Effect Of Implant Length And Abutment Material On Implant Stability

Methods:  The OSS requires disassembly for placement of the fixture level testing pin and only mode of testing. PER does not require disassembly facilitating stability testing at any level and for this study at: 1) fixture level (FL) with impression coping; 2) 3mm multi-unit abutment (MUA) level and Ti temporary cylinder; 3) 4mm solid Ti healing abutment (HA). Simulated jaw bone was created with solid polyurethane block Sawbones® using 2mm thick layer (40 pcf,0.64g/cc) resembling cortical bone and 40mm thick (20pcf,0.32g/cc) resembling trabecular bone). Branemark MkIII implants (Groovy, Nobel Biocare) in lengths of 7,8.5,10,11.5,13,15,18mm were placed following manufacturer’s surgical protocol seating to 30Ncm. Implants were measured 10 times with each system in a randomized order. Means(sd), and linear regression analysis-correlation were calculated.

Results: Mean ISQ values ranged from 69.5 to 77.5 (sd=0.51 to 0.79) for increasing implant length. Regression analysis revealed a significant correlation, p<0.05. Mean ELC for 1) FL ranged from 0.07655 to 0.08391 (sd=.0015 to .0069) no correlation found; 2) MUA ranged from .0907 to .0937 (sd=.0004 to .0009) regression analysis revealed a significant correlation, p<0.05; 3) HA ranged from -.0092 to .06825 (sd=.004 to .0086) no correlation found.

Conclusions: A significant positive correlation was found between implant length and ISQ values. No correlation was distinguished between implant length and Energy Loss Coefficient for FL or HA but MUA values were significant. The Periometer was technique sensitive and requires further research to validate its accuracy.