground to achieve a
bilateral balanced occlusion.

• Vig in 1964 described a similar
technique but he recommended the use
of a fin of resin placed into the central
grooves of the lower posterior teeth,
instead of compound.
• Sharry (1968) used a maxillary rim of
softened wax to obtain lateral and
protrusive chewing movements, generating
functional paths. This is continued until the
correct vertical dimension is established.

• Rudd (1973) has described a technique
similar to stansbury, but he used sheets
of medium hard pink base plate wax
instead of compound rim.

2) Articulator equilibration techniques: -
• If the denture bases lack stability or
the patient is physically unable to form
a chew-in record, the articulator
equilibration method is preferred.
• The upper cast is mounted on
articulator using a face-bow record and
the lower cast is related to the upper by
a centric record.

• A decision whether to articulate the
central fossa of the denture teeth to the
lower buccal cusps or to the lower
lingual cusps must be made.
• If the denture teeth appear to be placed
too far to the buccal when articulated
with the lower buccal cusps, they are
reset to oppose the lower lingual cusps
and if they are too far lingual, they are
reset to oppose the lower buccal cusps.

• Occasionally buccal cusps may be used
on some and the lingual cusp on other
teeth.
• Once the holding cusps have been
selected, the incline of the remaining
cusps are reduced. When lower buccal
cusps are selected for the holding
cusps, the lingual cusps are reduced,
and balance is achieved.

• Lateral balance can be achieved by
selectively grinding the interfering
buccal and lingual cuspal inclines of the
upper teeth.
• If non-anatomic teeth are used, then a
free articulation is usually obtained in
lateral excursive movements.

Resorbed Ridges: -
• The cuspal morphology of
posterior teeth is dictated by the shape
and prominence of the ridge and its
ability to withstand lateral forces. In the
lower ridge the primary concern is
during grinding of teeth. It is advisable
to use non-anatomic teeth for severely
resorbed ridges.

Occlusal consideration’s in severely
resorbed ridges:-
• The occlusal scheme should mainly
aim at decreasing the amount of load
applied on the residual ridge and
mucosa.
• Place teeth in neutral zone to decrease
lateral stress on bone.

• Wide area of impression surface.
• Area of occlusal table should be small

• Morphology of occlusal table
depend on patients chewing
/masticatory habits
-Choppers (vertical mastication)-
semi anatomic /non-anatomic teeth.
-Grinder (horizontal mastication)-
nonanatomic teeth.

• Occlusal balance
-Choppers- contact (or) balanced
occlusion in RCP only.
-Grinders- (mixture of vertical, lateral
and protrusive) essentially need
bilateral balanced occlusion in all
eccentric and centric movements.
• Removal of disruptive occlusal
contacts.

• Simieon baron(1997) (not evidence
based) described alternative technique to
tooth arrangement for completely
resorbed mandibular ridge.
• Lower anterior teeth arranged edge-edge/
protrusive to maxillary anteriors.
• On protrusion no anterior contact and
downward pressure on denture keeping it
stable. The author recommends use of
220
teeth and use posterior bilateral balanced
occlusion. www.indiandentalacademy.com

Maxillofacial prosthesis replacing
maxillary and mandibular defects:
-
• Occlusal schemes for such
patients has to be carefully selected as
they determine the stability and
retention of prosthesis to some extent.
Usually non anatomic posterior teeth
preferred with lateral deflective
contacts eliminated. It is better to use
neutral zone for orienting posterior

• Mandibular defects: -
• In cases of complete resection of mandible use
of functionally generated path of technique can
be used to get desired occlusion.
• Done using a black modeling compound wax.
• It is not applicable for all complex cases.

• It is applicable when reconstructed
mandible show limited lateral and
protrusive excursive movement.
• In case of limited resections of alveolar
bone, monoplane posterior teeth in neutral
zone may be helpful.

Combination Syndrome:-
• Saunders(1976) described the changes
observed when a maxillary complete
denture opposes remaining lower anterior
teeth with a RPD in the posterior segment.
The symptoms are summed as
“combination syndrome”

• The 5-potential changes referred as
combination syndrome are
• Papillary hyperplasia
• Bone resorption in anterior region
• Extrusion of teeth
• Mandibular bone resorption in posterior
region
• Downward growth of maxillary tuberosity.

• The 6- changes seen in the prosthesis:-
Decreased VDO
Periodontal changes in reaming natural
teeth
Anterior mandibular repositioning
Occlusal plane discrepancy
Poor prosthetic adaptation
Epulis fissuratum

Occlusal considerations in
combination syndrome:-
• If the ridge in maxillary and mandibular
posterior region is resorbed and poor.
The most important requirement is the
occlusal scheme which will stop further
progress of pathologic changes.

• No contact in incisors in centric and
minimal contact in eccentric
movements.
• Balanced occlusion to be used with
proper cusp angulations relating to
condylar and incisal guidance

William s. jameson (2001): -
• Described the use of linear occlusion to treat
a patient with combination syndrome.
• The author eliminated the anterior overlap
and prevents contact of incisors during
function, the teeth were arranged using
monoplane from maxillary central incisors to
tip of retromolar pad.

