The relationship between non-working-side occlusal contacts and mandibular position.

No clear description can be found regarding the lateral position when examining non-working-side occlusal contacts. The objective of this study was to test the hypothesis that the non-working-side contact pattern varies with the mandibular position. The characteristics of the non-working-side contact pattern were also determined relative to the working-side contact pattern. Occlusal contacts of 86 young adults were examined using shim stock in standardized lateral positions: 0.5, 1, 2 and 3 mm from the maximum intercuspation (MI), where the 0.5, 1 and 2 mm positions were defined as lateral positions close to the MI and the 3 mm position as an edge-to-edge position. The frequency of non-working-side occlusal contacts decreased gradually from 0.5 to 3 mm position. The frequency of non-working-side contacts was significantly greater in the 0.5 and 1 mm positions than in the 3 mm position. Non-working-side occlusal contacts occurred in nearly half of the 0.5 mm positions. Non-working-side contacts were significantly less frequent with canine protection than with group function for the 0.5 and 1 mm positions. There were no significant differences between the two occlusal schemes for the 2 and 3 mm positions. In conclusions, the non-working-side contact pattern varied with the mandibular position. These results suggest that clinical examination should include contact patterns both in a position close to the MI and in an edge-to-edge position, i.e. in functional and parafunctional ranges. Likewise, data from occlusal contact research should include a standardized definition of mandibular position.