Restoration of teeth affected by molar-incisor hypomineralisation: a systematic review

The objective was to systematically analyse clinical studies on restorative procedures for teeth affected by molar-incisor hypomineralisation (MIH). The databases PubMed, Embase, and Cochrane Library were searched. Only retrospective and prospective clinical studies dealing with sealing or restoration of MIH-affected teeth were included. The language was restricted to English or German. Thirteen of 36 potentially eligible studies were included focusing on the following subjects: extension of enamel preparation, adhesive procedures prior to restoration, application of fissure sealants as well as restoration with conventional glass ionomer cements (GIC), resin modified glass ionomer cements (RMGIC), resin composites, and indirect restorations. Seven clinical studies were controlled trials. However, only two included MIH-unaffected teeth as control. No meta-analysis was performed due to the heterogeneity of study designs (e.g. severity of MIH or the restorative materials investigated). Based on the present analysis, the annual failure rates were in average 21% for fissure sealants, 22% for GIC, 1-6% for RMGIC, 13-32% for resin composites, and 0-7% for indirect restorations. In summary, only few tendencies can be deduced from this review at a low level of evidence (number of studies): 1) preparation margins in sound enamel seem to be superior to preparations in hypomineralised enamel (1 study), 2) RMGIC seems to be superior to GIC (3 studies), 3) resin composites may be used for restoring all severities of MIH (7 studies) with self-etch and etch-and-rinse adhesive systems generally not performing differently (3 studies), and 4) in cases of severe MIH, indirect restorations showed a good clinical success (4 studies).