Possible Determinants of Peri-implant Tissue Health and Disease

Objectives: This ongoing observational study aims to investigate conventional clinical parameters and modified periodontal indices as possible risk predictors for long-term peri-implant tissue health.
Methods: Patients with implant supported dental restorations, ≥1yr in function, were recruited. Exclusion criteria were uncontrolled systemic diseases, systemic antibiotics (≤3 months), chronic NSAIDs. Self-reported health problems, medications, periodontal disease history, smoking status were documented. Implant location, restoration type, years in function were recorded. Clinical examination was conducted to diagnose peri-implant tissue status. Univariate and multivariate analyses were conducted for potential determinants in relation to diagnosis.
Results: Sixty-one patients (61±2 yrs old; 35 males; 80 implants [8±1 yrs function]) were recruited. History of periodontal disease, smoking, and diabetes were reported by 20 (33%), 18 (30%), 3 (5%) participants, respectively. 24 (39%) participants were compliant with supportive periodontal therapy. 13(21%) and 12 (20%) patients were on medications for hypothyroidism and cancer prevention. 32 (40%) and 48 (60%) implants were localized in mandible and maxilla. 15 (19%), 23 (29%) and 42 (52%) implants were diagnosed as healthy, mucositis and peri-implantitis, respectively. Thread exposure, probing depth, bleeding on probing (BoP), and modified PMA index were in agreement in detecting health versus disease (p≤0.012). These clinical parameters and suppuration were also in agreement with peri-implantitis severity (p≤0.005). Thread exposure was the only parameter differentially detecting mucositis severity (p≤0.002). Gender (female/male; p=0.023), location (mandible/maxilla; p=0.04) and BoP (absence/presence; p=0.04) were specific to health diagnosis while medications for hypothyroidism (p=0.01) and cancer reoccurrence (p=0.02) were correlated with peri-implantitis severity.
Conclusions: Within the limits of this study, clinical parameters and modified periodontal indices are useful to differentiate peri-implant health from disease but are limited in differentiating mucositis severity. Gender and anatomical location are factors to consider as risk predictors while systemic medications should be further explored.