Objective: The aim was to investigate the relationship between the appearance of double contours on the mandibular condyle and changes in articular disc position after splint therapy.
Study design: Panoramic radiographs and magnetic resonance images of 82 joints in 41 patients taken before and after treatment were studied. The number of cases showing a double contour after treatment was compared between the 2 groups with and without disc displacement before treatment, and between the 2 groups with and without reduction in the displacement group; a comparison was also made among age groups and among 3 groups showing improvement, aggravation, or no change in displacement after treatment.
Results: All joints showing a double contour after treatment showed articular disc displacement before treatment. No double contours were observed after treatment on joints without articular disc displacement before treatment. All joints showing a double contour showed improvement in disc displacement.
Conclusion: The results indicate that a double contour on the mandibular condyle is the result of repositioning of, or positional improvement in, a displaced articular disc.