Marfan syndrome is the most common dominant autosomic genetic disorder of the connective tissue. It has a reported incidence of 1 per each 5000 individuals without any distinction of gender or ethnicity. This pathology?s diagnosis is mainly based on physical characteristics, presenting three main different symptomatic charts: neonatal Marfan, infant Marfan and classical Marfan. The mayor characteristic of these patients consists of an exaggerated length of the upper and lower limbs, hyperlaxity, scoliosis, alterations in the cardiovascular and pulmonary systems and atypical bone overgrowth. The individual implied in the present investigation concerned to a 14 year old male patient presenting multiple mouth lesions and dental alterations, attended in the Department of Pediatric Dentistry degree at the Dentistry School in the Santa Maria University. The patient has been treated following the necessary considerations required according to his systemic compromise d under oral premedication for decrease the anxiety and make easear the behavior management. The patirnt with MS has multiple oral decrease that may be diagnoticated a treated on time to increase the life quality of the patient.