Salivary IL-1 beta, 'Red Complex Bacteria' and maintenance frequency as predictors of periimplant crevicular fluid IL-1 beta response in periimplant mucositis

Abstract

OBJECTIVES: This study investigated the association of periimplant crevicular fluid (PICF) IL-1 beta levels with salivary ‘red complex’ periodontopathogen counts, salivary IL-1beta levels, maintenance visit frequency and a cumulative variable, in periodontally susceptible (P) and non-susceptible (NP) subjects with periimplant mucositis. METHODS: 87 healthy partially edentulous subjects under maintenance care were recruited, including 40 with history of chronic periodontitis (periodontally susceptible; P) and 47 without the history (periodontally non-suscpetible; NP). All subjects had at least one implant with periimplant mucositis. Clinical and demographic measures were recorded. IL-1 beta levels in unstimulated whole saliva and PICF were measured by ELISA, respectively. Whereas, the ‘red complex’ bacteria counts in saliva were assessed by real-time PCR. Subjects were scored according to threshold salivary pathogen levels {more than 5 Log (10) counts} and then assigned a ‘Red Complex Score’. Scores were assigned each for quartiles of salivary and PICF IL-1beta levels (1-4) and maintenance frequency (1-3). A cumulative variable C computed as a product of maintenance score, salivary IL-1 beta and ‘Red Complex Score’. Receiver Operating Curves were computed for predicting ‘high (score 4)’ PICF IL-1 beta responders. RESULTS: No significant difference in salivary and PICF IL-1 beta levels as well as periodonpathogen counts was found between the P and NP groups. The ‘Red Complex Score’ (auc=0.758, p=0.010), salivary IL-1beta levels (auc=0.708, p= 0.038) and C values (auc=0.784, p=0.005) were all significant discriminators of the ‘high’ PICF IL-1 beta responders in the NP group, but not in the P group. CONCLUSIONS: The salivary biomarker levels including IL-1 beta, periodontal pathogens and maintenance frequency could not be used to discriminate the ‘high’ PICF 1L-1 beta responders among periimplant mucositis subjects with inherent periodontal disease susceptibility. This finding suggests there may be larger inherent variability in individual host responses to microbial challenge within the disease-susceptible group.