title: Alveolar bone stress around implants with different abutment angulation: an FE-analysis of anterior maxilla.
abstract: OBJECTIVE
  To comparatively assess the masticatory stress distribution in bone around implants placed in the anterior maxilla with three different labial inclinations.
  
  
  METHODS
  Three-dimensional finite element models were fabricated for three situations in anterior maxilla: (1) a fixture in contact with buccal cortical plate restored by straight abutment, (2) a fixture inclined at 15 degrees, and (3) 20 degrees labially restored with corresponding angled abutment. A palatal bite force of 146 N was applied to a point 3 mm below the incisal edge. Stress distribution around the bone-fixture interface was determined using ANSYS software.
  
  
  RESULTS
  The maximum compressive stress, concentrated in the labial crestal cortical bone, was measured to be 62, 108, and 122 MPa for 0-, 15-, and 20-degree labially inclined fixtures, respectively. The maximum tensile stress, concentrated in the palatal crestal cortical bone, was measured to be 60, 108, and 120 MPa for 0-, 15-, and 20-degree labially inclined fixtures, respectively.
  
  
  CONCLUSIONS
  While all compressive stress values were under the cortical yield strength of 169 MPa, tensile stress values partially surpassed the yield strength (104 MPa) especially when a 20-degree inclination was followed for fixture placement.
authors.affiliation: Department of Oral and Maxillofacial Prosthodontics and Implants, Tehran University of Medical Sciences (TUMS), School of Dental Medicine, Tehran, Iran.
authors.forename: Roozbeh
authors.initials: R
authors.lastname: Sadrimanesh
authors.forename: Hakimeh
authors.initials: H
authors.lastname: Siadat
authors.forename: Pooyan
authors.initials: P
authors.lastname: Sadr-Eshkevari
authors.forename: Abbas
authors.initials: A
authors.lastname: Monzavi
authors.forename: Peter
authors.initials: P
authors.lastname: Maurer
authors.forename: Ashkan
authors.initials: A
authors.lastname: Rashad
mesh_terms: D000539:Alveolar Process / Q000502:physiology; D001696:Biomechanical Phenomena; D001732:Bite Force; D019245:Compressive Strength; D003198:Computer Simulation; D000044:Dental Abutments; D059605:Dental Implant-Abutment Design; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D003799:Dental Stress Analysis / Q000379:methods; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D008437:Maxilla / Q000000981:diagnostic imaging / Q000502:physiology*; D011859:Radiography; D013718:Tensile Strength
chemical_list: D015921:Dental Implants