Download or read book A Multicenter Prospective Randomized Clinical Trial Assessing Implant Design Modifications After 3 Years written by Raes Stefanie and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Background:The clinical outcome of implant therapy depends, apart from patient-related factors, on implant-related factors such as surface topography, design and prosthetic connection. Although nano-surface modifications increase osseointegration, initial implant stability at time of placement is an important clinical factor in implant survival and is considered a prerequisite for early or immediate loading protocols.Aim:This RCT evaluates the 3 years outcome of modifications of the OsseoSpeed implant (Dentsply Sirona Implants, Mu00f6lndal, Sweden) in terms of survival, bone level and peri-implant health. Alterations in the OsseoSpeed EV consisted of changes in dimensions of body shape, drilling procedures, drill design and abutment connection compared to the original OsseoSpeed TX.Material and methods:120 partially edentulous patients, enrolled in five clinics, were randomized to test (EV) and control (TX). 59 subjects received 79 EV and 61 subjects received 87 TX implants respectively. Cemented permanent restorations were placed on average 9 weeks later on titanium stock abutments. Peri-implant bone level changes, plaque, probing pocket depths and bleeding indices were assessed at restoration placement (baseline), and thereafter at 6, 12 and 36 months.Statistical comparison between EV and TX were done with Mann Whitney U-test with p0.05 as significance level.Results:104 subjects (50 EV, 54 TX) were assessed (66 and 75 implants respectively) after 3 years. Three patients discontinued due to failure, 7dropped out and 6 were not available. The groups were comparable (p0.05) regarding age, gender, race, smoking habits, tooth loss reason, periodontal history, implant location, length and diameter. Mean implant insertion torque was 30u00b113 Ncm and 22u00b19 Ncm for EV and TX, indicating improved stability for the modified protocol. Five of 79 EV implants were lost (93.6%, 4 prior and 1 post-loading). One of 87 TX implants failed prior to loading (98.9%). This difference was not statistically significant. Regarding crestal bone change, a mean gain was observed from baseline to 3 years of 0.29mm (SD 0.72) and 0.21mm (SD 0.48) for EV and TX respectively. Probing pocket depth at 3 years was 2.72mm (SD 0.73) vs. 2.82mm (SD 0.73). Plaque was present on 8.3% and 9.0% of surfaces, and bleeding on probing remained stable with a mean of 17.4% and 18.0%. None of the parameters were statistically significantly different between groups (p>0.05).Conclusion:Peri-implant health did not differ between OsseoSpeed EV and TX implants. A gain in crestal bone levels was observed in both groups but EV implants indicated an improved primary stability.Although not possible to determine, it cannot be excluded that in three of the four early EV failures, a deviation in the cortical bone preparation may have contributed to the outcome.Experiences from this study led to modifications of the suggested drilling protocol including widening of the spongious bone preparation to facilitate the implant placement within recommended torque value.