Occlusion In Implant Supported
Complete Denture: -
• Implants have no periodontal ligament
so the selected occlusal scheme should
provide forces directed more vertical
than horizontal. Less amount of lateral
forces should be present.

• For fully bone anchored complete
denture mutually protected occlusion is
recommended.
• Balanced occlusion creates lot of lateral
forces component leading to implant
failure. So it is contraindicated in fully
bone anchored prosthesis.
• In case of implant-supported over-
denture balanced occlusion is
recommended.www.indiandentalacademy.com

Abnormal Jaw Relations: -
Class II jaw relation- the
recommended occlusion is balanced
lingualized occlusion and monoplane
occlusion.
The main problems encountered are:-
• Increased anterior overlap
• Abnormal speech patterns
• Difficulty in achieving desired phonetic
ability. www.indiandentalacademy.com

• Increased bone loss in maxillary
anterior region- increased loss of VDO.
• They often hold mandible in forward
position- difficulty in recording centric
relation.
• It is advisable to use shallow incisal
guidance 200
. Incisal guidance cannot
be reduce to 00
for esthetic and phonetic
reasons. If decided to have 00
incisal
guidance non-balanced lingualized
occlusion should be used.

• Canine misalignment cause posterior
arch length discrepancy. So select
narrow mandibular anterior should be
used or drop mandibular 1s t
premolar
• Mandibular posteriors are arranged before
maxillary using common guidelines.
Excessive grinding is needed to eliminate
mesiodistal unlocking due to increase
anteroposterior movement.

Class III relation:- usually
monoplane occlusion is preferred. But
balanced lingualized occlusion can be
used.
The main problems encountered are: -
• Mandibular arch larger than mandibular
arch.
• Mandibular anteriors are in edge-edge
relation www.indiandentalacademy.com

• Canine misalignment –compensated by
using wider and shorter anterior teeth
mold, adding diastemas distal to
canine.
• Posterior arch discrepancy advised to
drop a maxillary 1st
premolar.

• There exists a posterior cross arch width
disparity with mandibular arch wider than
maxillary arch. So a cross bite relation can
be used.
• A completely balanced but buccalized form
of occlusion can be used. Excursive balance
is not a problem as the range of horizontal
mandibular movement is less.

CONCLUSION:-
• “Dentures are mechanical devices
and are subjected to the principle of
physics (mechanics), that is the
inclined plane and the lever. The
forces will operate whether or not we
recognize them, rather than let them
operate uncontrolled, it is the
responsibility of the dentist to control
them in order to enhance function,
stability and comfort”
-Sheldonwww.indiandentalacademy.com

BIBLIOGRAPHY
Prosthodontic treatment for edentulous
patients.[11th
edition]
-Boucher
Syllabus of Complete Denture - Heartwell
Essentials of complete denture
- Sheldon Winkler

Text book of complete dentures.
-Swenson.
The Glossary of Prosthodontic Terms 8th
Edition
- The Academy of Prosthodontics

• Jones, P.M. The monoplane occlusion for
complete dentures. JADA 85:94-100, 1972.
• Brudvik, J. S. and Wormley, J. H. A method of
developing monoplane occlusion. J Prosthet Dent
19:573-580, 1968.
• Nimmo,A. DDS and Kratochvil,J. DDS Balancing
Ramps in Complete Denture Occlusion. J
Prosthet Dent 85 53:431-433
• DeVan, M.M. Concept of Neutro-centric
occlusion. JADA 48:165-169, 1954.

• Clough, H. E., et al. A comparison of lingualized
occlusion and monoplane occlusion in complete
dentures. J Prosthet Dent 50:176-179, 1983.
• Becke, C. J., Swoope, C. C. and Gockes, A. D.
Lingualized occlusion for removable prosthodontics.
J Prosthet Dent 38:601-608, 1977.
• Hardy, I.R. and Passamonti, G.A. Method of
arranging artificial teeth for class II jaw relations.
J. Prosthet Dent 13:606-610, 1963.
• Brudvik, J.S. and Wormly, J.H. A method of
developing monoplane occlusions. J Prosthet Dent
19:573-580, 1968.

• Wee.g.a et al “utilization of neutral zone
technique for a maxillofacial patient”. J
prosthodont 2000,9,2-7.
• Richard A. Williamson et al, “Maximizing
Mandibular Prosthesis Stability Utilizing Linear
Occlusion, Occlusal Plane Selection, and Centric
Recording”,JP 2004 vol 13(1).55-61
• Anna M et al,”The importance in occlusal balance
in control of complete dentures” quint int 98 vol
29, 6.

• Neutral zone approach for denture fabrication for
a partial glossectomy patient: a clinical report.
J Prosthet Dent. 2000 Oct;84(4):390-3.

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