Occlusion is the foundation for everything a dentist does that involves teeth. A thorough knowledge of occlusion is the basis for understanding why teeth get loose, why they wear excessively, break cusps, fracture restorations, or shift position. the act of occluding : the state of being occluded: such as. a : the complete obstruction of the breath passage in the articulation of a speech sound. b : the bringing of the opposing surfaces of the teeth of the two jaws into contact also : the relation between the surfaces when in contact. Enamel-to-enamel contact areas that occur over time can...