Dental caries is one of the worlds commonest diseases and affects between 60-90% of schoolchildren. The onset and progression of caries varies across and between populations due to behavioural and sociodemographic factors. Some studies have suggested fixed patterns of caries progression and suggested that these are universal. If this is the case the future increment of caries for particular populations could be predicted which would assist service planning.
The main aim of this review was to quantify caries progression rates in the primary and permanent dentition of Western or comparable populations
Methods
Searches were conducted in the Medline/PubMed, Embase, CINHAL and Cochrane Library for studies reporting caries progression data. Prospective, retrospective, cohort, and intervention studies published in English, Dutch, or German were considered. Studies need to report data from at least 2 full mouth examinations for dental caries (reported as dmfs/DMFS, dmft/DMFT or caries-free) with a first examination after 1974 and a second examination before the age of 22years.
Two reviewers independently screened and selected the studies and assessed risk of bias using a specially developed form including 7 items. One reviewer extracted the data which was checked by a second reviewer. Higher caries progression rates we expected in populations with higher baseline caries in permanent dentition. Change in caries-free patients and increment in DMFS/DMFT was based on the first and last measurements only. Meta-analysis and meta-regression analysis were conducted.
Results
- 43 studies involving 56,376 patients were included.
- 32 studies (39,429 patients) were on permanent teeth.
- Primary dentition
- Annual decline in percentage of caries-free children ranged from 3.8% to 12.2%
- Annual increments ranged from −1.0 to 1.0 in dmfs and from −0.3 to 0.3 in dmft
- Permanent dentition
- Annual decline in percentage of caries-free patients ranged from 0.8% to 10.2%
- Annual increments ranged from 0.07 to 1.77 in DMFS and from 0.06 to 0.73 in DMFT
- 15 studies were included in the meta-analysis and meta-regression analysis
- The caries incidence rate was 0.11 (95%CI; 0.09 – 0.13).
- DMFS and DMFT increments are shown in the table.
| DMFS Increment (95%CI) | DMFT Increment (95%CI) | |
| No. of studies | 22 | 13 |
| No. of patients | 11,300 | 24,753 |
| Unadjusted | 0.43 (0.04 to 0.83) | 0.18 (–0.04 to 0.40) |
| Adjusted for bitewing & age at baseline | 0.64 (0.31 to 0.96) | 0.18 (0.02 to 0.35) |
| Adjusted for caries experience at baseline | 0.37 (0.04 to 0.70) | 0.23 (0.06 to 0.40) |
| Adjusted for decade + preventive intervention | 0.36 (–0.02 to 0.73) | 0.07 (–0.24 to 0.39) |
| Adjusted for relevance of evidence + risk of bias | 0.46 (0.08 to 0.83) | –0.04 (–0.34 to 0.26) |
Conclusions
The authors concluded: –
Pooled caries progression rates were not achievable for the primary dentition due to the limited number of included studies and the non-standardised approaches of exfoliated teeth. For the permanent dentition, our pooled findings on caries progression in populations were a caries incidence rate of 0.11 (0.09–0.13) per person- year at risk, an increment in DMFS of 0.43 per year of follow- up, and an increment in DMFT of 0.18 per year of follow-up. So far, the caries incidence rate measure rarely has been used in longitudinal oral health research but seemed fairly stable and therefore most promising. When using our progression rates for the prediction of caries increments, caution is justified because these measures were influenced by methods of the studies included. For better insight into caries progression rates in populations and usefulness for policy makers, more standardisation of measuring and study methods in (epidemiological) research is essential.
Comments
A broad search strategy was used and included studies were restricted to those published in English, Dutch or German which may be appropriate for the targeted group of Western Population , although it is possible that some relevant studies may have been excluded. In addition, a non-validated tool was used to assess the relevance and quality of the included studies. So, while this review provides some interesting information the authors themselves raise a number of issues that need to be taken into consideration. There were wide variations in the methodologies of the included studies. In particular in relation to the assessment of caries with some studies using radiographs and drying of teeth, although these should be consistent within studies. The filled component of the DMF index is probably influenced by the threshold at which a dentist will intervene, and this is likely to vary between decades and between countries.
Links
Primary Paper
Hummel R, Akveld NAE, Bruers JJM, van der Sanden WJM, Su N, van der Heijden GJMG. Caries Progression Rates Revisited: A Systematic Review. J Dent Res. 2019 Jul;98(7):746-754. doi: 10.1177/0022034519847953. Epub 2019 May 9. PubMed PMID:31070943; PubMed Central PMCID: PMC6591514.
