Initial exploration of clinical application of mandibular expansion combined with fixed orthodontic techniques-braking force system
Objective To explore the feasibility of mandibular expansion combined with fixed appliance-braking force system for improving the mandibular expansion efficiency. Methods The combination of maxillary and mandibular expansion with fixed appliance-braking force system was applied to correct 10 patients with Angle's class Ⅰ malocclusion with moderate crowding and maxillary constriction during the peak adolescent growth period. Cone beam computed tomography (CBCT) images were taken at four stages of treatment[pre-expansion (T0),immediately after expansion force removal (T1),immediately after expansion appliance removal (6 months post-expansion,T2),and post-treatment (T3)]. CBCT images were used to measure the intermolar width,interapical width,included angle between tooth long axes and the horizontal plane,and the distance from the enamel-cementum junction to the alveolar crest,to observe changes in tooth position and alveolar bone remodeling. Results CBCT measurements showed that the intermolar width of all teeth increased at T0-T1;the intermolar width decreased at T1-T3 (except for the first molar),and the intermolar width of the first molar increased at T2-T3;the interapical width of all teeth decreased at T0-T1,and the interapical width of the canines and the second premolar continued to increase at T1-T3,while the interapical width between the first premolar and the first molar decreased at T2-T3;the changes in intermolar width were less than those in interapical width. The included angle between the long axis of all teeth and the horizontal plane increased at T0-T1,and gradually decreased from T1 to T3 (except for the first molar),and the included angle of the first molar had a small increase at T2-T3. The distance from the enamel-cementum junction to the alveolar crest increased in all teeth at T0-T1 and gradually decreased at T1-T3,and alveolar bone height gradually recovered. Conclusion Mandibular expansion combined with fixed appliance-braking force system holds promise for enhancing mandibular expansion efficiency.
Narrow dental archAngle's class Ⅰ malocclusionMandibular expansionMandibular expansion combined with fixed appliance-braking force systemMandibular expansion efficiency
万方数据
维普
