Dental caries in children is common in low- middle- and high-income countries with between 60-90% of children in industrialised countries being affected, and yet, it is almost entirely preventable. Oral health education promoting behaviours and conditions that reduce risk and improve oral health are important.  The 1996 review of dental health education by Kay and Locker demonstrated a short-term effect on plaque but no effect on caries and the findings of the 2013 Cochrane review by Cooper et al (Dental Elf – 3^rd Jun 2013) were similar.

The aim of this review was to evaluate the effectiveness of oral health educational actions in the school context on improving oral hygiene and dental caries in schoolchildren.

Methods

Searches were conducted in the Medline, Cochrane CENTRAL, Embase, LILACS databases from /01/ 1995 until 09/06/2015 with no language restrictions. Randomised controlled trials involving children aged 5-18 years of age in a school setting were considered.

Two reviewers independently selected studies risk of bias was assessed in five specific domains: selection of participants; allocation sequence concealment; blinding of participants and evaluators; incomplete outcome data; and selective outcome reporting.  The primary outcomes were dental caries; plaque accumulation; gingivitis. A meta-analysis was carried out using fixed-effects models.

Results

• 12 trials were included, 6 randomised by school, 2 by class at 4 at individual level.
• In total 3932 children (1864 test/ 2068 control) aged 6 -15 participated.
• None of the studies was considered to be at low risk of bias.
• There was considerable methodological variation between the studies which were characterised into 4 groups, Oral Health Education (OHE), Oral Health Instruction (OHI), Tooth brushing demonstration (TD), Supervised Tooth brushing (ST).
• 5 studies showed a reduction in plaque levels,
• 2 studies with gingivitis as the outcome found no effect.
• There was not enough evidence on the effectiveness of the interventions in reducing dental caries.

Conclusions

The authors concluded: –

traditional oral health education was effective in reducing plaque accumulation over a short period. This reduction was of small magnitude. OHE was not effective for gingivitis while for caries the findings were conflicting. There is no long-term evidence on the effectiveness of these interventions in preventing plaque accumulation, gingivitis and dental caries in schoolchildren. This may be due to the variability of OHE methods deployed in the individual studies.

Comments

This review follows a standard methodology and covers similar ground to the 2013 Cochrane review. This new review included 12 studies only 2 of which were published after the Cochrane review.  Of the studies included in this review only 2 were included in this new review both of which were scored lower in terms of risk of bias than by the Cochrane reviewers. Also 3 studies included in this review were excluded by the Cochrane team.  Despite the inclusion and exclusion decisions the overall finding of this review in in line with the Cochrane and other reviews. There is limited evidence to show that short term reduction in plaque levels and improvement in knowledge can be achieved but little or no evidence in relation to caries.  The latter is perhaps no surprising as in most cases the duration of trials is not long enough for changes in caries status.  As the Cochrane review noted,

there is a need for further high quality research to utilise theory in the design and evaluation of interventions for changing oral health related behaviours in children and their parents.

Links

Primary paper

Stein C, Santos NML, Hilgert JB, Hugo FN. Effectiveness of oral health education on oral hygiene and dental caries in schoolchildren: Systematic review and meta-analysis. Community Dent Oral Epidemiol. 2017 Aug 16. doi:10.1111/cdoe.12325. [Epub ahead of print] PubMed PMID: 28815661.

Other references

Dental Elf – 3^rd Jun 2013

Insufficient evidence for the efficacy of primary school-based behavioural interventions for reducing caries

Kay E, Locker D. Is dental health education effective? A systematic review of current evidence. Community Dent Oral Epidemiol. 1996;24:231-235.