Association between genetic taste sensitivity, 2D:4D ratio, dental caries prevalence, and salivary flow rate in 6-14-year-old children: a cross-sectional study

Background. The aim of this study was to assess the relationship between genetic taste sensitivity, dietary preferences and salivary flow rate in 6‒14-year-old children for identification of individuals at higher risk of developing dental caries. Methods. A total of 500 children 6‒14 years of age, of both genders, who reported to the Department of Oral Medicine and Radiology, were included. Propylthiouracil (PROP) sensitivity test was carried out and the subjects whose perception was bitter were grouped as tasters, whereas those who were unable to perceive any taste were grouped as non-tasters. The 2D:4D ratio was obtained by measuring the length ratio of index finger to ring finger with the help of a digital Vernier caliper. Evaluation of dietary preferences was carried out using a 24-hour dietary recall and accordingly they were categorized as sweet likers and dislikers. The salivary flow rate was estimated by collecting unstimulated saliva by spitting method. Data were analyzed with Student's t-test and chi-squared test. Results. The results suggested a positive relation between low digit ratio (2D:4D), non-tasters, sweet likers and high caries index among the participants with a highly significant statistical difference (P ≤ 0.000). Tasters had high mean of USSR (0.48) than non-tasters (0.29), which was statistically significant. Conclusion. The present research revealed a positive correlation between all the parameters evaluated. Therefore an individual considered as non-taster by PROP was a sweet liker with low 2D:4D ratio, reduced salivary flow rate and high caries index.