ULTRACYTOCHEMICAL LOCALIZATION OF HYDROGEN-PEROXIDE PRODUCTION BY DENTAL PLAQUE BACTERIA

This study looked for evidence of in vitro hydrogen peroxide (HP) synt hesis in human dental plaque, using an ultracytochemical technique tha t included incubation in a CeCl3-rich medium. Supragingival dental pla que was obtained from periodontally healthy individuals and subgingiva l dental plaque from human periodontal disease sites. Specificity of t he cytochemical reaction was demonstrated using catalase (as HP scaven ger). HP production was indicated by an electron-dense precipitate loc alized at the cell envelope of unidentified Gram-positive and Gram-neg ative bacteria in both supra- and subgingival samples. The urtracytoch emical reaction localized the HP production primarily to the plasma me mbrane and periplasmic space. (C) 1998 Elsevier Science Ltd. Ail right s reserved.