Dental caries prevalence among 12-14 year-old

schoolchildren in Riyadh: A 14 year follow-up study

of the Oral Health Survey of Saudi Arabia Phase I

The objective of this study was to assess the changes in dental caries status among 12-14 year-old schoolchildren in Riyadh, Saudi Arabia, fourteen years after the conduct of an Oral Health Survey of Saudi Arabia Phase I. A total of 205 students of the first grade of intermediate schools (12-14 years of age) were randomly selected, using stratified random sampling from 16 schools in Riyadh, Saudi Arabia. The children were examined, by two trained examiners, for dental caries using the World Health Organization criteria.  Of the total sample, only 6.3% were caries free showing that the caries prevalence was 93.7%. The mean DMFT value for the total sample was 5.94 (± 3.95). Male students had a significantly higher mean DMFT value (7.20 ± 3.89) than the female students (4.66 ± 3.59) (P<0.0001). Students residing in urban areas demonstrated a significantly higher mean DMFT value (6.45 ± 3.92) compared to students of rural areas (4.61 ± 3.72) (P=0.003). No statistically significant differences were found between the mean DMFT values of Saudi and non-Saudi students (6.09 and 5.35, respectively) (P=0.273) and also no statistically significant differences were found between the mean DMFT values of private and public school children (P=0.439). The caries prevalence has increased considerably among intermediate schoolchildren in Riyadh, 14 years after the conduction of the Oral Health Survey of Saudi Arabia Phase I.

Dental caries is a disease, which afflicts humans of all ages and in all areas of the world. It is a disease that might never be eliminated because of its multifactorial nature including social, cultural, behavioral, dietary and biological factors that can be associated with its initiation and progression. Several studies have been carried out to assess the dental caries prevalence among children in different parts of the world.^1-6 In Saudi Arabia, several reports have been published on the prevalence and severity. of dental caries among school children in Riyadh,^7-10 and in other parts of the kingdom.^10-17

In 1987, a comprehensive epidemiological survey of oral diseases, beliefs, attitudes and habits of the people living in Riyadh region in Saudi Arabia was conducted and was published in 1991.¹⁸ This study, known as the Oral Health Survey Phase I (OHSI), presented very important baseline data on the dental heath status of the population in the central province of Saudi Arabia. The results of this study showed that 41.8% of the 12-year-old age group was free of dental caries in their permanent teeth and that the mean DMFT value was 1.61 for males and 1.68 for females.¹⁸

Of the two hundred and five students examined, 103 were males and 102 were females. About 80% of the study sample were Saudis and nearly 72% were selected from urban areas.

Of the total sample, only 6.3% were caries free indicating that the caries prevalence was 93.7%. The mean DMFT value for the whole sample was 5.94 (± 3.95). Analysis of the DMFT showed that the mean D value was 5.44 (± 3.87), the mean M value was 0.15 (± 0.62) and the mean F value was 0.35 (± 0.97) indicating that the D (decay) component was the major constituent of the DMFT index (Table 1).

 Male students had a higher mean DMFT value (7.20 ± 3.89) than the female students (4.66 ± 3.59) and the difference between the two groups was statistically significant (P < 0.0001) as shown in Table 1. The mean value of decay component of the DMFT was the highest for both males and females (6.71 and 4.16, respectively) and the difference between the two groups was found to be statistically significant (P < 0.0001) as shown in Table 1.

Students residing in urban areas demonstrated a significantly higher mean DMFT value (6.45 ± 3.92) compared to students from rural areas (4.61 ± 3.72 and P = 0.003) as shown in Table 2. For both groups the D component constituted over 91% of the total DMFT value.

Table 3 shows that no statistically significant differences were found between the mean DMFT values of Saudi and non-Saudi students at 6.09 and 5.35, respectively. Differences were found, however, between the mean values of the M and F components of the index between Saudi and non-Saudi students at P = 0.037 and P = 0.002, respectively (Table 3).

