Journal of Indian Society of Pedodontics and Preventive Dentistry
Journal of Indian Society of Pedodontics and Preventive Dentistry
                                                   Official journal of the Indian Society of Pedodontics and Preventive Dentistry                           
Year : 2021  |  Volume : 39  |  Issue : 3  |  Page : 240--245

Association of serum Vitamin D and salivary calcium and phosphorus levels in 3-11-year-old schoolchildren with dental caries


N Pratyusha, C Vinay, KS Uloopi, Kakarla Sri RojaRamya, P Ahalya, Chigurupati Devi 
 Department of Pedodontics and Preventive Dentistry, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India

Correspondence Address:
Dr. Kakarla Sri RojaRamya
Department of Pedodontics and Preventive Dentistry, Vishnu Dental College, Bhimavaram - 534 202, Andhra Pradesh
India

Abstract

Background: Vitamin D plays an essential role in the formation of healthy teeth, protection against dental caries, and the appropriate secretion of salivary calcium. Salivary calcium and phosphate help in maintaining equilibrium between demineralization and remineralization of teeth. If we know the association between serum Vitamin D and salivary calcium and phosphorus, we may get a clue regarding serum Vitamin D levels which in turn is essential for good oral health. Aim: The aim of this study was to assess the association of serum Vitamin D levels and salivary calcium and phosphorus levels in children with dental caries. Settings and Design: This was a comparative cross-sectional study. Materials and Methods: One hundred children of age 6–11 years, 50 with Decayed, Missing, and Filled Teeth (DMFT) ≥5 (test group) and 50 with DMFT = 0 (control group), were included in the study. Oral examination was carried out and DMFT/deft scores were recorded. Serum 25-hydroxy Vitamin D levels and salivary calcium and phosphorous levels were measured. Statistical Analysis: Independent sample t-test, linear regression analysis, and Pearson correlation test were used for statistical analysis. Results: Children with dental caries have shown lesser mean serum Vitamin D levels (15.37 ± 3.53) than caries-free children (17.26 ± 3.16). Children with decayed teeth have exhibited lower salivary calcium levels (3.92 ± 0.99) than those without caries (4.42 ± 1.37). Conversely, children with dental caries have shown higher mean salivary phosphate levels (6.27 ± 1.74) than caries-free children (5.18 ± 1.47). There is a significant decrease in salivary calcium (P = 0.018) and serum Vitamin D (P = 0.004) with a significant increase in number of decayed teeth. The greater the Vitamin D deficiency, the lesser are the salivary calcium levels observed (P = 0.001). Conclusions: Children with Vitamin D deficiency have lower salivary calcium levels. Vitamin D deficiency and lower salivary calcium levels can be the potential risk factors for the occurrence of dental caries.



How to cite this article:
Pratyusha N, Vinay C, Uloopi K S, RojaRamya KS, Ahalya P, Devi C. Association of serum Vitamin D and salivary calcium and phosphorus levels in 3-11-year-old schoolchildren with dental caries.J Indian Soc Pedod Prev Dent 2021;39:240-245


How to cite this URL:
Pratyusha N, Vinay C, Uloopi K S, RojaRamya KS, Ahalya P, Devi C. Association of serum Vitamin D and salivary calcium and phosphorus levels in 3-11-year-old schoolchildren with dental caries. J Indian Soc Pedod Prev Dent [serial online] 2021 [cited 2021 Nov 29 ];39:240-245
Available from: https://www.jisppd.com/text.asp?2021/39/3/240/330713


Full Text



 Introduction



Dental caries is a serious oral health problem, and children are no exception to this. Newbrun tetralogy well established the fact that diet is a critical component for the occurrence of dental caries. Any alteration in the diet causes nutritional deficiencies which will adversely affect oral health.[1],[2]

Vitamin D is an essential element in the diet. It is also known as the sunshine vitamin as it gets synthesized in the skin. In the current scenario, there is an increased usage of sun-protective measures such as wearing full sleeve clothes, sunscreen lotions, and vegetarianism. Adding to this, Indians have high melanin content due to darker skin complexion that acts as a natural sunscreen. These all factors affect the production of Vitamin D in the body.[3],[4]

