A comparison of the acid-base metabolisms of pooled human dental plaque and salivary sediment.
The acid-base metabolisms of the mixed bacteria in pooled dental plaque and salivary sediment sampled from the same subjects were compared in vitro. Plaque at a suspension concentration of 8.3 per cent (v/v) was found to produce pH responses like those of sediment at 16.7 per cent (v/v) with all substrates and under all incubation conditions tested. The substrates examined included several carbohydrates (glucose, sucrose and starch) and several nitrogenous substrates (urea, arginine and the arginine peptide glycyl-glycyl-lysyl-arginine also called sialin). Also examined were the effects of endogenous substrates and of salivary supernatant and fluoride. A difference in suspension concentration was necessary to achieve similarity in pH response which was attributed to the presence of more non-viable epithelial cells in sediment than in plaque. Under these conditions, salivary sediment showed a slightly greater buffering capacity than plaque, a difference that was not evident if salivary supernatant was present. It was clear from this study that salivary sediment and pooled dental plaque from the same subjects have similar acid-base metabolisms and that the more abundant and readily available sediment could be used to study such metabolism in dental plaque.
D001120:Arginine / Q000378:metabolism; D050260:Carbohydrate Metabolism; D003773:Dental Plaque / Q000378:metabolism*; D005459:Fluorides / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D012463:Saliva / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism; D014508:Urea / Q000378:metabolism
D012794:Sialic Acids; D014508:Urea; D001120:Arginine; D005459:Fluorides