咬合创伤去除前后牙髓组织中降钙素基因相关肽阳性神经纤维的变化

目的 研究咬合创伤对牙髓组织中降钙素基因相关肽(calcitonin gene-related peptide，CGRP)阳性神经纤维的影响，以及去除咬合创伤后牙髓组织中CGRP阳性纤维的恢复情况。方法 利用免疫组织化学方法，观察咬合创伤去除前后不同时期大鼠实验牙牙髓组织中CGRP阳性神经纤维的变化。结果 咬合创伤期实验牙牙髓组织中CGRP阳性纤维与对照牙相比逐渐出现数量增多、密度增加及纤维增粗的改变，而去除咬合创伤期实验牙牙髓组织中CGRP阳性纤维恢复接近正常大鼠。结论 咬合创伤能够引起大鼠牙髓组织中CGRP阳性纤维出现形态、分布、密度的改变，而去除创伤后大鼠牙髓组织中CGRP阳性纤维恢复接近正常大鼠。     

实验性牙移动牙周膜内降钙素基因相关肽样神经纤维的改变

目的：研究实验性牙移动过程中，牙周膜内降钙素基因相关肽（CGRP）样神经纤维的改变。方法：在大鼠左侧第一、二磨牙间塞入一弹性橡皮圈模拟临床正畸加力状态，对牙周膜内神经进行CGRP免疫组化染色。结果：加力6h后，牙周膜和牙髓内CGRP样神经纤维明显减少；施力3d后表达开始增加，1周时表达最强，2周时趋于恢复正常。结论：实验性牙移动引起牙周膜内CGRP样神经纤维规律性的改变，提示CGRP免疫阳性感觉神经可能参与实验性牙移动中的骨组织改建和局部的炎性反应。     

电子麻醉在牙髓病治疗中的镇痛效果

应用牙髓电活力测试仪观察了电子麻醉对正常牙齿疼痛阈值的影响 ,并评价电子麻醉对开髓术和前牙去髓术的镇痛效果。1　材料和方法1.1　实验仪器ＹＤＭ -Ｉ型牙科电子麻醉仪 (第四军医大学生物医学工程系试制 ) ;牙髓电活力测试仪 (Ｍｏｄｅｌ 80 0 1,ＡｎａｌｙｔｉｃＴｅｃｈ ｎｏｌｏｇｙ ,ＵＳＡ)1.2　方法1.2 .1　实验对象的选择在临床上选择健康自愿者和闭锁性牙髓炎需行开髓术且对疼痛敏感、难以忍受者 ,前牙牙髓炎患者 ,或因修复需要行牙髓治疗的患者。要求年龄在 16岁以上 ,性别和牙位随机。电子麻醉禁用于戴有起搏器、癫痫、心脑血…     

牙髓组织中降钙素基因相关肽和P物质的研究现状

近十年来，国内外学者对牙髓组织中CGRP和SP两种神经肽作了比较深入的研究。本文就降钙素基因相关肽CGRP、P物质（SP）阳性纤维在牙髓组织中的分布、CGRP和SP在牙髓组织中的作用，以及牙髓组织中这两种神经肽的临床意义作了简要综述。指出这两种神经肽在炎症、损伤、咬合创伤等情况下，参与牙髓组织的病理改变。     

咬合创伤对牙周组织中CGRP免疫阳性纤维的影响

目的：探讨咬合创伤对牙周组织中降钙基因相关肽（CGRP）的影响。方法：利用免疫组织化学方法,观察大鼠牙齿在咬合创伤后1天、3天、7天、15天、1个月等不同实验期牙周组织中CGRP免疫阳性纤维的变化。结果：咬合创伤引起大鼠牙周组织中CGRP免疫反应阳性纤维出现形态、分布、密度的改变。结论：咬合创伤可使牙周组织中的神经末梢释放CGRP,CGRP可能参与了创伤所致的的牙周组织的炎症及修复过程。     

P物质、降钙素基因相关肽调节牙髓微循环的机制

刺激牙齿和电刺激下牙槽神经干诱发牙髓血管扩张现象的机制尚不清楚。随着对Ｐ物质 (ＳＰ)、降钙素基因相关肽 (ＣＧＲＰ)在牙髓中的分布、释放特点和药理作用的认识 ,现已明了刺激牙齿和下牙槽神经干后牙髓组织发生的充血性变化与ＳＰ、ＣＧＲＰ有重要联系。1　牙髓ＳＰ、ＣＧＲＰ能感觉神经纤维传出功能的证据感觉神经具有传入功能 ,兴奋后将信息向中枢方向传导。此外感觉神经还有传出功能 ,将兴奋逆传导方向传向外周 ,向外周组织释放神经活性物质 ,在局部组织中发挥生物学效应。牙髓组织中有丰富的ＳＰ、ＣＧＲＰ能感觉神经纤维。大量的…     

