Molar Incisor Hypomineralization (MIH) is a common developmental enamel defect affecting children, particularly in Dubai, where it contributes to hypersensitivity, esthetic concerns, plaque accumulation, and increased caries risk. These complications often lead to premature tooth extraction and orthodontic issues, negatively impacting children's oral health-related quality of life.

This randomized, open-label clinical trial aims to compare the remineralization efficacy of a fluoride-free hydroxyapatite toothpaste with a conventional fluoride toothpaste in children aged 6-12 years diagnosed with mild to moderate MIH.

Participants will be recruited from Dubai Health pediatric dental clinics, with inclusion criteria requiring at least one affected permanent molar or incisor, good general health, parental informed consent, and the child's assent. Children with systemic conditions affecting enamel or recent use of desensitizing treatments will be excluded.

Primary outcome assessment will involve Quantitative Light-Induced Fluorescence-QLF at baseline, 3, 6, 9, and 12 months. The images were analyzed using a commercial software program (Inspektor QLF 1.97, Inspektor Research Systems, Amsterdam, The Netherlands) to determine the change in fluorescence (ΔF, %) and extension of the lesion (area; mm2).

Secondary outcome measures will include enamel fluorescence readings using the DIAGNOdent Pen. After prophylaxis and air-drying, three readings per lesion will be recorded, with mean and peak values analyzed to monitor mineralization. Hypersensitivity in MIH-affected teeth will be assessed using air stimulus (Schiff scale) and Visual Analogue Scale (VAS) at baseline, 3, 6, 9, and 12 months. Oral health-related quality of life (OHRQoL) will be measured using age-appropriate validated questionnaires to evaluate the impact of MIH and treatment over time.

This study also responds to growing parental concerns about fluoride exposure and the demand for safer, fluoride-free alternatives. By evaluating the clinical effectiveness of hydroxyapatite toothpaste, the trial aims to inform evidence-based preventive strategies for MIH management. The findings may guide clinical practice and public health recommendations, ultimately improving oral health outcomes for affected children.

Molar Incisor Hypomineralization (MIH) affects approximately 13-14% of children globally. It is a developmental enamel defect with multifactorial etiology, including perinatal and early childhood illnesses. Clinically, MIH leads to hypersensitivity, enamel breakdown, and increased caries risk, significantly impacting oral health-related quality of life. Remineralization strategies using fluoride and biomimetic agents like hydroxyapatite (HAP) have shown promise. HAP offers comparable efficacy to fluoride with added benefits and fewer risks.

Molar incisor hypomineralization (MIH) is a qualitative enamel defect affecting up to 14% of children globally. It is associated with enamel breakdown, hypersensitivity, and increased caries risk. Fluoride is widely used for remineralization but carries risks like fluorosis. Hydroxyapatite (HAP), a biomimetic agent, has shown comparable efficacy in caries prevention and remineralization. However, there is a lack of in vivo clinical trials comparing HAP and fluoride for MIH management in children. This study addresses the need for safer, effective alternatives to fluoride in pediatric dentistry.

Inclusion Criteria:

• at least one affected permanent molar or incisor
• good general health
• parental informed consent, and the child's assent

Exclusion Criteria:

• Patients with systemic conditions affecting enamel or recent use of desensitizing treatments.