OBJECTIVE: The aim of this study was to identify the expression of nitric oxide synthases (NOS) in the mandibular condyle during mandible advancement by functional appliance and to correlate it with the histologic changes and bone remodeling. METHODS: Twenty-four female, 35-day-old Sprague-Dawley rats were randomly divided into 3 experimental groups. In all experimental groups, the mandibles of the rats were kept in a continuous forward position with a fixed bite jumping appliance. The rats were sacrificed on the 3rd, 14th, and 30th days of experiment. More than 2 rats in each group were used for staining. RESULTS: There were no remarkable histologic changes and NOS expression differences in the control group. The most prominent histologic changes occurred in the 14th day experimental group. NOS decreased in the 30th day experimental group. There was increased expression of NOS2 and NOS3 in all experimental groups, comparative to the control group. In all the experimental groups and control group, the expression of NOS2 was greater than that of NOS3. CONCLUSIONS: It is postulated that NOS2 and NOS3 in the mandibular condyle might play an important role in bone remodelling of the mandibular condyle.
Animals ; Bites and Stings ; Bone Remodeling ; Female ; Humans ; Mandible ; Mandibular Condyle ; Nitric Oxide ; Rats ; Rats, Sprague-Dawley