RESUMO
Hypophosphatemic rickets is a rare genetic disorder involving the regulation of fibroblast growth factor 23 (FGF23), a phosphaturic agent, clinically showing bowing of the legs, short stature and dentoalveolar abscesses. A 7-year-old boy, with previous hypochondroplasia diagnosis, was referred to our pediatric dentistry clinic presenting short stature, bone deformities and sinus tracts at deciduous teeth apex levels not related with trauma, restorations or dental caries. After deciduous teeth extraction, due to root resorption and mobility, light microscopy exhibited typical hypophosphatemic dentin, and micro-computed tomography revealed tubular clefts and porosities throughout the teeth. Laboratory tests confirmed the HR diagnosis, after which the treatment was initiated.