Correlation between crestal bone loss and PPD at teeth and implants: a 5- to 20-year long-term cohort study in patients with treated periodontal disease.

Objective: The correlation between crestal bone loss at teeth and probing pocket depth (PPD) has been established. Whether these findings can also be applied to implants is not known. The objective of this study was to determine the correlation between crestal bone loss and PPD at teeth and implants.

Method And Materials: Thirty-one periodontitis-susceptible patients were rehabilitated with fixed implant-supported single crowns and fixed partial dentures. Each patient was examined over a 5- to 20-year period in a 3- to 6-month strict recall program. At each session, periodontal clinical parameters were recorded at teeth and implants. In addition, standardized periapical radiographs were taken after superstructure insertion (baseline) and then at 1, 3, 5, 10, 15, and 20 years.

Results: The survival rate of implants (94.0%) and teeth (97.3%) did not significantly differ in all patients after 20 years (P = .68). Almost all patients had a PPD ≥ 5 mm at implants and teeth throughout the observation period. The crestal bone loss at implants and teeth increased continuously, especially in patients with advanced periodontitis, without a correlation with PPD. A few patients (n = 5) had a PPD ≥ 5 mm and annual bone loss ≥ 0.2 mm at one implant, with a correlation between bone loss and PPD.

Conclusion: In healthy implants and teeth, moderate crestal bone loss is present without correlation with PPD. A few patients showed progressive crestal bone loss at only one implant, with a correlation with PPD.