The prevalence of dental caries in European Children (0-18 years) and Associated Risk Factors
Introduction
Dental caries (also known as tooth decay or a cavity) is a disease where bacteria (in the presence of food) damage the hard tooth structure (Enamel, Dentin and Cementum).
Acs et al. (1992) showed that three year-olds with nursing caries (caries caused due to prolonged breast and bottle feeding) with atleast one pulpally involved tooth were likely to weigh about 1 kg less than the children without nursing caries. They also reported that, when dental rehabilitation was carried out, the children’s growth rate increased. Therefore, it appears that the poor oral conditions were compromising nutritional intake. Poor oral health can have a profound effect on general health and quality of life (Peterson et al., 2005).
The decline in the prevalence of dental caries in Western European countries was documented at the ‘Second International Conference of Declining Caries‘held in London in April 1994 (Naylor, 1994). In Central and Eastern Europe, the prevalence of caries is still high and there are no signs of substantial improvements. In the recent years an increasing number of papers have shown that the prevalence of dental caries was highest in the lowest socioeconomic strata with the immigrants of Europe (Bratthall et al., 2000) showing the skewed nature.
Dental caries is still a common disease among children and adolescents (Nithila et al., 1998; Marthaler, 2004) and affects 46% of 4-year-old children (Stecksen-Blicks et al., 2004) and 80% of 15-year-olds (Hugoson et al., 2005). Furthermore, there is a trend in many developed countries for the prevalence of dental caries to increase again, especially among young children (Haugejorden and Birkeland, 2002; Stecksen-Blicks et al., 2004), after a long period of caries decline (Marthaler, 2004). The purpose of this systematic literature review is to summarize the prevalence of dental caries in European children (0-18 years) since 1995 (end of decline) till March, 2011.
Methods
“A systematic literature review can be defined as the rigorous search, selection, appraisal, synthesis and summary of the findings of the primary research in order to answer a specific question” (Parahoo, 2006:134)
Review Questions
What is the available evidence regarding the prevalence of dental caries in European children (0-18 years) since 1995
What are the factors associated with such prevalence
Objectives
- To investigate the prevalence of dental caries among children up to the age of 18 years.
- To study the risk factors associated with the prevalence.
- To analyze the data odds ratio and confidence interval were reported. Odds ratio is the ratio of the odds of an event occurring in one group to the odds of it occurring in another group.
Source of Information
PubMed and Science Direct were extensively searched to retrieve articles. An additional supplementary search was also done. The initially identified papers were carefully examined which provided the further relevant articles. Other UEL-databases (Medline, EBSCO, Project Muse) were also searched. An additional advanced search was done on British Dental Journals.
Search Strategy
The key words included in the search strategies in PubMed and Science Direct were (dental caries, prevalence, Europe, children, risk factors) related to the research questions. One of the search strategy is described in detail below:
Search Strategy PubMed:
(“Epidemiology”[Subheading] OR “Epidemiology”[All Fields] OR “Prevalence”[MeSH Terms]) AND (“Dental Caries”[MeSH Terms]) AND (“Europe”[MeSH Terms] OR “Europe”[All Fields])=3484
(“Epidemiology”[Subheading] OR “Epidemiology”[All Fields] OR “Prevalence”[MeSH Terms]) AND (“Dental Caries”[MeSH Terms]) AND (“Europe”[MeSH Terms] OR “Europe”[All Fields]) AND (“Risk Factors”[MeSH Terms])=387
((“Epidemiology”[Subheading] OR “Epidemiology”[All Fields] OR “Prevalence”[MeSH Terms]) AND (“Dental Caries”[MeSH Terms]) AND (“Europe”[MeSH Terms] OR “Europe”[All Fields]) AND (“Risk Factors”[MeSH Terms]) AND (“Infant”[MeSH Terms] OR “Child”[MeSH Terms] OR “Adolescent”[MeSH Terms])=302
((“Epidemiology”[Subheading] OR “Epidemiology”[All Fields] OR “Prevalence”[MeSH Terms]) AND (“Dental Caries”[MeSH Terms]) AND (“Europe”[MeSH Terms] OR “Europe”[All Fields]) AND (“Risk Factors”[MeSH Terms]) AND (“Humans”[MeSH Terms]) AND English[lang] AND (“Infant”[MeSH Terms] OR “Child”[MeSH Terms] OR “Adolescent”[MeSH Terms]) AND (“1995?[PDAT] : “2011”[PDAT]))Limits: English, Humans=179
Total 179 articles were retrieved in this single search. The titles of 179 journals were read and inclusion- exclusion criteria were applied and 50 papers were selected.
