Association between clinical and microbiologic cluster profiles and peri-implantitis

Purpose: The correlation between associated local factors and peri-implantitis remains unknown. The aim of this study was to investigate the association between the clinical and microbiologic profiles and peri-implantitis to eventually categorize different groups of this disease. Materials and methods: Subjects with at least one implant presenting signs of peri-implantitis were selected. The clinical, radiographic, occlusal, and microbiologic profiles of these infected implants were collected. Cases were classified into five peri-implantitis groups according to potential disease-triggering factors: surgically, prosthetically, biomechanically, purely plaque-associated, and a combination of them. Generalized estimating equations models were used to study differences among the potential risk factors. Cluster analyses were applied to investigate the correlation between clinical and microbiologic profiles and diseased implant samples. Results: Overall, 110 diseased and 121 healthy implants were included. The biomechanically associated group showed higher levels of microbiologic contamination inside the connection; however, the plaque-associated group had a higher level of microbial variety in the peri-implant sulcus. Cluster analyses demonstrated a significant ability to predict the associated factor of peri-implantitis. Moreover, radiographic marginal bone loss and implant width demonstrated the largest influence on the model. Conclusion: While peri-implantitis represents a plaque-induced inflammatory condition, certain local factors might be associated with this biologic complication, as they imply plaque retention. Therefore, disease classification could be further implemented with the associated surgical, prosthetic, and biomechanical factors to better target the etiology.