Dentition status in relation to nutritional condition among a group of intermediate school students in Al-Najaf city / Iraq

Background: Nutrition can affect the development and integrity of the oral cavity as well as the progression of oral diseases such as dental caries which was the most predominant and wide spread not life threatening human diseases especially in developing countries as in Iraq. This study was conducted to assess the occurrence, prevalence and severity of dental caries condition and their relations to nutritional status among intermediate schools females in Al-Najaf city in Iraq. Materials and methods: This study was conducted among intermediate schools females aged 13, 14 and15 years old and the total sample consisted of 754 students. The assessment of nutritional status was performed using body mass index (BMI) following Centers for Disease Control and Prevention growth chart (2000). Diagnosis and recording of dental caries was according to the criteria of WHO 1987. Results: The percentage of well-nutrition was (96.2%) while the prevalence of malnutrition was (3.8%). Result showed that only 5.17% of the total sample was caries-free. The mean dmft for deciduous teeth was equal to (1.77±0.15) and dmfs (3.92±0.39), while concerning permanent teeth the mean DMFT was equal to (4.68±0.10) and DMFS (6.22±0.16), significant differences were seen between DMFT, DMFS and age while opposite was found with nutritional status, and no significant differences were seen between caries experience of primary teeth and age and this similar was found with nutritional status Conclusion: This study revealed that a higher prevalence of dental caries among well-nourished females students aged 13-15 years. Therefore, there is need for an improving public and school preventive programs, and encouraged to orient health knowledge in a positive direction.


INTRODUCTION
Adolescents are tomorrow's adult population, adolescence may represent a window of opportunity in which to prepare nutritionally for a healthy adult life (1) .This crucial period of transition is identified by a range of age of 10-19 years by the World Health Organization.Early adolescence after the first year of life is the critical period of rapid physical growth and changes in body composition, physiology and endocrine (2) .Adolescent girls health covers nutritional status, morbidity, and reproductive health.During the period of adolescence the nutrient needs are the greatest (3) .
Nutrition is considered as one of the most important factors influencing the quality of human life worldwide, also nutritional deficiency is directly related to the retardation of growth and development, decrease resistance to infection and environmental hazards (4) .Adequate nutrition and healthy eating and physical exercise habits at this age are foundations for good health in adulthood (5)   .Nutrition is an integral component of oral health.There is a continuous synergy between nutrition and the integrity of the oral cavity in health and disease (6) .Diet and nutrition affects the integrity and developing of the oral cavity in addition to the evolution of oral diseases (7) .The World Health Organization defines malnutrition as a number of condition with specific etiology derived from the cellular imbalance between supply of one or more nutrients, energy and the body's demand for them to ensure growth, maintenance, reproduction and specific functions (8,9) .
Dental caries is a demineralization of the inorganic part of the tooth with the dissolution of the organic substance depending on interaction of several factors: oral micro flora (acidogenic bacteria) diet (fermentable carbohydrate), time and host (10,11) .
Iraqi studies showed a high prevalence and severity of dental caries (12,13,14) .According to age, in this study caries experience was discovered to be increase with age, with highly significant difference, this finding is in agreement with previous Iraqi studies among different age groups (12,15) this may be related to accumulative and irreversible nature of dental caries (16) .There was no significant differences between DMFT, DMFS and its components with nutritional status This finding was similar to studies (17,18) .

MATERIALS AND METHODS
This survey was conducted among urban intermediate school females students aged 13-15 years old in AL-Najaf city governorate in Iraq.The study was conducted during the period between the beginnings of January 2016 till the end of March 2016.
According to the General Directorate of Education reports (2015), there was (12347) females students aged 13-15 years old distributed among (25) intermediate schools in Al-Najaf city, they are consisted of (4569), ( 3890) and (3888) for age 13, 14 and 15 years old respectively.The sample representative 16 an intermediate females school were distributed in AL-Najaf city which were randomly selected from 25 intermediate females school in different areas of the city, adolescents who are healthy and without any systemic disease were examined.The age was taken according to the criteria of World Health Organization (19) and according to the last birth day, and the cross sectional random sample was calculated for prevalence studies by the formula as n=ZP 2 (1-P)/d 2 (20) .
Body Mass Index (BMI): This index is a number calculated from the child's weight and height, according to this formula (21) : Body weight / (height) 2 =BMI Kg/m 2 According to specific chart (22) .The values of nutritional indicators were compared with international reference values using CDC growth charts (Center for Disease and Control and Prevention, 2000).
Diagnosis and recording of dental caries was assessed according to the criteria described by WHO (23) .For primary and permanent dentition, if primary and permanent teeth occupied the same tooth space, the status of permanent tooth only was considered (19) .Data description, analysis and presentation were performed using computer software program (SPSS version 18).

RESULTS
In the present study, the total sample consisted of (754) female students, they were 223, 267 and 264 students for 13, 14 and 15 years age group respectively.
Table (1) illustrates the distribution of the total sample by age groups.The table shows 14 years age group exhibited the high number among the total sample followed by 15 years age group, while 13 years age group the lowest.
Table (2) illustrates the distribution of students according to nutritional status by age groups.This study revealed that for the total sample the percentage of total of well-nourished girls was higher than malnourished students among three age groups.Regarding malnourished the table shows that 13 year age students exhibited the low percentage compared with other two age groups.
Table (3) shows the distribution of caries free among students in regarding to the age groups.High percentage of caries free was recorded among 14 years age group, followed by age 15 years till reach the lowest at the age 13 years.
Table (4) shows the distribution of caries free among students in regarding to the nutritional status.Regarding malnourished students very low percentage was recorded of caries free compared with the well-nourished students.
Table (5) demonstrates the mean values and standard errors of caries experience by fractions in primary dentition, concerning three age groups students.Caries experience was found to be higher in the 13 years age students followed by students with 14 years age while the lowest among the 15 years age group.Differences was statistically no significant excited between age groups (p>0.05).Decayed surface was found to be the largest fraction of dmfs value compared to ms and fs among all age groups.
Table (6) illustrates the mean values and standard errors of caries experience by fractions in primary dentition among students in regarding to nutritional status.Caries experience was found to be higher in the well-nourished students than malnourished group.Statistically no significant differences were recorded among both groups (P>0.05).Decayed surface was found to be the largest fraction of dmfs value compared to the ms and fs among both groups.
Table (7) demonstrates the mean values and standard errors of caries experience by fractions in permanent dentition, concerning three age groups students.Caries experience was found to be higher in the 15 years age students followed by students with 14 years age while the lowest among the 13 years age group.Differences was statistically highly significant excited between age groups (p= 0.000).Decayed surface was found to be the largest fraction of DMFS value compared to MS and FS among all age groups.
Table (8) illustrates the mean values and standard errors of caries experience by fractions in permanent dentition among students in regarding to nutritional status.Caries experience was found to be higher in malnourished than well-nourished groups students.Statistically no significant differences were recorded among both groups (P>0.05).Decayed surface was found to be the largest fraction of DMFS value compared to the MS and FS among both groups.

( 1 )
Master Student.Department of Pedodontics and Preventive Dentistry, College of Dentistry, University of Baghdad.(2) Assistant Professor, Department of Pedodontics and Preventive Dentistry, College of Dentistry, University of Baghdad.