Buffer capacity, pH, and flow rate in saliva of children aged 2–60 months with Down syndrome

This study measured the flow rate, pH, and buffer capacity of saliva from children with Down syndrome aged 2–60 months. We compared 25 children with Down syndrome with 21 children without Down syndrome. The whole saliva was collected under slight suction and the pH and the buffer capacity were determined using a digital pHmeter. The buffer capacity was measured by titration with 0.01 N HCl. The Down syndrome group demonstrated higher buffer capacity than the control group in the pH ranges of 6.9–6.0, 5.9–5.0, and 4.9–4.0. The flow rate was low in the Down syndrome group. Boys from the Down syndrome group demonstrated higher buffer capacity in the pH ranges 6.9–6.0, 5.9–5.0, and 4.9–4.0 than controls, while girls from the Down syndrome group showed no difference compared with controls. Girls with Down syndrome demonstrated significant difference only in the range of pHi–pH 7.0. Conclusion. These data suggest that the Down syndrome persons present a better buffer capacity, supporting the results observed in several studies which found the low dental caries in persons with Down syndrome.