Teeth arrangement for complete dentures/ orthodontics courses online

Teeth arrangement for
complete dentures
INDIAN DENTAL ACADEMY
Leader in continuing dental education
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Contents
 Introduction
 Principal factors governing positions of teeth
 Anatomic landmarks – in maxilla
in mandible
 Facial profile
 Anterior teeth arrangement
 Arch form
 Posterior teeth arrangement
 Compensating curves
 Ridge relations
 Atypical arrangement of teeth
-class 2 ridge relation
-class 3 ridge relation
 Teeth arrangement for balanced articulation
 Teeth arrangement for monolpane occlusion
 Teeth arrangement for lingualised occlusion
 teeth arrangement for esthetics.
 Review of literature
 References

 Esthetic tooth placement and physiological tooth
arrangement are biologically compatible and
desirable as end products of proper complete denture
construction.
 Proper placement of teeth should be functionally as
well as esthetically pleasing.

 The position of the maxillary anterior arch, and the
arrangement of the individual teeth make the most
crucial contribution to the appearance of the face.
 The teeth are not only an important component of
facial appeal, they give each face a unique identity,
just as eyes, nose, and skeletal proportions make
each face distinctive and easily recognised.

 The artificial tooth replacements can, and
should contribute to the distinction of each
patient's face, just as the natural teeth did,
and in the process go some way to restoring
the lost body image.
 The goal in setting artificial teeth is quite
simply to put them where the natural teeth
were (Bissasu, 1992).

 The setting of teeth is a combination of science and
art and one of the most abused sections of prosthetic
dentistry.
 It is very difficult to lay down exact rules for guidance
in this phase of prosthetic dentistry.
 Too often the emphasis is placed on occlusion as
being the only important factor in arrangement of
teeth.

Some of the common errors in arrangement of teeth include:
 Setting mandibular teeth too far forward to meet the maxillary
teeth
 Failure to make the cuspids the turning point of the arch
 Setting the mandibular first premolar buccal to the canines
 Setting maxillary posteriors over the ridge and then occluding
the mandibular teeth , bringing them too far to the lingual in the
molar region
 Failure to set the posterior teeth in a line of compromise
between the two ridges.

 The artificial teeth are attached to a movable base
resting on movable and displaceable living tissue,
which are subject to damage.
 They act as a unit , therefore, they must be
arranged to function as a unit.

Factors Governing the Positions of Teeth
The positions of the artificial teeth are influenced by
(1) the functions of the surrounding structures,
(2) the cellular structure of the basal seat tissues,
( 3) the anatomic limits, and
(4) the mechanical aspects.

 The five principal factors regarding the
arrangement of teeth are
group 1 1.antero posterior position of the arch
the arch as a unit
2.shape of the arch
3.orientation of the plane
group 2 1.individual inclinations for balance
individual positioning of the 2.individual positions for esthetics
teeth in the arch

The 4 principal factors that govern the positions of the teeth for
complete dentures are
(1) the horizontal relations to the residual ridges.
(2) the vertical positions of the occlusal surfaces and incisal
edges between the residual ridges.
(3) the esthetic requirements, and
(4) the inclinations for occlusion .

HORIZONTAL POSITIONS
 The antero posterior position of the arch should be
governed chiefly by the orbicularis oris and its
attaching muscles.
 These muscles control the expression and reflect the
personality and appearance of every person wearing
complete dentures.

The horizontal positions of teeth to residual ridges
involve placing the teeth anteroposteriorly and
mediolaterally
(1) to provide stability
(2) to direct forces of mastication to areas most
favorable for support,
(3) to support the lips and cheeks for esthetics, and
(4) to be compatible with the functions of the
surrounding structures

 Forces directed at right angles to the supporting
tissues are more stabilising than forces directed at an
inclined plane.
 Protrusive and lateral movements involving tooth
contacts result in forces directed toward inclined
planes and these forces are capable of dislodging the
dentures.

 The character of the mucosa and submucosa must
be considered when the teeth are positioned.
 The forces of mastication should not be directed to
tissue incapable of withstanding force.
 The differentiated submucosa in the distal two thirds
of the palate and in the retromolar pad are not
capable of bearing stress.
 The loosely attached submucosa in the vestibular
fornix provides a good denture seal area but should
not be subjected to the stresses of occlusion.

VERTICAL POSITIONS
 The arrangement of artificial teeth in the
correct vertical positions involves placing the
anterior and posterior teeth in an acceptible
position between the two residual ridges in a
vertical direction.

As in correct horizontal positioning, correct
vertical positioning of teeth should provide
1. Denture stability
2. Favorable forces
3. Support for lips and cheeks
4. Compatibility

Vertical positions of mandibular posterior teeth
Two anatomic guides to establish the vertical position of
the occlusal surfaces of the posterior teeth are
(1) The orifice of the duct of the parotid gland
(Stensen’s duct )
(2) the retromolar pad.

 The occlusal surface of the maxillary first
molar is approximately ¼ inch below the
orifice of the duct of the parotid gland.

 The occlusal surface of the last mandibular
natural molars is on a plane approximately at
the bottom of the upper third of the retromolar
pad.
 This vertical position is usually compatible
with the activities of the tongue and cheeks.

Vertical positions of maxillary anterior teeth
 Esthetics and phonetics are used to establish the
vertical position of the incisal edges of the maxillary
anterior teeth.
 The patient is instructed to say ‘ fifty five’ and the teeth
are adjusted until the incisal edges of the maxillary
incisors contact the vermilion border of the lower lip at
the junction of the moist and dry mucosa.

 The use of the ala tragus line is an
expediency and not a reliable indication for
the occlusal surfaces of the teeth.
 The plane is not used unless it coincides with
the other guiding factors.

 The occlusal plane is established using the
retromolar pad for the posterior and the
incisal edge or lower lip line for the anterior
points of reference.

Facial profile
 As a general rule, the labial faces of the maxillary
central incisors are parallel to the profile line of the
face.
 In the prognathous type, where the mandibular
incisors protrude, the incisal edges of the maxillary
teeth are farther out than the necks of the teeth.
 When the mandibular incisors are retruded, the
incisal edges of the maxillary teeth are toward the
lingual than the necks of the teeth.

Labial face of central incisor parallel with the profile line
of the face

 When the maxillary central incisor is inclined to be parallel with
the profile line of the face, the lateral incisor must be set at an
opposite angle to avoid a predominance of parallelism.
For example, in the retrusive case, when the maxillary
central incisors are out at the neck, the lateral incisors must
then be depressed at the neck in order to oppose the line that is
made by the labial faces of the central incisors.
 In the prognathous set up , the incisal edges of the maxillary
central incisors are to the labial. The maxillary lateral incisors in
this set up then are placed slightly out at the neck to oppose the
central labial face line.

Anatomic landmarks
 Beauty in nature arises from variations being in
harmony; without harmony, variations are abnormal
and, consequently, not beautiful. By using anatomic
reference, it is possible to place artificial teeth within
the bounds, or “averages,” of nature, and individual
esthetic and physiologic variations would be
permitted during the trial denture phase.

The anatomic landmarks most useful as guides for positioning artificial
teeth are:
in the maxilla
1) the maxillary labial vestibule,
(2) the incisive papilla,
(3) mid sagittal suture
(4) canine lines
(5) the maxillary tuberosity,
in the mandible
(1) the mandibular labial vestibule,
(2)the retromolar pad.

 The mid sagittal suture, incisive papilla and
labial frenum are guides to the median line.
 A line is drawn antero - posteriorly bisecting
these points and the line extending to the
margin of the cast.

 Maxillary labial vestibule
 The soft-tissue reflection of the maxillary vestibule from canine
to canine forms the denture border in that region.
 In most dentitions, the distance from the incisal edge of the
central incisors to the labial vestibule at a point immediately
lateral to the labial frenum is 22 mm.
 This measurement seldom varies by more than 1 mm except in
petite persons in whom it may be only 18 mm.
 The position is perfected and verified at the trial denture
appointment.

