RDA Dental Charting, Tooth Morphology, and Occlusion 4

Question 1

Which tooth has a distinctly heart-shaped cross-section at the cervical third?

Accepted Answer

Maxillary central incisor

Answer

The maxillary central incisor has a heart-shaped (triangular) cross-section at the cervical third due to its labial convexity and lingual concavity.

Question 2

In the Universal Numbering System, which tooth is #17?

Accepted Answer

Mandibular left third molar

Answer

In the Universal system, #17 is the mandibular left third molar; numbering continues from #16 (maxillary left third molar) around the arch.

Question 3

A charting symbol of a red circle drawn around an existing restoration indicates:

Accepted Answer

A restoration present that is defective or needs replacement

Answer

A red circle or outline around a charting symbol denotes an existing condition that is defective and requires treatment.

Question 4

Which cusp of the maxillary first molar is the smallest and located on the mesiolingual line angle?

Accepted Answer

Cusp of Carabelli

Answer

The cusp of Carabelli is an anomalous fifth cusp found on the mesiolingual surface of the maxillary first molar and is the smallest cusp.

Question 5

In Angle's Class II Division 2 malocclusion, how are the maxillary central incisors positioned?

Accepted Answer

Lingually inclined (retroclined)

Answer

Class II Division 2 is characterized by a distal molar relationship with maxillary central incisors that are retroclined (tipped lingually).

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