Glass Ionomer Cement Sealant in the Prevention of Post-eruptive Fractures in Molars Affected by MIH

This trial will compare the application of Glass Ionomer Cement (GIC) sealant with no-intervention for the most clinically- and cost-effective strategy for managing MIH molars without post-eruptive breakdown, in a school setting, using low-technology and child-friendly dental techniques. Methods/Design: This two-arm, parallel group, patient-randomized controlled, superiority trial will have treatment provided in schools. Schoolchildren (age 6-9), presenting at least one MIH molar (n molars = 195,) will have random allocation to treatment with or without the application of a GIC sealant (GC Fuji TRIAGE®, GC Europe, Leuven, Belgium). Baseline measures and outcome data will be assessed through participant report and clinical examination. The primary outcome is the presence of post-eruptive fracture and development of caries lesions. Secondary outcomes are: (1) self-reported dental hypersensitivity; (2) oral health-related-quality of life, reported by children; (3) plaque index, (4) gingival health, (5) caries status (according to ICCMS scores) in primary and permanent teeth; (6) the incremental cost-effectiveness. A trained and calibrated examiner will evaluate the treated teeth every six months post treatment for a period of 36 months. Kaplan-Meier and Cox regression tests will be used to investigate the primary outcome. The Logistic Regression and Poisson Regression Analysis will be used to analyze the secondary outcomes (α=5%).

Background: Molar-Incisor Hypomineralisation (MIH) is defined as a qualitative defect that occurs during the mineralization phase of enamel of at least one first permanent molar. The opacities vary in size and color and are demarcated by healthy enamel. MIH molars present lower mechanical properties when compared to non-affected molars, due to the enamel's decreased mineralization. Allied to that, patients often report dental hypersensitivity, which impairs the mechanical removal of dental plaque; therefore, those molars are more prone to post-eruptive fractures and present higher risk of developing dental caries. This trial will compare the application of Glass Ionomer Cement (GIC) sealant with no-intervention for the most clinically- and cost-effective strategy for managing MIH molars without post-eruptive breakdown, in a school setting, using low-technology and child-friendly dental techniques. Methods/Design: This two-arm, parallel group, patient-randomized controlled, superiority trial will have treatment provided in schools. Schoolchildren (age 6-9), presenting at least one MIH molar (n molars = 195,) will have random allocation to treatment with or without the application of a GIC sealant (GC Fuji TRIAGE®, GC Europe, Leuven, Belgium). Baseline measures and outcome data will be assessed through participant report and clinical examination. The primary outcome is the presence of post-eruptive fracture and development of caries lesions. Secondary outcomes are: (1) self-reported dental hypersensitivity; (2) oral health-related-quality of life, reported by children; (3) plaque index, (4) gingival health, (5) caries status (according to ICCMS scores) in primary and permanent teeth; (6) the incremental cost-effectiveness. A trained and calibrated examiner will evaluate the treated teeth every six months post treatment for a period of 36 months. Kaplan-Meier and Cox regression tests will be used to investigate the primary outcome. The Logistic Regression and Poisson Regression Analysis will be used to analyze the secondary outcomes (α=5%).

Eligibility Criteria:
Inclusion criteria:

* children whose parents or legal guardians accept and sign the informed consent form; -children who assent to participate into the research;
* aged between 6 and 9 years;
* exhibiting good general health conditions and cooperative behavior;
* presenting at least one MIH molar.

Exclusion criteria:

* children presenting health conditions that impair the dental treatment, or children undergoing orthodontic treatment;
* MIH molars that present opacities not located on the occlusal surface, with post-eruptive breakdown, with the occlusal surface totally or partial covered by a gingival operculum, with caries dentine lesion (ICCMS score C), restorations or sealants.