ObjectiveTo evaluate the effectiveness of the WhiteTeeth mobile app, a theory‐based mobile health (mHealth) program for promoting oral hygiene in adolescent orthodontic patients.MethodsIn this parallel randomized controlled trial, the data of 132 adolescents were collected during three orthodontic check‐ups: at baseline (T0), at 6‐week follow‐up (T1) and at 12‐week follow‐up (T2). The intervention group was given access to the WhiteTeeth app in addition to usual care (n = 67). The control group received usual care only (n = 65). The oral hygiene outcomes were the presence and the amount of dental plaque (Al‐Anezi and Harradine plaque index), and the total number of sites with gingival bleeding (Bleeding on Marginal Probing Index). Oral health behaviour and its psychosocial factors were measured through a digital questionnaire. We performed linear mixed‐model analyses to determine the intervention effects.ResultsAt 6‐week follow‐up, the intervention led to a significant decrease in gingival bleeding (B = −3.74; 95% CI −6.84 to −0.65) and an increase in the use of fluoride mouth rinse (B = 1.93; 95% CI 0.36 to 3.50). At 12‐week follow‐up, dental plaque accumulation (B = −11.32; 95% CI −20.57 to −2.07) and the number of sites covered with plaque (B = −6.77; 95% CI −11.67 to −1.87) had been reduced significantly more in the intervention group than in the control group.ConclusionsThe results show that adolescents with fixed orthodontic appliances can be helped to improve their oral hygiene when usual care is combined with a mobile app that provides oral health education and automatic coaching. Netherlands Trial Registry Identifier: NTR6206: 20 February 2017.

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.Abstract -Objectives: This systematic and meta-analytic review aimed to quantify the association of psychosocial correlates with oral hygiene behaviour among 9-to 19-year olds. Methods: A systematic search up to August 2015 was carried out using the following databases: PubMed, PsycInfo, Embase, CINAHL and Web of Science. If necessary, authors of studies were contacted to obtain unpublished statistical information. A study was eligible for inclusion when it evaluated the association between the psychosocial correlates and oral hygiene behaviour varying from self-reports to clinical measurements, including plaque and bleeding scores. A modified New Castle Ottawa Scale was applied to examine the quality of the included studies. Results: Twentyseven data sets (k) presented in 22 publications, addressing nine psychosocial correlates, were found to be eligible for the meta-analysis. For both tooth brushing and oral hygiene behaviour, random effect models revealed significant weighted average correlation (r + ) for the psychosocial factors: 'intention', 'self-efficacy', 'attitude' (not significant for tooth brushing), 'social influence', 'coping planning' and 'action planning' (r + ranging from 0.18 to 0.57). Little or no associations were found for 'locus of control', 'self-esteem' and 'sense of coherence' (r + ranges from 0.01 to 0.08). Conclusions: The data at present indicates that 'self-efficacy', 'intention', 'social influences', 'coping planning' and 'action planning' are potential psychosocial determinants of oral health behaviour. Future studies should consider a range of psychological factors that have not been studied, but have shown to be important psychosocial determinants of health behaviours, such as 'self-determination', 'anticipated regret', 'action control' and 'self-identity'. Effectiveness of addressing these potential determinants to induce behaviour change should be further examined by intervention trials. Despite great global improvements in oral health during the 21st century, oral diseases remain a major health problem 1,2 . According to the WHO report, dental caries affects approximately 60-90% of children and the vast majority of adults in developed countries 2 . The performance