Darier disease (DD) and Hailey-Hailey disease (HHD) are two rare genetic diseases sharing some clinical (recurrent inflammatory erythematous plaques with a predilection for the skin folds), histopathological (acantholytic dyskeratosis) and genetic (inherited as autosomal-dominant traits, mutations in genes encoding for Ca2+ ATPases, ATP2A2 for DD and ATP2C1 for HHD) similarities [1]. Here, ATP2A2 is linked to dentin dysplasia.