【作者】 王晓玲；

【导师】 朱敏；

【作者基本信息】 上海交通大学 ， 口腔临床医学， 2016， 硕士

【摘要】 背景与目的:长期张口呼吸导致下颌骨的生长发育不足已得到众多临床研究的证实,但其具体机制不详。本研究旨在通过幼年大鼠张口呼吸的动物模型来探讨其对下颌骨及髁突的生长发育的影响,以及其对髁突骨髓间充质干细胞成软骨向分化的作用。方法:40只4周龄SD大鼠随机分为两组:双侧鼻阻塞组(张口呼吸组),28只;对照组,12只。鼻阻塞组采用自制的阻塞器阻塞双侧鼻腔,阻塞时间为8:00 a.m.-4:00 p.m.,至8周;对照组不做处理。建模期间每日体重监测,分别取不同生长发育时间段的大鼠进行下颌骨CT扫描重建并测量,取双侧髁突骨髓间充质干细胞体外培养并鉴定,CCK-8法比较两组细胞增殖差异,RT-PCR法检测两组骨髓间充质干细胞成软骨标志基因(Agg、COL-Ⅱ、Sox-9)表达的差异。结果:实验4周后,鼻阻塞组较对照组体重明显下降,CT测量结果显示下颌骨及髁突的生长发育明显减慢。鼻阻塞组的髁突骨髓间充质干细胞在不同生长发育期的细胞增殖、成软骨标志基因的表达较对照组均显著性下降。结论:幼年大鼠双侧间歇性鼻阻塞致其生长发育期张口呼吸,出现下颌骨及髁突的发育不足,可能与髁突骨髓间充质干细胞软骨向分化受抑制有关。更多还原

【Abstract】 Background&Purpose:The fact that long-term mouth breathing would lead to mandibular deficiency has been confirmed by numerous clinical studies.However the specific mechanism still remains unknown.This study aims to utilize the animal model of mouth breathing,to discuss its influence on the growth and development of mandible and condyle,and also its effect on the chondrogenic differentiation of Bone Marrow derived Mesenchymal Stem Cells(BMSCs)derived from condyleMethods:Forty 4-week-old Sprague Dawley(SD)rats were randomly divided into two groups.The experiment group contains 28 rats,referring to the mouth-breathing group,while the control group contains 12 rats The experiment group had both nostrils occluded by nose plugs,from 8:00 a.m.to 4:00 p.m.every day.The control group had no processing The animal experiment lasted for 4 weeks.During modeling daily weight of each rat was monitored,different growth period of the mandibles were scanned by CT and reconstructed.Bilateral condylar BMSCs were cultured in vitro,CCK-8 was used to compare the difference of cell proliferation,RT-PCR was used to detect the difference of gene expression of BMSCs chondrogenic marker genes(Agg,COL-Ⅱ,Sox-9)Results:There was a significant decrease of weight in the obstruction group than the control group after 4 weeks.CT results showed that the mandible and condyle in the experiment group grew much slower than the control ones.During modeling,different growth period of condylar BMSCs cell proliferation ability,as well as the expression of chondrogenic marker genes(Agg,COL-Ⅱ,Sox-9)were all significantly lower in the experiment group than the control group.Conclusion:Long-term mouth breathing caused by bilateral intermittent nasal obstruction,would result in the deficiency of the mandible and condyle of the rats.The mechanism might be closely related to the inhibition of condylar BMSCs cartilage differentiation.更多还原