Peter Camper described ala-tragus line for orientation of antro-posterior occlusal plane and defined it as a line running from the lower border of the ala of the nose to the tragus of the ear. Camper never mentioned exact point of reference for this line of the tragus of the ear; superior, inferior or middle. The aim of this study was to evaluate the effect of changing the posterior reference point of ala-tragus line on masticatory efficiency of complete denture wearers.
Subjects and method : Ten completely edentulous patients were selected. For each patient new complete denture was constructed. The denture anterior teeth were set to meet the esthetic needs with minimal incisal guidance as much as possible. Posterior anatomic form teeth were arranged in balanced articulation with the posterior occlusal plane follow the ala tragus line at the middle point of tragus. Then, the denture posterior segments were exchanged twice to orient occlusal plane parallel to the ala tragus line at the superior and the inferior points of tragus, respectively. After three months of each new and modified denture use, masticatory efficiency test was carried out.
Results: There were no significant differences of all masticatory efficiency parameters (when patients were chewing apple, peanut and carrot) with the occlusal plane oriented parallel to the Camper's line using the three levels of the tragus.
Conclusion: According to the results of the present study, the use of any posterior point of tragus for occlusal plane orientation is acceptable at the point of masticatory efficiency.