Private school children were found to have a higher mean DMFT value than public school children but the difference between the two groups was not statistically significant (P=0.439) as shown in Table 4. By comparing the mean DMFT values among the public schools of the urban area, the Western area of Riyadh had the highest value of 7.19 (± 4.33) while the lowest value was in the Central area 5.73 (± 3.94), but the difference between the two groups was not statistically significant (Table 5).

This study was a follow-up of the national survey (OHSI), carried out in Riyadh in 1987.¹⁸ It was conducted to identify any changes that might have occurred in the caries status during the 14 year time difference among intermediate school children. In the OHSI, Al-Shammary et al. found that among the 12-years-old group, 41.8% were free from caries, whereas the results of this study showed that only 6.3% of the total sample was caries free. The present study shows that the caries prevalence has increased to a very serious level compared to the previous studies.^7,8,10,18

The results of OHSI showed also that the mean DMFT value for 12-year-old students was 1.61 for males and 1.68 for females.¹⁸ In this study however, the mean DMFT value was 7.20 for males and 4.66 for females, which shows an increase of nearly four and a half times for males and over two and a half times for females. The mean DMFT value in this study was also found to be higher than the values noticed in other studies done on similar age groups in different parts of Saudi Arabia,^7,8,12-14 and in other countries.^{2, 3,6} This increase in caries levels might be attributed to changes in the life style and eating habits such as the greater intake of in between meal snacks and the increase in the frequency of consumption of sweetened foods and drink.^8,14,20-22 It could also be compounded by a general lack of interest in dental health care and preventive measures, low dental health knowledge and difficulties in obtaining professional dental care.

Male students in this study had a higher mean DMFT value than females, which is the opposite of the results obtained in the OHSI where females had higher mean DMFT value than male students. This finding could be related to the fact that female students in intermediate schools were found to use the toothbrush, toothpaste and clean their teeth more frequently than their male counterparts.²³

The decay component was the major contributor in the DMFT value, in this study, constituting over 91% of the score. This is consistent with the results of the OHSI and other studies conducted on similar age groups in different areas of Saudi Arabia.^{7-9, 12-14} This is interpreted to mean that the high number of untreated caries is still prevalent and there is an immediate need for providing restorative services to this age group.

In this study, the mean DMFT value and the value of the D component were higher among students residing in urban areas compared to rural areas which does not agree with the findings of the OHSI where no difference between the two groups was found. A possible explanation might be that students residing in urban areas have more access to and consume more sweetened snacks and drinks than student residing in rural areas. 

No statistically significant differences were found between Saudi and non Saudi school children in the mean DMFT values and in the mean value of the decay component indicating that there were no differences in the eating habits and ways of living. Statistically significant differences, however, were found between the filled and missing component, which shows that non-Saudi children received less dental treatment possibly because they had limited access to dental health care.

Although the results of this study showed that private school children showed a higher mean DMFT value than public school children, this difference was not statistically significant. This finding disagrees with the findings reported by other studies where public school children presented with higher mean DMFT values.^{12, 24} It could be that students from private school were from higher socio-economic level, which might have given them a higher opportunity to gain access to more sugary snacks and drinks. Although, the differences found in mean DMFT values between western and central areas of Riyadh were not statistically significant, it could be attributed to differences in socio-economical levels.

The results of the present study showed that the dental caries prevalence has increased to a very serious level among intermediate school children in Riyadh in the last 14 years period since the OHSI was conducted. This indicates that there are still shortcomings in the area of both preventive and curative dental care.

The results of this study indicated that the prevalence of dental caries has increased considerably among intermediate schoolchildren in Riyadh, 14 years after the conduct of the Oral Health Survey of Saudi Arabia Phase I.

The author wishes to express her appreciation to Dr. Khalid Al-Wazzan and Dr. Nazeer Khan for their cooperation and data collection. The author is also grateful to Prof. E.S. Akpata, former faculty member of College of Dentistry, King Saud University, for assisting in the examiners' calibration

 
Table 3. Caries experience of intermediate schoolchildren in Riyadh by nationality (Saudi / non-Saudi)

Table 4. Caries experience of intermediate schoolchildren in Riyadh by school type (public / private)