The document discusses occlusion and dynamic occlusion. It defines occlusion as the relationship between all components of the masticatory system during normal function, parafunction, and dysfunction. Dynamic occlusion refers to the occlusal contacts made as the mandible moves relative to the maxilla, guided by muscles and anterior/posterior guidance mechanisms. It describes different occlusal contacts that occur in centric position, protrusive position, and lateral positions on working and non-working sides.