This document provides an overview of occlusion concepts in fixed partial dentures. It discusses theories of occlusion such as Bonwill's triangular theory, the conical theory, and the spherical theory. It also covers classifications of occlusion by Dawson, concepts such as bilateral balanced occlusion and mutually protected occlusion, determinants of occlusion including condylar guidance and anterior guidance, and curves of occlusion like the curves of Spee and Wilson. The document is intended as a reference for understanding occlusion in prosthodontic treatments involving fixed partial dentures.