Impact of parental psychosocial profile on the effectiveness of oral hygiene interventions in preschool children: a randomised controlled clinical trial in a rural population

Abstract Objective To assess the impact of parental psychosocial profile on the effectiveness of educational interventions aiming to improve oral hygiene among preschool children living in a rural area. Methods A controlled randomised trial (RBR-44nrnjz, March 5, 2023) was conducted with 78 preschool children and their caregivers residing in a rural area in southern Brazil. The participants were randomly assigned to two intervention groups: standard guidance (SG) and the teach-back technique (TB). The study comprised three phases: baseline (oral examination and data collection), Phase I (educational intervention), and Phase II (oral examination seven days post-intervention). Oral hygiene was assessed using the visible plaque index (VPI) and the Simplified Oral Hygiene Index (OHI-S). For OHI-S assessment, a mature dental biofilm (> 24 h) was identified with a disclosing agent. Psychosocial factors were assessed using the sense of coherence (SOC) and parental locus of control (PLOC) instruments. For statistical analysis, participants were categorised into two clusters: Cluster 1 (lower SOC and higher internal PLOC) and Cluster 2 (higher SOC and lower internal PLOC). Data were analysed using non-parametric tests. Results A reduction in the number of teeth with visible plaque was observed only among participants in Cluster 1 subjected to the TB intervention. OHI-S scores decreased, regardless of the caregivers’ psychosocial profile or the type of intervention. Conclusion The psychosocial profile of caregivers did not affect the effectiveness of oral health educational interventions when a mature dental biofilm was considered.