Incisive papilla as a guide
 The incisive papilla is a valuable guide to
anterior tooth placement because it has a
constant relationship to the natural central
incisors .
 The labial surfaces of the natural upper
central incisors are 8-10 mm in front of the
middle of the incisive papilla.

 Another reference is the distance between
the most anterior border of the incisive papilla
and the labial surface of the central incisors,
which varies from 5 mm for a square arch
form, to 6 mm for an ovoid arch, to 7 mm, for
one that tapers.

 In addition, the incisive
papilla is also related to
the canines and is
situated on the line
passing through the tips
of the canines in the
dentate person.

 If the artificial teeth are replaced in the natural tooth
position by referring to the incisive papilla, the molar
teeth will move forward and the tongue space will
become wider.

 If the anterior teeth are arranged on the incisive papilla, the lip
cannot be adequately supported and their position will also
affect the arrangement of the molar teeth.
 The artificial teeth will be arranged altogether posteriorly and the
tongue space will be greatly restricted.
 If the anterior teeth are placed in the position previously
occupied by the natural teeth by referring to the incisive papilla
as a landmark, the molar teeth will have an anterior shift
accordingly and approach the position of the natural teeth. Thus
the tongue space will become wider.

 The canine lines.
 The six maxillary anterior teeth occupy the space between the distal of
the right canine eminence and the distal of the left canine eminence.
 When the canine eminences are visible on the cast, a line coinciding
the posterior margin of the eminence coincides with the posterior
surface of the canine.
 This line is recorded on the margin of the cast.
 When the eminences are not visible, the points recorded at the corners
of the mouth using the mandibular occlusal rim are taken as reference.

 Maxillary tuberosity
 The maxillary tuberosity lies immediately posterior to
the maxillary second molar. This relationship could
be with the first or third molar instead of the second.
 This landmark is less reliable as atrophy increases,
but generally it is useful.

Diagram of the upper arch showing average distances from the palatal
gingival margins of the furthest horizontal extent of the denture flange in the
incisal (A), canine (B), premolar ( C) and molar (D) regions (the biometric
approach).
The line X - X passing through the posterior border of the incisive papilla can
be used as a guide to position the tips of the canines.www.indiandentalacademy.com

 Mandibular labial vestibule
 The relationship between the six mandibular anterior
teeth and the mandibular labial vestibule is similar to
the maxillary anterior tooth to vestibular relationship.
 The principal difference is in the distance from the
incisal edges to the labial vestibule which is
approximately 18 mm.
 When dentures are constructed, clinical verification is
essential.

 Retromolar pad

 The retromolar pad is the anatomic landmark used
most frequently as a reference for tooth placement
for it applies in three dimensions—vertically, laterally,
and anteroposteriorly.
 It guides the height of the occlusal plane.
 In a monoplane artificial-tooth arrangement, the
occlusal plane lies in the middle of the pad.

 Laterally, the retromolar pad guides the buccolingual
position of the posterior teeth.
 Pound states that the lingual cusps of the mandibular
posterior teeth lie within a triangle formed by the
buccal and lingual borders of the retromolar pad and
the mesial surface of the mandibular canine.
 Anteroposteriorly, no artificial teeth are placed
posterior to the anterior boundary of the pad.

 The mean measurements of preextraction
buccolingual breadth of the alveolar process
gives an approximate guide to the
breadth of the flange of complete upper
dentures and to pre-extraction lip and cheek
positions.

Anterior tooth arrangement
 Payne states, “set the teeth where they grew.”
 With this as a guide , it is possible to more closely
place the artificial tooth in approximately the position
that was in the patient’s natural dentition.

 In the upper anterior region, bone resorption following
extraction will occur upward and inward because of
the direction and inclination of the roots of the teeth
and alveolar process.
 In addition, the buccal alveolar bone is thinner than
that of the palatal side and thus bone resorption is
faster and greater labially. Consequently, the alveolar
crest will move posteriorly according to the resorption
of the alveolar bone.

 The alveolar crest of the upper anterior region will move posteriorly
according to the pattern of bone resorption. If this pattern is ignored and
the artificial teeth are placed on the crest of ridge, the lip support will be
inadequate.
 For the provision of adequate and appropriate support of the lip, the
artificial teeth must be placed in the positions occupied by the natural
teeth.

 Placing anterior teeth in harmony with functional
activity involves placing the teeth in an
anteroposterior and mediolateral position in harmony
with the action of the lips and the tongue.

If the upper lip is not properly supported, its shape wilL be concave, thus
the skin will lose its tension and wrinkles will occur, leading to
the”denture-caused” elderly appearance. This is a characteristic feature
of the denture wearing patient.
With a new denture having adequate upper lip support, the elderly
appearance is no longer obvious.www.indiandentalacademy.com

Overlap of the anterior teeth
The anteroposterior relationship of the upper and
lower anterior teeth, that is the horizontal overlap, is
automatically decided by the relation between the
upper and lower residual ridges.
 The upper and lower anterior teeth should not be in
contact in the centric occlusal position in any case.

 The incisal edges of the maxillary and mandibular
anterior teeth should have a 0.5-mm vertical overlap.
 A 1- to 2-mm horizontal overlap must exist between
the lingual surface of the maxillary anterior teeth and
the labial surface of the mandibular anterior teeth.
 Such an arrangement will create a low incisal
guidance, which is exactly what one should achieve
for the patient.

0.5 mm of vertical overlap and
1 to 2 mm of horizontal overlap
must exist between the
maxillary anterior teeth and
their mandibular antagonists to
achieve a low incisal guidance,
which is needed for the
anterior teeth to function in
harmony with most posterior
tooth forms.

The upper and lower anterior teeth should not be in contact in
the centric occlusal position.

 Settling of complete dentures occurs 1-2 weeks after insertion,
mainly due to the compression of the mucosa under the denture
base. So, if the anterior teeth are arranged in contact, following
the settling of the dentures, an impact between the opposing
anterior teeth and an upward thrust of the anterior region will
occur during occlusion, leading to an earlier loss of denture
retention.
 Even though the teeth were in contact in the natural
dentition, they should be arranged out of contact at least
just enough to compensate for the amount of settling after
insertion.

 In addition, due to the excess pressure exerted,
resorption of the alveolar ridge in the anterior region
will be increased and soft tissue hyperplasia, that is
so-called flabby gums, will occur in this region.
 The teeth should be arranged out of contact just
enough to compensate for the amount if settling
which occurs soon after insertion. By providing such
a horizontal overlap, the incisal guide inclination is
reduced and there will also be an improvement in the
stability of the complete denture.

 When determining the vertical level of the incisal edges of the
anterior teeth using the occlusion rim, it is generally adjusted so
that the upper anterior teeth are exposed about 1-2 mm below
the border of the upper lip with the mouth slightly opened.
 However, depending on the individual, the amount of upper
tooth showing varies. Therefore if this level is adhered to, the
entire occlusal plane will be affected causing it to be either too
high or low.

 In the lower anterior region, the lower anterior teeth
are covered by the lower lip and quite inferior to its
border.
 The incisal edges of the lower anterior teeth are
located at the level of the lower lip when the mouth is
slightly opened.
 Therefore, the lower lip is said to be a better guide for
the vertical orientation of the anterior teeth than the
upper lip.

a. b.
The central incisors are slightly visible and they look esthetically pleasing.
However, the lower anterior teeth are covered by the lower lip and quite inferior
to its border (a).
The occlusal plane is raised up so that the incisal edges of the lower anterior
teeth and the cusps of the lower first premolars are located at the level of the
lower lip when the mouth is slightly opened. Thus the balance between the upper
and lower denture is improved (b).

ARCH FORM
 In the absence of other more definite information, the arch form is
used as a guide for the initial arrangement of the teeth.
 The edentulous arch form bears a direct relation to the contour of
the face provided there has been no loss of bone due to disease, no
loss of bone due to the length of time the teeth have been missing,
and that the teeth were all removed at one time.
 The opposing arches do not always follow the same contour.

 Anterior and posterior teeth must vary in size and
form, therefore teeth must be selected from anterior
and posterior molds separately rather than from teeth
all on one card.

