Indian Journal of Dental Research

: 2013  |  Volume : 24  |  Issue : 6  |  Page : 674--677

Hormonal fingerprints: A key to early diagnosis of caries

Priya Verma1, Amitha M Hegde2, R Narayanacharyulu3,  
1 Departments of Pedodontics and Preventive Dentistry; ITS Centre for Dental Sciences and Research, Ghaziabad, Uttar Pradesh, India
2 AB Shetty Memorial Institute of Dental Sciences, Derelakatte, Mangalore, India
3 NGSM Institute of Pharmaceutical Sciences, Paneer, Deralakatte, Mangalore, Karnataka, India

Correspondence Address:
Priya Verma
Departments of Pedodontics and Preventive Dentistry; ITS Centre for Dental Sciences and Research, Ghaziabad, Uttar Pradesh


Background: 6-n-propylthiouracil (PROP) is one of the widely used anti-hyperthyroid drug used for the treatment of grave«SQ»s disease. A medicated tool despite being non-invasive, economical and giving reliable results presented with some difficulties, which became prevalent in our subsequent studies, thus prompting us to formulate a new method for predicting oral health status and diseases like diabetes occurring in India. Aim and Objectives: The current paper would be focusing on the new biological marker-Hormonal Fingerprint that is under trial to predict children for their caries risk susceptibility. Materials and Methods: A total of 250 children were selected of age group 6-16 years and PROP sensitivity test was carried out by placing a strip on the dorsal surface of the subject tongue. The hormonal fingerprint was made by measuring the length ratio of the index and ring finger with the help of digital vernier caliper. Statistical Analysis Used: The statistical method employed to compute the results were Pearson«SQ»s Chi-square test and analysis of variance. Results: Overall results suggested positive correlation between low second-to-fourth digit ratio(2D:4D), i.e. high prenatal androgen levels and high caries index in an Indian population. Conclusion: The research confirms the impact of hormones on human perception of taste and dietary preferences, which in turn influence their caries index and could also extend way beyond it.

How to cite this article:
Verma P, Hegde AM, Narayanacharyulu R. Hormonal fingerprints: A key to early diagnosis of caries.Indian J Dent Res 2013;24:674-677

How to cite this URL:
Verma P, Hegde AM, Narayanacharyulu R. Hormonal fingerprints: A key to early diagnosis of caries. Indian J Dent Res [serial online] 2013 [cited 2022 Jun 30 ];24:674-677
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Full Text

Hormonal fingerprint is a new risk marker that has been used in the study to predict caries risk at a very early stage of life is found to be more stable, reproducible and consistent for each individual.

Research confirms the impact of hormones on human physical and personality traits. The second-to-fourth digit ratio(2D:4D) is sexually differentiated in humans, [1] as for humans, men tend to have lower 2D:4D than women, which sex effect is due to men's greater relative length of the ring finger, in comparison with their index finger. [2] The first mechanism is that common genes Hox A and Hox D that underlie the development of both digits and gonads. [3],[4] Such that the timing of gene regulation leaves a digit ratio that reflects the quantity of androgen produced. The second proposed mechanism is that finger ratio is a function of androgen sensitivity rather than androgen concentration. These sex and individual differences in 2D:4D emerge in-utero at the beginning of the second trimester and seems to be fairly stable during postnatal life. [5] These further lines of evidence have led to the proposal that 2D:4D might be useful as a retrospective, indirect marker for assessing prenatal sex-hormone action, on the body, brain and behavior along with taste perception. The current paper would be focusing on the new biological marker-hormonal fingerprint that is under trial to predict children for their caries risk susceptibility by determining their dietary preferences, taste perception and also to find out the association between the two factors.

