The radicular cyst is the most common odontogenic cyst and is caused by inflammation. It can become atypically large, although the size of the radiographic osteolysis says nothing about the entity of the lesion. This case shows an unusually large multilocular radicular cyst expanding buccally from tooth 46 in a patient with severe autism who can only be treated under general anesthesia. The clinical and radiological picture as well as the intraoperative situation was more indicative of an aggressive cyst or benign tumor. The lesion was surgically completely removed and the teeth 46, 47 and 48 were extracted because of poor compliance and prognosis. Histopathology revealed a radicular cyst. There were no postoperative complications. After eight months, the lesions had almost completely reossified.

This case report illustrates a new application of autologous dentin for defect augmentation. After cystectomy of a follicular cyst in the maxilla, autologous particulated dentin from the wisdom tooth is used for augmentation due to periodontal compromise of neighbouring teeth. The combination of simultaneous wisdom tooth removal and augmentation is a convenient option in this case. Dentin augmentation is a cost-effective and minimally invasive autologous graft technique. The decision which treatment method for a jaw cyst is the most effective for the patient is a well discussed topic. Factors as expansion, type of cyst, localisation, duration of treatment, and predictability have to be calculated when choosing the treatment strategy. Most cysts heal without grafting, however, periodontal situation, sinus association and predictability in aesthetics led to the decision of grafting necessity in this presented case.

The dentigerous cyst is the second most frequent odontogenic cyst after the radicular one. Typically, dentigerous cysts are asymptomatic and are commonly diagnosed incidentally. Due to the slow, expansive growth dentigerous cysts have the potential for dislocation of adjacent structures (neighbouring teeth, canalis retromolaris), root resorptions and in an extreme case could cause jaw fractures. A histological examination represents a sine qua non, because other more alarming pathologies (odontogenic keratocyst, unicystic ameloblastoma, myxoma, primordial odontogenic tumour etc.) can exhibit clinically and radiologically a similar appearance. This brief overview aims to illustrate, by two clinical cases, the examination, the diagnosis and decision-making for either a cystostomy or a cystectomy. The surgical procedure of both techniques is presented in a step-by-step manner.