Clinic Study On Tarnslocation Of Condylar In Correcting Anteiror Teeth Cros&-Bite By Removable Appliance In Mixed Dentiiton

Objective: To study the effect of removable interocclusal lip archappliance on condylar translocation in correcting anterior teeth cross-bite inmixed dentition.Methods: X-ray pictures of35mixed dentition cross-bite patients, whowere treated between2009and2011, were analyzed before and aftertreatment by removable interocclusal lip arch appliance. In the region of TMJ,the contour line of articular fovea of TMJ, condyle process, articular tubercleand squamotympanic fissure were traced by transparent parchment.According to Madsen measurement, both anterior and posterior spaces ofTMJ were measured in the X-ray picture. The difference between before andafter treatment was analyzed by statistical t-test. The position of condylar wasdecided by linear percentage of anterior and posterior spaces of TMJ.Results: Before treatment, anterior space of TMJ was1.58±0.15mm,after treatment the space was2.49±0.16mm, and there was statisticalsignificance in difference between the two values (P<0.05). Before treatment,posterior space of TMJ was4.31±0.20mm, after treatment the space was2.71±0.17mm, and there was statistical significance in difference between thetwo values (P<0.05). The linear percentage of TMJ space before treatmentwas46%, the after was4%. Conclusion: Removable interocclusal lip arch appliance, by which tocorrecting mixed dentition anterior teeth cross-bite, can make condylar moveback to median position in TMJ fossa and keep stable.