Relationship of anatomic landmarks with occlusal plane

Abstract

Purpose : Evaluation of relationship between various anatomical landmarks and the occlusal plane in the natural dentition that could be used for establishing the occlusal plane in complete dentures. Methods : The study comprised of 100 dentulous subjects with all healthy permanent teeth in normal arch form and alignment. Three instruments were custom-made for the purpose : the occlusal plane analyzer to check the parallelism of the ala-tragus lines,and the interpupillary line, the buccinator groove relator and the level analyzer for the level of the linea alba buccalis with the occlusal plane. For the retromolar pad area a metallic scale was used. Results : Within limitations of this study, it was observed that, only 13% subjects showed occlusal plane parallel to the interpupillary line. The posterior reference point of Camper's line was middle point for 72% of males and superior point for 80% of females. Intraorally, 68% of subjects have the occlusal plane at the same level as that of buccinator groove and 77% of the subjects had the occlusal plane at the middle one-third of retromolar pad area. Interpretation and Conclusions : It was concluded that: the occlusal plane is parallel to Camper's plane posterior reference point as the superior point of tragus in females and middle point in males. The occlusal plane is not generally parallel to the interpupillary line. Intra-orally, the level of buccinator groove is reliable, while variations in retromolar pad area make it an unreliable landmark for orienting the occlusal plane.