Abstract: We included four studies involving 2302 children. One study was at unclear risk of bias and three were at high risk of bias. Included studies reported heterogeneity in both the intervention design and outcome measures used; this made statistical comparison difficult. Additionally this review is limited by poor reporting of intervention procedure and design. Several BCTs were identified in the trials: these included information around the consequences of twice daily brushing and controlling sugar snacking; information on consequences of adverse behaviour and instruction and demonstration regarding skill development of relevant oral health behaviours. Only one included study reported the primary outcome of development of caries. This small study at unclear risk of bias showed a prevented fraction of 0.65 (95% confidence interval (CI) 0.12 to 1.18) in the intervention group. However, as this is based on a single study, this finding should be interpreted with caution. Although no meta-analysis was performed with respect to plaque outcomes (due to differences in plaque reporting between studies), the three studies which reported plaque outcomes all found a statistically significant reduction in plaque in the intervention groups with respect to plaque outcomes. Two of these trials involved an 'active' home component where parents were given tasks relating to the school oral health programme (games and homework) to complete with their children. Secondary outcome measures from one study reported that the intervention had a positive impact upon children's oral health knowledge. Currently, there is insufficient evidence for the efficacy of primary school-based behavioural interventions for reducing caries. There is limited evidence for the effectiveness of these interventions on plaque outcomes and on children's oral health knowledge acquisition. None of the included interventions were reported as being based on or derived from behavioural theory. 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.

Plain-language summary: This review examined how successful the interventions in the suitable studies were in improving dental health in children aged from 4 to 12 years. The latest search of relevant studies was carried out on 18th October 2012. Interventions were programmes that enabled children to. ∙ Making lasting changes to toothbrushing habits.  ∙ Reduce the amount and how often food and drink known to cause tooth decay were consumed. The trials had to include an educational element which taught skills or gave instructions and one or more accepted techniques to change behaviour. Out of 1518 possible studies found only four were sufficiently relevant and of high enough quality to be included in this review. One small study showed that children who received the behavioural intervention developed fewer caries during the study. Three studies showed that there was less dental plaque (better oral hygiene) in the children in the behavioural intervention groups. More research is needed to confirm these findings. The dental health of 4 to 12 year olds is an important issue - reducing the amount of decay in this group would have a positive impact on overall health, particularly for those living in the poorest communities. More high quality research with well designed programmes will help to establish which techniques are most effective at changing child and parent behaviour to encourage good toothbrushing and discourage sugar snacking.