Investigation of Three Different Total Maxillary Arch Distalization Methods with Skeletal Anchorage Using Finite Element Analysis

Aim: This study aimed to investigate three skeletally anchored maxillary arch distalization methods (MKS appliance, IZC and MT screws) using finite element analysis and analyze the stresses on the screws and surrounding periodontal tissues.

Material and Methods: The craniomaxillary complex, maxillary teeth, periodontal ligament, alveolar process and planned mechanics were modeled for finite element analysis. Nine scenarios with three distalization mechanics were created. Tooth displacements in the x, y and zaxis were calculated and the Von Mises stress distributions of the screw and surrounding tissues were visualized.

Results: In the molar region, the most distalization at the crown level was seen in the 'first scenario' in the MKS group. At the root level, the most distalization was seen in the 'third scenario' in the MKS group. In the incisor region, the maximum palatal movement at the crown level was seen in the 'ninth scenario' in the MT group. At the root level, the maximum palatinal movement was seen in the IZC group in the 'sixth scenario'.

Conclusion: All three mechanics achieved effective distalization despite different movement patterns. In the MKS and IZC groups, where the force was shifted 3 and 6 mm apically, movements converging towards the center of resistance were advantageous for treating Class II division 2 malocclusion with low upper incisor inclinations. In the first, fourth, and MT group scenarios, movements when the force was applied at the archwire level were advantageous for treating Class II division 1 malocclusion with high upper incisor inclinations.