title: Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant-abutment connection.
abstract: OBJECTIVE
  Position stability of the abutment should be investigated in four implant systems with a conical implant-abutment connection.
  
  
  METHODS
  Previously developed formulas and an established experimental setup were used to determine the position stability of the abutment in the four implant systems with a conical implant-abutment connection and different positional index designs: The theoretical rotational freedom was calculated by using the dimensions of one randomly selected implant per system for approximated geometric models. Experimentally, the rotation, the vertical displacement, and canting moments of the abutment after multiple repositioning and hand tightening of the abutment screw were investigated.
  
  
  RESULTS
  The experimental rotation and vertical displacement differed between the implant systems tested. The analytical and experimental results for the rotation of the abutment clearly deviated in the three implant systems.
  
  
  CONCLUSIONS
  Malpositioning of the abutment was possible in all the implant systems tested. Deviating theoretical and experimental results suggest high manufacturing tolerances during fabrication of the implant components.
  
  
  CONCLUSIONS
  Position stability of the abutment is essential for precisely fitting implant-supported superstructures.
authors: Department of Oral and Maxillofacial Surgery, University Hospital Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany.
authors: Wiebke
authors: W
authors: Semper-Hogg
authors: Silvan
authors: S
authors: Kraft
authors: Sebastian
authors: S
authors: Stiller
authors: Juergen
authors: J
authors: Mehrhof
authors: Katja
authors: K
authors: Nelson
mesh_terms: D000044:Dental Abutments; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D017268:Dental Prosthesis Retention; D003799:Dental Stress Analysis; D012399:Rotation
chemical_list: D015921:Dental Implants