Evaluation of dental age in protein energy malnutrition children.

BACKGROUND: Knowledge of dental age is very essential for a dental practitioner in planning treatment and it is a supplementary source of information for Pediatrician, Orthopedician and Endocrinologist. There are few studies in the literature about the comparison of dental with chronological age in protein energy malnutrition children (PEM). Accordingly, the aim of this study was to evaluate and compare dental age and chronological age in PEM children. AIMS AND
OBJECTIVE: To determine and compare dental age and chronological age in PEM children.
METHODS: A total of 100 PEM children within the age range of 6-12 years were selected. Chronological age was recorded using date of birth. Dental age was assessed by Demirjian's method using orthopantomogram. Comparison of two ages was done using the unpaired Student's t-test and Pearson's correlation coefficient.
RESULTS: Dental age was retarded compared to chronological age, and the difference was statistically significant (P < 0.001). The correlations between two ages were positive in both sexes.
CONCLUSION: Dental age was delayed in our sample of 100 PEM children. Dental age can be considered as variable for diagnosing growth retardation in PEM children. Further studies are required to support our findings.

Growth is an essential feature of the life of a child that distinguishes him or her from an adult. The process of growth starts from the time of conception and continues until the child grows into a fully mature adult. Growth denotes a net increase in the size or mass of tissues, whereas development specifies maturation of functions.[1] Hereditary, functional, environmental, nutritional, sexual, metabolic, social, emotional and cultural factors affect growth and development greatly.[2] Protein-energy malnutrition (PEM) refers to “an imbalance between the supply of protein and energy and the body's demand for them to ensure optimal growth and function” It is a major public health problem in India. It affects particularly the preschool children (<6 years) with its dire consequences ranging from physical to cognitive growth and susceptibility to infection. This affects the child at the most crucial period of time of development, which can lead to permanent impairment in later life. PEM is measured in terms of underweight (low weight for age), stunting (low height for age) and wasting (low weight for height).[3]

Studies have demonstrated that child malnutrition is associated with several health problems.[45678] When analyzing the consequences of malnutrition to oral health, some studies have associated malnutrition with a higher prevalence of dental caries,[6] as well as dental malformations[7] and soft tissue injuries.[91011] Nevertheless, even though some authors have found a significant adverse effect of malnutrition on the growth and development of facial bones of children[1213] and on the development of skeletal muscles[14] (demonstrated by reduced measures of the length of the skull base, height of the jaw,[12] width of the maxilla and mandible, lower face height[13] and dental and skeletal ages).[15]

The development and eruption of the teeth are part of the child's total development. Tooth development is a useful measure of maturity since it represents a series of recognizable events that occur in the same sequence from an initial event to a constant endpoint. Estimation of dental age is based on the rate of development and calcification of tooth buds and their progressive sequence of eruption in the oral cavity. The tooth calcification provides a valuable indicator of dental age and serves as an index of the maturation of the child. Dental formation of calcification, which is a continuous developmental process, should be considered a better measure of physiological maturity than dental emergence. Several methods have been developed in order to assess the dental age according to the degree of calcification observed on permanent teeth. One such widely used method is that given by Demirjian, Goldstein and Tanner based on a large number of Canadian children.[16]

There are few published data about the affect of growth retardation on dental maturity in children with PEM. Accordingly, the current study was planned to evaluate and compare dental age and chronological age in children with PEM.

Materials and Methods

The children were selected from the outpatient Department of Pedodontics and Preventive Dentistry. Prior to the commencement of the study ethical clearance was obtained from the Ethical Clearance Committee of the College. The nature of the study was explained, and informed consent was obtained from the parent of the patient. Sample sizes of 100 PEM children were selected between the age group of 6 and 12 years. Children undergoing treatment for PEM were excluded from the study. Armamentarium for the study included orthopantomograms (OPG), weighing machine, stadiometer, and X-ray viewer.

Selection criteria of the sample: PEM is determined using Waterlow established classification for malnutrition.[17] Instead of using just weight for age measurements, the classification established by Waterlow combines weight-for-height (indicating acute episodes of malnutrition) with height-for-age to show the stunting that results from chronic malnutrition.[18]

The measurement of weight was done by using bathroom scale for weight records nearest to 0.1 kg. The child was weighted with minimum clothes without touching anything with 500 gram was subtracted from the total weight to compensate for underneath clothes.[19]

The measurements of height was done by using the ordinary measuring tape fixed at the wall and the child standing up after removing the shoes with feet parallel to each other and pointed forward and the back is straight in upright position. The knee was straight, and the head was in position that Frankfort plane (the line between the lower border of the orbit and the upper margin of the external auditory meatus) was horizontal.[19]

Protein energy malnutrition is diagnosed in accordance with Waterlow classification [Table 1].[18]

Table 1

Water flow classification of PEM

The child diagnosed with PEM was included under the study.

The chronological age was recorded the actual date of birth either stated by the parents or guardians or as per school records.

An OPG was obtained for each child to determine the dental age. Interpretation of the radiographs was carried out with the help of an X-ray viewer.

Determination of dental age was based on the rate of development and calcification of tooth buds. Dental age estimation was done using Demirjian's method[20] considering seven permanent left mandibular teeth from the central incisor to II molar (If any tooth was congenitally missing, contralateral tooth was considered). Demirjian et al.,[19] divided tooth development into eight developmental stages from A to H.

