People United States of America John Ross Callahan peoplepill id: john-ross-callahanJRC 7 views today 11 views this weekAmerican dentist, dental researcherJohn Ross CallahanBiographyListsAlso ViewedListsJohn Ross Callahan is in following listsBy field of workNotable American people in healthcare and medicineGender:Male, Born in:Years 1850 to 1899By work and/or countryNotable American DentistsGender:Male, Born in:Years 1850 to 1899From our partnersSponsoredJohn Ross Callahan
