مرکز منطقه ای اطلاع رساني علوم و فناوري - THE COMPARISON OF HOUNSFIELD UNIT VALUESWITH THE BONE RESISTANCE DURING IMPLANT SURGERY: A PILOT STUDY

Abstract :

Objective: The purpose of this study was to compare Hounsfield unit (HU) values that were obtained during the radiological examination and the bone resistance which is felt during surgery by the clinicians. Material and Method: After a mandible obtained from a human cadaver that was kept in formalin has been scanned with dental volumetric tomography, a surgical stent was prepared with stereolitografic modeling and drilled with the help of a trephine bur in nine places. Prior to this drilling process, the drilling places were determined and the densities were detected in terms of HU. The clinician has marked the encountered bone resistance on a “visual analogue scale” in each region without knowing the HU values. Then, the values that the clinician determined and the HU values were examined statistically using Pearson s correlation analysis. Results: The highest HU values were detected in the interforaminal region (408-742). The values recorded for the posterior regions, especially for the region around the first molars were much lower (14-66). Pearson correlation values between the clinician scores and HU values showed a positive 98 % significance (r:0.980; p:0.001). Conclusion: Although more studies have to be accomplished in order to gain more reliable results, in the light of this pilot study, it may be concluded that an experienced clinician is capable of estimating the bone density in an implant surgery site.