 Materials and Methods

A total number of 250 children were selected from both sexes of age group ranging from 6 to 16 years. These children were then divided into tasters and non-tasters (NTs) category after carrying out a 6-n-propylthiouracil (PROP) sensitivity test [Figure 1]. [6] PROP sensitivity test was carried out by placing a filter paper containing PROP on the dorsal surface of the anterior two-third region of the subject tongue for 30 s; the purpose of doing this test was to determine the inherent genetic ability to taste a bitter or sweet substances. [6] The strip was prepared by using Whatman filter paper, that was cut into 2 × 2 cm size and an average amount of the drug impregnated on each strip approximately was 1.6 mg. The hormonal finger print was then recorded by measuring the length ratio of the index finger as well as the ring finger with the help of digital vernier caliper [Figure 2] and [Figure 3] [5],[7],[8] and divide the entire population into high 2D:4D, low 2D:4D and equal 2D:4D digit ratio. A questionnaire was also prepared along with this and given to the children or the care taker to know their dietary habits that will mainly include bitter and dairy products to assess their dietary preferences.{Figure 1}{Figure 2}{Figure 3}


Out of 250 children 79.6% of the population had low 2D:4D ratio, 12.8% to high, 7.8% to equal ratio [Table 1] and [Figure 4]. According to sex the prevalence of tasters and NTs in low 2D:4D ratio group were 88 and 111, 14 and 18 in a high 2D:4D, 6 and 13 in equal 2D:4D group respectively [Table 2] and [Table 3], [Figure 5], male population showed the higher prevalence in the low 2D:4D ratio group whereas female group was dominating among both the other groups further suggesting that overall low 2D:4D ratio were a dominating group, also when comparison was made between taster and NTs group, the prevalence of NTs in all three groups was found to be on the higher side thereby indicating the high prevalence of sweet likers and high caries index of an Indian population due to dietary habits and inclination toward sugar in all the groups, i.e. individuals with high, low and equal 2D:4D ratio. On further analysis, it was found that the prevalence of sweet dislikers was high in taster category and prevalence of sweet liker was high in NTs category, which was highly significant [Table 4], [Figure 6] and [Figure 7]. When the comparison was made between digit ratio and dietary preferences, the prevalence of sweet likers was high in all groups and was highly significant in low digit ratio category [Table 5] and [Figure 8]. The statistical method employed to compute the results were Pearson's Chi-square test and analysis of variance that were found to be highly significant.{Figure 4}{Figure 5}{Figure 6}{Figure 7}{Figure 8}{Table 1}{Table 2}{Table 3}{Table 4}{Table 5}


The 2D:4D ratio has been much spoken and discussed in the medical scenario, but not much information is available as far as dentistry is concerned. Present study shows a strong clinical correlation between digit ratio, taste perception and dietary preferences where 80% of the population is having low digit ratio suggesting of high prenatal testosterone/androgen levels. The finding of the current study is in accordance with Manning, Scutt and Wilson. The same sex difference has also been reported for at least one other mammal, [9] which is also in concurrence with our study. Because of its early emergence, sexual dimorphism in 2D:4D is thought to be influenced by and hence to reflect, prenatal sex hormone regimes. In particular to, high prenatal androgens, low prenatal estrogens or both may produce a low (masculine) 2D:4D digit ratio. [1] These assumptions are partially supported by studies of males and females with congenital adrenal hyperplasia, a condition characterized by the overproduction of prenatal androgens. [10] The NTs were highly prevalent in this category showing that the majority of the population is having a strong liking toward sweets thus making them more prone to oral decays and other diseases of genetic pattern. This finding is in accordance with Derval et al. and Tepper and Ullrich, Tepper et al. [11],[12],[13]


Acting as a predictor, hormonal fingerprint overrides gender, ethnicity and age in explaining the different sensory representations of a same taste stimulus. This research confirms the impact of hormones on human perception of taste and dietary preferences, which in turn influence their caries index and could also extend way beyond it. However, the sample size is too small to be conclusive and would require a bigger sample size to come to more concrete and reliable results. Further the study also eliminates the use of medicated tool in children and replaces it with biological tool that is customized for each individual thus reflecting the individual's preferences that's consequently forming their own health maps.

Clinical relevance

Since the hormonal fingerprint is formed as early as 14 th week of intrauterine life. It can be used as a tool for predicting caries susceptibility through taste perceptions, which could be a breakthrough in neonatal and preventive dentistry to predict the risk factors and implement the new preventive measures. The study also indicates that Indian population is predominated with low 2D:4D ratios having high caries index along with the increased prevalence of sweet likers thereby making the entire population more susceptible to oral diseases. Clinically, it is also important to note that early diagnosis of the risk factors will not only come handy, but also help the clinicians to spread awareness at the community level.

Future scope

At this point, it would be a good idea to suggest that if this hypothesis holds true, it can open doors for ruling our other risk factors in dentistry through estimation of hormonal fingerprints.


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