Long-term evaluation of the success rate of different treatment modalities on MIH-affected teeth

The objective is to report on long-term success of treatment modalities of MIH-affected teeth and correlate them with patient- and teeth-related factors.

A retrospective cohort study on MIH teeth involving data collection from the patients' dental records regarding initial treatment performed and evaluation of treatment success and need for re-treatment up to 24 months post-treatment. Fisher's exact test and non-parametric Cuzik trend test were used to test changes in treatment and multinomial logistic analysis to investigate the effect of patient and tooth-related characteristics. Analyses were performed using STATA 18.

The sample consisted of 38 patients, with a mean age of 9 years at presentation. The vast majority had all four molars affected and 30% had up to two incisors. More than half of MIH teeth were severely affected (57%), showed enamel breakdown (57%) and were decayed (74%). The most common treatments performed were stainless steel crowns (34%) and composite resin restorations (27%). Treatment was successful in most cases up to 24 months post-treatment (p-values 0.05). Up to 12 months, restorations in eight teeth were rated with a Charlie/Delta mainly due to loss of marginal integrity and discoloration. Repeat of the same treatment was performed in 13 teeth, with most repeats being for sealants and preventive resin restorations. No significant correlation existed between the outcome and demographic characteristics and clinical features.

Type of treatment is directly associated with the severity of hypomineralization, with both direct and indirect restorations showing equally high success rates. They can therefore be considered effective restorations with acceptable clinical performance.