title: Biomechanical effects of two different collar implant structures on stress distribution under cantilever fixed partial dentures.
abstract: OBJECTIVE
  The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures.
  
  
  METHODS
  The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated.
  
  
  RESULTS
  In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models.
  
  
  CONCLUSIONS
  It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.
authors: Near East University, Faculty of Dentistry, Department of Prosthodontics, Mersin, Turkey. gokcemeric@yahoo.com
authors: Gökçe
authors: G
authors: Merıç
authors: Erkan
authors: E
authors: Erkmen
authors: Ahmet
authors: A
authors: Kurt
authors: Atilim
authors: A
authors: Eser
authors: Ahmet Utku
authors: AU
authors: özden
mesh_terms: D000497:Alloys; D000538:Aluminum Silicates / Q000737:chemistry; D001696:Biomechanical Phenomena; D002858:Chromium Alloys / Q000737:chemistry; D003198:Computer Simulation; D000044:Dental Abutments; D003722:Dental Alloys / Q000737:chemistry; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D003776:Dental Porcelain / Q000737:chemistry; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D003801:Dental Veneers; D003779:Denture Design; D003830:Denture, Partial, Fixed; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008334:Mandible / Q000502:physiology; D008954:Models, Biological; D016348:Osseointegration / Q000502:physiology; D017680:Potassium Compounds / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D000538:Aluminum Silicates; D002858:Chromium Alloys; D003722:Dental Alloys; D015921:Dental Implants; D017680:Potassium Compounds; D003776:Dental Porcelain; C016447:feldspar; C031462:titanium alloy (TiAl6V4); D014025:Titanium