FGF23 and X-linked hypophosphatemia: In some countries, burosumab is now prescribed for certain conditions for children and adults affected by XLH.12 The therapy using FGF23 antibody was shown to improve growth and long bone osteomalacia in Hyp mice,13 and in humans.17,19,20 Our group recently reported a decrease in the incidence of dental abscesses in XLH children treated with burosumab for an average of 3.2 years compared to conventional treatment.21 However, a prospective case control study involving 10 children with XLH showed the persistence of enlarged pulp chambers, a hallmark feature of XLH, after 3 years of burosumab.22