What describes the union of two triangular ridges that produces one ridge across the occlusal surface?

The correct answer is that a transverse ridge refers to the union of two triangular ridges, resulting in a single ridge that runs across the occlusal surface of a tooth. This anatomical feature is commonly found on the molars and contributes to the occlusion and function of the teeth during chewing.

Transverse ridges are important in dental anatomy as they provide tooth stability and aid in the distribution of occlusal forces. Understanding this feature helps dental professionals in various aspects of restorative dentistry, ensuring that the integrity and function of the tooth are maintained or restored.

In contrast, longitudinal ridges run in the same direction as the long axis of the tooth, and oblique ridges, found on maxillary molars, are formed by the joining of two triangular ridges but are oriented diagonally. Marginal ridges, meanwhile, refer to the raised borders of enamel found on the mesial and distal sides of the occlusal surface but do not involve the union of triangular ridges.