Frequency of molar incisor hypomineralization and associated factors among children with special health care needs.

BACKGROUND: Molar incisor hypomineralization (MIH) is a frequently encountered oral condition that varies from mild opacities to posteruptive enamel breakdown. No previous published studies have investigated the frequency of MIH and associated risk factors among children with special health care needs (CSHCN) to our awareness. OBJECTIVES: Assess the frequency of MIH and associated risk factors among CSHCN. DESIGN: Cross-sectional. SETTING: Schools in provincial city of Saudi Arabia. PATIENTS AND METHODS: The study was conducted among 400 (180 boys and 220 girls) special needs children. Diagnosis of MIH was according to the European Academy of Paediatric Dentistry criteria. MAIN OUTCOME MEASURE: Result of logistic regression analysis that assessed the association between MIH prevalence and associated prenatal, perinatal, and postnatal factors. SAMPLE SIZE: 400 (180 boys and 220 girls) special needs children. RESULTS: Among 400 CSHCN, 98 (24.5%) presented with MIH. Children with multiple disabilities had a 3.89 times greater risk of MIH (95% CI: 1.91-6.19, P=.002). Children with positive prenatal factors had an adjusted odds ratio (aOR) of 2.31 times for MIH (95% CI: 1.22-4.73, P=.012). Children with a childhood infection history had an aOR of 2.43 times for MIH (95% CI: 1.31-5.85, P=.014). Children with a breastfeeding history >18 months had an aOR of 3.73 for MIH (95% CI: 1.62-8.60, P=.002). Permanent maxillary first molars were the most frequently affected teeth, and demarcated opacity was the most frequent MIH type. CONCLUSION: MIH should be recognized as one of the prevalent oral health problems among CSHCN to prevent tooth mortality. LIMITATIONS: A cross-sectional study cannot establish a causal relationship. CONFLICTS OF INTEREST: None.

Genome-wide gene expression profiling and mutation analysis of Saudi patients with Canavan disease.

PURPOSE: Canavan disease, caused by a deficiency of aspartoacylase, is one of the most common cerebral degenerative diseases of infancy. The aims of this study were to identify the mutations associated with Canavan disease in Saudi Arabia and to identify differentially expressed genes likely to contribute to the development of this disease. METHODS: Polymerase chain reaction, long polymerase chain reaction, multiplex ligation-dependent probe amplification, sequencing, array comparative genomic hybridization (aCGH), and global gene expression profiling were used to determine putative mutations and likely gene signatures in cultured fibroblasts of patients from Saudi Arabia. RESULTS: One novel and one known large deletion and two previously known mutations (IVS4 + 1G>T and G27R) were identified. Compared with controls, 1440 genes were significantly modulated in Canavan patients (absolute fold change [FC] > or =4). Genome-wide gene expression profiling results indicated that some genes, involved in apoptosis, muscle contraction and development, mitochondrial oxidation, inflammation and glutamate, and aspartate metabolism, were significantly dysregulated. CONCLUSIONS: Our findings indicate that the presence of muscle weakness and hypotonia in patients may be associated with the dysregulated gene activities of cell motility, muscle contraction and development, actin binding, and cytoskeletal-related activities. Overall, these observations are in accordance with previous studies performed in a knockout mouse model.