Dental caries and periodontal disease are among the most prevalent diseases known to man. Both are associated with the bacteria contained in dental biofilm. Dental biofilm is complex, with a well-organized structure. Up to 500 bacterial species have been identified in dental biofilm. Studies have shown that plaque accumulates rapidly on clinically plaque-free teeth. For oral and systemic health, the development and maturation of dental biofilm should be impeded and the dental biofilm needs to be regularly and meticulously removed. Removal and reduction of biofilm can be by mechanical means or mechanical and chemical means, and disclosing agents enable visual identification of plaque. Current chemotherapeutics in general do not effectively penetrate thick biofilm, underscoring the importance of the identification and rigorous mechanical removal of the dental biofilm.