Molar incisor hypomineralisation in relation to fat-soluble vitamin status and intestinal permeability in children with celiac disease.

Background: Celiac disease (CD) is a systemic autoimmune enteropathy triggered by gluten ingestion that frequently manifests with extra-intestinal complications, including enamel defects. Molar incisor hypomineralisation (MIH) has been proposed as a dental marker of systemic mineral dysregulation; however, its association with fat-soluble vitamin deficiencies in children with celiac disease remains insufficiently characterised. Methods: A prospective pilot case-control study was conducted over 12 months including 70 children (35 with confirmed CD, 35 healthy controls). MIH severity was graded using a validated four-point scale; enamel defect extent was scored using the Aine classification. Serum levels of vitamins K1, K2, and D, zonulin, calcium, phosphorus, alkaline phosphatase, and oral hygiene indices (Löe Plaque Index; OHI-S) were recorded. An exhaustive statistical analysis was conducted using these parameters. Results: MIH was detected in 27/35 CD children (77.1%) versus 0/35 controls. Vitamin K2, vitamin D and serum calcium were significantly lower in CD. Strong negative correlations were observed between MIH severity, vitamin K2 and vitamin D. ROC analysis revealed excellent diagnostic performance of zonulin, vitamin K2, and vitamin D for discriminating CD status. Conclusion: Children with celiac disease exhibited a higher prevalence and greater severity of molar-incisor hypomineralisation, which was associated with lower vitamin K2 and vitamin D levels. Zonulin, vitamin K2, and vitamin D also showed promising discriminatory ability for identifying children with celiac disease; however, given the pilot nature of the study, these findings should be considered exploratory and require validation in larger multicenter cohorts.