The Study Of Occlusal Contacts In Patients With Unilateral Posterior Crossbite

Objective To find the evidence of damage that unilateral posterior crossbite did to stomatognathic system system by investigating the characters of occlusal contacts in patients with unilateral posterior crossbite and comparing it with normal occlusion.Method22patients with unilateral crossbite patients were selected as the experimental group,22person with normal occlusion were selected randomly as the control group.The data of occlusal contacts of experimental group and control group were recorded with T-ScanⅢ system during intercuspal position, protrusive movement and lateral movement,and compared with normal occlusion. The results of two group were analyzed with statistical methods. Variance analysis were used to analyze distance from the Occlusal force center to midline, closing time, disclusion time; chi-square test were used to analyze the occurrence rate of premature contact and occlusal interference.Results The occlusion time,disclusion time and the distance between center line and center of occlusal force of UPCB group were longer than those in the control group and there were Significant differences between them, the occurrence rate of premature contact and Occlusal interference in patients were higher than that of normal occlusion.Conclusion The characteristic of occlusal contacts in patients with unilateral posterior crossbite have significant differences with normal occlusion. It’s occlusal stability is no better than normal occlusion. The center of occlusal force, occlusion time and disclusion time could be taken as theoretical basises for correction and reference of therapeutic effect.