ABSTRACT
Objective: This study aimed to evaluate the validity and reliability of three bite registrations on articular disc position in temporomandibular disorder patients using magnetic resonance imaging (MRI). Materials and Methods: Fifteen clinically symptomatic and orthodontically untreated temporomandibular disorder patients within the age range of 17–40 years (mean age: 28.5 years) were examined. Each patient was subjected to three bite registrations, namely maximum intercuspation, initial contact bite and Roth power centric bite, and evaluated with MRI. Results: On the right side, the mean vertical and horizontal measurement values of the point in the most posterior aspect of the posterior band of the articular disc in relation to horizontal reference line (HRL) and vertical reference line (VRL) in the sagittal view in the Roth power centric bite were lesser (2.720 ± 1.239 mm and 2.380 ± 1.185 mm, respectively), in comparison with the other two bites, and on the left side too, it was lesser in the Roth power centric bite (2.293 ± 0.979 mm and 2.360 ± 1.078 mm, respectively), when compared to the other two bites. Statistical analysis also showed the significance of Roth power centric bite over the other two bites. Conclusions: Favourable articular disc positional changes were observed in the Roth power centric bite followed by the initial contact bite and that maximum disc recapture was observed in most patients with the Roth power centric bite rather than in initial contact bite and maximum intercuspation positions. The Roth power centric bite could be assumed to be the ideal method for articulation and fabrication of gnathological splints for treating patients with temporomandibular disorders.