6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients.

Prof. Amal Fathy Kaddah
Dr. Mohamaed Kandel
Department of Prosthodontics,
Faculty of Dentistry, Cairo University.
Dr. Marwa Anas El-Wegoud
Dr. Mohamed Adel
Dr. Mohamed Esawi
Dr. Ramy kalaifa
Dr. Mariam Roshdy
Dr. Heba Salama
Dr. Samah Ahmed
Dr. Abobakir abasho

When you realize you've made a mistake,
take immediate steps to correct it.

Contents:
I-Introduction
II-Factors affecting teeth arrangement
1. Pattern of bone resorption
2. Esthetics and phonetics requirements.
3. Stability
4. Occlusal plane
5. Arch form ( Arrangement of teeth in harmony with ridge contour)
6. Interdigitation of the teeth
7. The inclination for proper occlusion
8. Arch relationship
III- Guidelines governing the position of artificial teeth
IV- Arrangement of teeth in normal cases.
V - Atypical arrangement of teeth (Class II, Class II)
VI- Common errors in teeth setting.
VII- Occlusal Schemes- Attempts to Stabilize Dentures (Lingualized and Monoplane occlusion).

Guidelines for arrangement of teeth
A- Key of occlusion
a.Canine key of occlusion
b.Molar key of occlusion
B- Anatomical landmarks
C- The normal Overjet & overbite

Identifying the problem
Through:
1) Clinical examination Extra-
oral & intra-oral
2) Diagnostic bite record and
mounting on articulators
3) Radiographic analysis

Introduction
 According to the relation between the bones of the
face and the jaws, facial skeletal pattern is classified
into:
Angle’s classification of the facial skeletal pattern

Introduction
 The selection of teeth for edentulous patients requires a
knowledge and understanding of some physical, biological
and mechanical factors.
 Any choice of artificial teeth must be considered as a
preliminary selection until the teeth are arranged on trial
denture bases and viewed in the patient’s mouth.
 The teeth are not only an important component of facial
appeal, they give each face a unique identity and make it
easily recognized ( Important factor for denture success ).

NORMAL OCCLUSION
The mesial incline of the maxillary canine occludes with the distal incline
of the mandibular canine. The distal incline of the maxillary canine
occludes with the mesial incline of the mandibular first premolar.
Normal Line of Occlusion, normal smooth curves. normal overbite and
overjet and coincident maxillary and mandibular midlines.
Molar Relationship:
According to Angle, the mesiobuccal cusp of
the maxillary first molar aligns with the buccal
groove of the mandibular first molar.
Canine Relationship: The maxillary canine
occludes with the distal half of the mandibular
canine and the mesial half of the mandibular
first premolar.

Class I Malocclusion
Molar Relationship and Canine Relationship as normal occlusion, but
Line of Occlusion: ALTERED in the maxillary and mandibular arches
Individual tooth irregularities (crowding/spacing/other localized tooth
problems).
Inter-arch problems (open bite/ deep bite/cross bite).
Mesognathic: normal, straight face profile with flat facial appearance.

Class II malocclusion
• Canine Relationship: The mesial incline of the maxillary canine occludes
ANTERIORLY with the distal incline of the mandibular canine. The distal
surface of the mandibular canine is POSTERIOR to the mesial surface of
the maxillary canine by at least the width of a premolar.
• Molar relationship: The molar relationship shows
the mesiobuccal groove of the mandibular first
molar is DISTALLY (posteriorly) positioned when
in occlusion with the mesiobuccal cusp of the
maxillary first molar.
• Usually the mesiobuccal cusp of maxillary first
molar rests in between the first mandibular molar
and second premolar.

CLASS II DIVISION 2
Condition when class II molar
relationship is present with
retroclined upper central
incisors, upper lateral incisors
may be proclined or normally
inclined.
Overjet is usually minimal.
CLASS II DIVISION 1
Condition when class II
molar relationship is
present with proclined
upper central incisors.
There is an increase in
overjet.
CLASS II SUB-DIVISION
Condition when the
class II molar
relationship exists
on only one side with
normal molar
relationship on the
other side.

1. TRUE class III malocclusion (SKELETAL) which is genetic
in origin due to excessively large mandible or smaller than
normal maxilla. The mesiobuccal cusp of the lower fist
molar occludes mesial to the class I position
Class III malocclusion
has 3 subdivisions:

(Forward movement of the mandible during jaw closure can
also result from premature loss of deciduous posterior
teeth.
2- PSEUDO Class III malocclusion
(FALSE or postural) which occurs
when mandible shifts anteriorly
during final stages of closure due
to premature contact of incisors or
the canines. It’s also known as
postural class III.

3- Class III Sub-division:
• Class III molar relationship exists on one side and
the other side as a normal Class I molar relationship.

Certain rules and principles
that should be followed
during managing complete
denture cases

1. In the cases with abnormal arch relationships, The
relationship cannot be changed by setting up the teeth,
and any attempt to make the occlusion normal in
abnormal arch relationships would compromise
esthetics, phonetics and function.
2. In the cases with abnormal arch relationships,
treatment should be restored in the Centric relation.
 Positions other than centric relation are not repeatable
 However, some modifications during setting-up are
necessary.

