He studied at the University of Montpellier and settled around 1529 in Rodez where he served as lieutenant to the King's First Surgeon for his colleagues in the Sénéchaussée and the Diocese of Rouergue.
[1][2][3] He was one of the doctors of Rodez called in 1586 to the bedside of Margaret of Valois, who had taken refuge in the castle of Carlat after her rupture with her family and the King of Navarre, the future Henri IV.
In 1582, Hémard dedicated his book Recherche de la vraye anathomie des dents, nature et propriété d'icelles (Research into the true anatomy of the teeth, their nature and properties) to the Cardinal, preceded a few months ahead by an Essay sur les dents (Essay on Teeth).
Indeed, using his status as consul, he facilitated the entry into the city of soldiers of the League against the advice of his rather royalist fellow citizens.
[4] The book Recherche de la vraye anathomie des dents, nature et propriété d'icelles consists of twenty-three chapters: the first three are devoted to the names, nature and properties of the teeth, the next three to "feeling", the next seven to the development of the teeth, four of which deal with odontogenesis and three with tooth eruption, and finally the last ten deal with dental diseases, four of which are therapeutic and the last with prophylaxis.