INFLUENCE OF CHOICE OF REFERENCE POINT ON THE CONDYLAR MOVEMENT PATHSDURING MANDIBULAR MOVEMENTS

Series of four open-close, protrusive and lateral movements were recor ded by the six degrees of freedom jaw movement recording system OKAS-3 D in 20 healthy subjects. Consequently the movement paths of nine cond ylar points, the palpated lateral pole and eight points located on a s quare parallel to the sagittal plane with an edge of 10 mm and centred around the lateral pole were calculated. For all movements except the protrusive movements, the 3-D excursions of the condylar points stron gly depended upon the choice of condylar reference point (ANOVA, P < 0 .001). During laterotrusive movements the Bennett angle and the Bennet t shift also varied significantly according to the position of the ref erence point (ANOVA, P < 0.001). The results of this study underline t hat comparison of condylar movements between different studies is only possible when the same condylar reference point is used. General cons ensus on the choice of condylar reference point is thus needed.