3. Mandibular posterior denture teeth must be placed
over the lower residual ridge, and adjustments
made with the maxillary occlusal table.
The horizontal
relations to the
residual ridges
The vertical positions
of the occlusal surfaces
and incisal edges
between the residual
ridges

4. Freedom of movement is a must during eccentric
movements.
5. Multiple occlusal contacts must be established
in centric and eccentric positions whatever the
occlusal scheme used. (with the use of Anatomic
Teeth, a Steep Occlusal Plane, a More
Pronounced Curve Of Spee, and with monoplane
teeth use of a Balancing Ramp which is
necessary for protrusive balance).

6. Whether the relation is class I,II
or III, when setting up dentures,
the upper and lower first molars
must have the same relationship
to each other as in an Angle
class I.
i.e.: Upper mesio-buccal cusp of first molar has contact between
the lower mesial buccal and buccal cusp of first molar.
Note: in class III, reverse cusp fossa relationship could be done.

 In the maxilla: After extraction of the teeth resorption
of bone occurs vertically, labially and buccally, so it
becomes small in size.
 In the mandible: bone resorption occurs vertically and
lingually, so it becomes wide.
 By understanding this pattern setting of the anterior
teeth should be inclined labial to the crest of the ridge
to restore the natural position of the anterior teeth.
Factors affecting setting of teeth
1- Pattern of bone resorption

2- Esthetics and phonetics:
 Labial surface of teeth should support the lips.
 It's important to produce pleasant appearance and
to simulate the natural teeth to a great extent.

3- Role of The occlusal plane on Esthetics,
phonetics and stability:
a. Anterior teeth should be 2mm below the upper lip.
b. In flat lower ridges, occlusal plane should be as
close as possible to the ridge.

c. The horizontal relations
to the residual ridges
d. The vertical positions of
the occlusal surfaces and
incisal edges between
the residual ridges

Factors must be considered:
1- Aesthetic base
2- Functional base
(chewing and speech)
3- Physical and mechanical
(leverage action and parallelism)

It is the ability of a denture to be firm,
steady or constant, by functional stresses
and not to be subjected to change of
position when forces are applied.
It is the ability of a denture to resist
displacement by functional stresses.
4- Stability:

 If the teeth are placed too far forward, they will
displace the denture due to active lip muscles.
 If they are placed too lingualy, they can cause
tongue crowding which also results in denture
displacement during tongue movement.
 If placed too far buccally, the action of the
buccinator muscles can dislodge the denture
too.

 The level of the occlusal plan should be
below the level of the maximum convexity
of the tongue to provide denture stability

VD CO # CR
Uneven
pressure
Cuspal
interference
Teeth off ridge
Tuberosity of
opposite side
In upper buccal
sulcus of working
side
White sore
area on the
site of
pressure
VD
(Neurological
pain)
VD (white
patch)

5- Interdigitation of teeth
 Maximum interdigitation should
be achieved.
 The upper and lower teeth
should be set to have a definite
cuspal relation to each other, in
order to maintain both positional
and functional relationship.

The maxillary arch:
U-shaped form.
While
The mandibular arch:
V-shaped form.
6- Arch form:

The arch form can be:
 Square Arch:
Central incisors are in
line with canines.
 Tapering Arch:
Central incisors are at
a greater distance
forward than canines.
 Ovoid Arch:
In between

 According to the relation between the bones of the
face and the jaws, facial skeletal pattern is classified
into class I, II and II arch relationship:
7- Jaw relationship
Animation

Factors governing the position
of artificial teeth
I- Key of occlusion
1. Canine key of occlusion
2. Molar key of occlusion
II- Anatomical landmarks
III- The normal Overjet & overbite

I-Key of occlusion:
It denotes the relationship
of upper and lower teeth
during function.
1- Canine relationship:
The mesial incline of the upper canine aligns
with the distal incline of lower canine

2- Molar relationship:
 The mesiobuccal cusp of maxillary
first molar should aligns with the
mesiobuccal groove of mandibular
first molar.
 The mesiolingual cusp tip of
mandibular first molar should fit
into the central fossa of the upper
first molar.

II. Anatomical Landmarks
1) Midline
2) The canine lines
3) Incisive papilla as a guide
4) High Lip Line
5) Interpupillary line
6) Ala- Tragus line
7) Retromolar pad
8)The maxillary tuberosity.

1) Midline:
A line drawn anteroposteriorly bisecting
the midsagittal suture, incisive papilla and
labial frenum coincide with the midline of
upper dental arch.
• Nose – Distance between tips of canine is
same as width of base of nose
• A vertical line extending along the lateral
surface of the ala often will pass through
the middle of the natural upper canine.
• Philtrum – Width of upper centrals, approximates
the width of philtrum

2) 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.
Widest part of nose (interalar
width), Distance between canine
cusp tips (intercanine distance)

The incisive papilla is situated on a
transverse line passing through
the tips of the canines in the
dentate person.
3) Incisive papilla as a guide

 The incisive papilla is a
valuable guide for anterior
teeth placement because
it has a constant
relationship to the natural
central incisors.
The labial surfaces of upper central incisors are
8-10 mm anterior (in front) of the middle of to
the incisive papilla.

