selection of teeth

1. Selection Of
Anterior Teeth In
Complete Denture
DR.ANJANA THOMAS

2. Contents
SIZE
FORM
COLOUR
How to select
anterior teeth?

4. Introduction
• Anterior teeth are primarily selected for aesthetics
• Posterior teeth are selected for mastication
• Both must function in harmony with each other and surrounding oral
environment
• There is no single rule of the thumb to decide the selection
• Certainly requires artistic skill in addition to scientific knowledge

5. Objectives In Selecting Artificial Teeth
• Establishing harmony with surrounding tissue.
• Maintenance of vertical dimension
• Aesthetic acceptability
• Masticatory efficiency

6. Selection of anterior teeth
SIZE
FORM
COLOR

7. LENGTH
SIZE
WIDTH

8. Width of teeth Size of face
• Average combined width of the maxillary
anterior teeth is determined by dividing the
bizygomatic width by 3.3
• Pound stated that zygoma was mostly present
1–1.5 inches behind the lateral corner of the
eyes
• Average width of the maxillary central incisor
is determined by dividing the bizygomatic
width by 16

10. Width of teeth Size of head
• Ratio of the cranial circumference (glabella
to occiput) to the width of upper anterior
teeth has been shown to be 10:1
.

11. Width of teeth Anatomical
landmarks
• Mark or pin is placed at the corners of the mouth
on the wax occlusal rims
• Width of the maxillary anterior arch is determined
by measuring the distance from the two marks
with a flexible ruler
• Parallel lines are extended from the lateral surface
of the ala of the nose onto the maxillary occlusal
rim
• Line tentatively gives the position of apex of
canine teeth indicating the width of the maxillary
anteriors

12. Width of teeth anatomical landmarks
• Through the distal border of incisive papilla a
line is drawn perpendicular to the midline of
palate and continued onto the edge of master
cast. The tips of the canine teeth should lie near
the point of intersection of this line with the
labial surface of the occlusal rim. A flexible ruler
can be used to measure this distance
• If the cuspid eminences are evident, a line
placed at its distal termination in the cast gives
a measure of the anterior maxillary arch. If the
eminences are not evident, the buccal frenum
can be used as a guide for the arch.

14. Maxillomandibular relations
• In class III arches, the mandibular anterior teeth are selected larger than
normal
• In class II arches, the mandibular anterior are selected smaller than normal

16. Contour of the residual ridges
• The artificial teeth should be placed to follow the contour of the residual ridges that existed
when the natural teeth were present
• Thus the size of anterior teeth is selected according to this position. The loss of contour as
a result of resorption, accident or surgery may make this a difficult task.
• Resorption of the maxillae anteriorly is in a vertical and palatal direction, while posteriorly
it is in a vertical and medial direction. Resorption of the mandible anteriorly is in a vertical
and lingual direction, while posteriorly it is in a vertical and slightly lingual direction
• There also may be a relationship between the form of the residual ridge and the form of the
teeth – square, tapering and ovoid

17. Length of teeth length of face
• Average length of the maxillary central incisor is determined by dividing the
length of the face by 16
• Length of the face is a measure of distance from the hairline to the lower edge
of the bone of the chin, with the face at rest

18. Vertical distance between the ridges
• Determines the length of the teeth
• When space is available, it is more
aesthetically acceptable to use teeth
that are long enough to eliminate the
display of denture base

19. Lips
• Guides the selection of length of
maxillary anterior teeth.
• At rest, the relationship of incisal
edges of the central incisors to the lip
line, given by Frush and Fischer,
1958)
• Depends on the age and sex of the
individual
Type of
individual
Amount of
tooth exposure
below lip line
at rest
Young female 3 mm
Young male 2 mm
Middle aged 1–1.5 mm
Elderly 0–2 mm above
lip line at rest

21. Form of Anterior teeth
• Form and contour of face
• Dentogenic concept
• Pre-extraction records

22. Form and contour of face
• Form of a tooth should conform to the contour of the
face as viewed from the front and side (profile)
• According to Leon William’s classification, facial forms
can be categorized as square, square tapering,
tapering and ovoid, when viewed from front
• Three areas in the face are considered for this –
temporal, zygomatic and angle of mandible
• To determine the facial profile, forehead, base of nose
and chin points are considered. The profiles can be
classified as – straight or convex and teeth are
selected accordingly

