[Histological and ultrastructural variations after radiofrequency for soft palate in porcines].
OBJECTIVE
To investigate the histological and ultrastructural variations after radiofrequency volumetric reduction of the soft palate in an animal model.


METHODS
Thirteen porcines were used to evaluate the tissue response to radiofrequency for various time periods. They were divided into two groups. Group 1 was exposed to radiofrequency in the midline of the soft palate with a constant energy of 2.4 KJ. Group 2 served as a control group. The animals in group 1 were sacrificed after 1 hour, 24 hours, 48 hours, 72 hours, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks and 9 weeks, respectively, and after 72 hours, 2 weeks and 4 weeks for the animals in group 2. Then the soft palates from both groups were examined for histological and ultrastructural variations.


RESULTS
Interstitial edema, hemorrhage and infiltration with inflammatory cells were observed in the early acute stage after radiofrequency, and then the neovascularization of the forming scar was observed. In the end, the injured tissue was replaced by collagenous fibers. Intact vessels and nerves were observed around the lesions.


CONCLUSIONS
After radiofrequency, lesion tissue is replaced by collagenous fibers, and it is focused on the lesion site. These findings may help provide a basis for technological suggestion in regard to clinical treatment.
Xu
Yuan-jin
YJ
Department of Oral and Maxillofacial Surgery, School of Stomatology, Ninth People's Hospital, Shanghai Second Medical University, Shanghai 200011, China.
Zhang
Zhi-yuan
ZY
Lu
Xiao-feng
XF
Shen
Guo-fang
GF
Tang
You-sheng
YS
D000818:Animals; D010160:Palate, Soft / Q000473:pathology* / Q000528:radiation effects / Q000648:ultrastructure; D013552:Swine