Association of Phenylthiocarbamide Taste Sensitivity with Dental Caries, Skeletal Maturity, and Body Mass Index Percentiles in Children Aged 8–12 Years: A Cross-sectional Study

Abstract

Background

Taste perception, shaped by both genetic makeup and environmental influences, plays an important role in dietary habits and overall health. Sensitivity to phenylthiocarbamide (PTC), which is controlled by variations in the TAS2R38 gene, categorizes individuals as either tasters or nontasters. This distinction can affect food preferences and may contribute to differences in susceptibility to dental caries. Research has shown associations between PTC-tasting ability and dental caries, skeletal development, and body mass index (BMI), highlighting its potential usefulness in evaluating caries risk and informing growth-related assessments.

Objective

To evaluate the association of PTC taste sensitivity with dental caries experience, skeletal maturation, and BMI percentiles among individuals classified as tasters and nontasters.

Materials and methods

A total of 96 children between the ages of 8 and 12 were randomly chosen for the study. PTC taste sensitivity was determined using a standardized taste test. Skeletal development was assessed via radiovisiography (RVG) of the middle phalanx. BMI was calculated using standard anthropometric measurements and classified into percentiles based on the IAP Pediatric Growth Charts. Dental caries experience was recorded using decayed, extracted, and filled teeth (deft) and decayed, missing, and filled teeth (DMFT) indices.

Results

Nontasters had significantly more carious teeth than tasters (p-value < 0.001). However, no significant differences in BMI or skeletal maturity were observed between tasters and nontasters (p-value = 0.738) and (p-value = 0.555), respectively.

Conclusion

PTC taste sensitivity may help assess dental caries risk in children. While no significant links were found between PTC sensitivity, obesity, or skeletal maturity, the findings emphasize the importance of taste perception in dietary choices and oral health. Further research is needed to understand the mechanisms linking taste sensitivity to health outcomes.

Clinical significance

PTC testing could help clinicians identify cavity-prone children and tailor preventive strategies, with future research exploring taste-based interventions to improve diet and oral health.

How to cite this article

Dixit A, Saxena A, Verma N, et al. Association of Phenylthiocarbamide Taste Sensitivity with Dental Caries, Skeletal Maturity, and Body Mass Index Percentiles in Children Aged 8–12 Years: A Cross-sectional Study. Int J Clin Pediatr Dent 2026;19(2):190–194.

Introduction

Taste perception is essential to human nutrition, overall well-being, and life quality, and is largely influenced by genetic differences, particularly in how individuals detect bitter tastes. The TAS2R38 gene determines sensitivity to bitter compounds such as phenylthiocarbamide (PTC), categorizing individuals into “tasters,” who experience strong bitterness, and “nontasters,” who find such compounds tasteless or neutral. This genetic variation may impact diet, health, and disease susceptibility.¹

Dental caries, a condition caused by the bacterial breakdown of sugars, is influenced by dietary habits, oral hygiene, and genetic factors.² Nontasters, who are less sensitive to bitterness, tend to favor sweeter, calorie-dense foods, increasing their risk of caries. Their preference for sweet flavors leads to higher sugar intake, which, over time, promotes tooth decay. In contrast, tasters, with their heightened sensitivity to bitterness, may be less likely to consume sugary foods, potentially lowering their caries risk. Understanding these genetic factors could aid in preventing dental caries, particularly in children.³

Eating habits formed early in life can lead to lifestyle diseases such as obesity, which become more difficult to address as children grow older. Obesity rates are increasing globally, regardless of age, and it is now recognized as one of the most pressing public health issues of the 21st century. Furthermore, studies suggest that children with elevated body mass index (BMI) percentiles tend to exhibit faster dental maturation.⁴

A child's growth and development are significantly impacted by diet and nutrition, highlighting their crucial role. Recognizing growth trends is essential in clinical orthodontics, as it plays a key role in making precise diagnoses, planning appropriate treatments, and achieving favorable results. Evaluating both skeletal maturity and dental development is especially critical during the initial phases of orthodontic treatment, particularly when interventions aim to modify growth.⁵ As such, a child's sensitivity to PTC may have a potential impact on their skeletal development.

