Diagnosis and treatment of congenital submandibular duct dilatation / 华西口腔医学杂志

OBJECTIVE@#To study the clinical features and treatments of congenital submandibular duct dilatation.@*METHODS@#Seven children with congenital submandibular duct dilatation from January 2008 to March 2018 were included in this study, whose average age was 5 months and 22 days. The clinical manifestations are unilateral swelling of the mouth floor. All seven children underwent sublingual gland resection, submandibular gland dilatation catheter resection, and catheter reroute under general anesthesia. Intraoperatively, the orifice of the submandibular gland was constricted and part of the catheter was dilated.@*RESULTS@#All seven patients had good healing without swelling or cyst formation.@*CONCLUSIONS@#Congenital submandibular duct dilatation occurs at a young age. Early diagnosis and treatment can help prevent further expansion of the catheter and avoid gland atrophy, feeding difficulty, and breathing obstruction. Simultaneous excision of the sublingual gland can avoid the formation of postoperative sublingual cyst.

Study on the in vitro effects of dexamethasone at different concentrations on the growth of murine embryonic palatal mesenchymal cell / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To observe the effect of dexamethasone on the proliferation and apoptosis of embryonic palatal mesenchymal (EPM) cells, and chose a proper concentration of dexamethasone which can effect the ordinary growth of embryonic palatal mesenchymal cells.</p><p><b>METHODS</b>The primary EPM cells were isolated and cultured in vitro, then we did biological assay. EPM cells were treated with different concentration dexamethasone (1 x 10(-9), 1 x 10(-8), 1 x 10(-7) and 1 x 10(-6) mol x L(-1)) respectively. The proliferation of EPM cells was evaluated using MTT method. Apoptosis was examined quantitatively with fluorescein stain.</p><p><b>RESULTS</b>In the condition of blood serum's concentration at 10%, optical density step down following the raise of dexamethasone's concentration. The effect of dexamethasone got to a summit at 3 days. Inhibition rate of dexamethasone at 1 x 10(-6) mol x L(-1) was the highest.</p><p><b>CONCLUSION</b>Dexamethasone at 1 x 10(-6) mol x L(-1) can not only inhibit the growth of the EPM cells, but also will not lead to a large number of cells death. Therefore, this concentration can be used as a reference standard in future research. The most significant drug action time of dexamethason appears at the third day after administration, then the effect became weaken following the drug metabolism.</p>

Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>This study aimed to explore the effects of different types of palatal lateral excisions on the growth and development of the maxilla and dental arch, and to investigate the underlying mechanisms.</p><p><b>METHODS</b>A total of 112 3-week-old Sprague-Dawley (SD) male rats were randomly divided into a control and 3 experimental groups: the mucoperiosteal denudation group, the mucosal flap excision group, and the periosteum excision group. In the experimental groups, bilateral mucoperiosteal, mucosal flap and periosteum were excised respectively in the lateral one half of the palate. Four rats in each group were randomly chosen for sacrifice every two weeks. The maxilla was dissected following the excision. The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases. At the same time, 12 animals in each group were sequentially injected with calcein every two weeks. Three animals in each group, whose fluorescent labeling was used, were sacrificed for investigating bone formation at Week 8 following injection.</p><p><b>RESULTS</b>(1) Each experimental group presented the constriction of the maxilla and dental arch. The upper first molars in the experimental groups inclined medially. The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group. The indices of the mucosal flap excision group, which retained the structures of the periosteum layer, had the most approximate values to the control group; (2) Different histological changes among the experimental groups were detected. The fibers penetrated into the palatal bone as Sharpey's fibers in the mucoperiosteal denudation group. The pattern of bone deposition was the bundle type. Sharpey's fibers were not found in the mucosal flap and periosteum excision groups and the depositions of palatal bone were the lamellar type as those in the control group; (3) The rates of bone deposition in the experimental groups decreased compared with the control group. The rates in different phases were the most approximate values to those of the control group in the mucosal flap excision group, which has the same structure of periosteum as the control group.</p><p><b>CONCLUSION</b>There were different effects on the growth and development of the maxilla and dental arch in different types of palatal lateral excisions. Periosteum is important for bone formation and deposition pattern. The prevention of Sharpey's fibers forming and attaching to the palatine can effectively avert the following malformation.</p>