Comparison of retruded axis articular mountings with and without applied muscular force.

The study reported compared the positions of the horizontal axis of rotation of the condyles when R.A.P. registrations were taken on seven subjects using; (1) An anterior jig with chinpoint guidance. (2) An anterior jig with chinpoint guidance and applied muscle force by the subject. (3) An anterior jig with bilateral manipulation (i.e. bilateral support of the body of the mandible by the operator). The results showed that the most superior positions were obtained with the technique using the anterior jig with chinpoint guidance and applied muscle force, which was also the most inconsistent technique. The technique using the anterior jig with chinpoint guidance was most consistent, and the mean difference between retruded axis position and intercuspal position using this technique was 0.31 mm on the right side and 0.34 mm on the left side.