A critical review on the association of hyposalivation and dental caries in children and adolescents

The purpose of this critical review is to assess if children and adolescents with hyposalivation are more affected by dental caries than those with normal flow rate. A literature search was performed using keywords and MeSH terms related to hyposalivation and dental caries in the Medline/PubMed, Web of Science, Cochrane Library, Scopus, LILACS/BBO databases and in gray literature without language or date restrictions until March 2022. Observational studies that accessed the presence of dental caries in patients up to 18 years-old with hyposalivation and compared with a control group (normal salivation rate) were considered eligible. The results from search were imported to EndNote Web, where duplicates were removed followed by title/abstract and full text analysis. A total of 12,236 non-duplicated studies were found and 14 fulfilled the criteria and were included in the present review, 9 cross-sectional and 5 cohorts. Stimulated salivary flow rates were assessed in 3644 participants, aged 3–17 years. Three cohort and three cross-sectional studies observed association between low salivary flow rates and the presence of dental caries, while the other 9 included articles did not verify this association. However, the absence of a standard criteria for the hyposalivation classification in young patients was observed and brough light to this important limitation among the studies. The salivary flow rate estimation for caries risk assessment must be the target of further studies to make possible and reliable, homogeneous, and unbiasedly assessment of the association between hyposalivation and dental caries in young patients. •There is an absence of a validated hyposalivation parameter in the literature for children and adolescents.•Well-conducted clinical studies with robust data are lacking, since there is no consistent definition of hyposalivation for this age group.•It is not possible to reliably assess the relationship between hyposalivation and the presence of dental caries lesions in this age group.