title: Primary stability of a conical implant and a hybrid, cylindric screw-type implant in vitro.
abstract: OBJECTIVE
  The differences with respect to primary stability between 2 Camlog implants, a conical implant, and a hybrid cylindric screw-type implant, were investigated in vitro. The effect of underdimensioned implant bed preparation was also studied for both implant designs.
  
  
  METHODS
  In an in vitro model the stability of different implants in fresh porcine iliac bone blocks was measured using torque moment values, the Periotest, resonance frequency analysis, and push-out testing.
  
  
  RESULTS
  The conical implant showed significantly higher primary stability than the cylindric hybrid implant using the insertion torque, Periotest, and push-out tests. For both types of implants, the torque moment values following under-dimensioned preparation were significantly better than those obtained following the standard drilling protocol (Conical: 25.00 vs 11.00 Ncm; Cylindrical: 11.75 vs. 5.75 Ncm). For the cylindric implant, significantly better results following under-dimensioned implant bed preparation were observed only with the insertion torque and the pushout testing values. The mean ISQ values for all groups were between 55 and 57; no statistical differences with respect to ISQ could be found.
  
  
  CONCLUSIONS
  In this in vitro model conical implants showed higher primary stability than cylindric implants. The procedure of under-dimensioned drilling seemed to increase primary stability for both types of implants; however, the effect was only observable using insertion torque. RFA and Periotest, the noninvasive, clinical methods tested, did not clearly demonstrate this difference.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital Mainz, Mainz, Germany.
authors.forename: Jun
authors.initials: J
authors.lastname: Sakoh
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wahlmann
authors.forename: Elmar
authors.initials: E
authors.lastname: Stender
authors.forename: Rer
authors.initials: R
authors.lastname: Nat
authors.forename: Bilal
authors.initials: B
authors.lastname: Al-Nawas
authors.forename: Wilfried
authors.initials: W
authors.lastname: Wagner
mesh_terms: D000818:Animals; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D013552:Swine; D019415:Torque
chemical_list: D015921:Dental Implants