Purpose: Hypersensitivity is a frequent complaint in children with molar incisor hypomineralisation (MIH). This double-blind randomised controlled trial aimed to evaluate non-inferiority in hypersensitivity relief of a toothpaste containing microcrystalline hydroxyapatite compared to amine fluoride in children with MIH.
Materials and Methods: Children were randomised into 2 groups: either hydroxyapatite (intervention) or amine fluoride toothpaste (control). The primary endpoint was pain sensation in response to tactile stimulus (Wong-Baker FACES Pain Rating Scale) 56 days after randomisation and analysed by mixed effects linear regression analysis. Non-inferiority was inferred if the upper limit of the one-sided 95% confidence interval (CI) of the difference between intervention and control group was below the non-inferiority margin of 1 in the ITT (intention-to-treat) and PP (per protocol) population.
Results: Twenty-one children were randomised and 14 children finished the study per protocol. In the ITT population, hydroxyapatite was non-inferior to amine fluoride (mean difference: -0.75 95%CI [-∞;0.49]). In the PP population, non-inferiority could not be shown (-0.62 [-∞;1.08]).
Conclusions: Overall non-inferiority in hypersensitivity relief of a toothpaste containing hydroxyapatite compared to amine fluoride could not be shown. However, the hydroxyapatite group tended to be less hypersensitive in both populations. Attrition of the PP population due to the COVID-19 pandemic led to loss of statistical power.
Keywords: children, hydroxyapatite, hypersensitivity, fluoride, molar incisor hypomineralisation (MIH)