The anteroposterior positioning of
anterior teeth is important for
esthetics and phonetics, because of
the support that is provided to the
lips and cheeks from the teeth.
Therefore, anterior artificial teeth should be placed in the
same position or as close as possible to that occupied by
the natural teeth to maintain natural patient appearance.
Inner edge of the land
When viewed from profile or sagittal,

Inner edge of the land
When viewed from profile or sagittal,
• The tooth has a slight labial
inclination to give support to the
upper lip, the neck is slightly
depressed (the incisal edge is
more prominent than the cervical
area of the tooth), and the facial surface of the
tooth is nearly perpendicular to the occlusal
plane.

4- High Lip Line
• Highest point of upper lip when
smiling, determines the length
of the teeth.
• Cervical necks lie at or above
this line (according to lip length
and level of retromolar pad).
• If shorter teeth are existing,
esthetic is compromised.

High lip line
Low lip line
Amount of teeth showing

Variation of Appearance with Different Dentures

5) Interpupillary line:
The occlusal plane of maxillary
anterior teeth should be parallel
to the interpupillary line.
The posterior occlusal plane
should be parallel to the ala-
tragus line (from the ala of the
nose to the tragus of the ear).
6) Ala- Tragus line

7) Retromolar Pad:
• It is a fixed anatomic landmark used most
frequently as a reference or a guideline for teeth
arrangement as in three dimensions:
Anteroposteriorly, vertically and laterally.

• Anteroposteriorly, no artificial
teeth are placed posterior to the
anterior boundary of the pad, to
avoid having a tooth over an incline
which results in denture sliding.
• Vertically The posterior occlusal
plane should be at the level of 2/3
the height of retromolar pad.
Fixed Position
Measurable
Identifiable
Relationship to natural dentition
Mesiodistal Width
available.
7) Retromolar Pad:
Incorrect

Aligned Occlusal Groove
The occlusal groove of the
posterior teeth should lie on
the straight line joining the
distal arm or the tip of the
canine anteriorly and the
midpoint of the occlusal
rim posteriorly.
• Laterally

The posterior teeth are generally
placed to enhance the stability of
the mandibular denture.
 The mandibular teeth should be
arranged so that they are positioned
over the crest of mandibular
residual ridge.
The Retro molar pad is used as a guideline
to determine the buccolingual position.

Not to encroach on tongue space and
buccal corridor.

8)The maxillary tuberosity
•It lies immediately posterior
to the maxillary second molar.
•Teeth should not be set on
the tuberosity as it can lead
to lever imbalance and cheek
biting in posterior region.
Correct
Incorrect

Buccolingual Width
• Sufficient to act as a table
to hold food.
• Less than width of natural
teeth.
• Limits forces directed to ridge.

Determined by available inter ridge space,
occlusal plane and height of anterior teeth.
Occluso-gingival Height

III- Overjet and overbite:
The overjet is measured in horizontal plane while the
overbite represents the vertical plane.
 Normal overjet should be: 1.5 mm.
 Normal overbite should be: 0.5 mm.

The horizontal overlap between
upper and lower anterior teeth is
automatically decided by the
relation between the upper and
lower residual ridges.
The upper and lower anterior
teeth shouldn't be in contact
in centric occlusion.

• The middle of the crest of the
mandibular ridge should be recorded.
• Mark the midline of the patient’s face
by placing a dot on the incisive
papilla and marking this midline on
the maxillary anterior land area,
extending down the front of the cast.
The incisive papilla is a much more
reliable landmark for the midline than
the labial frenum.

1. Arranging the maxillary anterior teeth
a. Maxillary central incisors
*In frontal plane: The long axis of
the tooth should incline slightly
distally.
• The incisal edge should touch the
mandibular occlusion rim.
• The contact point should
coincide with the midline of the
face.

*In horizontal plane: The facial surface of the
central incisors should be 8-10 anterior to
the center of the incisive papilla.
*In sagittal plane The neck is slightly
depressed.

b. Maxillary lateral incisors
(Incisal edges of central incisors & canines
at level of the occlusal plane.)
3. Laterals placed approximately
0.5 to 1 mm above the occlusal
plane.
1.In frontal plane, the long axis should
inclined slightly distally (5-10 degree to the
midline)
2. The neck is more depressed.

*In sagittal plane, it shows slight labial
inclination, its neck is depressed more than
the Central incisor.
*In horizontal plane, it must follow the arch
curvature.

• The canine tooth is an important
tooth in tooth arrangement because,
it forms the corner of dental arch.
* In frontal plane the cuspid has a
slight distal inclination more than
other teeth and the incisal tip touches
the occlusal plane.
• Distal aspect of the canine should
coincide with the crest of the ridge.
c. Maxillary Canines

*In sagittal plane, is perpendicular to the
occlusal plane, the incisal tip of the canine
touches the occlusal plane. with a more prominent
cervical neck & supports the corner of patient's
the mouth.

* In horizontal plane When viewed from the occlusal the
anterior teeth follow the curvature of the dental arch.
Canine is rotated with arch and represents the corner or
turning point of upper arch.

The cuspid has two planes on the labial surface – a mesial plane
(yellow line) and a distal plane (red line). When viewed from
the anterior only the mesial plane should be visible. the mesial
plane should follow the contour of the anterior teeth while the
distal plane follow the contour of the posterior teeth.