The link between PTC taste sensitivity and various health factors in children—such as dental caries, body weight, and skeletal growth—highlights the significant role genetics play in shaping dietary choices and related health outcomes. By identifying risk factors such as PTC sensitivity, health professionals could develop personalized prevention strategies that promote healthier lifestyles. Understanding the genetic basis of taste perception offers a pathway for early intervention, helping to reduce the long-term effects of poor dietary habits and associated health risks. This research aims to enhance our ability to prevent health issues through tailored dietary recommendations and interventions.

Materials and Methods

Study Design

Observational, cross-sectional, and an institution-based.

Setting

This study was carried out over a span of 2 months in the Outpatient Department of Pediatric and Preventive Dentistry. During this time, 96 children between the ages of 8 and 12 years, all in the mixed dentition stage, were selected for data collection. Prior to initiating the study, approval was secured from the Institutional Ethical Committee.

Participants

Participants were selected based on specific inclusion and exclusion criteria. The inclusion criteria consisted of children between the ages of 8 and 12, in the mixed dentition phase, whose parents or guardians had given informed consent and who were available for radiographic evaluation of the middle phalanx. The exclusion criteria included children with known genetic disorders, those undergoing orthodontic treatment, children on medications that are known to alter taste perception, and children with permanent dentition.

The initial step was to assess the children's genetic taste sensitivity with PTC test papers provided by Precision Laboratories (Fig. 1). Before administering the test, participants were asked to rinse their mouths with water to clear any residual flavors. The child was then instructed to open their mouth, and the strip was placed directly onto the front part of the tongue, and the PTC strip was placed on the tip and anterior portion of the tongue (Fig. 2), an area rich in filiform papillae. A bitter taste sensation indicated a positive response, categorizing the child as a taster. Conversely, children who reported no bitter taste and described the strip as having a plain or paper-like flavor were identified as nontasters. In cases of unclear or inconsistent responses, the test was repeated to ensure accuracy.

Fig. 1:

Phenylthiocarbamide test paper container used for evaluating taste sensitivity in children (manufactured by Precision Laboratories, United States)

Fig. 2:

Administration of PTC taste sensitivity test in a child participant

A thorough oral examination was performed to evaluate dental caries, following the guidelines established by the World Health Organization (WHO) in 1997 (Fig. 3). The examination involved recording the decayed, missing, and filled teeth (DMFT) in the permanent dentition and the decayed, extracted, and filled teeth (deft) in the primary dentition.

Fig. 3:

Intraoral examination being conducted in a study participant

Skeletal maturation was assessed using the modified method of Rajagopal and Kansal.⁶ Radiovisiography (RVG) images of the middle phalanx were collected and analyzed to determine skeletal age (Fig. 4). Informed consent was secured from the parents or guardians ahead of capturing RVG images. Skeletal age was then compared with the chronological age, which was determined using the child's date of birth. Based on this comparison, participants were categorized as having early, delayed, or normal skeletal maturation.

Fig. 4:

Radiovisiograph image of the middle phalanx of the third finger in a study participant

Each participant's height (in centimeters) and weight (in kilograms) were recorded to calculate their BMI (Fig. 5). The resulting BMI values were then interpreted using percentile classifications based on the growth charts provided by the Indian Academy of Pediatrics.⁷ This allowed for an evaluation of the children's BMI relative to their age and gender.

Figs 5A and B:

(A) Measurement of height in a study participant; (B) Measurement of weight in a study participant

Sample Size Collection

Sample size estimation was carried out with the help of G*Power software (version 3.1.9.7), which indicated that at least 76 participants were required to achieve sufficient statistical validity.

Statistical Analysis

The collected data were organized in Microsoft Excel and subsequently analyzed using SPSS software (version 25.0). The Kolmogorov–Smirnov test was applied to assess the distribution of data, which revealed a non-normal distribution. Descriptive statistics were used, with results expressed as median and interquartile range for continuous variables, and as counts and percentages for categorical variables. Comparisons between groups were conducted using the Mann–Whitney U test for nonparametric data and the Chi-square test for categorical variables. A p-value < 0.05 was considered to indicate statistical significance.