The arches are classified in a general way as
 Square
 Tapering
 Ovoid

A-SQUARE , B- TAPERING, C- OVOID

 The central incisors in a square arch form
assume a position more nearly back to the
canines than in any other setup.
 The four incisors have very little rotation as
they have sufficient room in the arch.
 This gives a broader effect to the teeth and
should harmonise with a broad square face.

 In the tapering arch, the central incisors are a
greater distance forward than the canines.
 There usually is considerable rotation and
lapping of these teeth because there is less
space in the arch.
 The narrowed effect is in harmony with the
narrower, tapering face.

 In the ovoid arch, the central incisors are
forward to the canines, in a position between
that of the square and tapering arches.
 The teeth are seldom rotated and have a
broad effect that should be in harmony with a
round , ovoid face.

 When it is decided to set anterior teeth irregularly, it
is essential that both canine cusps lie in the same
coronal plane and are equidistant from the median
sagittal plane. If this is not done the irregularities
produced in the anterior teeth will result in an
asvmmetry of the posterior parts of the arch.
 To ensure that the canines are symmetrically placed ,
the following rules should be observed regarding the
setting of the incisors, so that any irregularities will
compensate one another.

 If the angle between the incisal edge of the right
central incisor and the median sagittal plane (A’) is
less than the angle between the incisal edge of the
left central incisor and the median sagittal plane (A”),
then the angle subtended by the right lateral incisor
to the median sagittal plane (B’) should be greater
than the angle subtended by the left lateral incisor to
the median sagittal plane (B”).
 If A’ is less than A” then B’ should be greater than B”.

Method of setting the upper incisors so that rotational irregularities
compensate each other and enable the symmetrical placement of
the canines.

 In the average individual the sagittal angle between the
columella and the lip is about a right angle, but several factors
influence the actual angle in any individual.
a. If the teeth are proclined the nasolabial angle tends to be
approximately 90 , but if the teeth are retroclined the angle
tends to be more than a right angle.
b. if the columella is prominent and at a lower level than the ala,
a nasolabial angle of more than a right angle is indicated, but if
the columella and ala are at the same level this indicates a right
angle.

The effect of tooth inclination and nose form on the nasolabial angle.
A. When the teeth are proclined, the nasolabial angle is about 90 or less.
B. When the teeth are retroclined, the nasolabial angle must be more than 90 .
C. When the columella is prominent and the ala is high, the nasolabial angle is
more than 90 ‘.
D. When the columella and ala are at the same level, the nasolabial angle is
about 90

Maxillary Central Incisors
 Long axis of tooth should be
parallel to the midline when viewed
labially.
 Incisal edge is in contact with the
occlusal plane.
 Maxillary central incisors should
have a labial inclination of 15
degrees.
 Tip of incisal pin should be
touching the mesioincisal angle of
central incisors.
 Incisal edges are in a straight line
with the distoincisal edge slightly
curved.

Maxillary Lateral Incisors
 Long axis of the tooth should be
distally inclined.
 Cervically it is not as prominent
as central incisors.
 Incisal edge is 1 mm above the
occlusal plane.
 Lateral incisors should have a
labial inclination of 20 degrees.
 Incisal edges follows the curvature
of the arch

Maxillary Canine
 Long axis of tooth should be straight.
 When viewed from front, only mesial half of
tooth is visible.
 Neck of cuspid should be prominent.
 Incisal edge is tucked in to harmonize with
the adjacent incisal edge.Cusp is in contact
with the occlusal plane.
 Long axis of tooth should be parallel to the
vertical axis.
 When viewed incisally the canines are
rotated upto 90 degrees following the
curvature of arch.

Mandibular Central Incisors
 Long axis should be straight and
parallel to the midline.
 Incisal edge should be 2 mm
above occlusal plane.
 Long axis should be labially
inclined when viewed from side.
 Maxillary midline should coincide
with mandibular midline.
 Incisal edges should be in straight
line with the distoincisal edge
slightly curved.

 Mandibular Lateral Incisors
 Long axis should be parallel to the
midline.
 Incisal edge should be 2 mm
above occlusal plane.
 Long axis should be labially
inclined but not as steeply as
central incisors.
 Incisal edges follows the curvature
of arch.

Mandibular Canine
 Long axis of tooth should be
mesially inclined i.e sloping
towards the midline
 Cusp tip is slightly more than 2
mm above occlusal plane.
 Placed in a sloping manner thus
known as sleeping canine.
 Long axis should have a slight
lingual inclination when viewed
from the side.
 Canines are rotated upto 90
degrees.

Arrangement of posterior teeth
 The preliminary arrangement of posterior teeth involves the
application of principles similar to those applied in the
arrangement of anterior teeth.
 The artificial posterior teeth should be placed near to where the
natural teeth were positioned.
 This placement will make it easier for the patient to adapt to the
dentures, permits tongue and cheeks to function effectively
during speech, mastication, and deglutition, and is esthetically
more acceptable than a purely mechanical position.

 The posterior plane of occlusion is an extension of
this anterior plane level with the junction between the
middle and upper third of the retromolar pads
bilaterally.
 These posterior references (retromolar pads) will
place the overall plane at a level that is familiar to the
tongue.

 The use of these anteroposterior landmarks
also creates an occlusal plane essentially
parallel to the ala-tragus line.

 Research by Foley and Latta showed that the
parotid papilla was on the average 3.3 mm
above the occlusal plane and should be
considered and used as a guide for
establishing the height of the occlusal plane.

 If it is too high, the upper and lower posterior teeth
can bite the papilla during function.
 If the plane is too low, the tongue can overlap the
lower teeth and cause tongue biting.
 Interference with normal tongue action due to a high
or low occlusal plane will adversely influence denture
base stability .

 The curvature of the arch of anterior teeth should flow
pleasingly toward the posterior teeth.
 The posterior teeth are positioned in such a way that
they are properly related to the bone that supports
them and to the soft tissues that contact their facial
and lingual surfaces.

Regarding the anatomic landmarks used for locating the
the lower molar teeth, Pound reported that the positions of the
lower molars are situated between two lines projected from the
buccal and lingual aspects of the retromolar pad to the mesial
aspect of the cuspid.
 Also, as stated by Ortman, the lingual cusps of the natural
molars are approximately in vertical alignment with the mylohoid
ridge , and thus the mylohyoid ridge is a reliable guide for
determining the lingual limit of the artificial lower teeth.
 The lower posterior teeth must never be arranged lingually to
this ridge. Both are generally used as guides to guess the
position occupied by the natural teeth.

The lingual surfaces of the lower molars are situated between two
lines projected from the buccal and lingual aspects of the retromolar
pad to the mesial aspect of the cuspid (Pound, E).

 In the final tooth arrangement, the posterior form of
the arch will be determined largely by the “neutral
zone” between the cheeks and tongue.
 This is the space resulting from the removal of the
posterior teeth and the loss of bone from the residual
ridges.

 Therefore the final arrangement of the arch must be developed
with respect for the tongue and cheek .
 The solution to the problem is to position the teeth along a line
extending from the tip of the canine to the middle of the
retromolar pad.
 This arbitrary line should pass through the central fossa of the
mandibular premolars and molars.

 The basic principle for the buccolingual positioning of
posterior teeth is that they should be positioned over
the residual ridge.
 The canine and retromolar pad should provide guides
for this arrangement.
 The distance between the distal of the mandibular
canine and the mesial of the retromolar pad is
measured to determine the total anterposterior space
to be covered.

 The maxilla does not afford a landmark to
which to measure, while the mandible rises
with an upward curvature and prevents a
setting of the teeth too far to the posterior.

 A point ito 2 mm below the top of the retromolar
pad and the tip of the positioned mandibular cuspid
are guides used in the placement of the mandibular
posterior teeth.
 The central grooves of the posterior teeth are
positioned on a line between the cuspid tip and the
middle of the retromolar pad. When only three
posterior teeth are arranged, it is essential that the
central grooves of the molars be positioned slightly
to the buccal to avoid crowding the tongue.

 The key to an ideal, anatomically related setup of the upper and
lower posterior teeth is the proper relationship between upper
and lower canines.
 When correctly related , the mesial incline of the upper canine
opposes the distal incline of the lower canine.