Incisal views of anterior teeth showing their angle of rotation.
Central & lateral incisors must begin to turn along
the curvature of the arch

Bucco-Lingual Tilt
• Facial surface of central is perpendicular
on occlusal plane or slightly inclined
labially
• Neck of lateral is depressed
• Neck of canine is prominent.
Central Canine
Relations and inclinations of maxillary anterior teeth.
*In sagittal plane:
Remember

The greatest height of
the free gingival
margin is slightly distal
to the mesiodistal
center of the tooth

Width of max. Centrals = width of philtrum
Low L L
High L L

• Make a cut with a heated, sharp knife, at the midline
in the anterior wax rim. Cut all the way to the
baseplate. Make a similar cut just distal to the canine
point. Remove this section of wax in its entirety.
Procedures for arranging the maxillary anterior teeth

• Use a flat plate to position the central incisor so
that it contacts the occlusal plane.
• Set the rest of the anterior teeth on the right side
according to the curve defined by (occlusal rim).

N.B. Anterior teeth are set to follow the arch
form of the patient's residual ridges. The
incisal edges of the anterior teeth should be set
to correspond to the shape of the arch.

• Use a flexible plastic ruler to verify that the
incisal portion of the tooth’s labial surface is
properly located and in contact with the anterior
curvature of the occlusion rim.

• An anterior view of the maxillary anterior
teeth shows that only the lateral incisors do
not touch the occlusal plane as recorded by
mandibular wax rim.

Lower central incisor
2. Arranging the mandibular anterior teeth
Vertical
overlap
Horizontal
overlap
*In frontal plane, the midline of lower C.I should
be coincide with the midline of upper C.I.
• Long axis should be set perpendicular to the
occlusal plane.
• The neck of tooth should be slightly depressed.
• The incisal edge should form (1-2mm) horizontal
and vertical overlap in respect with upper central
incisor.
* In sagittal plane: The lower central incisor has slight labial
inclination & its neck is depressed.

The incisal guidance angle is the angle formed by a line
drawn through the incisal edges of the maxillary and mandibular
incisors and the horizontal plane.
It is generally advisable to keep the incisal angle to a minimum
in complete dentures to enhance free movement of the teeth in
protrusive and lateral excursions so that about 0.5 : 2 mm. over bite
& 2-4 mm. Horizontal overlap.
.5 -2 mm
2 -4 mm

Lower lateral incisors:
*The lateral incisors should be placed similar in
position to the central incisors.
• Long axis slightly inclined mesially and the occlusal
height should be the same as the central incisors.

• The long axis of the cuspids
is slightly inclined mesially.
• The neck is more prominent
than the tip.
• The cusp tip 2mm above the
occlusal plane.
Lower canines:

• The tip of lower canine will be in the embrasure
between upper lateral incisor and upper canine &
its distal slope should be opposed to the mesial
slope of upper canine, it's called normal canine
position.

The horizontal overlap should be
consistent throughout the anterior region.
At this stage it should be about 1.5 mm.

• Mark the midline of the mandibular ridge on the mandibular
wax rim and cut out a section representing the right
mandibular anterior teeth from the rim.
• Arrange the lower anterior teeth following the arch shape
• Position the teeth over the crest of the ridge.
Procedures for arranging the mandibular anterior teeth

Set the mandibular central incisors so that the
maxillary incisors cover them from .5: 2 mm
vertically and 2: 4 mm horizontally if you are
using anatomic posterior teeth.

3- Arranging the maxillary posterior teeth
Maxillary first premolar
The facial surface of maxillary 1st
premolar must harmonies with canine.
Long axis of tooth perpendicular to the
occlusal plane.
Buccal and palatal cusps touch the occlusal plane.
Palatal cusp over crest of mandibular ridge (contact the line
inscribed on the lower occlusion rim indicating the crest of
the lower residual ridge).

Maxillary second premolar
• Long axis of tooth perpendicular to the occlusal
plane.
• Both Palatal and buccal cusp tips contact the plane
of occlusion.
• Palatal cusp over crest of mandibular ridge.
Buccal
Palatal

Maxillary first molar
• Mesio-palatal cusp touch the occlusal plane.
• The facial surface: 1st molar must harmonies with
1st and 2nd premolar.
• The disto-buccal cusp is raised about 1/2 mm and
the disto-Palatal cusp is raised about 1/2 to 3/4 mm
above the occlusal plane.

• Note that the mesiopalatal cusp tip touches the plane of
occlusion along with the buccal and lingual cusps of the
premolars while the buccal cusps tips and the distolingual
cusp tip are elevated about 0.5mm of the occlusal plane.
The curve of Spee begins at the 1st molar.
Profile view

• Set the teeth so that the buccal surfaces of the premolar(s) and mesial cusp
of the first molar line up with the mid-buccal surface of the canine.
• The distobuccal cusp of the first molar should deviate approximately 20o
from this plane and the second molar will fall along this plane.
• Set the teeth on the maxillary right side so that the mesiolingual cusp of the
maxillary first molar rests in the central fossa of the mandibular first molar.

