Microbes, inflammation, scaling and root planing, and the periodontal condition

Biofilms are a complex community of microorganisms characterized by the excretion of an adhesive and protective extracellular matrix, microbe-to-microbe attachment, structural heterogeneity, genetic diversity, and complex community interactions. Bacteria growing in dental biofilms display an increased tolerance to antibiotics and antimicrobial agents, including those used in dentifrices and mouthrinses. The microbial challenge associated with the inflammatory periodontal diseases induces an immediate inflammatory and immune response in the host. The nature and magnitude of the response has an impact on the severity and rate of progression of the periodontal disease. It is this host inflammatory-immune response that ultimately leads to the clinical signs and symptoms of gingivitis and chronic periodontitis. The traditional treatment modality of scaling and root planing (SRP) remains the "gold standard" for the non-surgical management of chronic periodontitis. Even clinically successful treatment has a high probability of pocket reinfection. Re-infection of periodontal pockets results from residual biofilms, increased tolerance of microbes within a dense, mature biofilm to antibiotics, reservoirs of bacteria in calculus, and reservoirs of bacteria within the dentinal tubules of infected root surfaces. Thus, for maximum effect, a combination of scaling and root planing and locally delivered antimicrobials should be considered if non-surgical therapy is the treatment of choice.