Relationship between Unstimulated Salivary Flow Rate and Saliva Composition of Healthy Children in Taiwan

Background: Saliva is one of the most important factors in regulating oral health, withflow rate and composition changing throughout development and during disease.In view of the shortage of data, the present study aimed to shed light onthe relationship between unstimulated salivary flow rate and saliva compositionof healthy children in Taiwan.Methods: Forty-four normal, healthy children from 3-14 years of age were divided intothree age groups: pre-school, elementary school and junior-high school. Allparticipants received salivary flow rate, pH and saliva composition analysisunder unstimulated conditions. One-way ANOVA and Pearson’s correlationwere used. Statistical significance was set at p < 0.05.Results: Our results suggest that, under unstimulated conditions, the salivary flow rateof the elementary school group was greater than that of the pre-school group(p < 0.05). No difference in pH was found among the three groups. Intergroupsalivary calcium, phosphorus and amylase did not reach statistical difference.As the flow rate increased, the pH increased (r = 0.364, p < 0.05)but the protein level decreased (r = –0.473, p < 0.05). In addition, salivaryprotein was positively correlated to age (r = 0.479, p < 0.05) and negativelycorrelated to pH (r = –0.361, p < 0.01).Conclusion: Age-related increase in the unstimulated salivary flow rate of pre-school andelementary school groups was noted. As the flow rate increased, the pHincreased but the protein level decreased. The information obtained mayserve as reference values for the growing interest in saliva as a diagnostictool, especially monitoring those with neurological or oral motor dysfunction.