title: Effect of Different Abutments and Connections in Deformation Crestal Bone.
abstract: BACKGROUND
  The use of Morse taper connections is increasing, but little is known about the biomechanical use of abutments and their use in fixed prostheses.
  
  
  OBJECTIVE
  This study evaluated the transmission of load on the bone implant-supported dentures, varying the type of prosthetic connection and abutment.
  
  
  METHODS
  Using 4 polyurethane models, 3 implants were inserted into each block, establishing the following groups: (a) external hexagon and Micro-Unit abutments; (b) external hexagon and UCLA abutment; (c) Morse taper and Micro-Unit abutments; and (d) Morse taper and UCLA abutments. The prosthetic structures were cast, and in a universal testing machine, load was applied midway between the implants, with cantilever intervals of 5, 10, 15, 20, and 25 mm. Data were analyzed by Mann-Whitney, Friedman, and Kruskal-Wallis tests (P < 0.05).
  
  
  RESULTS
  Regarding the prosthetic connection, there was no difference in the use of hexagonal or Morse taper, but the use of Micro-Unit abutment showed lower deformation values than UCLA for the 2 connections.
  
  
  CONCLUSIONS
  The use of intermediate abutments affects the distribution of masticatory loads: the greater the length of the cantilever, the greater the surface deformation of the bone around the distal implant.
authors.affiliation: *Professor, Department of Prosthodontics, Paulista University (UNIP), São Paulo, Brazil. †Student of the Graduate Program, Master in Dental Clinics, Paulista University (UNIP), São Paulo, Brazil. ‡Head, Graduate Program in Dentistry (UNIP), Paulista University (UNIP), São Paulo, Brazil. §Professor, Department of Dental Materials and Prosthodontics, Paulista State University (UNESP), Özcan, Zürich, Switzerland. ¶Professor, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, University of Zurich.
authors.forename: Alfredo Mikail Melo
authors.initials: AM
authors.lastname: Mesquita
authors.forename: Juliano H M
authors.initials: JH
authors.lastname: Silva
authors.forename: Cintia Helena Cury
authors.initials: CH
authors.lastname: Saraceni
authors.forename: Alberto N
authors.initials: AN
authors.lastname: Kojima
authors.forename: Mutlu
authors.initials: M
authors.lastname: Özcan
mesh_terms: D000044:Dental Abutments; D059605:Dental Implant-Abutment Design; D019094:Dental Prosthesis, Implant-Supported / Q000295:instrumentation / Q000379:methods*; D003799:Dental Stress Analysis; D066298:In Vitro Techniques; D011140:Polyurethanes; D013314:Stress, Mechanical; D016474:Weight-Bearing
chemical_list: D011140:Polyurethanes