title: The Evaluation of Unscrewing Torque Values of Implant-Abutment Connections: An In Vitro Study.
abstract: OBJECTIVE
  This study investigated the stability of titanium screws in implant-abutment connections by measuring the force necessary to induce unscrewing.
  
  
  METHODS
  A total of 60 implant-abutment couplings were assigned to two groups (n = 30 each). The sequence 10-20-32 Ncm was tested in Group 1; the sequence 10-20-32-32-32 Ncm was tested in Group 2. The force necessary to unscrew each abutment-implant sample was recorded and statistically analyzed. The significance level was set at P < .05.
  
  
  RESULTS
  Significant differences were found between the two sequences. Group 2 required higher forces than Group 1 to unscrew.
  
  
  CONCLUSIONS
  The stability of the implant-abutment joint may be improved by tightening with the sequence 10-20-32-32-32 Ncm.
authors.forename: Ezio
authors.initials: E
authors.lastname: Bruna
authors.forename: Andrea
authors.initials: A
authors.lastname: Fabianelli
authors.forename: Giacomo
authors.initials: G
authors.lastname: Mastriforti
authors.forename: Federica
authors.initials: F
authors.lastname: Papacchini
mesh_terms: D059605:Dental Implant-Abutment Design; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D017276:Friction; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D019415:Torque
chemical_list: D014025:Titanium