Abstract: PURPOSE: To evaluate the effect of functional occlusal device in the fenestration of jaw cyst. METHODS: Fifty patients with jaw cyst who underwent fenestration surgery for the first time were selected. According to the treatment methods, they were divided into the conventional treatment group and functional treatment group, with 25 cases in each group. Obturator functioning scale (OFS) was used to evaluate the comfort, masticatory efficiency and aesthetics of patients wearing two kinds of different endodontics during fenestration treatment. The patients' satisfaction with the final restoration was investigated by questionnaire. SPSS 20.0 software package was used for data analysis. RESULTS: Compared to conventional obturators, the functional obturator group showed a statistically significant reduction in mandibular and maxillary tooth extension after healing of the lesion (P<0.01). However, there was no significant difference in chewing efficiency during the wearing of the obturator(P>0.05). The esthetic satisfaction of the functional obturator was significantly higher in patients with anterior tooth loss(P<0.01). CONCLUSIONS: The functional obturator, which combines the functions of denture restoration, not only has good esthetics and wearing comfort, but also better maintains stability in missing interdental spaces and is more favorable for the restoration of missing teeth.

Key words: Odontogenic cyst, Marsupialization, Obturator