Maxillary second molar
• All four cusps are above the occlusal plane
• The facial surface of 2nd molar must harmonies with
1st molar
• Cusps of the second molar are raised from the occlusal
plane following the position of the first molar.
Distal
Mesial

Relation of buccal surfaces of
premolars and molars with the buccal
surface of the canine

*Compensating curve
• Is the anterio-posterior curvature of the occlusal surface of a
complete denture teeth (in sagittal plane) and the
mediolateral curvature in the frontal plane. The compensating
curves are called so because they compensate for that
present in natural dentation. Compensating curves may be
increased or decreased in an artificial dentition to help
achievement of balanced occlusion.

Curve of Spee
Is the curvature of the occlusal
alignment of the teeth. It begins at the
tip of the lower canine follows the
buccal cusps of the premolars and
molars and continues to the anterior
border of the mandibular ramus.
Is the curvature in the frontal plane
through the cusp tips of both the right
and left molars.
Curve of Wilson

• The compensatory curve of Wilson and the curve of Spee
begin in the molar region. The mesial lingual cusp tip of the
1st molar contacts the occlusal plane but the buccal cusp tips
and the distal lingual cusp are elevated about .5 mm off the
occlusal plane.
*Compensating curve
Upper first molar

The compensatory curve is continued by elevating the
2nd molar above the plane of occlusion.
The 2nd molar is elevated to an even greater degree
than the 1st molar, about 15 degrees in the average
patient, with a slight curve of Wilson.

Relation of maxillary posterior teeth to occlusal plane.
Procedures for arranging the maxillary posterior teeth
• Remove the wax on one side of the maxillary baseplate.
• The rim is left intact on the opposite side because this
will help you to maintain the location of the occlusal
plane as explained before.

• Set the teeth so that the buccal surfaces of the
premolar(s) and mesial cusp of the first molar
line up with the mid-buccal surface of the canine.
Fig. 1
Relation of buccal surfaces with the canine.
1
2 3

• The distobuccal cusp of the first molar should
deviate approximately 20o from this plane and
the second molar will fall along this plane. Fig.
2, 3
1
2 3

• Set the teeth on the maxillary right side so
that the mesiolingual cusp of the maxillary
first molar rests in the central fossa of the
mandibular first molar.
The mesiolingual cusp of the maxillary
first molar rests in the central fossa of
the mandibular first molar

• In which, their central fossa must
coincide or placed over the crest of the
lower residual ridge.
3- Arranging the mandibular posterior teeth

In centric occlusion, the disto-buccal cusps of the
mandibular teeth fit into the central fossae of the
maxillary teeth while the lingual cusps of the maxillary
teeth fit into the central fossae of the mandibular teeth.
This position establishes the proper buccal overjet.
Section through the molar region of full maxillary and mandibular dentures.

• Mesiobuccal cusp of the lower 1st molar
occludes in the fossa between upper 2nd
premolar and 1st molar.
Mandibular First Molar
• Long axis of tooth perpendicular
to the occlusal plane.
• Buccal and palatal cusps above
the occlusal plane.

Mandibular First Molar
• Check the relationship from
the lingual side.
• Make sure that the maxillary
lingual cusp tips engage the
central fossa of the
mandibular molar.

Mandibular Second Premolar
• Buccal and palatal cusps above
the occlusal plane.
• Its buccal cusp should occlude with the adjacent
marginal ridges of the maxillary 1st and 2nd
premolars (the fossa between two upper
premolars).

• Its buccal cusp should engage
the mesial marginal ridge of the
opposing 1st premolar.
Mandibular first premolar
• Buccal cusp above the occlusal
plane.
• Lingual cusp is below the
occlusal plane.

• Make sure that the lingual cusp
of the maxillary second molar
properly occludes with the
central fossa of the mandibular
second molar.
Mandibular second molar
• Mesiobuccal cusp of the lower 2nd
molar occludes in the fossa
between upper 1st and 2nd molars.

Procedures for arranging the mandibular posterior teeth
 With a pencil, use a ruler to mark the
crest of the mandibular ridge from the
base of the retromolar pad to the canine
area. This will identify the crest of the
mandibular ridge (B)
 Extend the previous markings onto the
wax rim to serve as a guide when
arranging the teeth.
 Line extend from canine tip and center of
retromolar pad.

 Enough wax is removed opposite the
maxillary second premolar and first
molar to allow setting of the posterior
teeth.
 Mandibular first molar intercuspating
with the maxillary second premolar and
maxillary first molar.
 Mandibular second molar intercuspating
with the maxillary first and second
molar.

 Check the position of the teeth
over the crest of the ridge.
 Mandibular first premolar
intercuspating with maxillary
first premolar and canine.
Central grooves in line with canine
tip and center of retromolar pad.

N. B.
• Incisal pin should touch the
incisal table throughout the
whole work.
• If there is no space for the
mandibular first premolar, it
is advisable to grind it.