咬合创伤牙髓组织中CGRP免疫阳性纤维的变化

目的：探讨胶合创伤对牙髓组织中降钙素基因相关肽（CGRP）的影响。方法：利用免疫组织化学方法，观察大鼠牙齿在咬合创伤后1天、3天、7天、15天、1个月等不同实验期牙髓组织中CGRP免疫阳性纤维的变化。结果：咬合创伤引起大鼠牙髓组织中CGRP免疫反应阳性纤维出现形态、分布、密度的改变。结论：咬合创伤可使牙髓组织中的神经末梢释放CGRP、CGRP可能参与了创伤所致的牙髓炎症及修复过程。     

人前磨牙牙髓牙本质复合体中CGRP阳性神经纤维的研究

目的 :研究CGRP在牙髓牙本质复合体中的表达 ,探讨牙痛、牙过敏机理。方法 :收集人前磨牙 ,石蜡包埋切片 ,免疫组化 ,图象定量分析。结果 :CGRP阳性神经纤维分布于牙髓、前期牙本质 ,但不到达成熟牙本质 ,部分分支围绕血管 ,部分分支终止于牙髓基质 ,或成牙本质细胞层 ,或前期牙本质。CGRP阳性神经纤维在冠髓的积分光密度为 12 .39± 1.6 6 ,体密度为 0 .0 182± 0 .0 10 6 ,线密度为 0 .0 0 46± 0 .0 0 2 6 ,在冠部前期牙本质的积分光密度为13 .0 7± 1.74,线段长度为 (19.42± 8.43)mm。结论 :CGRP阳性神经纤维分布于牙髓、前期牙本质 ,未达成熟牙本质 ,牙外因素引起的牙痛可能与间接刺激神经有关 ,牙内因素引起的牙痛可能与直接刺激神经有关。     

咬合创伤致牙髓血管及CGRP阳性神经的改变

目的:探讨咬合创伤对大鼠牙髓降钙素基因相关肽(CGRP)阳性纤维及牙髓血管的影响,和牙髓神经和血管反应间的关系。方法:HE和免疫组织化学染色方法,观察右下颌第一磨牙咬合创伤大鼠,右下牙槽神经干切断大鼠及空白对照大鼠的右下颌第一磨牙牙髓血管形态、CGRP阳性纤维末梢的形态变化。分析比较二者间的关系。结果:咬合创伤3-30天组,牙髓血管扩张程度和例数进行性增加。无细胞区CGRP-阳性纤维密度逐渐增加。相邻切片对比后显示扩张的血管和毛细血管的相应位置,CGRP-免疫阳性表达增强。牙髓炎症区内炎细胞浸润和血管扩张渗出处,CGRP-免疫阳性结构明显增多、表达增强。60-90天组,牙髓变性坏死例数增多,使牙髓血管扩张例数相对减少,扩张区域伴有CGRP-免疫阳性表达增强。咬合创伤并切断下牙槽神经干组,可见无细胞区有少量CGRP免疫阳性物质,呈淡染的颗粒状,短丝状。血管扩张不明显。1例标本牙髓血管明显扩张,相应区域CGRP阳性纤维束呈浓密的树枝状。结论:咬合创伤引起神经形态的改变及神经源性炎症,神经纤维和牙髓血管在分布上和变化上有一致性。     

实验性牙髓炎大鼠三叉神经系统CGRP的动态表达

目的:观察牙髓炎大鼠三叉神经节及牙髓中CGRP的分布,探讨神经系统参与牙髓病理改变的信号调节作用。方法:建立完全弗氏佐剂诱发的大鼠牙髓炎及痛敏模型,应用免疫组化法标记CGRP的表达变化。结果:炎症刺激后,初级感觉神经元及其轴突的CGRP表达明显增强,1周后显著性减少。而牙髓CGRP阳性传出神经纤维在牙髓炎症刺激后显著减少,1周后呈回升趋势。结论:三叉神经系统通过调节CGRP的表达参与牙髓的炎症及痛觉过敏过程。     

The distribution and origin of substance P-like immunoreactivity in the rat molar pulp and periodontal tissues

Rat mandibles were fixed in Zamboni fixative and demineralized in a mixture of EDTA and fixative. Substance P-like immunoreactivity was demonstrated by indirect immunofluorescence in molar pulp, periodontal ligament and gingiva. Substance P (SP) containing nerve fibres with varicosities were observed in the pulp horn and root pulp in general located around blood vessels. Some SP-containing fibres penetrated into the predentine and dentine. In the periodontal ligament, SP fibres were localized along the blood vessels in the middle and apical regions. Many SP-containing fibres were associated with the blood vessels in the lamina propria of gingiva. After inferior alveolar nerve section, SP-positive nerve fibres in the pulp and periodontal ligament disappeared completely. In gingiva the number of SP fibres decreased but not all fibres disappeared. Removal of the superior cervical ganglion did not affect the distribution of SP-containing nerve fibres.     

