title: [Finite element stress analysis of all-ceramic continuous crowns of the lower anterior teeth in differential shoulder thickness].
abstract: OBJECTIVE
  To investigate the stress distributions under load in 3 types of all-ceramic continuous crowns of the lower anterior teeth with differential shoulder thickness.
  
  
  METHODS
  Cone-beam CT (CBCT) was used to scan the in vitro mandibular central incisors, and achieve three-dimensional finite element model of all-ceramic continuous crowns with different shoulder width by using Mimics, Abaqus software. Different load conditions were simulated based on this model to study the effect of shoulder width variation on finite element analysis of 3 kinds of different all-ceramic materials of incisors fixed continuous crowns of the mandibular.
  
  
  RESULTS
  Using CBCT, Mimics10.01 software and Abaqus 6.11 software, three-dimensional finite element model of all-ceramic continuous crowns of the mandibular incisor, abutment, periodontal ligament and alveolar bone was established. Different ceramic materials and various shoulder width had minor no impact on the equivalent stress peak of periodontal membrane, as well as alveolar bone. With the same shoulder width and large area of vertical loading of 120 N, the tensile stress was the largest in In-Ceram Alumina, followed by In-Ceram Zirconia and the minimum was IPS.Empress II. Under large area loading of 120 N 45° labially, when the material was IPS.Empress II, with the shoulder width increased, the porcelain plate edge of the maximum tensile stress value increased, while the other 2 materials had no obvious change.
  
  
  CONCLUSIONS
  Finite element model has good geometric similarity. In the setting range of this study, when the elastic modulus of ceramic materials is bigger, the tensile stress of the continuous crown is larger. Supported by Research Project of Department of Education, Jiangxi Province (GJJ09130).
authors.affiliation: Department of Prosthodontics, Affiliated Stomatological Hospital of Nanchang University. Nanchang 330006;China.E-mail:ouyang5666845@126.com.
authors.forename: Shao-bo
authors.initials: SB
authors.lastname: Ouyang
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Hong-bin
authors.initials: HB
authors.lastname: Zhang
authors.forename: Lan
authors.initials: L
authors.lastname: Liao
authors.forename: Hong-shui
authors.initials: HS
authors.lastname: Zhu
mesh_terms: D002516:Ceramics; D003442:Crowns; D003776:Dental Porcelain; D003799:Dental Stress Analysis; D020342:Finite Element Analysis; D006801:Humans; D007180:Incisor
chemical_list: C483026:In-Ceram Alumina; C485633:In-Ceram Zirconia; D003776:Dental Porcelain