AMELOGENESIS IMPERFECTA
It is a group of hereditary defect unassociated with any other generalized
defect or systemic disorder.
It is entirely an ectodermal disorder
CAUSED BY:
Alteration of genes involved in the process and maturation of enamel.
AMELX : associated with amelogenin
AMELX gene is a t the locus of DXS 85 in chromosome Xp22.
ENAM : associated with enamelin
DLX3
KLK4
MMP 20
CLASSIFICATION:
WIKTOP CLASSIFICATION (1989)
TYPE I: HYPOPLASTIC
I A Hypoplastic, pitted autosomal dominant
I B Hypoplastic, local autosomal dominant
I C Hypoplastic, local autosomal recessive
I D Hypoplastic, smooth autosomal dominant
I E Hypoplastic, smooth X linked dominant
I F Hypoplastic, rough autosomal dominant
I G Enamel agenesis, autosomal recessive
TYPE II: HYPOMATURATION
II A Hypomaturation, pigmented autosomal recessive
II B Hypomaturation, X linked recessive
II C Snow capped teeth, autosomal dominant
TYPE III: HYPOCALCIFIED
III A Autosomal dominant
III B Autosomal recessive
TYPE IV: HYPOMATURATION – HYPOPLASTIC WITH TAURODONTISM
IV A Hypomaturation – hypoplastic with taurodontism: autosomal