牙髓损伤性刺激诱导大鼠三叉神经脊束尾侧亚核内P物质等多肽的表达

目的：比较、分析急性牙髓炎和牙齿开髓刺激后,三叉神经脊束核尾侧亚核（Ｖｃ）内Ｐ物质（ＳＰ）、降钙素基因相关肽（ＣＧＲＰ）的变化。方法：利用免疫组织化学染色方法观察大鼠牙齿开髓后１ｈ、２ｈ、４ｈ和急性牙髓炎２ｈ、４ｈ组Ｖｃ内ＳＰ、ＣＧＲＰ免疫阳性纤维的变化。结果：开髓１ｈ组实验侧与对照侧相比,ＳＰ、ＣＧＲＰ免疫阳性纤维减少,其余各组的实验侧与对照侧无显著差异。结论：两种刺激均引起Ｖｃ内三叉神经末梢释放ＳＰ、ＣＧＲＰ。     

Nerve fibers immunoreactive to calcitonin gene-related peptide,substance P,neuropeptide Y,and dopamine ß-hydroxylase in innervated and denervated oral tissues in ferrets

The effect of sensory and sympathetic denervation on the localization and distribution of nerve fibers immunoreactive (IR) to calcitonin gene-related peptide (CGRP), substance P (SP), neuropeptide Y (NPY), and dopamine β-hydroxylase (DBH) was studied in the dental pulp, periodontal ligament (PDL), and gingiva in ferrets. Unilateral axotomy was performed by resection of the inferior alveolar nerve (IAN) 10 days before the experiment (Group 1); sympathectomy, by unilateral removal of the cervical ganglion 5 days before the experiments (Group 2). Immunohistochemistry was performed on free-floating sections by the avidin±biotin±peroxidase technique. A considerably higher density of sensory fibers IR to CGRP and SP was found in the dental pulp than in PDL and gingiva. The majority of pulpal fibers were located in the walls of blood vessels. A subodontoblastic network of fibers IR to CGRP and SP was lacking in incisors and canines and was found only in the coronal pulp in premolars and molars. Sympathetic fibers were sparsely distributed in the pulp, and they were mainly confined to large vessels running centrally in the root pulp as well as the larger vessels in apical PDL and alveolar bone. Gingiva was well supplied with CGRP- and SPIR nerves, and some NPY and DBH fibers were located in association with larger vessels. Round cell-like structures within the basal part of the epithelium were CGRP-IR. Axotomy induced a complete loss of CGRP- and SP-IR fibers in the anterior part of the jaws, whereas sympathectomy caused a reduction, but not a total loss, of NPY- and DBH-IR nerves. It is concluded that, except for some distributional differences, the oral tissues in the ferret have an abundant sensory innervation similar to that found in other species.     

Neurogenic inflammation and the oral mucosa

Abstract. Since the rôle of neurogenic inflammation in various pathological conditions is well-established, we presume that it also has great importance in the development of several inflammatory processes in the oral mucosa. In the course of experimentally-induced neurogenic inflammation of the oral mucosa in rats, vasodilation and plasma extravasation occur in the area supplied by unmyelinated capsaicin-sensitive fibres. Upon activating these fibres in the oral mucosa, mediators such as histamine, substance P (SP) and calcitonin gene related peptide (CGRP) are released from the peripheral terminals of afferent nerves causing characteristic symptoms of neurogenic inflammation. By histochemical techniques, SP- and CGRP-immunoreactive fibres have occurred in the area of the rat oral mucosa stimulated mostly in the free and attached gingiva around the molar teeth in the lower jaw. Capsaicin pretreatment performed neonatally or at adult age causes a loss of SP-immunoreactive fibres and prevents the vaso-dilatory responses, as well as the increase in vascular permeability elicited by the antidromic stimulation of the inferior alveolar nerve. As the transection of inferior alveolar nerve decreased the extravasation of Evans blue on the ipsilateal side and did not affect the capsaicin-induced enhancement in blood flow, we suggest that the two symptoms of the inflammation, i.e., the increased vascular permeability and decreased vascular resistance, should be produced by different mechanisms. The results of all the morphological and functional studies seem to confirm the possibility that there is an important neurogenic component of the inflammatory alterations caused by different mechanical and chemical stimuli in the oral mucosa.     

