title: Biomechanical effects of corticotomy approaches on dentoalveolar structures during canine retraction: A 3-dimensional finite element analysis.
abstract: BACKGROUND
  Corticotomy has proven to be effective in facilitating orthodontic tooth movement. There is, however, no relevant study to compare the biomechanical effects of different corticotomy approaches on tooth movement. In this study, a series of corticotomy approaches was designed, and their impacts on dentoalveolar structures were evaluated during maxillary canine retraction with a 3-dimensional finite element method.
  
  
  METHODS
  A basic 3-dimensional finite element model was constructed to simulate orthodontic retraction of the maxillary canines after extraction of the first premolars. Twenty-four corticotomy approach designs were simulated for variations of position and width of the corticotomy. Displacement of the canine, von Mises stresses in the canine root and trabecular bone, and strain in the canine periodontal ligament were calculated and compared under a distal retraction force directed to the miniscrew implants.
  
  
  RESULTS
  A distal corticotomy cut and its combinations showed the most approximated biomechanical effects on dentoalveolar structures with a continuous circumscribing cut around the root of the canine. Mesiolabial and distopalatal cuts had a slight influence on dentoalveolar structures. Also, the effects decreased with the increase of distance between the corticotomy and the canine. No obvious alteration of displacement, von Mises stress, or strain could be observed among the models with different corticotomy widths.
  
  
  CONCLUSIONS
  Corticotomies enable orthodontists to affect biomechanical responses of dentoalveolar structures during maxillary canine retraction. A distal corticotomy closer to the canine may be a better option in corticotomy-facilitated canine retraction.
authors: Graduate student, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, Chongqing, China.
authors: Chongshi
authors: C
authors: Yang
authors: Assistant professor, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, Chongqing, China.
authors: Chao
authors: C
authors: Wang
authors: Professor, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, Chongqing, China.
authors: Feng
authors: F
authors: Deng
authors: Professor, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing Medical University, Chongqing; professor, Key Laboratory for Biomechanics and Mechanobiology of Chinese Education Ministry, International Research Center for Implantable and Interventional Medical Devices, Beihang University, Beijing, China. Electronic address: yubofan@buaa.edu.cn.
authors: Yubo
authors: Y
authors: Fan
mesh_terms: D000539:Alveolar Process / Q000502:physiology*; D001696:Biomechanical Phenomena; D003481:Cuspid / Q000502:physiology*; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D019516:Orthodontic Space Closure / Q000379:methods; D009969:Orthodontic Wires; D010027:Osteotomy / Q000379:methods*; D010513:Periodontal Ligament / Q000502:physiology; D013314:Stress, Mechanical; D019228:Tooth Crown / Q000502:physiology; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods*; D014092:Tooth Root / Q000502:physiology