Statement of problem: The concept of canine protection and group function lack consistency in the definitions and examining methods, and a valid system for evaluating and classifying occlusal contact patterns has not been established.
Purpose: This study assessed the use of canine protection and group function in classifying occlusal guidance in the natural dentition.
Material and methods: Occlusal contacts of 86 young adults were examined with shim stock in regulated lateral positions, 0.5,1,2 and 3 mm from the maximum intercuspation. The patterns of occlusal contacts varying with the lateral position were described.
Results: Focusing on the working-side contact only, most contact patterns belonged to group function, and a few to canine protection. Focusing on both the working and nonworking side contacts, nearly half the contact patterns were those other than canine protection and group function and were classified into balanced occlusion.
Conclusion: The validity of the classification system using canine protection and group function is questionable. A new classification system of occlusal guidance is desirable.