In every case of restorative care, dentists deal with reference positions of the mandible. For this purpose, the intercuspal position and the retruded contact position are the most often used reference positions. Concerning how precisely these clinically relevant positions could be determined, insufficient knowledge was available 25 years ago. There was also uncertainty concerning the causal role of the occlusion in cases of temporomandibular disorders. It was established that the reproducibility of the retruded contact position and other reference positions established by the dentist, did not differ from one another. The position of the patient had no influence on reproducibility, nor did the choice of bite registration material. The intercuspal position is the most reproducible reference position in all conditions tested. The opinion, widely held at the time, that a discrepancy between the reference positions would lead to temporomandibular disorders was addressed in the dissertation ´Reference Positions in the Mandible´.