Problems and possible
solutions

Problem >> Convex face
profile resulting from a
mandible that is too
small or maxilla that is
too large.
Class II

• Distobuccal cusp of maxillary first
molar falls on the mesio-buccal
groove of mandibular first
permanent molar.
It is divided into:
Class II Div 1: Upper incisors are proclined
Class II Div 2: Upper laterals overlap centrals and the
centrals are retroclined
Class II

Prosthodontics' problems in angle class II
Problem in static relationship and functional
Relationship.
Functional
-Anterior Posteriorly

1. Lower ridge is narrower than the upper
and associated with a receding chin.
2. Setting the upper teeth inside the ridge
and lower teeth outside the ridge does
not produce marked stability
3. Large overjet is preserved. Angulations of the upper teeth
give the patient a rabbit appearance .
Angulations of the lower tend to unstabilize the denture
Prosthodontics' problems in angle class II

In a normal bite (class I) the upper
cuspid is positioned posterior to the
lower cuspid.
In a (class II) deep bite a reverse cuspid
relationship due to a strong overjet.
Class II Cuspid relationship.

1.Modifications Done in Setting Up of Teeth for
Angle Class II
1.Modifications Done in Posterior Teeth
Morphology:
SR Orthotype Teeth

Modifications Done In Setting Up of Teeth for Angle Class II
Anterior teeth arrangement
1- Vertical overlap should be kept as
minimal as the esthetics and phonetics
permit.
2-Maxillary anteriors are set-up with their incisal edges inclined
more palatal than their necks.
3- Labial inclination of lower anteriors.
4- Leave out a lower central or lateral incisor, or overlap lower
teeth.

5. When retrusion is not extreme.
 Narrower lower anteriors.
 Slight spaces between the upper anterior teeth or,
 Slight crowding of lower anterior teeth.
Modifications Done In Setting Up of Teeth for Angle Class II

6. When it is too great and can not be by modification
of anterior teeth >> Remove lower first bicuspid
In case, the lower first bicuspid was dropped in order to
achieve a correct posterior relationship.

Angle’s Class II division 2 :
If the overbite and minimal overjet
of these cases is reproduced in an
artificial tooth set-up, the patient
could be locked into an impossible
situation. So there needs to be some
re-positioning of the teeth to reduce
the overbite as much as possible
without overly compromising
aesthetics.

Slight labial inclination of lower anteriors + Slight lingual
inclination of upper anteriors
Slight spacing of upper anteriors or Slight crowding of
lower anteriors.

 The incisal edge of the upper anteriors should
point toward the lower mucolabial fold.
Set up the upper posteriors starting with the first molar to
ensure correct occlusion in order to achieve popper occlusal
contacts and balancing movements the molars have to be in
a normal occlusal relationship to one another
 Starting the upper posterior set- up with the first
molar.

Posterior teeth arrangement
1. Non-anatomic teeth or teeth with
shallow inclines are selected to
reduce the stress on the weaker
lower ridge.
2. Eliminate lower 4
3. Upper posterior teeth can be
placed slightly palatal to provide a
working occlusal contact with the
lower teeth.

4. The lower posterior teeth are placed over crest of
the ridge. The upper teeth are then set so that they
occlude with the lower teeth
5. Upper palatal cusp ...........
‫؟؟؟‬
............ (lingualized
occlusion)
6. A combination of lever balance and occlusal
balance is possible by incorporating both a buccal
tilt and a lingual tilt in the posterior arrangement.

If the upper arch is much wider than lower arch :
- Set the lower first on the ridge
- Set the upper and lower separately

• A further complication arises in those cases
where the upper arch is much wider than the
lower. In these cases, the lower teeth are first
set in their most appropriate positions relative
to the lower arch.
• The uppers are then set in their most appropriate
positions for aesthetics.
• If then it is found that the uppers and lowers don’t meet, a
further line of teeth can be placed palatal to the uppers, or
the base can be waxed to the lowers and replaced with
tooth-colored resin.

Occlusal scheme
The problem is that the patient functions in a variety
of positions anterior to centric relation position, and
providing for protrusive balance is very difficult with
cusped teeth.
With a lingualised concept, however, the occlusal
tables of each tooth can be successively recruited to
maintain contact during protrusion, and a long
anteroposterior area of contact can be obtained. This
is done by placing the lower teeth on an appropriate
compensating curve and then adjusting the occlusal
tables for all protrusive movements.
- Lingualized and Monoplane occlusion

Problem >>
Concave face profile with
prominent mandible is
associated with Class III
malocclusion.
Angle class III

Problems associated with class III cases
1. The relation between the ridges may vary from
edge to edge relationship to extreme
prognathism of the lower arch.
2. Wider lower arch leads to problems in selecting
the size of the teeth as selecting the same mold
size for both arches leads to spacing between
lower anterior teeth which reduce aesthetics.
3. The Crest of the lower arch is located further buccally than that of the
upper one, leading to problems in obtaining an adequate occlusal
relation between upper and lower teeth.

Class III – Cross Bite
There are different types of cross bites:
1. Unilateral cross bite.
2. Bilateral cross bite( due to maxillary atrophy, the lower arch is larger the upper
arch. Cross bite begins usually at the 2nd premolar.)
3. Bilateral cross bite including an anterior cross bite (rare: overdevelopment of the
lower arch in comparison with the upper).

Anterior teeth arrangement:
1. Edge to edge relationship
2. Inclining the mandibular anteriors lingually
as possible without encroaching the
tongue space.
Modifications done in setting up of teeth for angle Class III
3. Inclining the maxillary anteriors more
anterior to the crest of the ridge than usual,
with their incisal edges being inclined more
labial than their necks.

