咬合重建对大鼠颞颌关节P物质表达影响的研究

Expressions of substance P in rat TMJ during occlusal reconstruction for unilateral chew

目的研究咬合重建对大鼠颞颌关节P物质(substance P,SP)表达的影响。方法Wistar雄性大鼠30只,随机分为3个实验组及相应的正常对照组,每组5只。实验组动物间断磨除右上、下颌磨牙牙冠至龈下,有二组分别第3周、第9周停止磨牙,任其自行萌出,恢复咬合关系。切片行SP免疫组织化学反应(SABC法)及HE染色。光镜观察拍片,并用Image Pro Plus5.1图像分析软件分别进行测定。结果与对照组对照。SPSS10.0软件行统计分析。结果单侧咀嚼实验组咀嚼侧和非咀嚼侧颞颌关节单位面积内SP阳性纤维面积与对照组比较显著增加(P<0.01,P<0.05),其非咀嚼侧单位面积内SP阳性纤维面积明显高于咀嚼侧(P<0.01)。早期恢复咬合实验组SP阳性纤维面积与对照组比较无差别(P>0.05),其咀嚼侧与非咀嚼侧比较无差别(P>0.05)。晚期恢复咬合实验组SP阳性纤维面积与对照组比较显著增加(P<0.01,P<0.05),其非咀嚼侧单位面积内SP阳性纤维面积明显高于咀嚼侧(P<0.05)。早期恢复咬合实验组HE切片关节结构基本正常,晚期恢复咬合实验组HE切片关节结构有受损病理变化。结论早期恢复咬合关系颞颌关节内损伤及SP表达可恢复正常,晚期恢复咬合关系关节内损伤及SP表达不能恢复正常,SP参与了单侧咀嚼引起的颞颌关节病的病理变化过程。

Objective To investigate the expressions of substance P （SP） in rat TMJ during occlusal reconstruction for unilateral chew, and to discuss the significance of the change of SP expression relevant for temporomandibular disorders. Methods Thirty Wistar male rats were randomly divided into 3 experimental groups and 3 control groups,5 rats in each group. The molar of right maxillary and mandibular in experimental groups were ground to the gingival level without occlusal contact. The occlusal contact was recovered by stoping grounding molar of the rats. The sections of disc and articular capsule were immunohistostained for SP by using SABC method. The sections of disc and condylar process were also stained for HE. Light microscope and microscoic photo analytic software and SPSS10. 0 statistical software were used. Results The areas of substance P - like immunoreactive （ SP - LI） nerve fibers in unilateral chew experimental group were obviously larger than those in control group （ P 〈0.01, P 〈 0.05 ）. The increased extent in non- chewing side was much higher than that in the chewing side （ P 〈0.05 ）. There was no significant difference in the areas of SP - LI nerve fibers between the early occlusal reconstruction experiment group and the control group （ P 〉 0.05 ） and there was also no significant difference between the non - chewing side and the chewing side （ P 〉 0.05 ）. There was a significant difference in the areas of SP - LI nerve fibers between the later occlusal reconstruction experiment group and the control group （ P 〈 0.01, P 〈 0.05 ） and the non - chewing side and the chewing side （ P 〈 0.05 ）. The TMJ of early occlusal reconstruction experiment group were showed normal. There were some pathognostic changes in TMJ in later occlusal reconstruction experiment group. Conclusion The expressions of SP can recover to normal level in the early occlusal reconstruction, but not in the later occlusal reconstruction. SP might participate in the histopathologic mechanism of temporomandibular disorders. Early occlusal reconstruction may be important for prevention of development of temporomandibular disorders.