24. Facial profile and form of teeth

25. Dentogenic concept
• Concept was advocated by Frush and Fisher (1957)
• Based on Sex, Personality And Age Of The Patient (SPA concept or factors)
• Teeth were selected and arranged according to this concept

26. SPA concept
• Sex: Curved facial features are associated with femininity and square with
masculinity. To create harmony between the tooth form and face, teeth of
females may be more ovoid or tapering than square as compared to males.
The incisal edges may also be rounded for females. Square feature is
associated with masculinity
• Personality: A vigorous personality requires square teeth with flat incisal
edges, while a delicate personality will require ovoid teeth
• Age: With age, the teeth wear at the incisal edges and interproximal surfaces.
Labial surfaces seem flatter and form appears squarer. The same should be
considered while selecting the teeth

28. Pre-extraction records
• These can provide information about the size and form of both anterior teeth. These include:
1. Facial photographs: Provide general information about the width and outline form of anterior
teeth through an algebraic proportion.
2. By comparing, clearly visible factors like interpupillary distance of patient in photo and in person
with the tooth width in photo, the actual width of the anterior tooth can be calculated.
3. Diagnostic casts: Casts of patient’s natural or restored dentition provide information, which is
useful to select the size and form of anterior teeth.
4. Radiographs: They can provide information about the size and form of teeth.
5. Teeth of close relatives: Son’s or daughter’s tooth size, colour and arrangement can be
effectively used in selecting and arranging artificial teeth for their parents.
6. Extracted teeth: Provide information about the size and form; should not be used for selecting
colour

29. Color
• Definition: A phenomenon of light or
visual perception that enables one to
differentiate otherwise identical objects
(GPT8).
• Dimensions
• Colour has three dimensions according
to the Munsell system – hue, value and
chroma. Translucency is a fourth
dimension, which is the property of an
object that permits the passage of light
through it.

30. Factors
• The following parameters assist in selecting the colour of the artificial teeth.
• Colour of hair, eyes and skin
• Individuals with blue, green or light coloured eyes and fair skin are given teeth with lighter
shade, while those with black or dark eyes and ruddy complexion are given darker teeth.
• Some authors have also suggested a relation between colour of the hair and tooth colour,
but this is a very unreliable guide as the patient could be dyeing the same.
• Although there is no scientific correlation between the above factors and tooth colour, in
general the selected artificial tooth colour or shade should be in harmony with these
factors.

31. Age
• With increasing age, tooth colour becomes progressively darker.
• When young, the pulp chambers are large & the increased blood supply, lightens the tooth
colour. With age, formation of secondary dentin reduces the size of the pulp chamber,
making teeth appear more opaque & dark.
• As wear occurs on the teeth as a result of age, they also become smoother and reflect
more light. But the attrition at the incisal edge contributes to decreased translucency with
age.
• Teeth also pick up stains with age and acquire a brownish colour

32. Sex
• Darker shade is generally selected for men and lighter shade for women.
Pre-extraction records
• A record of the patient’s tooth colour before extraction can be a useful guide in selecting
the colour, but extracted teeth are unreliable as they dehydrate and become lighter.

33. Selecting colour
• Colour or shade of the artificial teeth for
complete dentures is selected by placing the
shade tab in the following areas
• Along the side of the nose – establishes the
basic hue, chroma and value
• Under the lips with only the incisal edge
exposed – reveals the effect of the colour of
the teeth when the patient’s mouth is relaxed
• Under the lip with only the cervical end
covered and mouth open-simulates the
exposure of the teeth as in a smile

34. The squint test
• May be helpful in evaluating the colour of teeth with complexion of face.
• With the eyelids partially closed to reduce light, the dentist compares the
selected shade tabs by holding them along the face of the patient
• The colour that fades from view first is the one that is least conspicuous and is
in harmony with the colour of the face

35. Thank you