Surfaces and line angles

Mesial, distal, buccal, lingual, occlusal — then the lines where they meet.

Objectives

Name every surface on an anterior and a posterior tooth.
Define a line angle and a point angle.
Describe height of contour on facial and lingual.

Paint a surface

Teal is the surface you named. Line angles are where two surfaces meet.

Mesial: Toward the midline of the arch. On anterior teeth this is toward the central incisors.

Read this

Surfaces

Posterior teeth have five surfaces: mesial, distal, buccal, lingual, occlusal. Anteriors replace occlusal with incisal and buccal with labial. Facial covers labial and buccal. Palatal is maxillary lingual.

Line angles and point angles

A line angle is the junction of two surfaces (mesiobuccal). A point angle is the junction of three (mesiobucco-occlusal). You will use these names when you talk about contacts, finish lines, and where a chip started.

Height of contour

The greatest bulge on a surface. Facial height of contour on anteriors and premolars sits in the gingival third. Lingual of molars sits in the middle third. If a CAD crown fattens the gingival third, the gingiva pays for it.

Open the practice lab

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