It is often curved, as in a cylinder. We will speak often of the occlusal surface of a tooth. Wheeler's text also defines it as an elevation on the crown of a tooth making up a divisional part of the occlusal surface. It makes up the bulk of the cervical third of the lingual surface. It is named according to its location or form.
Examples are buccal ridges, incisal ridges, marginal ridges, and so on.
Four specific types are defined below. See cusp ridge at right. Marginal ridges are those rounded borders of enamel which form the margins of the surfaces of premolars and molars, mesially and distally, and the mesial and distal margins of the incisors and canines lingually. Triangular ridges are those ridges which descend from the tips of the cusps of molars and premolars toward the central part of the occlusal surface. Transverse ridges are created when a buccal and lingual triangular ridge join.