This study analyzed data regarding dental treatment needs and demographic variables of 13,398 young Israeli adults. Its predominant advantage is the large sample size which is optimally representative of Israeli young healthy adults. To the best of our knowledge, this is the first time this new database of computerized dental treatment records, which includes full and complete dental needs data, is being studied and published. Most of the soldiers in this sample were males (9:1 ratio), due to few females recruited to combat positions. We consistently demonstrated a reverse correlation between the level of SEC and ICS and higher dental treatment needs in all three treatment categories. The associations between socio economic status and dental needs have been established and described in previous studies [15,16,17], however, comprehensive studies regarding the correlation between dental caries and intellectual capabilities are few. Navit et al. tested 252 10–15 year old children for the correlation between IQ (according to Malin’s intelligence scale) and dental caries (DMFT index). No significant association between level of intelligence and caries prevalence was observed [18]. The current study offers a unique opportunity to explore a comprehensive database that enables a crossing of dental records with intellectual data. Our results found a statistically significant association between low intellectual capabilities and higher dental treatment needs. As there are almost no previous data regarding association between intelligence levels and caries prevalence, we may suggest that ICS serves here as an indirect marker of other, uncollected variables such as social or material deprivation, or educational level of the examinees’ parents. All these markers were already shown to be associated with caries prevalence [3,4,5,6,7, 19]; many studies suggest that children’s intelligence level is associated with parental education level (via genetic as well as environmental pathways) [20,21,22], and also with poverty [22,23,24]. However, the statistical significance we have shown could also be merely the result of the large sample size of our study (n = 13,398) rather than a difference so great that ICS could be useful for planning or evaluating interventions. Therefore, further studies should be performed, to study the association between ICS and caries prevalence, which is better measured directly by the DMFT (Decayed, Missing, and Filled Teeth) index, rather than by a proxy measure such as treatment needs.
Higher treatment needs were found among subjects whose parents came from Ethiopia or former USSR, indicating a clear need for preventive intervention among these two subgroups. These findings are similar to previous studies from Israel [10, 25,26,27,28]. Since both these populations were underrepresented in this study (for Ethiopian descendants: 1.7% among sampled subjects vs. 2.2% of the general Jewish population in 2013; for USSR origin: 12% vs. 15%) [11], this problem may be even more relevant in the general Israeli population. However, we could see that second generation subjects whose parents came from former USSR, had better oral health compared to subjects who immigrated themselves, suggesting a positive trend of improved health status among this subgroup, and possibly a marker of integration and assimilation.
The study has some limitations: we collected data regarding extractions but had no ability to ascertain whether the teeth were missing due to caries. If this had been available, it could have contributed to establishing a more thorough understanding of caries morbidity. Regarding the need for dental restorations, we could not exclude the need for restorations due to trauma or faulty restorations although we presume, judging by our experience that these are a minority that did not alter our results significantly.
We did not have access to data regarding oral hygiene, diet, smoking and other variables, which could shed light on causes for caries, and might further explain the relevance of ICS to untreated dental disease. Furthermore, all data collected were based on clinical and radiographic examination conducted by many military dentists with possible diversity in diagnosis of pathologies and their decisions regarding treatment needs. Examiners had received uniform training, but optimal calibration was not conducted. These examinations are mandatory but cases of refusal or missed examinations are possible and might have been undocumented.
At the present moment, dental health coverage in Israel is from birth to age 16 years. The intention is to eventually reach 18 years of age. Army recruits, therefore provide an optimal (albeit not maximal) age cohort for exploring wider dental health coverage. Results of the present study provide several indications for “at risk” criteria. These would include immigrants originating from Ethiopia and former USSR, lower SEC and low ICS groups.
The present study population has been utilized as representative for young adults in previous epidemiologic studies [24, 23, 10, 9]. Our results may therefore be considered as a baseline for future intervention programs. Dental caries is a chronic and progressive disease. Based on the recognition that Israeli military service is compulsory, and most immigrant soldiers live in Israel several years before induction, opportunities to prevent and control dental caries earlier in life exist and might lead to better oral health among recruits. Results of the present study indicate that interventions developed for the subgroups demonstrating higher needs, can serve as an important baseline against which to ascertain planning and optimal progress in the future.
The dental department of the IDF had focused in recent years on the enhanced treatment of two major populations- (1) Combat troopers; and (2) Low SES soldiers. For example, dental crowns and implants are provided to these soldiers while other mandatory service soldiers do not enjoy these benefits. Our study supports this rational by presenting evidence for the greater treatment needs in the Low SES population. This population also consists of (as expected) a high percentage of ‘lone soldiers’ (soldiers who immigrated without their parents) or immigrants with parents in Israel.
Furthermore, in the past, the dental department organized several intervention plans aimed at providing dental care for certain immigrant populations. We believe our results might support similar and enhanced plans in the future.