TEETH ARRANGEMENT
IN COMPLETE DENTURE
ARRANGMENT OF TEETH
The four 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
to provide stability to the denture bases.
to direct the masticatory forces along the long
axis.
to support lips and cheek for esthetics
to be compatible with functions of the
surrounding tissues for functions of masticaiton,
speech, swallowing and phonetics.
• Forces directed at right angles to the
supporting tissues are more stabilizing than
forces directed at an inclined plane.
• The artificial teeth must be placed in
suitable horizontal positions to allow the
muscle activity to occur naturally
• The positions of the teeth influence the phonetics
as exemplified by the J, ch, and sh sounds.
• When the maxillary anterior teeth are placed too
far posteriorly as related to the lower lip, the J
sound may be muffled.
• It may be necessary to arrange the mandibular
anterior teeth with more labial version to aid in the
correct pronunciation of the ch and sh sounds
• In mastication, the tip of the tongue reaches into the
buccal and labial vestibules, gathers the food, and places
it on the occlusal surfaces.
• When the teeth are placed too far in a lateral or anterior
direction, the vestibular spaces are obstructed to the
tongue.
• When the teeth are placed too far in a medial or posterior
direction, the tongue will dislodge the mandibular
denture in an attempt to reach over the teeth
The crests of the residual ridges are aids in
positioning the artificial teeth if the natural teeth
were recently extracted and the cortical plates of
bone remain intact. Unfortunately, the crests of the
residual ridges do not remain in the same
anteroposterior or mediolateral positions.
As resorption of alveolar
ridge progresses, the
maxillary arch becomes
narrower and the
mandibular arch becomes
broader.
• The upper lip is supported in the area of the
philtrum by labial surfaces of the maxillary
anterior teeth and at the corners of the mouth by
the canines.
• In normally related jaws, the border of the lower
lip is supported by the labial incisal third of the
maxillary anterior teeth.
•
•
•
•
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Definite anatomic landmarks
to be used as guides in
arranging the anterior teeth
are
the incisal papilla
the midsagittal suture, and
the canine lines.
By locating these
landmarks and recording
their positions on the cast,
one establishes points of
reference indispensable to
the correct arrangingof the
teeth
• In the absence of other more definite information, the
arch form is used as a guide for the initial arrangement
of the teeth
• The anterior teeth for the tapered arch places the central
incisors farther forward than the canines .
• The anterior teeth for the square arch places the central
incisors nearly horizontal with the canines.
• The anterior teeth for the ovoid arch places the six anterior
teeth in gentle curve.
A-SQUARE
, B- TAPERING, C- OVOID
VERTICAL POSITIONS
Correct vertical position of the teeth should
provideDenture stability
Favorable forces
Support to lips and cheek
Compatibility
Influences of age:
Muscle tone decreases with age, cheek saghorizontal overlap of posterior teeth increased to
prevent cheek biting.
Interincisal distance increases with age:
therefore more of the incisal portion of the
mandibular teeth is visible.
Teeth abrade with age. Central and lateral
incisor lie at same horizontal levels.
Smile of older individuals is more curved than
sharp as in for young individuals.
Influences of sex:
Square features are associated with males, and
rounded or oval with females.
Incisal edge of maxillary anterior teeth follows the
curve of the lower lip for females.
Distal surface of the maxillary central incisor is
rotated posteriorly for females. The mesial portion of
the lateral incisor usually overlaps the central incisor in
case of females.
In males the central incisor’s distal half overlaps the
lateral incisor.
Distal surface of female canines are rotated distally
making only mesial half visible. In males even the
distal surface is visible when viewed from fronatal
aspect.
ARRANGING TEETH FOR COMPLETE
DENTURE OCCLUSION
Maxillary Central Incisor:
The long axis of the tooth is perpendicular to
the horizontal
(labiolingual inclination)
Its long axis slopes towards the vertical axis
( mesiodistal inclination)
Slopes labially about 15 degrees when
viewed from the side.
Incisal edge is in contact with the occlusal
plane.
Maxillary Lateral
Incisor:
Long axis slopes rather more
towards the midline
Inclined labially about 20
degrees when viewed from
the side
The neck is slightly depressed
The incisal edge is about
1mm short of the occlusal
plane.
Maxillary Canine :
Its long axis is parallel to the
vertical axis when
viewed from both the front
and side or it may be
slightly to the distal.
The bulbous cervical half of
the tooth provides its
prominence.
Its cusp is in contact with the
horizontal plane.
.
The neck of the tooth must
be prominent
Remaining maxillary teeth are arranged on the other side of the
arch to complete the anterior set up.
To maintain the set teeth in position, the wax supporting the teeth
must be heated and sealed both to the teeth and to the record base.
Overjet and overbite
First premolar:
• Long axis is parallel to the
vertical axis when viewed from
the front or the side.
• Its palatal cusp is about 1mm
short of, and its buccal cusp in
contact with, the occlusal plane.
Second premolar:
• Its long axis is parallel with
the vertical axis when viewed
from the front or the side.