大鼠磨牙及牙周组织中神经纤维分布:神经丝蛋白免疫组织化学研究

目的：观察大鼠磨牙及牙周组织神经纤维分布特点。方法：大鼠磨牙及其牙槽骨脱钙后切征并行神经丝蛋白（ＮＦＰ）免疫,组织化学染色。结果：大鼠磨牙、牙周膜及牙龈中神经纤维丰富,神经丝蛋白阳性神经纤维在髓角处形成牙本质细胞下丛,其中一些神经纤维进入牙本质。在牙周膜,神经丝蛋白阳性神经纤维在牙根下段密集分布 。因牙周膜内存在两型神经来梢：游离神经来梢及Ｒｕｆｆｉｎｉ终末。前者在整个牙周膜内皆有分布。后者常成组     

Regeneration of calcitonin gene-related peptide immunoreactive nerves in replanted rat molars and their supporting tissues.

First maxillary right molars in 66 rats were elevated and replanted and the pulps allowed to regenerate for 1-90 days. The contralateral tooth served as control. Regeneration of nerves in the pulp and periodontium was studied by CGRP-immunohistochemistry and the avidin-biotin-peroxidase method. The pulp and periodontium of the controls were richly supplied with CGRP-labelled nerves. One day after replantation the pulp was completely devoid of CGRP-immunoreactive nerves. After 2 days, axon sprouts were present in the apical, regenerated pulp and in the periodontium. From 3-7 days CGRP-immunoreactive axons were regularly seen to have regenerated in front of the cellular inflammation in the pulp. After 10 days, the pulps were reinnervated up to the horns, although more sparsely than in the controls. From day 20-90 there was a marked divergence in pulpal healing: 17 pulps formed irregular postoperative dentine with a gradual increase in nerve density; 16 pulps remained sparsely innervated and were gradually replaced by bone. Root resorption was most extensive in the teeth with bone replacement of pulp. The soft tissue adjacent to extensive resorbing areas had many more CGRP-labelled axons than in the controls. The reinnervation of the regenerating pulp occurred at the same time as pulpal wound healing, but did not achieve the innervation density of the controls.     

Calcitonin gene related peptide: a sensory transmitter in dental pulps?

Nerve fibers displaying calcitonin gene related peptide (CGRP) immunoreactivity occurred in dental pulps of several mammals, including man. The CGRP fibers were more numerous in the apical parts than in the coronal parts and were distributed around small blood vessels as well as in the pulpal stroma without any obvious relation to blood vessels. The trigeminal, spinal and jugular-nodose ganglia harbored a moderate supply of CGRP immunoreactive perikarya and nerve fibers. Immunocytochemic double staining revealed the coexistence of CGRP and SP in a population of perikarya in the sensory ganglia and suggested coexistence of the two peptides in perivascular nerve fibers in the cat dental pulp. The cervical sympathetic ganglia did not contain CGRP-immunoreactive perikarya. Cervical sympathectomy (studied in the guinea-pig and rat) did not affect the frequency or distribution of pulpal CGRP fibers. The distribution of CGRP fibers within the dental pulp and the presence of CGRP perikarya in sensory ganglia known to supply the dental pulps indicate that the pulpal CGRP fibers are sensory in nature and that CGRP together with SP may participate in the regulation of local blood flow and the response to local inflammation.     

Neural Regeneration/Remodeling in Engineered Coronal Pulp Tissue in the Rat Molar

IntroductionThis study aimed to examine the process of reinnervation during coronal pulp tissue regeneration in a rat model in which rat bone marrow mesenchymal stem cells were implanted in pulpotomized molars.MethodsThe maxillary first molars of Wistar rats were pulpotomized, and preformed biodegradable porous poly L-lactic acid scaffolds and hydrogel carrying rat bone marrow mesenchymal stem cells were implanted in the pulp chamber. After 3, 7, and 14 days, the implanted teeth were processed for histologic analysis; immunoperoxidase staining for protein gene product 9.5 (a general neuronal marker), calcitonin gene-related peptide (CGRP), or substance P (SP); and real-time polymerase chain reaction for nerve growth factor (NGF) and growth-associated protein 43 (GAP-43) messenger RNA (mRNA) expression.ResultsHistologic analysis of the implanted region revealed sparse cellular distribution at 3 days, pulplike tissue with a thin dentin bridge–like structure at 7 days, and dentin bridge–like mineralized tissue formation and resorption of most scaffolds at 14 days. Protein gene product 9.5 and CGRP-immunoreactive nerve fibers showed the lowest density at 3 days and significantly increased until 14 days when the CGRP-immunoreactive fibers reached normal levels. SP-immunoreactive nerve fibers showed the highest density at 7 days and decreased to normal levels at 14 days. NGF mRNA increased with time, whereas GAP-43 mRNA levels peaked at 3 days and subsequently dropped until 14 days.ConclusionsRegeneration/remodeling of SP-immunoreactive and CGRP-immunoreactive nerve fibers with increased mRNA expression of NGF and GAP-43 occurred in a rat model of coronal pulp tissue engineering with bone marrow mesenchymal stem cells.