Maxillary 1st Premolar
 Long axis should be straight
 Palatal cusp should coincide with
the crest of the lower residual ridge
 Buccal cusp should touch the
occlusal plane.
 Palatal cusp should be 1mm above
the occlusal plane

 Maxillary 2nd Premolar
 Long axis should be straight
 The palatal cusp should coincide
with the crest of the residual ridge
 Both Buccal and Palatal cusps
should contact the occlusal plane

 Maxillary 1st Molar
 The long axis should be inclined mesially
when viewed from the buccal aspect .
 The mesiopalatal cusp should
coincide with the crest of the
lower residual ridge.
 The long axis should be inclined
palatally when viewed from the
proximal aspect .
 The mesio-palatal cusp should
contact the occlusal plane.
 Distobuccal cusp should be 0.5mm
above the occlusal plane
 Distolingual cusp 0.5 – 0.75mm
 above the occlusal plane

Maxillary 2nd Molar
 Long axis should be inclined mesially
when viewed from the buccal aspect.
 The mesial tilt should be more than
that of the 1st molar .
 Mesiopalatal cusp should coincide
with the crest of the lower residual ridge;
but be 0.75mm above it.
 Long axis should be inclined palatally
when viewed from the proximal aspect.
 All cusps should be above the
occlusal plane. The mesiopalatal cusp is
the closest to the occlusal plane (0.75mm)

 Mandibular 1st
molar
when viewed from the buccal aspect
 Long axis should incline lingually when
viewed from proximal aspect.
 All cusps should be at a higher level
 than the occlusal plane
 Mesiobuccal cusp should occlude
with the distal marginal ridge of the
maxillary 2nd premolar and the
mesial marginal ridge of the
maxillary 1st molar.
 The mesiobuccal cusp of the
maxillary 1st molar should occlude
in the buccal groove of the
mandibular 1st molar.

 Mandibular 2nd
molar
when viewed from the buccal aspect.
 Long axis should incline lingually when
viewed from the proximal aspect.
 All cusps should be above the
occlusal plane .
 Mesiobuccal cusp occludes with the distal
marginal ridge of maxillary 1st molar
& mesial marginal ridge of the
maxillary 2nd molar

Mandibular 2nd
premolar
 Long axis should be straight when
viewed from the buccal aspect .
 Both cusps should be 2mm
above the occlusal plane.
 The buccal cusp occludes with the
mesial marginal ridge maxillary
2nd premolar and the distal marginal
ridge of the maxillary 1st premolar

Mandibular 1st
premolar
 Long axis should be straight when
viewed from the buccal aspect .
 Buccal cusp should be 2mm above
the occlusal plane.
 Lingual cusp tip should lie below
the occlusal plane .
 Tip of the buccal cusp should contact
with the mesial marginal ridge of the
maxillary 1st premolar and mesial
marginal ridge of the maxillary 1st premolar

Arranging the premolars and the modiolus
 At the corner of the mouth situated almost in the
position of the lower first premolar, many muscle
fibers of the muscles of mastication and expression
such as the buccinator and orbicularis oris converge
to form a muscle knot called the modiolus.
 When the buccinator, the orbicularis oris, etc.
contract during functional movements such as
mastication or speech, the modiolus strongly pushes
the buccal side of the premolar region.

 The buccinator, which contracts during mastication, can produce an
effective muscle contraction only if its anterior and posterior ends
are fixed.
 Its anterior end is at the modiolus which is supported by the first
premolar.
 Therefore, if the first premolar is placed more lingually to the
position of the natural teeth, the buccinator will lose its support
during function and can not function effectively during mastication
as in the dentate state.
 To perform its functions smoothly, the first premolar should be
arranged in the position of the natural teeth, namely buccally to the
alveolar crest.

When the lower posterior teeth are placed where the
natural teeth were situated, one has to also consider
the size of the artificial teeth.
 An undercut tends to occur increasingly under the
lower molars of the natural dental arch as it is
followed posteriorly. So, also in the denture, if the
artificial teeth are arranged in the position occupied
by the natural teeth, an undercut will be produced on
the lingual polished surface under the posterior teeth.
 The tongue will bulge into the undercut and raise the
denture, causing it to be dislodged.

 The occlusal surface area of the artificial posterior
teeth is smaller than that of the natural teeth in order
to reduce the load on the supporting tissues during
mastication. This will also work effectively in this
situation.
 The use of posterior teeth which are narrow
buccolingually will produce no undercut under the
teeth. More favorably, these teeth are also smaller
mesiodistally, so that the position of the posterior
teeth shifts mesially where there is less undercut in
the natural dentition.

 If the posterior teeth are arranged in the position
where the natural teeth were, the undercut will also
occur on the lingual polished surface under the teeth.
The tongue will bulge into the undercut and raise the
denture. www.indiandentalacademy.com

If posterior teeth which are narrow buccolingually are
used, no undercut will occur lingually under the teeth.

As the artificial posterior teeth are smaller
mesiodistally, the position of the posterior teeth
shifts mesially where there is less undercut in the
natural dentition.

 By using artificial teeth which are much
smaller than the natural teeth, a large tongue
space can be obtained.
 In addition, the forces from the cheeks and
tongue will be balanced. So, this situation can
resolve problems arising in edentulous
patients, who typically have a large, strong
tongue.

 Compensating curves
 From the foregoing descriptions of the orientation of
the teeth it will be seen that they are arranged so that
the posterior teeth, when considered as a whole unit,
form two curves
 antero posterior and
 lateral curve.

Anteroposterior curve

Compensating curves are the artificial curves introduced into dentures
in order to facilitate the production of balanced articulation: they are the
artificial counterparts of the curves of Spee and Monson which are
found in the natural dentition.
 The anteroposterior curve follows an imaginary line touching the buccal
cups of all lower teeth from the lower canine backwards,and
approximates to the arc of a circle.
 A continuation of this curve in the natural dentition (curve of Spee) ,
will nearly always pass through the head of the condyle .

The curve of Spee of the natural dentitionwww.indiandentalacademy.com

 If the path followed by the condyles is horizontal, then the teeth
could be set to conform to a horizontal plane. When the
mandible moves forwards the teeth will remain in contact.

 If the path travelled by the condyles is at an angle from the
horizontal plane (as it always is to some extent), then as soon
as the mandible moves forwards the condyles commence to
descend, and the posterior teeth will lose contact if they have
been set to conform to a horizontal plane.

 If the posterior teeth, instead of being set on a
horizontal plane, are set to an anteroposterior curve
then as the mandible moves forwards and the
condyles travel downwards all the teeth can remain in
contact.

(a) Retruded contact position with an occlusal
surface which is an arc of the circle of which the
condylar path is also an arc.
(b) In protrusion, contact is maintained

 The lateral curves
 In the natural dentitjon there are two lateral curves, one
involving the molar teeth (the curve of Monson), and the other
involving the teeth anterior to the second premolars.
 The second premolars are not involved in any curve as they lie
on a horizontal plane.
 The posterior curve has its concavity facing upwards and
increases in steepness from before backwards, the occlusal
surfaces of the upper molars facing outwards and downwards.
The anterior curve is a reverse of the posterior curve just
described.

Lateral compensating curves
(a) Molar curve; (b) second premolar; (c) first premolar curve

 When the mandible is moved laterally the rotating
condyle on the working side (i.e. the side towards
which the mandible is moved) remains in the glenoid
fossa and moves very slightly outwards and
backwards (Bennett movement).
 The orbiting condyle on the other side (balancing or
non-working side) travels downwards and forwards.

 If the teeth are set on a horizontal plane, those on the
non-working side will lose contact, due to the
downward movement of the condyle on that side. If,
however, the teeth are set to conform to a curve, the
steepness of which relates to the steepness of the
condylar path, then the teeth will remain in contact
during the lateral and downward movements .

Ridge relations
The anatomic structure of the maxilla and
mandible is such that they tend to resorb from
each other, i.e., the mandible becomes wider
and the maxilla narrower because the
inclination of the alveolar process is upward
and inward in the maxilla and outward and
downward in the mandible.

