The class III jaw relations patient possesses challenging changes in occlusal patterns. The interocclusal distance, evelope of motion, chewing stroke, tooth-to-tooth relations, and the determinants of occlusion vary from the criteria established for the class I or class II occlusions. The lack of anterior guidance and the added width and length of the mandible have a significant effect on occlusal morphology. Several stable forms of occlusal relationships can be found at one time in the same dentition. The occlusal morphology is dictated by the condylar movements and mandibular size. The balancing cusps must provide the proprioceptive guidance for the chewing cycle. One half to 1 mm, rest interocclusal distance is adequate to allow the teeth to separate in speech and function. © 1990 Mosby-Year Book, Inc.