Post on 23-Feb-2016
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SELECTION OF ANTERIOR TEETH.
ANTERIOR TEETH
SIZE SHAPE (MOLD) SHADE MATERIAL
SIZE
1.LENGTH
THE HEIGHT OF OCCLUSAL PLANE
ACCORDING TO THE LENGTH OF THE UPPER LIP.
SIZE
HIGH LIP LINE
LOW LIP LINE
HIGH LIP LINE
HIGH LIP LINE
LOW LIP LINE
THE AMOUNT OF UPPER TEETH SHOWING BELOW THE UPPER LIP DEPENDS ON:
• LENGTH OF UPPER LIP.• MOBILITY OF THE UPPER LIP.
• VERTICAL HEIGHT OF OCCLUSION.
SIZE
2. WIDTH
Size: Width:
**Width of the six maxillary
anteriors is slightly less than one
third of the bizygomatic width.
**The width of the natural central
incisor,1, approximately 1/16 the
bizygomatic width of the patient’s face.
**A vertical line extending along the
lateral surface of the ala often will pass
through the middle of the natural upper
canine.
CANINE LINES
Distance between the 2 canine lines = MD width of the six anterior teeth
A LINE PERPENDICUAR TO THE MIDLINE, PASSING THROUGH THE POSTERIOR BORDER OF THE INCISIVE PAPILLAE.
CANINE POSITION ON THE CAST.
SHAPE (MOLD)
Outline form of the face
The shape of the
upper central
incisors should be in
harmony with the
shape of the face.
OVOID TAPEREDSQUARE
SQUARED
OVOID
TAPERED
Shape of the arch form
* The shape of the teeth should be in harmony with the shape of the arch
SQUARED TAPERED (V- shaped) OVOID
SHADE
Shade (color ) of the teeth
For the selection of the
color of the anterior
teeth a shade guide is
used
►Selection of a suitable shade depends on:
Age of the patient.
Color of the patients’ face.
Patients’ general complexion.
Patients’ personal approval.
►The shade of a tooth is a composite of 4 qualities:
► Hue
► Saturation
► Brilliance
► Translucency
Hue: Is referred to as the basic color; the color of the tooth is basically yellow.
Saturation: the amount of hue (color) / unit area ; (Chroma) color intensity.
Brilliance: the degree of black (darkness) and white (Value) (lightness) areas of an object. Should be graduated with age.
Translucency: it’s the property of an object that permits the passage of light through it but does not give a distinguishable image…makes the teeth look ALIVE.
Characteristics of natural teeth
1. The neck has a more pronounced color than the incisal
edge.
2. The incisal edge is more translucent than the body
because it is composed mainly of enamel.
3. Upper central incisors are the lightest teeth in the
mouth.
Characteristics of natural teeth
4. Upper laterals, lower centrals and laterals are
slightly darker .
5. Upper and lower canines are darker.
6. Teeth darken slightly with age.
MATERIAL
Tooth material• Artificial teeth may be made of:
1. Acrylic resin
2. Porcelain
3. Metal
4. Combination between acrylic resin and metal
5. Cross-linked acrylic resin.
6. A mix of composite and resin.
Acrylic resin teethProperties of acrylic resin teeth:1. Low sp. Gravity2. Chemical union with acrylic denture bases3. Less noisy4. Easily modified by grinding5. Less harmful to the underlying tissues due to their
resiliency6. Low abrasion resistance7. Can be used in small inter-arch distance
Porcelain teeth
• They need mechanical means of retention pins for anterior teeth and holes for posterior teeth
Properties of porcelain teeth
1. Mechanical means of retention
2. Heavier in weight
3. Noisy in use
4. Cant be modified
5. High abrasion resistance
6. Very brittle
PROPERTY ACRYLIC PORCELAIN
1-COMPOSITION. POLYMETHYL METHACRYLATE
FELDSPATHIC PORCELAIN (HIGH FUSING)
2-SPECIFIC GRAVITY. LOW HIGH
3-RESISTANCE TO WEAR AND ABRASION. WEAR EASILY RESIST ABRASION AND
WEAR (PRESERVES V.D)
4-EASE OF ADJUSTMENT. EASY DIFFICULT
5-RESILIENCY. RESILIENT BRITTLE
6-SOUND ON OCCLUSION. NO CLICKING CLICKING
7-EFFECT ON UNDERLYING TISSUES. HARMLESS HARMFUL
8-METHOD OF UNION WITH DENTURE BASE. CHEMICAL BOND MECHANICAL BOND
9-EFFECT OF DIRECT HEAT. AFFECTED NOT AFFECTED
10-INDICATIONS*NARROW INTERARCH
SPACE*FLAT AND FLABBY RIDGES
*WIDE INTERARCH SPACE*WELL DEVELOPED
RIDGES.
ANTERIOR TEETH
SIZE SHAPE (MOLD) SHADE MATERIAL