Natural teeth in normal (80 degree) inclination.
Lines a,b,c,d show successive stages of resorption and increasing
disparity between the widths of the arches.

Resorption does not take place in parallel levels.
The solid outlines show successive forms of ridges ; at stage d, the
intra alveolar crestal angle is only 73 degrees

The ridge relations may be classified as
 Prognathous – anterior and posterior teeth of the maxilla are set to
the lingual instead to the buccal of the mandibular teeth.
Cross-bite A is a ridge relation that is normal in the anterior portion
of the mouth and prognathic in the posterior ridge relation.
Cross-bite B is a combination of ridge relations that may be
classified as normal in the posterior areas and prognathic in the anterior
part of the mouth.
Crossbite A is a ridge relation that is very common, while crossbite
B is rarely found. These combinations of ridge relation are caused by
intermittent premature loss of teeth with no replacements.
 orthognathous - retrusion of the mandibular anterior teeth with the
posterior teeth in normal relation to each other.

Crossbite A relation
Anterior relation Posterior relation

Crossbite B

Orthognathous relationship

Atypical arrangement of teeth
Tooth overlap of patients with maxillary protrusion
 In patients who had an Angle’s Class II. division 1 malocclusion
in their natural dentition, in order to provide a good appearance,
it is not uncommon for the upper anterior teeth to be arranged
more lingually than their normal position and sometimes even
some of the alveolar process is removed to arrange the teeth
further back. In this way, the prominent appearance is removed
and the appearance of the patient is apparently improved.
 However, if one sticks to arranging the teeth posteriorly, the
tension of the upper lip will be lost and a youthful appearance
may disappear.

Patients having maxillary protrusion are characterized by a
deep vertical overlap of the anterior teeth and a marked forward
movement of the mandible.

 Also, a deep vertical overlap of the anterior teeth and
a marked forward translation of the mandible during
function are characteristic of these cases.
 If this is neglected and the anterior teeth are
arranged posteriorly, the horizontal overlap will
reduce and the large mandibular movement during
function will be hindered.
 The dentures may be displaced by the anterior teeth
impacting during function.

 Therefore, in order to improve the appearance of
those patients with maxillary protrusion without loss
of denture retention, a method is used in which the
upper anterior teeth are arranged at a higher level
than the natural teeth without altering their
anteroposterior position. Thus, the deep vertical
overlap is reduced, leading to improvement in the
facial appearance and a smoothing of the mandibular
movements.
 It is important to give a shallow incisal guide
inclination for good denture stability.

POSTERIOR ARRANGEMENT FOR CLASS II RELATIONSHIP
 The lower ridge is small and markedly inside the
upper ridge. The anterior teeth exhibit a pronounced
horizontal overlap when they are arranged properly
for esthetics.
 The upper posterior teeth may need to be set more
palatally than usual in order that they may occlude
with the lower teeth.
 The lower teeth should never be set outside the
ridge .

 Either anatomic, modified anatomic, or nonanatomic
teeth can be used for these retrusive cases.
 The selection of the occlusal form is based on the
same factors of ridge strength, form, and interridge
space as for the normal ridge relation.
 Because the lower ridge in these patients is usually
small and weak in relation to the upper, the
buccolingual inclines are modified to a shallow
angulation, or nonantomic teeth are selected.

Tooth overlap of patients with mandibular protrusion
 Many patients with mandibular protrusion have a marked translation of
the mandible during function, similar to those patients with maxillary
protrusion. Therefore, even though the appearance of the patient can
be improved as much as they expect, the upper anterior teeth should
not be arranged to cover the lower anterior teeth regardless of a
marked mandibular movement and the relationship of the upper and
lower residual ridges.
 In patients with mandibular protrusion, arranging the teeth in an edge-
to-edge-like incisal relationship (the upper and lower anterior teeth are
not in contact) is the limit.

In the case of mandibular
protrusion, the anterior teeth
should be arranged in an edge-to-
edge- like relationship. If possible,
the upper anterior teeth should be
arranged more labially than their
natural position.

 The anterior teeth are best set edge to edge or, in
extreme cases, with a negative overjet .
 An edge-to-edge relationship, although it may appear
difficult to accomplish, is almost always possible by
retro-inclining the lower incisors and setting the upper
incisors more labially, especially at the incisal edge.

 When setting the posterior teeth it is often difficult to
occlude them in a normal relationship because of the
discrepancy between the ridges, particularly in the
molar region.
 In extreme cases it may be necessary to reverse the
tooth relationship .
 This means that instead of the buccal cusps of the
lower molars fitting into the fossae of the upper
molars, the reverse occurs.

 Sometimes the crossing of the occlusion has to be
applied to all the posterior teeth, but more commonly
it is only the molars which are affected.
 In cases presenting marked inferior protrusion it is
frequently necessary to set the upper teeth far
outside the ridge and it is then important that the
buccal flange is sufficiently wide that the polished
surface has the correct shape .

 If the retention of the denture is satisfactory the only
trouble likely to result from setting teeth over the
buccal sulcus is a midline fracture of the denture due
to its continual flexion, particularly if the occlusion is
not balanced, and a metal palate may be
incorporated.

Arranging teeth to a balanced
articulation
 The objective of balancing a denture occlusion is to create
simultaneous bilateral contacts from the centric relation position to
all eccentric occlusal positions that are free of interferences.
 These multiple contacts should be smooth, uniform, and in
harmony with the temporomandibular joints and neuromuscular
activity.
 Once achieved, first by the proper positioning of the teeth during
the setup and then refined by selective grinding, a lingual contact
balanced occlusion also provides lever stability for the denture
bases.

Prerequisites for Balancing the Occlusion
 There are four specific conditions that must be met by the
mandibular posterior teeth in order to achieve a balanced
occlusion:
(1) the mandibular posterior teeth must be set so that the
occlusal surfaces are horizontal;
(2) the plane of occlusion must have a proper orientation;
(3) a compensating curve must be set; and
(4) the teeth must be modified so that there are no interlocking
transverse ridges.

The maxillary teeth must be
(1) modified to eliminate buccal cusp contact,
(2) set so that the upper lingual cusps have a positive
but static centric occlusal contact, and
(3) have no buccal cusp contacts in lateral excursions

 The anterior teeth are set with a minimal
vertical overlap of 0.5 to 1mm and 1 to 2 mm
of horizontal overlap to establish a low incisal
guidance.

 In the arrangement of posterior teeth, most clinicians
set the mandibular teeth before the maxillary
because this provides better control of the orientation
of the plane of occlusion both mediolaterally and
superoinferiorly .

Setting the mandibular teeth
Premolars
 The primary consideration in positioning the premolars is that
they follow the form of the residual ridge.
 The central fossa should be in line with the antero posterior
reference line.

 The facial surface of the premolars should be perpendicular to
the occlusal rim, and yet slightly facial to the canine, but never
farther facially than the buccal flange.
 In the ideal situation, the mandibular first and second premolars,
with their central grooves, are positioned on a line from the
canine tip to 1 to 2 mm below the top of the retromolar pad.

 The long axis of the tooth is positioned so that the
cusp tips are level with the remaining mandibular wax
occlusal rim.
 The second premolar is set in a similar manner.

 When these lower teeth have been arranged, a
segment of the maxillary occlusal rim is removed to
accommodate the first maxillary premolar, which is
set into maximum intercuspation with the two lower
premolars.

 The first three premolars set (two mandibular and one maxillary)
are the key to the relative anteroposterior intercuspation of all
the remaining posterior teeth.
 Once the premolars are set and properly related to each other,
positioning of the remaining mandibular posterior teeth is easily
accomplished.

Molars
 The mesial cusps are on the plane established by the anterior
teeth and bicuspids.
 The distal cusps of the first molars are raised about 0.5 mm
above this plane.
 The buccal and lingual cusps are set at the same height to
make the transverse plane horizontal.
 The central fossa is aligned with the canine – retromolar pad
reference line.

 The second molar continues the cuspal elevation of
the compensating curve.
 This imaginary extension should run parallel to the
condylar inclination.
 The buccal and lingual cusps are horizontal and the
central fossa is aligned with the canine – retromolar
pad reference points.

