The medical history of a 46-year-old man recorded osteomas in the maxillary bone 18 years before, haemorrhoids, and kidney stones. He presented with pain in the right lower abdomen and rectal blood loss. His complaints were diagnosed as familial adenomatous polyposis, culminating in sigmoid carcinoma. Due to the extent of the polyps and, consequently, the great cancer relapse risk, a surgical treatment was indicated. A symptom of a familial adenomatous polyposis variant, Gardner’s syndrome, is osteomas in the orofacial region. Dentists and oral surgeons should be aware of this rare syndrome in a patient with orofacial osteomas, especially if the patient has a familial risk of adenomatous polyposis.