Abstract
Objectives
Autosomal‐dominant hypocalcified amelogenesis imperfecta (ADHCAI) shows phenotypic heterogeneity. Our aim was to characterise the ADHCAI phenotypes, tooth properties, and genotypes.
Methods
Three unrelated ADHCAI probands and seven additional affected members of the three families were recruited. Mutations were identified by exome and Sanger sequencing, and haplotypes by SNP array. Tooth colour, roughness, density, nanohardness, minerals, and ultrastructure were investigated.
Results
Ten participants were heterozygous for the FAM83H mutation c.1387C>T (p.Gln463*). All shared a 3.43 Mbp region on chromosome 8q24.3 encompassing the FAM83H variant, indicating a common ancestry. The c.1387C>T was estimated to be 23.8 generations or 600 years. The FAM83H enamel had higher roughness and lower lightness, density, nanohardness, and calcium and phosphorus levels than controls. Blunted enamel rods, wide interrod spaces, and disorganized dentinoenamel junctions were observed. Evaluating the patients with the same mutation and reviewing others with different mutations in FAM83H revealed that the FAM83H heterogeneous phenotypes are age‐influenced. Tooth colour and surface texture change with aging.
Conclusions
FAM83H enamel demonstrated decreased lightness, density, hardness, calcium, phosphorus, and defective ultrastructure. We have identified that the phenotypic variation in FAM83H‐associated ADHCAI is age‐related. Awareness of the correlation between age and clinical features of FAM83H‐ADHCAI can help dentists make an accurate diagnosis.
