title: Stress distribution in delayed replanted teeth splinted with different orthodontic wires: a three-dimensional finite element analysis.
abstract: OBJECTIVE
  The aim was to evaluate the biomechanical behavior of the supporting bony structures of replanted teeth and the periodontal ligament (PDL) of adjacent teeth when orthodontic wires with different mechanical properties are applied, with three-dimensional finite element analysis.
  
  
  METHODS
  Based on tomographic and microtomographic data, a three-dimensional model of the anterior maxilla with the corresponding teeth (tooth 13-tooth 23) was generated to simulate avulsion and replantation of the tooth 21. The teeth were splinted with orthodontic wire (Ø 0.8 mm) and composite resin. The elastic modulus of the three orthodontic wires used, that is, steel wire (FA), titanium-molybdenum wire (FTM), and nitinol wire (FN) were 200 GPa, 84 GPa, and 52 GPa, respectively. An oblique load (100 N) was applied at an angle of 45° on the incisal edge of the replanted tooth and was analyzed using Ansys Workbench software. The maximum (σmax) and minimum (σmin) principal stresses generated in the PDL, cortical and alveolar bones, and the modified von Mises (σvM) values for the orthodontic wires were obtained.
  
  
  RESULTS
  With regard to the cortical bone and PDL, the highest σmin and σmax values for FTM, FN, and FA were checked. With regard to the alveolar bone, σmax and σmin values were highest for FA, followed by FTM and FN. The σvM values of the orthodontic wires followed the order of rigidity of the alloys, that is, FA > FTM > FN.
  
  
  CONCLUSIONS
  The biomechanical behavior of the analyzed structures with regard to all the three patterns of flexibility was similar.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araçatuba Dental School, Unesp - Univ Estadual Paulista, Araçatuba, Brazil.
authors.forename: Fernando Isquierdo
authors.initials: FI
authors.lastname: de Souza
authors.forename: Wilson Roberto
authors.initials: WR
authors.lastname: Poi
authors.forename: Vanessa Ferreira
authors.initials: VF
authors.lastname: da Silva
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Martini
authors.forename: Regis Alexandre da Cunha
authors.initials: RA
authors.lastname: Melo
authors.forename: Sonia Regina
authors.initials: SR
authors.lastname: Panzarini
authors.forename: Eduardo Passos
authors.initials: EP
authors.lastname: Rocha
mesh_terms: D000497:Alloys; D001696:Biomechanical Phenomena; D003188:Composite Resins; D003198:Computer Simulation; D003799:Dental Stress Analysis; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008437:Maxilla; D003765:Models, Dental; D008982:Molybdenum; D009969:Orthodontic Wires; D013232:Steel; D014025:Titanium; D014057:Tomography, X-Ray Computed; D018677:Tooth Injuries / Q000628:therapy*; D014090:Tooth Replantation / Q000379:methods*; D055114:X-Ray Microtomography
chemical_list: D000497:Alloys; D003188:Composite Resins; D013232:Steel; C013616:nitinol; D008982:Molybdenum; D014025:Titanium
keywords: avulsion; biomechanics; dental trauma; finite element analysis