Amelogenesis imperfecta: enamel ultra structure and molecular studies

Amelogenesis imperfecta (AI) is a hereditary disorder resulting in generalized defects in the enamel.The case

reported here is of a seven-year-old male child with yellow color of all his teeth.Two of his primary molars

were extracted due to dental abscess with advanced root resorption. Histologically hypoplastic enamel layer,

positively birefringent, generalized pitting, roughness with irregular general cracked borders were observed.

Scanning electron microscope, revealed extensive irregular, disorganized rough superficial enamel layer.The

enamel was irregularly decussate with filamentous prisms accompanied by small rounded formations. The

morphological and histological examination of the tooth revealed that this patient has the features of AI.For

genetic study blood sample were collected from the patient and PCR analysis revealed that there is no mutation

in exons 1-7 of AMELX gene on the X chromosome of the patient. Hence, it is probable that the AI of

this patient is not X-linked. It is more likely to be an autosomal mutation.

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