We present a unique comparison of cone-beam computed tomography (CBCT) and intraoperative view of the accessory infraorbital foramen and nerve in a 60-year-old woman who was surgically treated due to the giant dentigerous cyst of the maxillary sinus from ectopic upper third molar. CBCT imaging demonstrates highest level of accuracy in verification of the accessory infraorbital foramina what makes this imaging technique a perfect tool for the surgery planning in the area of middle face. Avoidance of iatrogenic trauma of both infraorbital and accessory nerves will be ensured significantly in professionals who understand this topic. Oral and maxillofacial surgeons and doctors of neighboring specialties should be aware of such unusual anatomic variation as unilateral or even bilateral accessory infraorbital foramina and intraosseous nerve ramification.