Page 174 - Peri-implant health: the effect of implant design and surgical procedure on bone and soft tissue stability

CHAPTER 7
at t1 as dependent variable showed that the factors “bone level at t0” and “implant position posterior” had a significant effect on the mean bone level. A posteriorly placed implant reduced the mean bone level with 0.21 mm compared to an anteriorly placed implant. However, this very small estimate with the small range of the confidence limits makes this difference clinically irrelevant. No significant effect on the bone level at t2 was found for the factors “bone level at t0,”“implant type,” and “implant position.”
The overall mean probing pocket depth at t2 was 3.15 mm (SD 0.88, range 1.50– 5.25), with an overall mean bleeding on probing of 0.20 (SD 0.26, range 0.00–0.75), and an overall mean plaque score of 0.22. The linear mixed-model analysis (Table 3) with probing pocket depth at t2 as dependent variable showed no significant impact for the factor “implant type” on probing pocket depth (Table 3). However, this analysis showed a significant impact for the factor “implant position” in favor of the posterior implant with an estimate pocket reduction of 0.338 mm, although this difference is significant it seems to be clinically irrelevant. A logistic regression analysis with bleeding on probing and plaque as dependent variables showed that “implant type” or “implant position” had no significant impact on the odds at t2.
Prevalence of peri-implantitis
The maximum bone loss calculated at t2 compared to t1 (initial remodeling) was 1.63 (Table 2). For 74 implants combined data were available at t2 for bone level, probing pocket depth as well as bleeding on probing. When bone level <2 mm in combination with the absence of bleeding on probing and/or suppuration is considered as success, only one implant did not fulfill these criteria, resulting in a success of 98.6% (Table 4). Moreover, none of these implants showed bone levels ≥3 mm apical of the most coronal portion of the intraosseous part of the implant and/or probing depths ≥6 mm. It could be stated that the incidence of peri-implantitis in the study population is 0% according to the 2017 Consensus report of the World Workshop on the Classification of Periodontal and Per-Implant Diseases and Conditions.13
172