Slight crowding of upper anteriors
4. Addition of lower lateral or central incisor
5. Wider lower anteriors.
6. Slight crowding in upper anteriors.

3. Cross-bite is accomplished to avoid unfavorable
leverage that compromises denture stability
4. Larger sized upper posteriors + Medium sized
lower posteriors.
5. In case of wider lower arch, an interchange can be done by
using upper teeth on the lower denture and lower teeth on the
upper denture.
Posterior teeth arrangement:
1. Monoplane posterior teeth or cuspless teeth (preferred)
2. Upper posterior teeth can be placed slightly buccal
to the crest of the upper ridge.

Lingualized articulation
• “An occlusion for all reasons” There is hardly a clinical situation where
it is not applicable and the adjustments, especially at the chairside.
• This scheme use cusped upper teeth 30_ or 33_ cuspal angles, modified
to ensure that the buccal cusps take no part in the articulation. The
lower teeth use 20_ or 0_ teeth,
• Occlusal surfaces are in harmony with the angles of the upper palatal
cusps.
• The main problem with posterior tooth placement in these cases, is that
of a medio-lateral arch discrepancy and the need for a cross-bite
arrangement.
• In this case, the lingualized concept becomes a “Buccalized” one.

Cross-bite is accomplished to avoid unfavorable
leverage that compromises denture stability.
Buccalized occlusion:

2. Modifications done in posterior teeth morphology:
SR Orthotyp Teeth
 It was Designed by Dr. R Strack in the 1950’s and
manufactured by Ivoclar Vivadent.
His morphology recognizes the three bite classifications:
Class I (normal bite –N mould)
Class II (deep bite- T mould) and
Class III (cross bite – K mould).
 They differ in the cusp angulations and the guiding surfaces.

• Failure to make the canine the turning point of the arch
• Setting mandibular 1st premolar to the buccal side of the
canines.
• Setting the mandibular posterior teeth too far to the lingual
side in the 2nd molar region which cause tongue interference
and mandibular denture displacement.
• Failure to establish the occlusal plane at the proper level and
inclination.
• Establishing the occlusal plane by an arbitrary line on the face.
Common errors in arrangement of teeth

Buccal Corridor
• Space between buccal Surface of
posterior teeth and inner surface of
cheeks.
• Excessive Buccal Corridor results when
posterior teeth are set too far lingually.
• Resulting dark space appears excessive
and unaesthetic.
• Inadequate Buccal Corridor occurs
when posterior teeth are set too far
buccally, causing obliteration of the
buccal corridor.

Surgical correction of severe discrepancy
In case of severe jaw size discrepancy,
surgical correction may be a successful
alternative for routine prosthetic work.
In many cases this choice may be refused
due to systemic disease or patient
aware.
Ridge osteotomy is considered a major
surgery usually done under general
anesthesia so benefits must be weighted
against harms.
Bimaxillary Osteotomy in a Young Edentulous Patient

Occlusal Schemes
Attempts to Stabilize Dentures

Occlusal Schemes
Attempts to Stabilize Dentures
• Lingualized Occlusion: Contacts
on centered on mandibular ridge
minimizes movement.
• Monoplane Occlusion:
Lack of cusps minimizes lateral
forces on denture

Balanced Non- Balanced
– Maxillary anatomic (33°)
– Mandibular Teeth
 Non-anatomic
(Portrait 0°)
If Shallow Condylar
Guidance
If Steep Condylar
Guidance
– Maxillary anatomic (33°)
– Mandibular Teeth
 Shallow Cusped
(Anatoline)
The Lingualized Occlusion

Set mandibular premolars &
1st molar:
• Level with occlusal plane
•Centered over ridge
Line indicating the crest of the ridge
The Lingualised Occlusion
Occlusal plane
RULES

Lingualized Occlusion
• Anatomic teeth used in maxilla
– Better esthetics than Monoplane
• Shallow cusped mandibular teeth
– Forces centered over mandibular
ridge
Line indicating the
crest of the ridge

•Lingual bone resorption prevents
placing teeth within the neutral zone
•Maintaining teeth on the ridge
preserves lever balance
•Lingualized occlusion helps
centralization of force.
Bone
resorption
Neutral
zone

A method to achieve bilateral balanced
occlusion with an attempt to maintain
the esthetic and food penetration
advantages of the maxillary anatomic
form while maintaining the mechanical
freedom of the mandibular semi-
anatomic and non- anatomic form.
The Balanced Lingualised Occlusion

Max. lingual cusps
contact central
fossae/marginal ridge
~ 1mm space between
buccal cusps
No max. buccal cusp contacts

Centric Position
• In centric- simultaneous bilateral posterior contacts
(maxillary lingual cusp)
• No overbite

Anterior teeth
are in contact
during lateral
excursions
Working Excursions
Balancing Excursions
In lateral excursive movements clearance between the maxillary and
mandibular buccal cusps to increase lever stability to the lower denture.
Bilateral Eccentric Equilibration

Basic Tooth Positions
Balancing Contacts Centric Occlusion
Ideally all holding cusps of the maxillary and mandibular posterior teeth will make
simultaneous contacts.
The Lingualised Occlusion
Balancing Contacts Centric Occlusion
Working Contacts
1:2 mm
Working Contacts

• May or may not have balancing contacts in
excursions
• Anterior teeth - must make at least grazing contacts
in excursions
Second molar elevated by ~ 15° from the occlusal plane
15
degrees

Non-Balanced
Maxillary anatomic opposing mandibular non-anatomic
Mortar & pestle occlusion
without maxillary buccal cusp
contact.