Setting maxillary posterior teeth
Premolar
 The first premolar is placed next to the canine and
the articulator is closed to its proper vertical and
central position.

 The tooth is guided so that the lingual cusp fits into
the lower common central fossa at the midpoint of
the distal marginal ridge of the first mandibular
premolar and the mesial marginal ridge of the second
molar.
 The buccal cusp is raised slightly out of contact.

 The second premolar is placed with the
lingual cusp in contact with the central fossa
at the midpoint of the distal marginal ridge of
the mandibular second molar and mesial
marginal ridge of the mandibular first molar.

Molars
 After these adjustments are completed, the maxillary first molar
is articulated with the mandibular first molar.
 After the maxillary first molar is positioned, the articulator is
closed so that the mandibular tooth will assist in seating the
maxillary tooth into maximum intercuspation.
 This will develop the desired lingual cusp contact of the
maxillary molar in the central fossa of the mandibular
antagonist.

 The maxillary first molar is set with a slightly more
buccal tilt than the maxillary second premolar.
 The tooth will have a mesial inclination dictated by
the amount of compensating curve established by the
mandibular molars.
 The mesiolingual cusp sets into the central fossa of
the mandibular first molar and the distolingual cusp
contacts the centers of the distal marginal ridge of the
mandibular first molar and the mesial marginal ridge
of the second molar in centric occlusion .

 The maxillary second molar should be set with
slightly more buccal tilt and its mesiolingual cusp
contacts the central fossa of the lower second molar.
 Once the teeth are set and securely luted in place
and the wax has cooled, the placement of the lingual
cusps is inspected from the distal aspect of the
articulator .
 All of the upper lingual cusps should occlude in the
common central fossa of the modified lower teeth.

 Without this as a starting point, a stable static centric
occlusion is not possible.
excursions.
 The right and left lateral excursions for the completed
unilateral setup are then checked. There should be
working and balancing contacts that are in harmony
with the guidance of the condylar inclination and
incisal guidance.
 Ideally, in this occlusal scheme there should be five
working cusp contacts, five balancing cusp contacts,
and no upper buccal cusp contacts.

 This ideal is seldom achieved at this stage of the setup. There
are usually some prematurities on lower buccal or lingual
inclines; however, the teeth should have potential for contact by
slight selective grinding.
 When functioning as balancing contacts, upper lingual cusps
ride over the lower buccal (lingual-facing inclines) cusp inclines
diagonally.
 When acting as working cusps, upper lingual cusps pass
between modified triangular ridges of the lower lingual cusps
that run either to the marginal ridge or to the groove between
the cusps of the lower molars.

 When viewed from the back of the articulator all of the upper
lingual cusps should occlude in the lower central fossa as
described.
 These are the centric occlusion holding contacts. Since the
lower teeth were set to fixed criteria and securely waxed into
position, all adjustments to the occlusion at this time are made
by altering the position of the upper teeth.
 Until these contacts are precise and secured with wax, the
upper posterior setup is incomplete.

 There should be simultaneous working and balancing contacts
bilaterally.
 In protrusive excursion the lingual cusps of the upper right and
left second molars should glide up the distal inclines of the lower
second molars. There should be no cuspal collisions of other
posterior teeth to mar a smooth excursion.
 As the protrusive excursion brings the upper and lower anterior
teeth in apposition, they should just glide by each other under
the guiding factors of the compensating curve and the condylar
inclination.

 This initial balance achieved during the setup of the upper
posteriors must be further refined by selective grinding.
 The occlusion is examined again to check for any tooth
movement.
 The dentures are now ready for the try-in. After verification of
the trial dentures in the mouth, the dentures are returned to the
articulator for final waxing and refining of the occlusion.
 Small dicrepancies in the initial setting as well as errors due to
small tooth movements during the final waxing are corrected by
judicious selective grinding.

The black diamonds indicate the maxillary lingual cusp contact area. The
arrows indicate the paths of the maxillary lingual cusps in balancing,
working, and protrusive excursions.

Selective Grinding for Static Centric Contacts
 Once the initial balance is achieved during the setup of the
maxillary posteriors, the complete occlusion must be refined by
selective grinding.
 A length of thin articulating paper is placed on the posterior
teeth, and the articulator is gently tapped several times in
centric occlusion.
 There should be marks on each of the areas shown .
 If marks show on lower cusp inclines, the inclines are ground to
eliminate deflective contacts.

 If there are any upper lingual cusps out of contact, the
nonoccluding maxillary teeth are repositioned by moving the
lingual cusps down into contact.
 Only the lower central fossae or marginal ridges should be
ground, not the upper lingual cusps.
 If any significant grinding is done on the lower teeth, the
occlusal vertical dimension will be reduced and anterior
interference will occur.

 If any upper buccal cusps or inclines are in contact, they should
be ground out of contact.
 Only the upper lingual cusp, that is, the pestle of the mortar-
and-pestle-type lingual contact occlusion, should articulate with
the lower posteriors .
 The final result after several tappings and spot grindings should
be stable contacts with all upper lingual cusps in the common
lower central fossae. The occlusion is now ready to be refined
for working and balancing contacts.

Selective Grinding for Working and Balancing Contacts
 When the mandible moves to the left, this becomes the working
side.
 The upper left lingual cusps should contact the lower left lingual
cusps.
 The right side is then the balancing side, and the upper lingual
cusps should contact the lower buccal cusps.
 Only one lateral excursion (either the left or right) should be
checked at a time.

 A strip of thin articulating paper is placed between the
posterior teeth bilaterally.
 While keeping gentle pressure on the maxillary
member of the articulator, move it to the right (this is
equivalent to moving the mandible to the left). This
duplicates a left lateral excursion.
 Ideally, in this occlusal scheme there should be five
working cusp contacts, five balancing cusp contacts,
and no upper buccal cusp contacts.

 When functioning as balancing contacts, upper lingual cusps
ride lower buccal (lingual-facing inclines) cusp inclines
diagonally.
 When acting as working cusps, upper lingual cusps pass
between modified triangular ridges of the lower lingual cusps
that run either to the marginal ridge or to the groove between
the cusps of the lower molars .
 There usually is some prematurity on the working or balancing
side that prevents total working or balancing cusp contact. Grind
the marked premature balancing contacts, heavily marked
working side contacts, or both, on the lower teeth.

 By selectively spot grinding the premature inclines and cusps, a
smooth harmonious multiple contact of the desired contacts will
occur.
 Do not grind the upper lingual cusps. Do not grind the lower
buccal cusps. There should be no upper buccal cusp contact in
any excursion.
 As the premature inclines and high cusps are selectively ground
until there is simultaneous contact of working and balancing
cusps, the cusp rise is gradually reduced.
 This may create anterior inerference on the working side, which
must be eliminated.
 Usually, there is sufficient compensating horizontal overlap for
any vertical overlap to allow for a simple solution by grinding.

 The lingual of the upper anterior incisal edges and
the labial of the lower anteriors are ground to
eliminate any interference that develops while
selectively grinding to balance the occlusion.
 Grinding on the anterior teeth should always be
conservative so that the esthetic value of the anterior
teeth is not disturbed.
 The finished result should be a smooth gliding left
lateral excursion with ten simultaneous working and
balancing contacts (five working and five balancing
contacts).

 Selective Grinding for Protrusive Balance
 The upper right and left second molar cusps should
ride up the distal inclines of the lower right and left
second molars with enough rise to clear the anteriors.
 There should be no interference between the buccal
cusps of the upper teeth and any of the lower buccal
cusps.
 If anterior interference occurs, either move or grind
the lower offending anterior tooth slightly or increase
the distal incline on the lower second molar by
increasing the compensating curve.

 Polishing the Teeth
 The surfaces of any ground teeth should be polished to
eliminate friction between occluding surfaces.
 Friction is greater between porcelain surfaces than between
acrylic surfaces. This increases the incidence of chipping in
porcelain teeth.
 Porcelain teeth should be smoothed and polished with a rubber
porcelain polishing wheel until each lateral excursion is free of
grating or frictional drag. Final polishing can be achieved with a
felt wheel and aluminum oxide.
 Acrylic teeth can be smoothed with pumice and polished with
acrylic polish.