There is an increase in the prevalence of Vitamin D deficiency globally, mostly in the Middle East, China, Mongolia, and India.[5] In India, the prevalence of Vitamin D deficiency is 50%–90% in the general population.[4] The US Endocrine Society classified Vitamin D status as deficiency if <20 ng/ml, insufficiency if 21–29 ng/ml, sufficiency if >30 ng/ml, and toxicity if >150 ng/ml.[6] The main causative factors are decreased sun exposure and use of dietary products not fortified with Vitamin D. The Indian Academy of Pediatrics recommends daily Vitamin D supplementation of 400 IU during infancy and 600 IU for 1–18 years of age.[7]

Vitamin D has an essential role in calcium and phosphate homeostasis. It regulates plasma ionized calcium and phosphate levels by acting on intestinal absorption, renal excretion, and mobilization from bone. It promotes bone formation and growth by activating chondrocyte differentiation and increasing serum calcium and phosphate levels.[8]

Generally, the role of Vitamin D in the health of skeletal system is well informed to the public, but its function in the formation of healthy teeth and appropriate secretion of salivary calcium is not well known.[9] It is an established fact that salivary calcium level is influenced by the concentration of serum calcium. Hence, Vitamin D indirectly affects salivary calcium levels. Salivary calcium and phosphate help in maintaining equilibrium between demineralization and remineralization.[10]

It is learned that there is a paucity of literature regarding the effect of serum Vitamin D levels on salivary calcium and phosphate concentration and its indirect influence on dental caries experience in children. Hence, a comparative cross-sectional study was planned to assess the association of serum Vitamin D levels and salivary calcium and phosphorus levels in children with dental caries.

 Materials and Methods



The study design was approved by the Institutional Ethical Committee (VDC/IEC/2017/15). A prior permission was obtained from the school authorities for oral examination of students. The purpose and procedural details of the study were clearly explained and written informed consent was obtained from parents/guardians. All procedures performed were in accordance with the ethical standards of the Institutional Research Committee and Helsinki Declaration.

The study was carried out using multistage sampling technique. Among the primary schools in Bhimavaram town, two schools were randomly selected by the lottery method. The purpose and procedural details of the study were explained to school authorities, parents, and children. A total of 185 children (83 boys and 102 girls) of 6–11 years were screened for the selection (test and control groups) based on Decayed, Missing, and Filled Teeth (DMFT)/deft scores. Out of them, 163 children (76 boys and 87 girls) were selected based on inclusion and exclusion criteria. The parents of all the children were interviewed with prestructured questionnaire to know confounding factors. The questions are directed to get the information on regular dental visits, socioeconomic status, brushing frequency, frequency and type of sugar and milk intake, and the use of multivitamins. The interview was conducted to know the other factors which may influence the outcome of the study.

Parents of 115 children (54 boys and 61 girls) gave the consent. Finally, based on the calculated sample size (n = 100), 50 children (25 boys and 25 girls) with DMFT score more than 5 and 50 caries-free children (25 boys and 25 girls) were included in the study by stratified random sampling. Whereas, children with systemic diseases, those under the medication, and parents reluctant for blood withdrawal were excluded.

Oral examination of all the children was carried out by the investigator using a sterile mouth mirror and probe under proper illumination after removing the food debris from the teeth surfaces, and DMFT/deft scores were recorded.

Five milliliters of unstimulated saliva was collected in a sterile container. Salivary calcium level was analyzed using Arsenazo III reaction and values were noted in mg/dl. The salivary phosphorous level was measured using the ammonium molybdate method and values were noted in mg/dl. Two milliliters of blood was collected, and serum 25(OH) Vitamin D level was measured using fully automated chemiluminescent immunoassay and values were noted in ng/ml.

The obtained data were quantitative and followed a normal distribution. Data were analyzed with descriptive analysis (mean and standard deviation) to know the distribution of the sample in various categories. An independent sample t-test was used for intergroup comparison. Linear regression analysis was used to know the effect of confounding factors on the outcome variables. Pearson correlation test was used to find the association between the variables.

