A study of the effects of chewing patterns on occlusal wear

The chewing cycle is a functional movement, closely related to occlusion, t he neuromuscular system and the central nervous system. Although actual che wing paths are complicated and vary from individual to individual, there ar e two typical patterns. One is more vertical in nature and is similar to a chopping movement. The other is a more lateral type that is similar to a gr inding movement. The purpose of this study was to evaluate the effects of c hewing patterns on occlusal wear. Fifteen subjects exhibiting a chopping-ch ewing pattern and 15 subjects exhibiting a grinding-chewing pattern were se lected using a jaw tracking device. The occlusal wear values, obtained by b oth ordinal and Woda's arbitrary scales, and frequencies of non-working fac ets were calculated for each group. The occlusal wear values in all teeth a nd in each segment, obtained by the use of the ordinal scale did not vary s ignificantly between the chopping and the grinding type group. However, the occlusal wear values of the grinding type group in all teeth and in poster ior teeth segments, obtained by the use of Woda's arbitrary scale, were sig nificantly greater than those of the chopping type group. Frequencies of no n-working facets in posterior teeth showed no significant differences betwe en the groups.