Recurrent aphthous aphthous stomatitis (RAS) are painful oral ulcertations that recur from days to months or even yours. It represents the most common lesion of the oral mucosa with prelalenceranging from 15% to 30%. Altough the clinical characteristics of RAS are well defined, the precise etiopathogenesis of RAS remains unclear. Since the etiology of RAS remains unknow, there is no definitive …