Comparison Of Occlusalforce In Post-Orthodontic And Non-Orthodontic Subjects

Balanced occlusal force distribution is a critical factor for restorative, prosthetic or orthodontic treatment. It has been postulated that orthodontic treatment may lead to occlusal discrepancy in the arch due to change in occlusal relationship. This study was conducted to compare the occlusal force parameters between natural dentition and post-orthodontic treatment group. The sample comprised of 50 Thai subjects divided into 2 groups, with 25 subjects each in non-orthodontic and post-orthodontic groups (mean age 24.8 years). T-Scan III computerized occlusal analysis was used to record a multi-bite closure for each subject. Bilaterally force distribution, force in anterior and posterior quadrants and individual force percentage on every tooth in the arch were recorded in both groups. The results showed initial tooth contacts in both groups on second molars and central incisors. Significant difference was found between anterior and posterior occlusal force but no significant difference was observed bilateral force distribution. Statistically significant difference was observed in the quadrants between both groups with 22.46% anterior and 77.57% posterior force among non-orthodontic group and 10.58% anterior and 89.42% posterior force in post orthodontic group(P<0.01). A significant occlusal force discrepancy was found in the post-orthodontic subjects, with higher force percentages observed posteriorly and much less percentage force anteriorly, when compared to the natural dentition subjects. Therefor, T-Scan digital occlusal analysis may be recommended for occlusal loading evaluation as part of orthodontic case finishing.