Clinical findings and history of bone loss at implant sites

Objectives: The aim of the present study was to evaluate whether clinical findings at implant sites are relevant as screening tests for a history of marginal bone loss.

Material and methods: 427 patients provided with implant-supported reconstructions 9 years earlier were evaluated clinically (probing pocket depth (PPD), bleeding on probing (BoP)) and radiographically. A history of bone loss was confirmed through baseline documentation. Diagnostic accuracy was evaluated through receiver operating characteristic curves and multi-level regression analyses. Results were expressed as sensitivity/specificity, area under the curve, and odds ratios.

Results: While the sensitivity of PPD in regard to bone loss was low, specificity was generally high. Multi-level modeling revealed that each additional millimeter of PPD corresponded to an additional bone loss of 0.30 mm (95% CI 0.27; 0.33). The sensitivity of BOP in regard to bone loss >2 mm was 80.9% (95% CI 73.9; 86.7), while the specificity was 42.2% (95% CI 39.6; 44.8).

Conclusions: Clinical parameters at implant sites obtained at a single time point were associated with a history of marginal bone loss. While BoP demonstrated a high level of sensitivity, the sensitivity of PPD was generally low. The present data suggest that BoP is a relevant screening test for history of bone loss.