RDA Dental Charting, Tooth Morphology, and Occlusion 2

Question 1

Using the Universal Numbering System, what number is assigned to the maxillary left central incisor?

Accepted Answer

#9

Answer

In the Universal Numbering System, #9 is the maxillary left central incisor. Numbering begins at #1 (upper right third molar) and goes across the top to #16, then down to #17 and across the bottom to #32.

Question 2

Which tooth surface faces toward the cheek?

Accepted Answer

Buccal

Answer

The buccal surface faces the cheek (buccinator muscle). For anterior teeth, the term 'labial' is used instead, referring to the surface facing the lips.

Question 3

What is the name of the type of occlusion where the mesiobuccal cusp of the maxillary first molar occludes in the buccal groove of the mandibular first molar?

Accepted Answer

Class I

Answer

Class I occlusion (Angle's Classification) describes the ideal relationship where the mesiobuccal cusp of the maxillary first molar occludes in the buccal groove of the mandibular first molar.

Question 4

On a dental chart, which symbol typically indicates a tooth that has been extracted?

Accepted Answer

X through the tooth

Answer

A tooth that has been extracted is typically indicated by an X through the tooth number or diagram on a dental chart.

Question 5

Which permanent tooth has a distinctive Carabelli's cusp?

Accepted Answer

Maxillary first molar

Answer

Carabelli's cusp (or cusp of Carabelli) is a fifth cusp sometimes found on the mesiolingual surface of the maxillary first molar. It is a morphological variation.

(RDA) Registered Dental Assistant Practice Test

(RDA) Registered Dental Assistant Practice Test

RDA Dental Charting, Tooth Morphology, and Occlusion 2