MANDIBULAR CUSPIDS

The mandibular cuspid (tooth #22 or #27) is illustrated in figure 4-34. These teeth, like the mandibular incisors, are smaller and more slender than the opposing teeth in the maxillary arch.

Facial Surface\The facial surface of a mandibular cuspid is much the same as that of a maxillary cuspid, except that the distoincisal cutting edge is almost twice the length of the mesial edge.

Lingual Surface\The lingual surface as a rule is very smooth, and a cingulum is rarely present.

Root Surface\The single root is not so long as that of the maxillary cuspid and is much flatter mesiodistal.

MAXILLARY FIRST BICUSPID

The maxillary first bicuspid (tooth #5 or #12), illustrated in figures 4-35 and 4-36, is the fourth tooth from the midline. It is considered to be the typical bicuspid. (The word "bicuspid" means "having two

Figure 4-35.\Surfaces of maxillary first bicuspid.

Figure 4-36.\Features of an occlusal surface of maxillary first bicuspid.

cusps.") Sometimes bicuspids are called premolars because they are just in front of the molar teeth.

Facial Surface\The facial surface is somewhat similar to the facial surface of the cuspid. However, the tip of the facial cusp is located in the center of the "biting" edge, which is called the occlusal edge or occlusal margin. From the cusp tip to the cervical margin, there is a slight ridge, called the facial ridge, similar to the facial ridge found in cuspid teeth.

Lingual Surface\The lingual surface is narrower and shorter than the facial surface, and is smoothly convex in all directions. The cusp tip is in the middle of the occlusal edge.

Root Surface\The root is quite flat on the mesial and distal surfaces. In about 50 percent of maxillary first bicuspids, the root is divided in the apical third, and when it so divided, the tips of the facial and lingual roots are slender and finely tapered.

Occlusal Surface\The occlusal surface (fig. 4-36) has a facial cusp and a lingual cusp. There are mesial and distal marginal ridges. Two fossae are on the occlusal surface-the mesial and distal fossae.

MAXILLARY SECOND BICUSPID

The maxillary second bicuspid (tooth #4 or #13), illustrated in figure 4-37, resembles the first bicuspid very closely, but is smaller in dimensions. The cusps are not as sharp as the maxillary first bicuspid and have only one root.

MANDIBULAR FIRST BICUSPID

The mandibular first bicuspid (tooth #21 or #28), illustrated in figure 4-38, is the fourth tooth from the midline. It is the smallest of the four bicuspids. The term bell-crowned is used to describe its appearance. The mandibular first bicuspid has many characteristics of a cuspid.

Occlusal Surface\A large facial cusp, which is long and well defined, and a small nonfunctional lingual cusp are present on the mandibular first bicuspid.

Root Surface\The root of the mandibular first bicuspid is usually single, but on occasion can be bifurcated (two roots).