Occlusal analysis by the digital T-Scan III System compared with Hanel occlusal foil

Background: The number of occlusal contacts per tooth, reproducibility, and repeated usage of the digital T-Scan III System (TS) with Sensor foil (SF) are compared in vivo with Hanel foil (HF). Materials and methods: The static occlusion of 20 volunteers (average age: 25 years) with complete natural dentition without reconstructions or temporomandibular disorders (TMDs) was tested using HF, and compared with those tested using TS (with SF). To test intraexaminer reliability, the contacts by the TS and HF were evaluated twice, with an interval of 6 months. Reproducibility was tested by using five different HFs or SFs in two volunteers. For the TS stress test, one foil was used twice in three volunteers. Results: Intraexaminer reliability was excellent. Overall, HF showed significantly more contacts (P = 0.001), especially in posterior teeth (P = 0.002); SF revealed significantly more contacts in anterior teeth (P = 0.003). Repeated assignment of occlusal contacts was reliable for HF but not for SF. The number of contacts was significantly less in the second usage of the same SF (P = 0.001). Conclusion: SF should not be used for occlusal analysis or occlusal adjustment. Keywords: occlusion, T-Scan, Hanel foil (HF), Sensor foil (SF), occlusal analysis, occlusal equilibration, occlusal indicator