 Results



The mean serum Vitamin D level is lower in the test group (15.37 ± 3.53 ng/ml) when compared to the control group (17.26 ± 3.16 mg/dl), and the difference is statistically significant (P = 0.006). Furthermore, the mean salivary calcium level is lower in the test group (3.92 ± 0.99 mg/dl) compared to the control group (4.42 ± 1.37 mg/dl), and the difference is statistically significant (P = 0.039). Whereas, the mean salivary phosphorus level is higher in the test group (6.27 ± 1.74 mg/dl) than the control group (5.18 ± 1.47 mg/dl), and the difference is not statistically significant [P = 0.266; [Table 1]].{Table 1}

Among the children of 6–7 years, the mean serum Vitamin D level is higher in the control group (18.38 ± 2.51 ng/ml) when compared to the test group (15.31 ± 4.01 ng/ml). The difference is statistically significant (P = 0.014). Whereas, there is no significant difference in mean serum Vitamin D level between the test and control groups among the children of 8–9 years (P = 0.171) and 10–11 years [P = 0.268; [Table 2]].{Table 2}

As the severity of Vitamin D deficiency increased, there is a significant decrease in salivary calcium levels [P = 0.001; [Figure 1]]. The decline in Serum Vitamin D is associated with a significant increase in the number of decayed teeth [P = 0.004; [Figure 2]]. As there is a decrease in salivary calcium, there is a significant increase in the number of decayed teeth [P = 0.018; [Figure 3]]. Regression analysis of prevalidated questionnaire has shown that none of the covariates (number of visits to dentist, frequency of brushing, frequency of dietary sugar consumption, frequency and type of milk intake, and use of multivitamins) have influenced serum Vitamin D level and DMFT score significantly [Table 3] and [Table 4].{Figure 1}{Figure 2}{Figure 3}{Table 3}{Table 4}

 Discussion



There is a dilemma in understanding the interrelation of nutritional deficiencies and dental caries, whether dietary deficiencies lead to dental caries or suffering with dental caries cause nutritional deficiencies. It needs greater insight to unravel this association. It is a known fact that the deficiency of calcium, phosphorus, and Vitamin D is likely to cause dental caries.[11]

Vitamin D plays an essential role in craniofacial development and maintenance of good oral health. Malnutrition and Vitamin D deficiency during the formation of primary and permanent teeth can result in enamel hypoplasia and dental caries.[2] A concentration of 30–40 ng/ml of Vitamin D promotes the cariostatic effect which is due to the antimicrobial properties executed through the induction of peptides such as cathelicidin and defensins.[12] Vitamin D is vital for the absorption as well as metabolism of calcium and phosphorus.[3] Calcium and phosphorus in saliva play a protective role against dental caries. They maintain equilibrium between demineralization and remineralization processes.[10]

When we suspect underlying Vitamin D deficiency as the cause for dental caries, it may not always be possible to assess its levels in children due to the invasive nature of blood test. Hence, if we know the association between serum Vitamin D and salivary calcium and phosphate, we can get a clue to estimate serum Vitamin D status. As the estimation of salivary calcium and phosphate is simple and noninvasive, it can be performed easily in children. This thought process lead us to carry out this study.

Association of serum Vitamin D and dental caries

In the present study, children with dental caries were found to have significantly lower serum Vitamin D levels than caries-free children. This finding is similar to the previous studies where children with S-ECC were found to have relatively lower Vitamin D status compared to caries-free children.[2],[13],[14] Vitamin D reduced the initiation of new carious points, halted the spread of existing carious lesions, and arrested the infective process in decayed teeth.[15] Vitamin D is a promising caries-preventive agent. However, the level of evidence in the reduction of dental caries incidence is low.[16] The results of the present study were contrary to the findings of Dudding et al., wherein they found that the association between dental caries and Vitamin D level was low.[17] The conflicting observations related to Vitamin D and dental caries experience are attributed to the failure in understanding the multifactorial etiological factors involved in the caries process. It was proposed that all the children who were at potential risk for dental caries should get screened for Vitamin D levels.[18] Early identification of underlying deficiency will help in preventing further deterioration of oral health.

