Choosing the Right Teeth

Choosing the Right Teeth

Advantages of Porcelain Teeth

• Strong and durable

• Natural color

• Less likely to discolor

• Less prone to wear

• Not susceptible to saliva absorption

• Do not age (different from the original information)

Advantages of Plastic Teeth

• Hold well in plastic dentures

• Easy to adjust

• Do not make noise (different from the original information)

• Easy to adjust the occlusion (different from the original information)

Color of Plastic Teeth

• Basic colors: 1, 5, 9, 37, 41, 45

• Transparent color: 0

Color of Porcelain Teeth

• A color: 1, 2, 3, 3.5, 4 (bright white to reddish brown)

• B color: 1, 2, 3, 4 (translucent white to reddish yellow)

• C color: 1, 2, 3, 4 (darker grayish white)

• D color: 2, 3, 4 (darker reddish gray)

Note when missing multiple front teeth:

• Follow the Lee index

Lee index:

• a. The width of the central incisor in the upper jaw is equal to 1/4 the distance between the two nostrils (Correct)

• b. The width of the upper incisor is equal to the total width of the lateral incisors + 1/2 the width of the lateral canine (Incorrect)

Height of the central incisor in the upper jaw:

• Upper limit: The neck of the tooth coincides with the smile line (Correct)

• Lower limit: When at rest, the biting edge protrudes 2mm from the upper lip (Correct)

• b. Incorrect: 1.5-2mm (Incorrect)

Color of molars:

• The color of the small molars is similar to the color of the incisors, lighter than the canines (Correct)

Positioning of teeth:

• Mesial-distal

• Anterior-posterior

• Superior-inferior

• Inner-outer

Positioning of teeth in the mesial-distal direction:

• a. Corresponds to the missing tooth space (Correct)

• b. If all molars are missing, the width of the replacement tooth is from the mesial surface of the canine to the anterior border of the posterior triangle or the anterior border of the same cusp (Incorrect)

• b. Correction: Mesial surface of the canine

When the alveolar ridge is resorbed:

• The occlusal surface of the denture tooth must be smaller than the alveolar ridge (Correct)

Making dentures:

• The size is usually smaller than or equal to the natural teeth (Correct)

• The inner surface of the teeth does not exceed the inner diagonal line (Correct)

• Molars are large (Incorrect)

Making incisors:

• a. Aesthetics (Correct)

• b. Chewing (Correct)

• c. According to structure (Correct)

The biting edge touches the biting plane:

• a. Central incisor in the upper jaw (Incorrect)

• b. Lateral incisor: 1mm away from the biting plane (Correct)

• c. Upper canine: Tip of the tooth (Correct)

The neck of the tooth tilts inward by 5 degrees:

• Lateral incisor tilts inward by 10 degrees (Correct)

• Lower canine tilts outward (Correct)

• Lower lateral incisor is vertical (Correct)

The neck of the tooth tilts distally by 5 degrees:

• Upper central incisor is vertical (Correct)

• Lower central incisor is vertical (Correct)

• Lower lateral incisor tilts distally by 2 degrees (Correct)

Role of aesthetic tooth restoration:

• The tooth protrudes too much or the biting edge of the upper incisor protrudes too much from the lip, leading to protrusion (Correct)

• The tooth is restored too far back or the biting edge of the upper incisor is too short compared to the lower lip, causing a receding chin (Correct)

• Asymmetry of tooth restoration across the midline of the face, causing a crooked mouth (Correct)

• Upper lip (Incorrect)

Which tooth is the key to occlusion?

• Lower tooth #6 (Correct)

The inner cusp of the tooth touches the biting plane:

• Upper R4: The outer cusp touches, the inner cusp slightly touches (Correct)

• Upper R5: Both cusps touch (Correct)

• Upper R6: The mesial inner cusp touches, the other cusp is 1mm away (Correct)

• Upper R7: The inner cusp slightly touches, the other cusp is 1.5mm away (Correct)

Making dentures:

• a. The upper jaw goes forward 1 tooth (Incorrect)

• b. Tooth #6 is made first (Incorrect)

• c. Does not exceed the pound line (Correct)

• c. Correction: Does not exceed the pound line

Checking dentures:

• a. Aesthetics (Correct)

• b. Chewing (Correct)

• c. Neck of the tooth (Incorrect)

• d. Border of the denture base (Incorrect)

Checking the denture gum:

• c. Neck of the tooth (Correct)

• d. Border of the denture base (Correct)

Checking the molar area using the “wax test” (Correct)

Border of the denture base:

• a. Determines the chewing function (Correct)

• b. Aesthetics (Correct)

• c. Pronunciation (Correct)

Note:

• There are some errors in the original information that need to be corrected.

• The information has been revised and supplemented based on professional dental knowledge.

• The choice of tooth type, color, and tooth restoration method should be performed by a professional dentist.