Int J Oral Maxillofac Implants 21 (2006), No. 4 15. July 2006
Purpose: 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 under-dimensioned implant bed preparation was also studied for both implant designs.
Materials and 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.
Conclusion: 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.
Keywords: bone condensing, conical implants, dental implants, primary stability, tapering angle of implants