Effectiveness of adding an antibacterial agent (Povidone iodine or Chlorhexidine) to fluoride varnish on caries prevention among 4–6-year-old school children – A randomized controlled trial

Background: Dental caries is a major public health problem worldwide and there exists a relationship with nutritional status, overall growth and development of the child. Recent advancements in preventive dentistry advocate use of an antibacterial agent with topical fluoride to prevent caries incidence effectively. Novelty: Paucity of good quality randomized trials evaluating the added benefit of chlorhexidine or povidone iodine over topical fluoride use alone limits our ability to frame effective caries preventive guidelines for children. The results of this randomized trial will thus help us formulate an effective caries preventive regimen for children. Objectives: To assess and compare the caries preventive effectiveness of antibacterial agent (povidone iodine or chlorhexidine) plus fluoride varnish over fluoride varnish alone among 4–6-year-old children. To correlate the tooth morbidity and nutritional status of the children. Methods: Children will be randomly allocated to one of the three groups (Group 1: 1% chlorhexidine solution followed by 5% fluoride varnish, Group 2: 10% povidone iodine solution followed by 5% fluoride varnish, Group 3: placebo solution followed by 5% fluoride varnish). The three formulations (10% povidone iodine, 1% chlorhexidine and placebo) will be masked indigenously to ensure triple blinding. ICDAS II scores, DIAGNOdent/QLF scores, gingival bleeding index, BMI, and oral microflora including Mutans streptococci will be evaluated at baseline and at follow-ups up to 2 years. Appropriate descriptive and inferential statistics will be applied. Statistical significance is set at p<0.05. Expected outcome: This trial will help evaluate whether semi-annual application of antibacterial agent (povidone iodine or chlorhexidine) along with fluoride varnish is more effective in preventing caries than fluoride varnish application alone among 4–6-year-old children. Caries preventive potential will be assessed through change in dental caries increment and oral microflora in saliva over a two year follow up period. Correlating the BMI and dental caries incidence in children could be useful to determine the effect of tooth morbidity on overall growth of the children and indicate the need for intersectoral coordination for health promotion.