Gardner’s syndrome is a genetic disease which leads to a high chance of malignant degeneration in untreated patients. Typically, it presents intestinal polyposis, bone and mesenchymal tumors. The initial symptoms often appear in the head-neck area with osteomas, several dental anomalies, odontogenic tumors, exostosis and epidermoid cysts. In this sense, the role of odontologists and maxillofacial surgeons is of crucial importance in the early diagnosis of this syndrome, which is potentially fatal. A young female patient came to our attention with a slight swelling at the level of the right mandibular angle and a limitation of the mandibular movements. Dental panoramic showed atypical presence of deciduous teeth and an inflammation of dental sac surrounding the 4.8 tooth. Anamnesis revealed a family history of colon cancer. She referred irregular bowels, with occasional blood loss into the feces. Based on these informations, we hypothesize the diagnosis of Gardner’s syndrome. On our recommendation, the patient performed colon endoscopic examination, which showed the presence of multiple polyps, and a genetic screening of APC gene in the 5q21 locus, which confirmed our diagnostic hypothesis. Dental management was performed with 4.8 extractions and a complete orthodontic treatment. Gardner’s syndrome is a genetic disease which high incidence of malignant degeneration. The importance of an early diagnosis, even in all those cases where the typical clinical frameworks are missing, as in this case report, lies in the possible lethal outcome of this disorder, if not treated in the early stages. These examinations could save the patient’s life.