Lack of mandibular cusp angles and no attempt to
balance the occlusion
No compensating curves
No overbite

Setting the posterior teeth
• Teeth should end prior to the
ascending ramus
• Mandibular teeth set to a flat plane
and on the plane of occlusion.

• Maxillary lingual cusps contact
central groove/marginal ridge of the
opposing teeth.
• All maxillary teeth, with the
exception of the lateral incisors
should be on the plane of occlusion.
Beumer J, DDS, MS and Michael Hamada DDS: 16. Occlusal Schemes - Lingualized Occlusion Division of Advanced
Prosthodontics, Biomaterials and Hospital Dentistry UCLA School of Dentistry.

The horizontal
overlap should be
ideal and should be
sufficient to prevent
biting of the cheek
and corner of the
mouth.
Horizontal overlap
Beumer J, DDS, MS and Michael Hamada DDS: 16. Occlusal Schemes - Lingualized Occlusion Division of Advanced
Prosthodontics, Biomaterials and Hospital Dentistry UCLA School of Dentistry.

• Excursions - may or may not contact on
balancing sides.
• Depends on condylar inclination and
other aspects of the tooth arrangement.
• No overbite (would cause tilting)
• Overjet of 2 mm is used to create an
illusion of overbite.
Monoplane Occlusion

 Eliminate cusps: Flat occlusal surfaces against a
flat plane with 1.5-2.0 mm overjet:
 Lateral forces reduced
 Improves stability
 Simplifies tooth arrangement
 No cusp to fossa relationship
 No anterior contacts in centric position.
 Easily adjusted.
 Anterior teeth make contact in excursions
 To minimize the tilting potential:
 Balancing ramps
 Compensating curves
Monoplane Occlusion

Advantages
• Technically easier to achieve.
• Use when:
– Difficulty obtaining repeatable centric records (muscle incoordination)
– Skeletal malocclusion (Class II, III)
– Severe residual ridge resorption
– Reduces horizontal forces
Disadvantages
• Poorer appearance.
• Can be unstable if condylar guidance is steep (posterior teeth separate,
leaving only the anteriors in contact).
Monoplane Occlusion

Conclusion:
 Generally monoplane teeth are more adaptable for unusual jaw
relationships and permits the use of a simplified and less time
consuming technique
 Lingualised articulation is also recommended for the majority of cases
where it can easily solve most difficulties provided the principles of
balanced articulation .
 Multiple approaches deal with class II and class III edentulous
patients, any evidence based technique when followed precisely to the
right indicated patient will give successful result, but time must be
taken in diagnosing patient’s condition and deciding the correct
treatment plan.

References
1. Kaddah AF, and Libshtien IA. (1988)) Occlusion in Prosthodontics: Varieties, aberrations and
managements.
2. Applebaum M. (1984): Plans of occlusion. In: Dental Clinics of North America:
3. Becker CM, Swoope C and Guckes AD (1977): Lingualized occlusion for removable prosthodontics.
Journal of Prosthetic Dentistry 38:601-608.
4. Krishna Prasad D. et al. “Enhancing Stability : A Review of Various Occlusal Schemes in Complete
Denture Prosthesis” NUJHS Vol. 3, No.2, June 2013, ISSN 2249-7110.
5. Symposium on removable prosthodontics. p 273-285. W.B. Saunders, Philadelphia.
6. Occlusal considerations for partially or completely edentulous skeletal class II patients. Part I:
Background information, Thomas A. Curtis, D.D.S.
7. Occlusal considerations for partially or completely edentulous skeletal class II patients. Part II:
Treatment concepts Thomas A. Curtis, D.D.S.
8. A contemporary review of the factors involved in complete dentures. Part II: Stability. T. E. Jacobson,
D.D.S.
9. Principles And Practices Of Complete Dentures Creating The Mental Image Of A Denture -
Quintessence Pub; 1 edition (April 1999).
10. Ivoclar vivadent company.
11. Prosthetic Treatment of the Edentulous Patient - Wiley-Blackwell; 5th edition (25 Mar 2011).
12. Techniques in Complete Denture Technology - Wiley-Blackwell; 1 edition (April 23, 2012).
13. Textbook of Complete Denture Prosthodontics-Jaypee Brothers Medical Pub; 1 edition (December
30,2008).
14. Textbook of Prosthodontics - Jaypee Brothers; 1 edition (December 1, 2006).
15. Simple Method For Cross-bite Setup For Complete Dentures: A Case Report. Leonardo Marchini.
16. Arrangement of artificial teeth in abnormal jaw relations: Maxillary protrusion and wider upper arch -B.K. Goyal, B.D.S.

6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients.

6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients.

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to 6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients.

Similar to 6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients. (20)

More from AmalKaddah1

More from AmalKaddah1 (20)

Recently uploaded

Recently uploaded (20)

6- Prosthetic problems and possible solutions in setting –up of teeth for skeletal class I, II and class III arch relationship, for completely edentulous patients.