Molar incisor hypomineralization : from awareness among Hong Kong dentists to mineralization using silver diamine fluoride

Abstract

Molar incisor hypomineralization (MIH) is a condition which presents as well-demarcated areas of hypomineralized enamel on the first permanent molars and incisors (Weerheijm, 2001). The prevalence of MIH in the Hong Kong Chinese population is 2.8% (Cho et al., 2008). The affected teeth have compromised physical and chemical properties presenting with complex problems which complicate the management of patients affected with such condition.

The first study is a cross-sectional survey aiming to evaluate and compare the knowledge, perceptions, and clinical experiences of molar incisor hypomineralization (MIH) between the general dental practitioners (GDPs) and paediatric dentists (PDs) practicing in Hong Kong. A sample of 557 GDPs (approximately 25% of all registered dentists) and all registered PDs (n=31) were recruited to participate in the study. Participants were asked to complete a questionnaire adapted and modified from a study by Gambetta-Tessini et al. (2016). A higher mean knowledge score was observed for PDs when compared to GDPs. Differences in the treatment of MIH have also been observed between the two groups. Most dental practitioners have also expressed a need for continuing education on MIH.

The second study aimed to evaluate the mineralizing potential of silver diamine fluoride (SDF) solution on developmentally hypomineralized enamel from first permanent molar teeth. Eight extracted first permanent molar teeth affected with molar incisor hypomineralization (MIH) were randomly assigned into one of the two experimental groups. Four teeth were pre-treated with 5.25% sodium hypochlorite (NaOCl) solution prior to application of 38% SDF solution; while the other four teeth did not receive any pre-treatment. All teeth were immersed in remineralizing solution for fourteen days. The mineral content of the lesions was assessed prior to and after NaOCl and SDF treatment, using micro-computed tomography. Results from the study showed that topical application of 38% SDF solution is effective in mineralizing hypomineralized enamel lesions from MIH-affected teeth. Pre-treatment with 5.25% NaOCl did not improve the effectiveness of 38% SDF solution as a mineralizing agent.