Association of serum Vitamin D and salivary calcium and phosphorus

The current study revealed that as serum Vitamin D levels increased, there is a rise in the salivary calcium levels. This fact describes the role of Vitamin D in the absorption and transportation of serum calcium. The interaction of 1,25-dihydroxy Vitamin D with the specific receptor increases the efficiency of intestinal calcium absorption to 30%–40% and phosphorus absorption to approximately 80%. Vitamin D helps in increasing serum calcium levels. This, in turn, increases the salivary calcium level, thereby increasing the remineralization of the tooth surface.[19] Although caries progression is dependent on multiple factors, adequate dietary supplementation of calcium and Vitamin D could add additional benefit in preserving good oral health. The findings of the current study underline the role of Vitamin D in maintaining optimum salivary calcium and phosphate levels.

Association of salivary calcium and phosphorus and dental caries

In this study, children with dental caries demonstrated lower salivary calcium levels than caries-free children. This is in line with the previous literature where caries-free children have more salivary calcium levels than children with caries.[20] Similarly, previous studies revealed a significant association between low levels of salivary calcium and high DMFT scores.[10],[21],[22] Thus, salivary calcium levels significantly influence hard dental tissue defense mechanisms and dental health.[23],[24]

In the present study, the mean salivary phosphorus level is higher in children with dental caries than caries-free children. This was in contrast with the results of a previous study where salivary calcium and phosphorous levels are increased with a decrease in the caries activity of the children.[25] Whereas, few authors have reported that there is no difference in salivary calcium and phosphate levels in children with and without dental caries.[26]

As dental caries is a multifactorial disease, there are numerous factors which influence the occurrence of decay. The known possible confounding factors were addressed in the current research. All the children shared similar characteristics with respect to socioeconomic status, dietary factors, oral hygiene maintenance, frequency and type of milk consumption, additives in the milk, and multivitamin usage. Hence, we assume that none of the confounding factors affected the outcome of serum Vitamin D levels and DMFT scores.

To summarize the key observations of the study, as the serum Vitamin D levels decreased, there is an increase in salivary calcium and phosphate levels. Children with more number of decayed teeth were found to have lower levels of calcium and Vitamin D. The findings of the present study opens the scope for well-designed prospective clinical trials, to demonstrate whether treating Vitamin D deficiency could influence caries experience.

Being a pediatric dentist, we have an opportunity to identify several underlying systemic conditions by thorough examination of the oral cavity. Imbalance in the levels of salivary calcium and phosphorus can be considered as one of the risk factors for the occurrence of dental caries. In children with multiple decayed teeth, it is worth for a clinician to suggest the analysis of salivary calcium and phosphate, which also gives a vague clue of serum Vitamin D levels. In the present study, most of the children have Vitamin D deficiency, but none were diagnosed earlier. Pediatric dentists have scope to identify and refer such children to a pediatrician for further treatment. It is common to come across Vitamin D-deficient children, but early identification is essential for preventive care.