Demirjians tooth mineralization (developmental) stages [Figure 1] are as follows:

Figure 1

Demirjian's tooth calcification stages

Stage A: Beginning mineralization of separate cusps

Stage B: Fusion of cusps

Stage C: Beginning of dentinal deposits is seen

Stage D: Crown formation completed down to the cemento-enamel junction

Stage E: The root length is less than the crown height

Stage F: The root length is equal to or greater than crown height

Stage G: The walls of the root canal are parallel and its apical end is still partially open

Stage H: The apical foramen is completed.

Each tooth was assigned a score based on its developmental stage [Tables 2 and 3]. The sum of seven individual scores gives maturity score, which is converted into dental age using conversion chart [Tables 4 and 5].

Table 2

Self-weighted scores of dental stages of 7 teeth (mandibular left side) in boys

Table 3

Self-weighted scores of dental stages of 7 teeth (mandibular left side) in girls

Table 4

Conversion of maturity score to dental age: For boys

Table 5

Conversion of maturity score to dental age: For girls

Procedure of dental age estimation

Orthopantomograms [Figure 2] were analyzed for the developmental stages of all the 7 left permanent mandibular teeth as per Demirjian's method [Figure 1]. The developmental stage of each tooth was assessed and then each tooth was given a score according to its stage of development using the score table [Tables 2 and 3]. Adding seven individual scores from permanent central incisor to 2nd permanent molar gives a maturity score, it will be converted into dental age using conversion chart [Tables 4 and 5].

Figure 2

Orthopantamogram

Maturity score = developmental scores of 31 + 32 + 33 + 34 + 35 + 36 + 37.

[31: Left mandibular central incisor, 32: Left mandibular lateral incisor, 33: Left mandibular canine, 34: Left mandibular 1st premolar, 35: Left mandibular 2nd premolar, 36: Left mandibular 1st molar, 37: Left mandibular 2nd molar].

The obtained data were subjected to statistical analysis. The chronological age and dental age were compared using the unpaired Students t-test and Pearson's correlation coefficient.

Results

The study comprised a total of 100 PEM children within the age group of 6–12 years. In the total sample, 61 were males, and 39 were females. Dental age estimation was done using Demirjian's method.

The mean chronological and dental ages in both sexes has been tabulated in Table 6.

Table 6

Mean chronological age, dental age and bone age of females and males

In females [Table 7] chronological ages were higher compared to dental ages and the difference was statistically significant. The correlation between chronological age and dental age were positive and statistically significant [Table 8].

Table 7

Comparison of chronological age and dental age in females

Table 8

Correlation between chronological age and dental age in females

Similarly in males [Table 9] the chronological ages were advanced compared to dental ages and the difference was statistically significant. The correlation between chronological age and dental age were positive and statistically significant [Table 10].

Table 9

Comparison of chronological, dental age and bone age in males

Table 10

Correlation between chronological age and dental age in males

Discussion

Dental age is very important in dentistry and medicine. It is very important for the dental surgeon to formulate a treatment plan and useful for the pediatrician, orthopedician and endocrinologist as a source of complementary information. Therefore, this study was undertaken to determine and compare the dental and chronological age in PEM children.

Dental age has often been used to study the somatic maturity. Eruption and calcification of dental tissues have been used to determine dental age. Tooth calcification is superior to tooth emergence because emergence of a tooth a fleeting event and its precise time is difficult to determine, whereas calcification is a continuous process that can be assessed by permanent records such as X-ray films.[16] In the present study, dental age estimation was done using Demirjian's method. Hägg and Matsson[21] compared the reliability of three different dental age assessment methods and concluded that the method described by Demirjian and Goldstein affords a high degree of reliability and precision. Nanda and Chawla,[22] Hegde and Sood[23] applied Demirjian's method on Indian population and found the accuracy of Demirjian's method when applied to the Indian population.

There are many studies which proved the effect of growth disorders on dental maturity. Our study was undertaken to assess the effect of PEM on dental maturation. In our study, dental age was reduced compared to chronologic age in both males and females. The results of our study are in agreement with those of Vallejo-Bolaños and España-López[24] Takano et al.,[25] Keller et al.[26] and Sarnat et al.[27] Vallejo-Bolaños and España-López[24] discovered a delay in dental age and bone age in 54 familial short statured children. Sarnat et al.[27] conducted a study on 19 patients with growth hormone deficiency and 13 patients with Laron type dwarfism and discovered a delay in dental age of 1.8 and 1.7 years respectively for these two disorders.

Alvear et al.[28] studied 40 preschool children who had been admitted to hospital in infancy with PEM Growth measurements were made over a period of 4–6 years and bone age was determined in a subgroup through wrist roentgenograms the results showed a delay in bone maturation.

Nakamoto et al.[29] studied the effect of PEM on the growth of molar and incisor tooth germs they found significant differences between control and malnourished groups in the weights and calcium contents of both tooth germs. The data point to the importance of the effect of the nutrient deficiency on the critical growth period of an oral structure.

In our findings, the co-relationships between dental age and chronological age were positive in both sexes. We found similar results in other studies such as Vallejo-Bolaños and España-López,[24] Green[2] Hegde and Sood[23] Prabhakar et al.,[16] who also discovered positive correlations between dental age, bone age and chronological age. Many previous authors have studied on the corelationships between biological ages and concluded that various growth indicators are positively correlated.

Conclusion

Dental age was delayed in our sample. Our study showed the affect of PEM on dental maturation. Dental age, as opposed to chronological age, is important to know the maturation of various tissue systems and it is useful in dentistry to arrive at definite treatment plan and its additional source of information in the field of pediatrics, orthopedics, endocrinology, forensics, hematology, and anthropology. Dental age can also be considered as variable for diagnosing growth retardation in PEM children.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.