Abstracts of 50 papers were critically read and finally six papers were included in the study. Four papers were identified and included from the reference lists, three papers were added by the manual searching of local journals (to include papers from all geographical regions of Europe) and one journal was retrieved from British Dental Journals.
Sixteen papers from different countries of Europe (England, Scotland, Wales, Northern Ireland, Norway, Kosovo, Germany, Lithuania, Spain, Latvia, Sweden, Portugal, Turkey and Greece) were included in this review.
Inclusion Criteria
Studies conducted in Europe.
Studies reporting overall prevalence of dental caries in dmft/DMFT (The number of D=decayed; M=missing due to caries; F=filled T=teeth in a case or individual, one of the most reliable dental caries index).
Studies that reported risk factors.
Original papers published in English.
Studies including children (0-18 years). This age group was chosen because this is the root foundation stage where good habits are developed and incorporated in the daily life. Preventive measures if used give the best outcomes.
Studies conducted from 1995. There was constant decline in dental caries in Central and Western Europe till 1995 but after this period, there was a tendency towards an increase in dental caries (Mathaler et al., 1996) – the reason to select the studies from 1995 till 2011.
Exclusion criteria
- Studies without the overall prevalence of dental caries.
- Papers not published in English.
- Studies not using the World Health Organisation DMFT criteria.
- Studies with single person opinion.
- Studies on age group > 18years.
- Studies involving cases with hospital and special dental care needs.
Quality Assessment System
Wong et al (2008) argued that quality assessing tools like QUOROM, CONSORT, STARD and STROBE were aimed at authors for reporting, not for reviewers and proposed QATSO guidelines for observational studies. As QATSO was used, the following parameters and scoring system were considered for this review, for methodological flaws (internal validity and generalisation (external validity). :
Sample size: ?1000=1, <1000=0.
Response Rate: ?60%=1, <60%=0.
Number of recruitment sites: ?5=1, <5=0.
Sampling strategies: Probabilistic=1, Non-probabilistic=0.
Statistical analysis: Yes=1, No=0.
Table 1
Each study was coded A to C (on the basis of above criterion) to measure its quality.
High Quality (A) — score ?4.
Fair quality (B) — score 2 to 3.
Poor Quality (C) – score < 2.
Results
The findings reported in the reviewed studies suggested the prevalence of dental caries ranged from 25% in Scotland (mean dmft1.1) to 86.31% in Kosovo (South Eastern Europe) (dmft-5.8). All the studies used WHO criteria to record the caries index (mean dmft/DMFT) indicating the prevalence of dental caries, this facilitates comparison between the studies of various regions.
Three studies (Studies 1, 9 and 16) show very high DMFT in Kosovo (mean DMFT=5.8) and Lativia (mean DMFT=5.0). Sweden, Turkey, Germany, Norway, Portugal, Lithuania and Greece were reported to have mean DMFT index ranging from 2.05 to 3.19 (Studies 3,4,10,12,13,14 and 15).
A low caries index (mean DMFT<2) was found in the UK (England, Wales, Scotland and Northern Ireland) (Studies 2,6,7,8 and 11). Comparing the studies 2 and 11, it was found that the mean DMFT index tends to increase with increasing age (Scotland 2007/08; mean dmft 3 year-olds =1.0, mean dmft five year-olds= 1.87).
