Page 191 - Peri-implant health: the effect of implant design and surgical procedure on bone and soft tissue stability

also examined how mean bone loss correlated with mean probing pocket depth and mean bleeding on probing. No significant correlation was found between mean bone loss and the prevalence of peri-implantitis. The results showed no significant correlation between mean bleeding on probing and prevalence of peri-implantitis or mean probing pocket depths and prevalence of peri- implantitis. The panel of experts advised in their research directions that the use of the currently available diagnostic tools, reporting mean or median values of diagnostic parameters is not sufficient per se to describe the extent of biologic complications in epidemiologic research. Therefore, future studies should report (1) a case definition that is internationally accepted, (2) validated assessments (repeated measurements, calibrated examiners), (3) baseline registrations for probing pocket depth, bleeding on probing, and bone level, (4) frequency distributions combining the different diagnostic parameters, and (5) percentage of disease according to case definition, based on the implant and patient level. This extensive reporting makes it possible to compare studies and include more studies in meta-analyses. This, in turn, could lead to a more precise estimate of the extent of biologic complications and a smaller prevalence range of peri- implantitis given in the literature.
Clinical Implant Outcome
Initially a total of 196 implants were included in the three clinical studies presented in the thesis (Study III – V). Table 4 gives an overview of all the included implants regarding implant survival and crestal bone level at the latest follow-up visit. Only Study V showed four early failures, possibly caused due to overloading of non- splinted implants. The overall survival of all implants included in this study was 98.0%. This survival rate is comparable with the results described in the systematic reviews (Study I and II). These systematic reviews included respectively 9,457 and 15,695 implants and reported an overall weighted survival rate of respectively 96.9% and 97.3%. This is in accordance with other earlier published RCT’s and systematic reviews.12-14
At the latest follow-up visit the mean crestal bone level for the different study groups of Study III, IV, and V ranged between 0.12 and 0.62 mm. In all groups the median was lower than the mean, indicative that the mean was influenced by a few implants with more extensive bone loss. As previously discussed, the mean is not an adequate measure for peri-implant health or disease. The median,
GENERAL DISCUSSION
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