Tapered Versus Cylindrical Implant: Which Shape Inflicts Less Pain After Dental Implant Surgery? A Clinical Trial.

PURPOSE: Because no study has evaluated the postoperative pain caused by the shape of dental implants, this study compared the level of postoperative pain between tapered and cylindrical implants inserted in the posterior region of the maxilla. MATERIALS AND METHODS: The study was designed as a double-blinded randomized clinical trial and conducted in 50 healthy patients 20 to 60 years old who were edentulous in the posterior maxilla and were candidates for single implantation. All patients had the same surgical difficulty with appropriate bone width and height. BioHorizons (Birmingham, AL) implants (tapered vs cylindrical) with 4.5-mm platform diameter were randomly selected for each group. The visual analog scale was used to evaluate the level of pain. Pain severity in each group was measured at 30-minute, 3-hour, 6-hour, 12-hour, 24-hour, 2-day, 3-day, and 1-week intervals. The predictor variable was implant shape and the outcome was postoperative pain severity. Data were statistically analyzed with SPPS 16 (SPSS, Inc, Chicago, IL) at the significance level of a P value less than .05. RESULTS: Fifty patients (n = 25 per group) with the mean age of 43.7 +/- 10.9 years were included in this study. The pain level in the 2 groups reached its maximum at the 6-hour postoperative interval. Pain severity decreased significantly over time in the 2 implant groups (P < .001). Severities of postoperative pain in the tapered group at 3-, 6-, 12-, and 24-hour intervals were statistically lower than those in the cylindrical group (P < .05). CONCLUSIONS: Implant shape had an impact on postoperative pain. It can be concluded that tapered implants lead to less postoperative pain compared with cylindrical ones.