NONANATOMIC (ZERODEGREE)
POSTERIOR SETUP
 Prosthodontics has always been concerned with the
maintenance of the remaining supporting structure.
 It is now widely accepted that cusped teeth, such as the
modified anatomic setup, if properly coordinated with one
another and with mandibular movements, provide an efficient
and esthetically pleasing posterior setup for many patients. The
presence of cusps, however, does introduce horizontal thrusts.

 Many severely resorbed or generally debilitated
ridges may not stand these potentially destructive
forces.
 Nonanatomic posterior teeth were designed to favor
these types of ridges by minimizing the horizontal
component of force during mastication and during
parafunctional movements.

 The indications for the use of flat teeth are as follows:
(1) flat ridges,
(2) knife-edge ridges
(3) large interridge space,
(4) milling type of chewing pattern with broad
excursions, and
(5) where debilitation has reduced the patient’s
coordination needed to handle a cusped type of
occlusion.

 The flat teeth occlude in two dimensions (length and width), but
the mandible, because of the incline of the condylar path,
moves in a three-dimensional accurate path.
 The loss of the vertical component (cuspal rise) in flat teeth
alters the protrusive and bilateral balance that is possible with
cusped teeth.
 The traditional amount of anterior vertical overlap must also be
eliminated or modified in order to avoid anterior interference in
lateral and protrusive excursions.

The arrows indicate the direction and magnitude of
forces that are brought to bear on the denture
foundation during mastication.

Mandibular Setup
Anteroposteriorly
 The position and height of the lower first premolar is governed
by the height of the lower canine.
 The marginal ridges should be confluent and rise with a slight
curve of Spee starting at the first molar.
 The distal of the second molar should be at the height of the
center of the retromolar pad.

Buccolingually
 The center of the teeth should be a straight line from the tip of
the canine to the apex of the retromolar pad. The lower occlusal
table should not be buccal to the residual ridge or lingual to the
mylohyoid ridge.
Laterally horizontal
 The lower teeth should be horizontal. No lingual tilt (Monson
curve) should be set.

Maxillary Setup
 Anteroposteriorly
 There is no mesiodistal exactness needed as with cusped teeth,
since there is no interdigitation of cusps.
 Buccolingually
 The upper teeth should be set on the lower teeth ‘flat-on-flat”
rather than with a buccal cusp rise as in the cusp setup .
 Buccal overjet of approximately one half the width of the tooth
should be set to prevent cheek biting. Be sure that the lingual
portion of the upper teeth is in contact with the center area of
the lower teeth.

Monoplane teeth are set on a horizontal plane and
horizontally to each other.

Lingualised occlusion
 Lingualized occlusion is an attempt to maintain the
esthetic and food-penetration advantages of the
anatomic form while maintaining the mechanical
freedom of the nonanatomic form.
 The lingualized concept utilizes anatomic teeth for
the maxillary denture and modified nonanatomic or
semianatomic teeth for the mandibular denture.

Indications
 It is particularly helpful when the patient places high
priority on esthetics but a nonanatomic occlusal
scheme is indicated by oral conditions such as
severe alveolar resorption, a Class II jaw relationship,
or displaceable supporting tissue. If the nonanatomic
occlusal scheme is used, esthetics in the premolar
region are compromised. With lingualized occlusion,
the esthetic result is greatly improved while still
maintaining the advantages of a nonanatomic system
.

 The goal for bilateral balanced occlusion with
lingualized occlusion should be to achieve
smooth bilateral contact with excursive
movements of 2 to 3 mm away from centric
relation.

PRINCIPLES OF LINGUALIZED
OCCLUSION
(1) Anatomic posterior 30 or 33 degree teeth are used
for the maxillary denture. Tooth forms with prominent
lingual cusps are helpful.
(2) Nonanatomic or semianatomic teeth are used for the
mandibular denture. Either a shallow or flat cusp form
is used. A narrow occlusal table is preferred when
severe resorption of the residual ridges has occurred.
(3) Modification of the mandibular posterior teeth is
accomplished by selective grinding which is always
necessary regardless of specific tooth or material.

(4) Maxillary lingual cusps should contact mandibular
teeth in centric occlusion. The mandibular buccal
cusps should not contact the upper teeth in centric
occlusion, as is customary with usual anatomic tooth
placement .
 It is helpful to slightly rotate the maxillary posterior
teeth buccally to allow for slight clearance of the
buccal cusps in the working position and to reduce
the need for extensive grinding.

(5) Balancing and working contacts should occur only on the
maxillary lingual cusps. The posterior teeth are arranged and
adjusted to establish bilateral balanced occlusion in lateral
mandibular excursions for a range of 2 to 3 mm around centric
relation .
 Selective grinding of the maxillary buccal cusps may be needed
to create a small clearance between the maxillary and
mandibular buccal cusps on the working side when excursive
movements are initiated.
 The maxillary lingual cusps remain in contact on the working
side. This helps to reduce lateral movement of the lower denture
by placing occlusal forces more lingual to and toward the center
of the mandibular teeth.
 On the balancing side the maxillary lingual cusps contact the
mandibular buccal cusps as is customary with anatomic
occlusal arrangements.

(6) Protrusive balancing contacts should occur only between the
maxillary lingual cups and the lower teeth. Reduction of
anteroposterior interferences on the mandibular teeth may be
necessary in order to provide a range of balanced occlusion in
the protrusive position.
 Selective grinding for protrusive movements should be done
only on the mandibular teeth so that lateral balancing contacts
and the vertical dimension of occlusion are not changed.
 After processing, the dentures are remounted on the articulator
and the occlusion is refined to create smooth, simultaneous
contacts between the teeth during excursive movements.

 In the arrangement of the teeth for lingualized
articulation, the mandibular teeth are set first
to establish the occlusal plane.

Teeth arrangement for esthetics
 The arrangement of the teeth should be
individualized to the patient’s cosmetic
needs.The teeth must look like they belong in
the patient’s mouth.
 Frush and Fisher suggested guidelines for
selection and arrangement of anterior teeth
based upon the patient’s age, sex, and
personality.

 Arrangements to meet esthetic requirements are
usually associated with the composition, size, shape
and color of the six anterior teeth. However, the
horìzontal and vertical positions of posterior teeth are
intimately involved in facial expression .
 The general features and asymmetries should be
observed and recorded during the first appointment
with the patient.

Age
 Age is often revealed by the amount of
maxillary and/or mandibular teeth that show
during rest or function.
 With increasing age, the amount of maxillary
central incisors exposed when the lips are
gently parted decreases from 3 + mm at age
29 to no tooth showing at 60 years of age.
The opposite occurs for the mandibular
incisors, with approximately 0.5 mm showing
at age 29 and 3 mm showing at age 60.

 Frush and Fisher state that the dignity of
advancing age can be successfully portrayed
in the denture by careful tooth color selection
and mold refinement.
 By varying the long axis of the teeth, using
diastemata, and grinding the incisal edges,
the appearance of the anterior teeth can be
transformed from youthful to advanced in
age.

 As muscle tonus decreases,the position of the teeth
for support to the lips and cheeks are more critical.
 Teeth abrade with age.the central and lateral incisors
abrade in a straight line,and canines in a curve.
 The wearing away of teeth creates spaces between
teeth.
 The smile line is sharp in younger people than in the
older people.

