Page 100 - Peri-implant health: the effect of implant design and surgical procedure on bone and soft tissue stability

CHAPTER 4
There is a statistically significant difference in the mean bone loss calculated between the various roughness groups with a trend for higher bone loss for the rougher implant surface (Table 5). Whether this is of clinical significance remains disputable taking heterogeneity of the studies into account. Furthermore, one should take into consideration a 0.3 to 0.5 mm measurement error when performing radiographic bone assessments.
Hence, a better approach is to compare implants with equal design but only differing in surface topography in prospective randomized controlled trials. Unfortunately, the only available prospective trial147 was excluded because of missing standard deviation, required to do the statistics. The other three studies, albeit of retrospective design, were testing minimally rough surfaces and moderately rough surfaces with similar implant designs. Hence, these three studies were apt for meta-analysis as shown in Figure 4. The minimally rough surface was statistically better in minimizing bone loss. However, the amount of studies is scarce and more research is required to confirm this finding.
■ CONCLUSIONS
Although rough surface implants induce statistically significant more bone loss according to the present meta-analysis, the clinical impact of surface roughness on bone loss is limited in the majority of the papers. The multifactorial cause for bone loss and the heterogeneity of the studies, related to inclusion of risk patients as well as poor data reporting, make it difficult to draw strong conclusions regarding the effect of implant surface roughness on bone loss over time. Nevertheless, independent of surface or implant brand, bone loss above 3 mm occurs in less than 5% of all implants after at least 5 years in function. Moreover, the meta-analysis indicates that co-factors such as smoking or periodontal disease increase the risk for bone loss.
98