 Conclusions



From the observations of the study, the following conclusions are drawn; children with decayed teeth have lower salivary calcium levels than their normal counterparts. Children with severe Vitamin D deficiency have more number of decayed teeth. However, both children with and without decayed teeth have Vitamin D deficiency. The concentration of serum Vitamin D has a direct influence on salivary calcium levels. As serum Vitamin D levels decreased, there is a decline in salivary calcium concentration.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Bener A, Al Darwish MS, Tewfik I, Hoffmann GF. The impact of dietary and lifestyle factors on the risk of dental caries among young children in Qatar. J Egypt Public Health Assoc 2013;88:67-73.
2Schroth RJ, Rabbani R, Loewen G, Moffatt ME. Vitamin D and dental caries in children. J Dent Res 2016;95:173-9.
3Parthasarathy P, Priya V, Gayathri R. Relationship between Vitamin D and dental caries-review. J Pharm Sci Res 2016;8:459-60.
4Ritu G, Gupta A. Vitamin D deficiency in India: Prevalence, causalities and interventions. Nutrients 2014;6:729-75.
5van Schoor N, Lips P. Global overview of Vitamin D status. Endocrinol Metab Clin North Am 2017;46:845-70.
6Holick MF, Binkley NC, Bischoff-Ferrari HA, Gordon CM, Hanley DA, Heaney RP, et al. Evaluation, treatment, and prevention of Vitamin D deficiency: An endocrine society clinical practice guideline. J Clin Endocrinol Metab 2011;96:1911-30.
7Khadilkar AV, Sayyad MG, Sanwalka NJ, Bhandari DR, Naik S, Khadilkar VV, et al. Vitamin D supplementation and bone mass accrual in underprivileged adolescent Indian girls. Asia Pac J Clin Nutr 2010;19:465-72.
8Holick MF. Vitamin D deficiency. N Engl J Med 2007;357:266-81.
9Schroth RJ, Lavelle C, Tate R, Bruce S, Billings RJ, Moffatt ME. Prenatal Vitamin D and dental caries in infants. Pediatrics 2014;133:e1277-84.
10Fiyaz M, Ramesh A, Ramalingam K, Thomas B, Shetty S, Prakash P. Association of salivary calcium, phosphate, pH and flow rate on oral health: A study on 90 subjects. J Indian Soc Periodontol 2013;17:454-60.
11Shelling DH, Anderson GM. Relation of rickets and Vitamin D to the incidence of dental caries, enamel hypoplasia and malocclusion in children. J Am Dent Assoc 1936;23:840-6.
12Shaker JL, Deftos L. Calcium and Phosphate Homeostasis. In: Feingold KR, Anawalt B, Boyce A, Chrousos G, de Herder WW, Dhatariya K, et al., editors. Endotext. South Dartmouth (MA): MDText.com, Inc.; 2000. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279023/. [Last Updated on 2018 Jan 19].
13Schroth RJ, Levi JA, Sellers EA, Friel J, Kliewer E, Moffatt ME. Vitamin D status of children with severe early childhood caries: A case-control study. BMC Pediatr 2013;13:174.
14Deane S, Schroth RJ, Sharma A, Rodd C. Combined deficiencies of 25-hydroxyvitamin D and anemia in preschool children with severe early childhood caries: A case-control study. Paediatr Child Health 2018;23:e40-5.
15Mellanby M, Pattison CL. The action of vitamin d in preventing the spread and promoting the arrest of caries in children. Br Med J 1928;2:1079-82.
16Hujoel PP. Vitamin D and dental caries in controlled clinical trials: Systematic review and meta-analysis. Nutr Rev 2013;71:88-97.
17Dudding T, Thomas SJ, Duncan K, Lawlor DA, Timpson NJ. Re-examining the association between Vitamin D and childhood caries. PLoS One 2015;10:e0143769.
18Brown T, Creed S, Alexander S, Barnard K, Bridges N, Hancock M. Vitamin D deficiency in children with dental caries-a prevalence study. Arch Dis Child 2012;97:A103.
19Lips P. Vitamin D physiology. Prog Biophys Mol Biol 2006;92:4-8.
20Sejdini M, Meqa K, Berisha N, Çitaku E, Aliu N, Krasniqi S, et al. The effect of Ca and Mg concentrations and quantity and their correlation with caries intensity in school-age children. Int J Dent 2018;2018:2759040.
21Sewón LA, Karjalainen SM, Söderling E, Lapinleimu H, Simell O. Associations between salivary calcium and oral health. J Clin Periodontol 1998;25:915-9.
22Rajesh KS, Zareena, Hegde S, Arun Kumar MS. Assessment of salivary calcium, phosphate, magnesium, pH, and flow rate in healthy subjects, periodontitis, and dental caries. Contemp Clin Dent 2015;6:461-5.
23Dogra S, Bhayya D, Arora R, Singh D, Thakur D. Evaluation of physio-chemical properties of saliva and comparison of its relation with dental caries. J Indian Soc Pedod Prev Dent 2013;31:221-4.
24Laine MA, Tolvanen M, Pienihäkkinen K, Söderling E, Niinikoski H, Simell O, et al. The effect of dietary intervention on paraffin-stimulated saliva and dental health of children participating in a randomized controlled trial. Arch Oral Biol 2014;59:217-25.
25Singh S, Sharma A, Sood PB, Sood A, Zaidi I, Sinha A. Saliva as a prediction tool for dental caries: An in vivo study. J Oral Biol Craniofac Res 2015;5:59-64.
26Bagherian A, Asadikaram G. Comparison of some salivary characteristics between children with and without early childhood caries. Indian J Dent Res 2012;23:628-32.