Salivary Peroxidase and Buffer Capacity of Parotid Salival in Schoolchildren

The salivary peroxidase is an enzyme that catalyzes the formation of hipothiocyanite (OSCN-) or hipothiocyanite acid, having low toxicity and antimicrobial activity on the saliva. The saliva has a protective buffering capacity that prevents the solubility of mineralized tissues and the erosion of the oral tissues. The purpose of this study was to determine the peroxidase activity and buffer capacity on the stimulated parotid saliva on children with dental cavities and gingivitis.The saliva sample was take it from 16 children, between 9 and 14 years old (8 boys and 8 girls) directly obtained from the parotid excretory duct, the sample size was calculated by 99%CI and 0,078ml/min/gland variance (salivary flow) of pilot test and the selection of the sample was random. The following measurements were made: salivary flow, pH, peroxidase activity, concentrations of bicarbonate and total protein concentrations. We determinate in clinical examination: gingival index by Loe and Silness, plaque index by Loe and Silness, bleeding index by Ainamo and Bay and DMF (decay, missing, filled). The results showed that all the children had dental plaque and gingivitis and 87.5% decay. The result of the saliva sample showed this content: salivary flow 0.75±0.31ml/min/gland, total volume 4.5±1.8ml, pH 8.3±0.7, bicarbonate concentration 61.13±21mM and the protein concentration level was between 100-200mg/dl (87% of children) the salivary peroxidase also showed activity 0,27±0,018A470/min in conditions 1mM H2O2, pH7(25oC). The results showed that the activity of peroxidase and the buffering capacity were not affected in the children with dental cavities and gingivitis.