Sex
 Square features are associated with males and
curved features with females.
 Roundness ot the arch form denotes femininity, and
squareness denotes masculinity.
 The incisal edges of the maxillary anterior teeth of
females follow the curve of the lower lip.

characteristics
 Flat labial surface,mesiodistally
and incisogingivally.
 sharper mesioincisal and
distoincisal angles
 Broad arch form; central
incisors slightly turned in on the
mesial side.
 For the male, the mesial
surface of the lateral incisor is
often hidden behind the distal
surface of the central incisor.
The distal surface of the lateral
incisor is rotated very slightly in
a posterior direction .
Feminine characteristics
 Curved labial surface—
mesiodistally and
incisogingivally
 Rounded mesioincisal and
distoincisal angles
 Tapered or curved arch form;
central incisors turned in at the
distoincisal edge.
 the mesial surface of the lateral
incisor is often seen in an
anterior relation to the
distolabial surface of the central
incisor. The distal surface of the
lateral incisor is rotated in
posterior direction. The smile is
softened as a result of this
arrangement
Masculine

 incisal edge of lateral incisor
often at same level as central
incisor
 Broad lateral incisors
 canines more prominent and
turned out at the incisal
edge
 The canines for males are
rotated less in a posterior
direction. The mesial two thirds
of the labial surtace is exposed
when viewed from the front .
 Incisal edge of lateral incisor
raised compared to central
incisor and canine
 Narrow lateral incisors.
 Canines arranged to appear
turned in at the incisal edge
(inclined palatally)
 The distal surfaces of the
canines for females are rotated
in a posterior direction; the
mesial third of the labial surface
is exposed when viewed from
the front.

Feminine type of smile line
Masculine type of smile line

Incisal edges of maxillary anterior teeth. Acceptable curvature of up (1 and
2) as guide for arranging artificial teeth for esthetics and function;
unacceptable reverse curve (3).

Personality
 The personality of a person is expressed in their
behavioural patterns and qualities of behaviour. Their
personality can be influenced by the appearance of
their teeth.
 It is the obligation of the dentist to arrange artificial
teeth in a manner to encourage the development of
an attractive personality.

 Attempting to position and shape the teeth to
complement the patient’s personality involves getting
to know the patient.
 Frush and Fisher have used a “personality spectrum”
ranging from delicate to medium pleasing to vigorous.
 The delicate personality is fragile and frail, while the
vigorous is hard and aggressive. These personalities
have ranges and blend with the medium personality,
which is more moderate and somewhat robust. A
small segment of the population has a delicate
personality, while a slightly larger group is vigorous.
The vast majority is in the medium range but tends
toward the delicate or vigorous.

Most men are found to be toward the vigorous end of the spectrum and most
women are found to he toward the delicate end of the spectrum. However,
both may still be within the broad medium personality band.www.indiandentalacademy.com

 1. Delicate—meaning fragile, frail, the
opposite of robust.
 2. Medium pleasing—meaning normal,
moderately robust, healthy and of intelligent
appearance.
 3. Vigorous—meaning the opposite of
delicate; hard and aggressive in appearance,
the extreme male animal, muscular type,
almost primitive, ugly.

 The central incisors play the dominant role in
establishing the personality, followed by the
canines and finally the lateral incisors.
 A variation in their shade as well as in the
long axis of their alignment contributes to the
overall success of the final dentures.

Prosthodontic care is not the direct
responsibility of the dental laboratory
technicians. The dentist – the professional
oral physiologist – must perfect the trial
denture to make it harmonise with the
stomatognathic system of the patient,
frequently a most challenging experience.

Review of literature
 Ortman H.R. and Tsao in 1979 conducted a
study on the relationship of the incisive
papilla to the maxillary central incisors and
stated that the average distance between the
most anterior point of the maxillary central
incisors and the most posterior point of the
papilla was 12.454 mm with a standard
deviation of 3.897 mm.

Okane H. et al in 1979 conducted a study on the effect of
anteroposterior inclination of the occlusal plane on biting force
and concluded that
1.Biting force during maximum clenching was the greatest when
the occlusal plane was made parallel to the ala tragus line.it
decreased when the occlusal plane was inclined about 5
degrees anteriorly or 5 degrees posteriorly .
2. The efficiency of biting force exertion during maximum clenching
showed the best value when the occlusal plane was made
parallel to the ala tragus line.

 Foley P.F. and Latta in 1985 conducted a
study on the position of the parotid papilla
relative to the occlusal plane and concluded
that a fairly constant relationship exists
between the parotid papilla and the occlusal
plane. An additional finding was that this
relationship may not be the same on each
side of the mouth.

 saunders,1925 , Schlosser RO et al reported a high
percentage of edentulous cases having consistency
between the face form and arch form . A continous
line drawn along the alveolar crest as far as the
tuberosities and just posterior to the junction of the
hard and soft palate when inverted and
superimposed onto the face was to correspond with
the chin margin,jaw lines,cheek lines and eyebrows.
Artificial tooth selected to arch form and therefore
face form produced esthetically pleasing effect.

 Goyal B.K.and Bhargava in 1974 did a study on
Arrangement of artificial teeth in abnormal jaw
relations: Maxillary protrusion and wider upper arch,
and Mandibular protrusion and wider lower arch,and
concluded that the upper-lower ridge relationship is
an individual problem for each complete denture
patient.One has to deviate from the usual procedures
to achieve successful results.

 Mavroskoufis F. in 1981 conducted a study on the Nasal width and
incisive papilla as guides for the selection and arrangement of
maxillary anterior teeth, and concluded that the interalar nasal width
is a reliable guide for selecting the mold of anterior teeth, and that
the incisive papilla provides a stable anatomic landmark for
arranging the labial surfaces of the central incisors at 10 mm
anterior to the posterior border of the papilla.
 The mesiodistal width of the set of anterior teeth (four incisors and
the mesial halves of the canines) should be determined by adding 7
mm to the patient’s nasal width .
 The tips of the canines on the horizontal plane, should be set on a
line which passes through the posterior border of the incisive papilla
.
 The distance between them should equal the patient’s nasal width,
so that from the frontal view they would each seem to lie on a
perpendicular line drawn from each of ala of the nose.

 Bissasu M. in 1999 conducted a study on the Use of lingual
frenum in determining the original vertical position of mandibular
anterior teeth and concluded that
1. The measurement of the distance between the AALF (anterior
attachment of the lingual frenum) and the incisal edges of
mandibular incisors is reliable when the frenum is recorded
during function.
2. The position of the AALF can be considered a relatively stable
anatomic landmark when the frenum is recorded during
function.
3. The distance between the AALF and the incisal edges of the
mandibular central incisors can be used on preextraction
diagnostic casts, made from irreversible hvdrocolloid impression
material in stock trays, as a preextraction record for determining
the original vertical position of the mandibular anterior teeth.

REFERENCES
 Sheldon Winkler.: Essentials of complete denture Prosthodontics, ed. 2,
2004.
 zarb-bolender : Prosthodontic treatment for edentulous patients - ed 12.
2004.
 Heartwell :Textbook of complete dentures – ed 5.
 David M. Watt and A. Roy Macgreggor : Designing complete dentures –
ed 2 . 1986.
 D.J. Neill and R. I. Nairn : Complete denture prosthetics-, ed 3. 1990
 Iwao Hayakawa : Principles and practices of complete dentures- creating
the mental image of a denture.
 Alexander R. Halperin :Mastering the art of complete dentures .

4. J P Frush, R Fisher. How dentogenic restorations interpret the sex
factor. J.Prosthet Dent 1956;6:160-172
5. J P Frush, R Fisher. How dentogenics interprets the personality
factor. J.Prosthet Dent 1956;6:441-449
6. J P Frush, R Fisher. Age factor in dentogenics. J.Prosthet Dent
1957;7:05-13
7. Harold R. Ortman and Ding H. Tsao. Relationship of the incisive
papilla to the maxillary central incisors. J Prosthet Dent. 1979; 42;
492-496
8. B.K. Goyal and K.Bhargava, Arrangement of artificial teeth in
abnormal jaw relations: maxillary protrusion and wider upper arch. J
Prosthet Dent. 1974; 32; 107-111
9. B.K. Goyal and K.Bhargava Arrangement of artificial teeth in
abnormal jaw relations: mandibular protrusion and wider lower arch.
J Prosthet Dent. 1974; 32; 458- 461.

10. Curtis M. Becker,Charles C. Swoope, Lingualised occlusion
for removable prosthodontics. J Prosthet Dent. 1977; 38; 601-
608.
11. Arthur R. Roraff, arranging artificial teeth to anatomic
landmarks. J Prosthet Dent. 1977; 38; 120 - 130.

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