Results

The median age of the study subjects was 9.0 years, with an interquartile range of 8.0–10.0 years. The majority of subjects were 8 years old. There was an equal number of male and female participants. Among the study population, 41.7% were tasters, while 58.3% were nontasters. There was no statistically significant variation in BMI observed between the two groups (p-value = 0.738). The skeletal maturity of tasters and nontasters also did not differ significantly (p-value = 0.555) (Figs 6 and 7). However, the median number of carious teeth was significantly greater among nontasters compared to tasters. Specifically, the median number of carious teeth for nontasters was 6.0 (5.00–8.75), while for tasters it was 3.0 (1.0–4.0), with a p-value < 0.001 (Fig. 8).

Fig. 6:

Comparison of BMI percentiles between tasters and nontasters

Fig. 7:

Comparison of skeletal maturity between tasters and nontasters

Fig. 8:

Comparison of dental caries experience between tasters and nontasters

Discussion

The key finding of this research was the strong association between PTC sensitivity and caries experience. Children identified as nontasters—who exhibit reduced sensitivity to bitter substances such as PTC—demonstrated significantly higher caries prevalence, as reflected by elevated DMFT and deft scores. This aligns with the results of Kulkarni et al.,¹ Dusseja et al.,⁸ and Kulshrestha et al.,⁹ all of whom reported that nontasters are more likely to consume sweeter foods, which is associated with a higher incidence of dental decay due to their higher sugar content. Nontasters tend to favor sweet foods, a known cariogenic factor, and this preference for sweeter foods contributes to increased sugar intake, a well-established predisposing factor for caries.

These findings do not align with those reported in earlier studies by Chung et al.,¹⁰ Mohaus,¹¹ and Arakawa et al.,¹² which did not report a significant link between PTC sensitivity and dental caries risk. Despite the correlation between PTC sensitivity and caries, our study found no significant associations between PTC sensitivity and BMI or skeletal maturity (p-values = 0.738 and 0.555, respectively) suggesting that other factors may have a more substantial influence on these aspects of children's health.

In contrast, some earlier studies, such as those by Saraswathi et al.,¹³ Veluswami et al.,¹⁴ and Kulkarni et al.,¹ reported a significant relationship between PTC sensitivity and BMI. Both of the authors found that nontasters tend to have a higher BMI, potentially due to their preference for sweeter foods that are more caloric, whereas Khan et al.¹⁵ found that an elevated BMI appears to be linked with decreased perception of PTC bitterness.

Our study also found no significant relationship between PTC sensitivity and skeletal maturity, which contrasts with some studies, such as that of Johnston et al.¹⁶ and Kulkarni et al.,¹ which suggested a link between skeletal maturity and PTC sensitivity. The lack of significant findings in this area may suggest that skeletal development does not directly influence PTC sensitivity, or that other variables, such as hormonal changes during puberty, may interact with skeletal maturity in ways not fully captured by our study.

There are some limitations to this study. The cross-sectional design limits the ability to establish causal relationships between PTC sensitivity, caries experience, BMI, and skeletal maturity. Additionally, reliance on subjective PTC tasting may have led to misclassification and bias, which could have affected the accuracy of the results. The findings may not be widely applicable due to the modest sample size. Furthermore, variables such as socioeconomic status, dietary habits, and oral hygiene practices were not included in the analysis, and these factors may significantly influence the outcomes.

Conclusion

PTC sensitivity is strongly associated with dental caries, with nontasters being more vulnerable due to a preference for sweet foods. However, no significant correlation was observed with BMI and skeletal growth.

Future studies should investigate the mechanisms linking PTC tasting ability and caries experience, particularly focusing on how nontasters' dietary preferences for sweet foods may lead to higher sugar consumption and increased caries risk. Additionally, research exploring the impact of interventions aimed at improving taste perception on dietary habits and oral health outcomes could provide valuable insights, especially in children at risk for dental caries. Longitudinal studies with larger, more diverse samples would also help in establishing causal relationships and exploring how taste sensitivity changes over time and influences children's overall health outcomes.

Clinical Significance

Phenylthiocarbamide testing could help identify cavity-prone children and guide personalized dietary and hygiene interventions to enhance oral health outcomes. Further research could focus on how taste-related interventions may improve dietary habits and enhance oral health outcomes in these vulnerable children.

Orcid

Anusha Dixit https://orcid.org/0009-0000-5073-8431

Ashish Saxena https://orcid.org/0000-0001-9846-7095