The effect of early childhood non-nutritive sucking behavior including pacifiers on malocclusion : a randomized controlled trial

Abstract

<p><strong>Background/rationale: </strong>Systematic reviews on the effects of pacifiers on occlusion have highlighted the need for quality RCTs.</p><p><strong>Trial design: </strong>Single region, three parallel-armed, prospective, randomized controlled trial.</p><p><strong>Objectives: </strong>To investigate the correlations between early childhood non-nutritive sucking habits and malocclusion. Specifically to test whether the use of a study pacifier has differing effects compared to other pacifiers and control, and whether the duration of pacifier use or digit sucking influence the occlusion.</p><p><strong>Participants: </strong>The subjects were firstborn children, born in 2008 in Vantaa, Finland.</p><p><strong>Intervention: </strong>One-third of participants were offered study pacifiers, free of charge, from birth up to 2 years of age. The history of the subjects' sucking habits, including pacifier use was screened in a questionnaire at the age of 2 years, and clinical examinations were performed at the age of 7 years. In addition, the subjects were divided into groups that were equally matched regarding their mother's level of education.</p><p><strong>Outcomes: </strong>Posterior crossbite, anterior crossbite, overjet, deep bite, open bite, and crowding.</p><p><strong>Randomization method: </strong>Three districts were randomly allocated to three study groups by drawing lots.</p><p><strong>Blinding: </strong>It was not possible to blind the clinicians or parents from the intervention. Blinding during data analysis was performed.</p><p><strong>Results: </strong>From the original cohort of 2715 children born in the town of Vantaa, 1911 were excluded and 353 were lost to follow-up. The remaining 451 children were divided into three groups according to the use of pacifiers. The prevalence of posterior crossbite at the age of 7 years was higher if a non-study pacifier had been used (P = .005) even when matched for the mother's level of education (P = .029). The prevalence of posterior crossbite was higher if the pacifier habit had continued for 12 months or more compared to 11 months or less, 7% and 1%, respectively, (P = .003). Digit sucking for 12 months or more was associated with crowding (P = .016). The prevalence of crossbite in the study pacifier group was less than in control pacifiers.</p><p><strong>Harms: </strong>No adverse harms were reported other than effects on the dentition.</p><p><strong>Conclusion: </strong>The use of pacifiers is associated with the posterior crossbite, especially if their use continues for a year or more. Parents/guardians should be advised to stop the use or reduce the use of pacifiers to a minimum after their child's first birthday.</p><p><strong>Trial registration: </strong>ClinicalTrials.gov <a href="http://clinicaltrials.gov/show/NCT01854502" title="See in ClinicalTrials.gov">NCT01854502</a>.</p>