Methods: Subjects fulfilled the criteria of physiologic occlusion by Mohl (1988) were examaimed. The criteria consisted of occlusal stability, satisfaction with masticatory function, acceptable speech articulation and acceptable esthetic.The subjects' occlusal schemes on the left and right sides were classified as canine protected occlusion, group function, or unclassified according to the definition from Glossary of Prosthodontic Terms (8(th) edition). In addition, the presence of occlusal interferences during mandibular excursions, as well as measurement of static and dynamic occlusal relationships were recorded such as the horizontal overlap, vertical overlap, Angle’s classification, active mouth opening including lateral and protrusive excursions, discrepency between retruded contact positon (RCP) and maximum intercuspation (MIC) was also performed
Results: Total of 124 subjects (60.5% female, age 17 – 50 years old)were included in this study. The average number of teeth per subject was 28.98±1.3. The majority of the populations (69.4%) possessed group function occlusal scheme. We also found that occlusal interference was presented in 20.2% of the population.The most common occlusal interferenece was protrusive interference (12.1%). About 80% possessed Angle classification I. The mean vertical overlap and horizontal overlap were 1.88±1.25 and 2.33±1.31 mm. The average maximum mouth opening, left and right excursive /protrusive movement was 46.52±4.57, 8.77±1.3, 8.55±1.23, and 6.28±1.55 mm repectively
Conclusions: The common characteristic of physiologic occlusion among Thais are group function occlusal scheme, Angle classification I, absence of occlusal interference, approximate 45 mm of mouth opening with minimal RCP-MIP discrepency.