Clinical and microbiological findings in patients with peri‐implantitis: a cross‐sectional study

OBJECTIVE: The aim of this study was to analyze clinical and microbiological characters in subjects and implants affected and not affected by peri-implantitis. Additionally, same features were analyzed also intra-individually, comparing healthy and diseased implants within the same subject. MATERIALS AND METHODS: A total of 534 patients who received at least 1 implant and coming to routine check-up or spontaneous visits at the University of Valencia were recruited. Clinical parameters including Bleeding on probing (BoP), Probing pocket depth (PPD), and Pi were screened. Samples for microbiological analysis were obtained from three locations: peri-implant sulci (PIS), inner parts of the implant connections (I), and gingival sulci of neighboring teeth (GS). Quantitative real-time PCR was performed for total counts of 10 microorganisms. RESULTS: A total of 534 patients with 1507 dental implants were analyzed. The prevalence of peri-implantitis was found 10.3% for patients and 7.3% for implants. Higher percentage of healthy periodontal subjects were found in the non-peri-implantitis group. The analysis within the 53 patients affected by peri-implantitis revealed that the implants affected by peri-implantitis presented a higher percentage of plaque, BoP, and number of implants presenting <2 mm attached gingiva. Additionally, more cemented crowns and implants inserted in bone-augmented sites were found among the diseased implants. The microbiologic analysis presented no relevant differences between the analysis at the peri-implant sulcus (PIS) and the connections inside the abutments surfaces (PI). The microbial composition at the neighboring teeth (GS) resembled the composition found at the PIS with a high frequency of Pg, Tf, Pi, PM, and Ec. CONCLUSIONS: The results of this study seem to indicate that inadequate oral hygiene and the presence of bleeding from the gingiva/mucosa in patients with dental implant were associated with an higher prevalence of peri-implantitis; moreover, in the patients affected by peri-implantitis, the lack of sufficient height keratinized mucosa (<2 mm) and bone regenerative procedures at implant level were also associated to higher prevalence of peri-implantitis as well.