title: Stress distribution on scalloped implants with different microthread and connection configurations using three-dimensional finite element analysis.
abstract: OBJECTIVE
  The objective of this study was to investigate the effects of different microthread designs and implant-abutment connection configurations of scalloped implants on stress distribution in bone using three-dimensional finite element analysis.
  
  
  METHODS
  Three different designs of scalloped implants (two different microthread designs and one without microthreads) with two different connection systems and two flat-top implants with similar connection systems were compared in a bone model that mimicked the anterior maxilla. Vertical and oblique (30-degree) loading with 100 N of force was applied to eight models. Peak stress levels and the distribution of stress were observed.
  
  
  RESULTS
  The stress pattern of scalloped implants was distinctively different from that observed on flat-top implants. Scalloped implants showed peak stresses in the proximal cortical bone as well as in the buccal and palatal cortical bone, whereas flat-top implants showed peak stresses mainly in the buccal and palatal cortical bone and limited stress in the proximal bone. The scalloped implant without microthreads and a conical platform-switched connection demonstrated the lowest peak stress levels. The scalloped implant with a straight platform connection generally showed peak stress that was two to three times higher than that seen in the conical platform-switched model.
  
  
  CONCLUSIONS
  Peak stress levels in scalloped implants varied with microthread designs, connection configurations, and the direction of loading. The conical platform-switched connection seemed more important for a scalloped implant than the microthread design in reducing loading stresses exerted on the surrounding bone. Scalloped implants without microthread and a with a conical platform-switched connection or closed microthreads and a conical platform-switched connection showed consistently lower buccal bone stress than the flat-top implants in areas where the bone had a sloping and scalloping shape.
authors.affiliation: Department of Prosthodontics, School of Dentistry, Pusan National University, Busan, South Korea.
authors.forename: Kyung-soo
authors.initials: KS
authors.lastname: Choi
authors.forename: Seong-hun
authors.initials: SH
authors.lastname: Park
authors.forename: Jae-hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Young-chan
authors.initials: YC
authors.lastname: Jeon
authors.forename: Mi-Jung
authors.initials: MJ
authors.lastname: Yun
authors.forename: Chang-mo
authors.initials: CM
authors.lastname: Jeong
mesh_terms: D000539:Alveolar Process / Q000502:physiology*; D003198:Computer Simulation; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis / Q000379:methods; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional
chemical_list: D015921:Dental Implants