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SELECTION OF ANTERIOR TEETH.

SELECTION OF ANTERIOR TEETH.. 1.LENGTH THE HEIGHT OF OCCLUSAL PLANE ACCORDING TO THE LENGTH OF THE UPPER LIP

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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 teeth

Properties 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