Does Shelf preperation have an efficacy on primer stability of 4 implants  supporting screw retained full arch fixed dental prosthesis ? 

Abstract
Purpose:  The purpose of this study is to compare primary stability of implants placed with or without bone reduction and shelf preparation. 
Patients and Methods:  This retrospective comparative study enrolled twenty patients. . The Primary predictor, bone reduction, was coded as a binary variable.10 of patient were underwent bone reduction procedure, while the rest 10 patient do not applied bone reduction and shelf preparation prior to implant site preparation. Width, length and bone density were also assessed as secondary predictor variables. Resonance Frequency Analyses (RFA) values and insertion torques  (IT) of all implants were used as outcome variable.
Results:  Bone reduction and shelf preparation do not have statistically significant effect on IT and RFA values of implants. While there was no statistically significant difference on IT and ISQ values  regarding implants’ width and length, bone density has statistically significant effect.
Conclusion: Bone reduction and shelf preparation do not affect primary stability of implants as a single factor. Some other factors such as implant size and bone density should be considered to evaluate primary stability.

Does Shelf preperation have an efficacy on primary stability of 4 implants supporting screw retained full arch fixed dental prosthesis ?