Studies that reported risk factors mostly used logistic regression to quantify different independent variables (sugar consumption, preventive measures, socioeconomic factors and so on) with dental caries as the dependent variable. Most of the studies used the above mentioned variables. Eagle et al. (2003)
(study 3) reported the form in which sugars are consumed as an important predictor for dental caries; consuming sweetened tea and milk increased the risk of caries by 225 times and 15 times (reference water =1) (p<0.001) which is statistically significant. The risk of developing caries increased to 1.39, 1.44, 1.46 and 1.68 times when processed sugars were consumed once, twice, three times and four times respectively as opposed to never consuming processed sugars as reference (=1) (Gac Sanit; Study 5)
Socioeconomic factors (study 2,10,11,12,13,14 and 15) were also reported to be an important predictor for causing dental caries. Living in remote areas was reported to be a protective factor with cities as reference. The risk of having caries in remote and rural areas was reported to range between 0.29 times (CI 0.13-0.63; p=0.002) to 0.52 (CI 0.39-0.69) and this is statistically significant. People living in deprived areas (including immigrants) were reported to be more vulnerable. The odds of developing caries was 2.9 times (CI2.31-3.64; p<0.001) (study 2), 5.32 times (p<0.01) (Study 13) and 5.94 times (p<0.01) with native/caries free population as reference. The risk of developing caries was reported to be 1.68 times higher in children with mothers having secondary education as opposed to the children whose mother had done higher studies (Constantine et al. (2011); Study 15). Eagle et al. (2003) (study 3) reported that 70% of the mothers having caries free children knew about caries and its prevention but only 22.5% of mothers having children with caries were aware of this problem (p<0.001). The results were statistically significant.
With daily tooth brushing as reference, the risk of having dental caries for children who brushed on alternate days was 1.48 times (CI 1.22-111.78)higher; for children who brushed with two days gap was 1.57 times(CI 0.91-2.33) higher and for those who brushed with gap of three or more days was 1.60 times(CI 1.20-2.28) higher (Study 5). Applying excessive toothpaste while brushing was reported as a risk factor for caries. Risk of caries was 1.32 times (CI 1.10-2.16) and 1.52 times (CI1.20-1.61) higher if the amount of tooth paste used was 2/3 of the tooth brush head size and whole head size respectively with 1/3 of the toothbrush head size as reference(=1) (Study 5). Constantine et al. (2011) reported sealants (material used by dentists to fill the deep pits and fissures (where caries start), of teeth in young children) as a protective factor the risk of having caries in children with sealants was 0.76 times the children without sealant use (OR=0.76; CI=0.57-1.00; p<0.05) which was statistically significant (Study 15).
Discussion
Based on sixteen papers, this review demonstrates variation in the prevalence of dental caries in different regions of Europe and it ranged from 1.0 (Scotland) to 5.8 (Kosovo) (dmft). Although, the prevalence of dental caries has decreased in Western and Central Europe, Eastern Europe is still facing a high prevalence of dental caries. This is similar to the findings of Marthaler, 2004. In this review lower socio-economic status, sweets consumption and inadequate oral hygiene were reported as major risk factors. Studies 3 and 5 reported sugar consumption as a cause of dental caries. Similar association was reported by Cottrell, 2005. Awareness of mothers and rurality were reported as a protective factor for dental caries in studies 10,11,12 and 13. These findings were similar to Marserijian, Tavres, Hayes, Soncini and Trachtenberg (2008), who showed that caries were higher in urban children of New England than rural children. Tooth brushing was also reported as protective factor in study 5.
Limitations of the study included, limited exploration of other factors that could be significant due to limited number of papers (+15). Journals could not be retrieved from all the European countries hence the result was generalised more widely. In most of the studies dental mirrors, dental probes, cotton rolls and natural daylight were used and these conditions were sub-optimal. Radiographs, artificial light and compressed air were not available. Finally, no attempt was done to perform a meta-analysis in the review to give a pooled prevalence.
Despite, above mentioned limitations, this review can serve as a starting point for more ambitious reviews. All the studies included in this review used WHO criteria for recording the prevalence of dental caries (DMFT). The higher prevalence of dental caries in Eastern Europe is attributed to their under developed health system. Hence, there is need to strengthen the health systems in Eastern European countries. Highest caries prevalence is in lowest economic strata (Bratthall et al., 2000). Hence, there is immediate need to target lower socio-economic strata in the public health policies.
References
- Miller J, Vaughan-Williams S E, Furlong R, Harrison L. Dental caries and children’s weights. J Epidemiol Community Health 1982; 36: 49–52. | PubMed | ISI | ChemPort |
- Acs G, Lodolini G, Kaminski S, Cisneros G J. Effect of nursing caries on body weight in a pediatric population. Pediatr Dent 1992; 14: 302–305. | PubMed | ChemPort |
- Acs G, Shulmann R, Ng M W, Chussid S. The effect of dental rehabilitation on the body weight of children with early childhood caries. Pediatr Dent 1999;21: 109–113. | PubMed | ChemPort |
