Commentary

With dental extractions being the most common reason for a child between five and nine years of age in England to have a general anaesthetic, the need for effective methods of improving oral health in children cannot be underestimated.1 Oral health education in a school setting may be an effective part of the preventive armamentarium to improve schoolchildren's oral health; the aim of this systematic review was to determine if such interventions might improve oral health in terms of reduced plaque levels, gingivitis and dental caries.

The literature search for this review was limited to 1995-2015 with the rationale for this having been the most recent similar systematic review was completed in 1994;2 the search for this earlier review combed the Medline database between 1982-1994 using only the subject headings ‘dental health education, oral health promotion and effectiveness’. In addition, a scoring system was used in this earlier review and papers excluded below a certain score. As such there is potential risk that other suitable publications were not identified for inclusion in the current review.

Studies were included ‘without time restriction’ and as such there was no minimum follow-up period for included studies. As a result there was a varied follow-up period in the included studies, eg one month to four years. The authors highlight the need for longer-term studies to be carried out, particularly to identify any changes in dental caries.

The authors make note that ‘significant methodological variability was found among the interventions performed in the included studies’. Of note, the inclusion of studies ‘disregarded the dental caries level at the study's beginning, exposure to fluoride and current dental treatment’. This clinical heterogeneity (which also included variable sample population demographics, follow-up times and interventions), may have warranted a descriptive analysis rather than meta-analysis of the data. Although statistical homogeneity was observed, it was largely due to the low number of studies and small sample size. Indeed, a number of oral health promotion reviews have noted similar heterogeneity between included studies with no meta-analyses having been carried out as a result.3, 4, 5

Risk of bias assessment was completed for all included studies; the authors made no comment on the impact that the risk of bias may have had on the results with the risk of bias table highlighting that none of the included studies was at overall low risk of bias.

Though not specifically part of this review, the authors make no mention regarding the need for future studies to include appropriate and validated child-centred outcome measures, though they do note the need to determine the cost effectiveness of oral health education interventions.

Although the authors reach the distinct conclusion that traditional oral health educational actions were effective in reducing plaque in the short-term, but not gingivitis, perhaps there should be more caution in their interpretation of the results given the clinical heterogeneity and risk of bias of the studies included. Overall, there remains a need for further well designed randomised controlled studies with longer follow-up periods to determine the most effective methods of school-setting oral health education for improved oral health in children.