Effects of an experimental diet on parotid saliva and dental plaque pH in institutionalized children

Sixty-six children aged 6-12, permanent residents of a children's home, were placed on a diet during a 45-day experimental period to measure salivary flow-rate, pH of saliva and dental plaque, total concentrations of salivary proteins, inorganic phosphate, bicarbonate, calcium and amylase. The total caloric content, as well as the proportional nutrient and calorie distribution of the foods, were determined and compared with those of the previous habitual diet. After the experimental period, stimulated parotid salivary flow, increased by 40 per cent over the pre-experimental values. Total proteins of saliva and pH of both saliva and dental plaque increased significantly, whereas inorganic phosphate concentration decreased. Concentrations of bicarbonate, calcium and amylase did not differ from those found pre-experimentally. The findings appear to derive from lesser retention and increased hardness of the foods in the experimental diet.