Patients with multiple pathologies are a high-risk group, which requires a personalized approach to surgical rehabilitation in dentistry. Inadequate diagnosis of clinical manifestations when a patient is in remission often leads to severe surgical complications. However, modern methods of dental implantation and rehabilitation are possible even in patients with oncology, those who underwent surgical therapy, chemo- or radiotherapy. Gilbert syndrome, one of the risk factors for post-surgery inflammatory complications, is associated with defects in bilirubin metabolism. It inhibits platelet activity. It is a genetic disease leading to a loss of liver enzyme activity and the accumulation of indirect bilirubin that can aggravate the course of other diseases in patients. In acute stages, it is characterized by jaundice of the skin, eyes, and mucosa and is followed by immunosuppression and the post-surgical complications associated with it. A patient with Gilbert syndrome was administered for surgical treatment of a chronic infection and follow-up rehabilitation via dental implantation and reconstruction of the bone. In this case, we faced Gilbert syndrome in association with polycythemia (a myeloproliferative disease in the compensation stage). In such cases, dental implantation cannot be achieved in the complex dental rehabilitation process. Such diseases require special attention from dental surgeons due to possible complications (bleeding, thrombosis, or disseminated intravascular coagulation). In this specific case, the patient belongs to the risk group, and its history, although in remission, is still a contraindication for dental surgery and dental implantation.