• Both buccal and palatal cusps
are in contact with the
occlusal plane.
First molar:
• Long axis slopes buccally
when
viewed from the front, and
distally when viewed from
the side.
• Only mesiopalatal cusp is in
contact
with the occlusal plane.
Second molar:
• Long axis slopes buccally more
steeply
than the first molar when viewed
from
the front, and distally more steeply
when viewed from the side.
• All four cusps are clear of the
occlusal
plane, but the mesiopalatal cusp is
nearest to it.
Arranging the
Mandibular Teeth
Mandibular central incisor:
• Long axis slopes slightly towards the
vertical
axis when viewed from the
front.
• Slopes labially when viewed from the side.
• Incisal edge is about 2mm above occlusal
plane
Mandibular lateral incisor:
• Long axis inclines to vertical
axis when viewed from the
front
• Slopes labially when viewed
from side but not so steeply
as the central incisor.
• Incisal edge is about 2mm
above occlusal plane
Mandibular canine:
• Long axis leans very slightly towards
the midline when viewed from the
front.
• Leans very slightly lingually when
viewed from the side
• Neck is slightly prominent and the
tooth is tilted to the distal
• Tip at same level as incisors.
First premolar:
• Long axis is parallel to the vertical plane when
viewed from the front and the side.
• Its lingual cusp is below the horizontal plane
• Its buccal cusp about 2mm above it as it contacts
the mesial marginal ridge of the upper first
premolar.
Second premolar:
• Long axis is parallel to the vertical plane when
viewed from both the front and the side.
• Both cusps are about 2mm above the occlusal
plane.
• The buccal cusp contacts the fossa between the
two upper premolars.
First molar:
• Long axis leans lingually when viewed from the front
and mesially when viewed from the side.
• All cusps are at a higher level above the occlusal plane
than those of the second premolar.
• The buccal and distal cusps are higher than the mesial
and lingual.
• The mesiobuccal cusp occludes in the fossa between
upper second premolar and first molar.
Second molar:
• Lingual and mesial inclination of the long axis is more
pronounced than in the case of the first molar.
• All the cusps are at a higher level above the occlusal
plane than those of the first molar, the distal and buccal
cusps more so than the mesial and lingual.
• The mesiobuccal cusp contacts the fossa between the
two upper molars.
Posterior teeth arrangement
Arrangement of 33 degrees anatomic maxillary
posteriorstteeth
1 molar- distobuccal cusp 0.5mm from
the plane
-distolingual cusp 0.5-0.75mm
from the plane
2nd molar-mesiobuccal cusp 1mm from
occlusal plane
Buccal ridges of molars are angulated
slightly inwards from line extending
along facial surfaces of canine and two
premolars and mesiobuccal surface of 1st
molar.
Posterior teeth arrangement
Selection of posterior molds
Surveying of mandibular cast
Articulation of 33 degrees anatomic mandibular
posterior teeth- 1st molar
2nd molar
2nd premolar
1st premolar
OCCLUSAL SCHEMES FOR COMPLETE DENTURE
OCCLUSION
The occlusal scheme or the tooth molds selected occlusal
rehabilitation will depend on the concept of occlusion that has been
selected to satisfy the needs of the patient. The posterior teeth,
arrangement according to the occlusal concept selected, should
fulfill the dentist's philosophy of occlusion as which appear
esthetically pleasing.
Prosthetic tooth anatomy seems to be more important to
dentists than to the patients who use the teeth. In the absence of
clear evidence of the benefits of one tooth anatomy compared with
others, dentists should use the least complicated procedures and
tooth forms that will satisfy their concepts of occlusion and
articulation of a mucosal supported dentition
.
There are several schools of thought on the choice of occlusal
forms of posterior teeth for the three concepts of occlusion most
often selected, namely, (1) bilateral balance,
(2) monoplane or nonanatomical, and
(3) lingualized articulations.
Anatomical molds usually are selected for bilateral
balanced articulation; however, nonanatomical teeth can be used in
a balanced concept with the use of compensating curves.
Nonanatomical or cusp less teeth are generally the choice
for monoplane although teeth with cusps also can be used. For the
lingualized occlusal concept, a combination of upper anatomical
and lower nonanatomical molds has been introduced by several
tooth manufacturers .
Arranging Anatomical Teeth to a
Balanced Articulation
The anterior teeth are set with a minimal vertical
overlap of 0.5 to 1 mm and 1 to 2 mm of horizontal overlap to
establish a low incisal guidance .
In the arrangement of the 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 Maxillary Teeth First
In arranging the maxillary posterior teeth first, start with
the maxillary first premolar and continue the arrangement of the
teeth through to the second molar. During the positioning of these
teeth, the maxillary lingual cusps are aligned with the reference
line that has been scribed on the mandibular wax occlusal rim
from the mandibular canine tip to the middle of the retromolar
pad.
Positioning the maxillary teeth with a slight opening of
the contact points between these teeth allows the mandibular
teeth to better assume their correct mesiodistal position as they
are interdigitated with the maxillary posterior teeth.