The 6-n-propylthiouracil (PROP) test is widely used to identify genetic sensitivity to bitter taste, categorizing individuals as super-tasters, medium tasters, or non-tasters, and to explore its potential association with dental caries in children. To assess the relationship between PROP taste sensitivity and dental caries experience among children and adolescents.
Materials and Methods:
Literature search was performed across databases, including PubMed, Scopus, Cochrane CENTRAL, CINAHL via EBSCOhost, and Google Scholar, up to September 2023. Studies investigating association between PROP-based taste sensitivity and dental caries were included. ROBINS-I tool and GRADE were used to evaluate risk of bias and quality of evidence, respectively. Random-effects meta-analyses were conducted; results were expressed as standardized mean differences (SMDs) with 95% confidence intervals (CIs).
Results:
Out of 96 retrieved studies, 17 met inclusion criteria, with 13 contributing to meta-analysis. Included studies exhibited moderate to serious risk of bias. Children classified as non-tasters showed significantly higher dental caries scores at surface level compared to both medium tasters (SMD = 1.27, 95% CI = 0.36–2.17, p = .006, I² = 97%) and super-tasters (SMD = –1.77, 95% CI = –3.11 to –0.43, p = .009, I² = 98%). Overall quality of evidence was rated as very low.
Conclusions:
PROP non-tasters have a greater risk of dental caries. These results highlight the need for preventive strategies and follow-up care for children and adolescents identified as having a higher susceptibility based on taste perception.
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