RESUMEN
OBJECTIVES: The aim of this study was to assess the microbiological and clinical outcomes of immediate implants placed in chronically infected sockets for rehabilitation with fixed full-arch mandibular prostheses. MATERIAL AND METHODS: Fourteen individuals (mean age 60.14 ± 7.69 years) were enrolled in this investigation and followed up until 8 months of function. Microbiological (microbial count and profile) and clinical (probing depth, clinical attachment level, bleeding on probing, and bone resorption) parameters were conducted before teeth extraction (T0 - baseline) and after 4 (T1 ) and 8 (T2 ) months of loading. Thirty-nine microbial species including periodontopathogenic species and Candida spp. were detected and quantified by DNA checkerboard analysis. RESULTS: Moderate to high levels of pathogenic and non-pathogenic species were found colonizing teeth and implant-related sites. No significant differences in total or individual microbial counts and microbial profile were found over time (P = 0.4929). Probing depth values from teeth (T0 : 3.05 ± 1.45) were significantly higher when compared with implants (T1 : 1.81 ± 0.56; T2 : 1.66 ± 0.53; P < 0.0001). High percentages of bleeding sites were found for both teeth and implants, with the highest values recorded for teeth (P < 0.05). No significant differences were detected comparing marginal bone resorption over time. CONCLUSIONS: Total and individual counts of target species did not differ between teeth and implants for 8 months of investigation. The mean proportions of pathogenic and non-pathogenic species remained unaltered, and no clinical complications were reported over time. Data obtained suggest that immediate loading of complete mandibular prostheses retained by implants placed immediately after extraction may be a viable treatment option for edentulous individuals with previous history of periodontal disease.