锂盐对大鼠腭中缝扩张成骨的影响

目的：观察锂盐对腭中缝扩张后新骨形成的影响。方法：使用扩大簧对Wistar大鼠作快速扩弓,腭中缝扩大3d后每日给予LiCl灌胃,对照组使用NaCl。通过甲苯胺蓝染色定量分析新骨的形成,免疫组化染色检测β-catenin的表达。结果：腭中缝扩大后第3天开始有新骨形成,应用LiCl后新骨边缘成骨细胞表达β-catenin增加。半定量分析显示实验组7d新骨形成量显著增加,是对照组的1.36倍（P〈0.05）。结论：锂盐能够通过激活β-catenin信号,促进大鼠腭中缝扩大后的新骨形成。     

局部应用芦荟膏对大鼠拔牙窝早期愈合的影响

目的 研究拔牙窝内填塞芦荟膏对牙槽窝骨愈合的影响,为临床应用提供实验依据.方法 采用20只Wister大鼠,拔除左右上颌第一磨牙,建立拔牙窝动物模型.右侧拔牙窝中放入300g/L的芦荟膏作为实验组,左侧拔牙窝不放置任何药品作为对照组,观察拔牙窝愈合情况.于拔牙后第4、8、15、30、60d分5批处死大鼠,制取拔牙创标本,并行X线检查和扫描电镜观察.结果 X线检查结果显示实验组拔牙窝愈合较快,新骨形成速度及骨密度明显优于对照组.扫描电镜显示实验组拔牙窝愈合速度明显优于对照组,术后30d时,实验组拔牙窝基本愈合,对照组仍可见明显的骨吸收陷窝,直至60d时拔牙窝基本愈合.结论 芦荟膏对大鼠拔牙窝的早期愈合具有促进作用.     

贝复济（bFGF）促进拔牙创早期愈合的动物实验研究

目的：探讨碱性成纤维细胞生长因子（bFGF)在拔牙创早期愈合过程中的作用。方法：采用8只家犬拔牙创动物模型,拔牙后前5天,在一侧拔牙创局部喷涂贝复济,为实验组,每日三次（每次约含bFGF 300AU),另一侧不作处理为对照组。拔牙后0,5,7,10天测量创口面积,第7天和14天各处死一组动物作组织学观察。结果：实验组拔牙后早期的创口面积与对照组之间存在显著性差异（P＜0．05）,组织学观察其创口内新骨形成数目比对照组多,成骨速度较对照组快。结论：贝复济（bFGF)具有显著促进拔牙创成纤维细胞增殖及肉芽组织和上皮细胞生长,有利于牙槽新骨形成的作用,从而有效地促进了拔牙创的早期愈合。     

锂盐促进大鼠前腭缝扩张成骨中血管形成的研究

目的：观察锂盐对大鼠前腭缝扩张后血管形成的影响。方法：扩大簧扩张SD大鼠前腭缝,实验组于扩张前7d开始每天注射氯化锂,对照组注射氯化钠,扩张后2、5、7d处死。免疫组化检测β-catenin表达,CD31、vWF抗体检测血管形成,钙黄绿素标记新骨形成。结果：β-catenin在成骨细胞和血管内皮细胞中表达,实验组β—catenin信号增强,同时血管形成显著增多,7d后新骨量明显增加。提示通过增强β-catenin信号促进血管形成,是锂盐促进大鼠前腭缝牵张成骨的途径之一。     

唑来膦酸对大鼠颌面骨和外周骨创伤后骨改建的影响

目的 研究唑来膦酸对大鼠颌面骨和外周骨创伤后骨改建的影响。方法 SD大鼠随机分为实验组和对照组,每周分别给予尾静脉注射唑来膦酸(80μg/kg)和PBS。用药两周后,在全麻下拔除一侧上颌第一磨牙,并在同侧胫骨近心端制备骨缺损,缝合创口,继续用药至术后1、4和12周后分批处死,分离并收集骨组织样本。Micro-CT分析各组骨缺损区新骨形成情况。HE和Masson染色分析骨缺损区软组织愈合情况、新骨形成情况、有无炎症反应和死骨形成等。ELISA法检测骨改建过程中关键因子RANKL和OPG的表达。结果 Micro-CT结果显示,实验组拔牙创表面高低不平,中部浅凹处可见游离的死骨片,而对照组拔牙创新骨形成区域与周边骨质均匀连续,进行了正常的生理性骨改建。实验组胫骨缺损区愈合,骨皮质完整连续,较对照组厚且致密,骨松质内的新生骨亦明显较对照组排列紧密。术后4周和12周,实验组胫骨BV/TV值较对照组明显上升(P<0.05),实验组颌骨BV/TV值较对照组差异无统计学意义。组织学染色显示,实验组颌骨拔牙创黏膜未愈合或延迟愈合,未愈合的黏膜下方可见暴露骨坏死,骨质出现不同程度的硬化,且周围伴有大...     

芦荟膏对拔牙创组织愈合的动物实验

目的: 探讨芦荟膏对拔牙创早期愈合的促进作用.方法:采用60只Wister大鼠建立拔牙创动物模型.选每只右侧上颌磨牙拔牙创为实验组,将300 s/L的芦荟膏放入拔牙创内;左侧同名牙的拔牙创为对照组,拔牙后按常规处理创面.通过肉眼观察软组织的愈合情况、测量创口面积和组织学观察.结果:组织学观察结果显示实验组愈合明显优于对照组,创口面积差异有统计学意义,实验组的拔牙创愈合比对照组平均提前15～20 d.结论:芦荟膏具有明显的促进拔牙创组织愈合的作用.     

局部应用β-catenin增强剂促进大鼠前腭缝扩张成骨

目的：Wnt/β-catenin信号通路在成骨细胞的发生及骨形成过程中起着重要调控作用,该研究观察大鼠前腭缝扩张后局部应用β-catenin增强剂对成骨细胞增殖分化和新骨形成的影响。方法：取40只雄性SD大鼠,随机分为扩张组和未扩张组,扩张组大鼠上颌切牙安放扩大簧扩张前腭缝,2组动物均于实验当天或第2天开始在前腭缝注射β-catenin增强剂（SB-415286）或赋形剂,每天1次,共2次,分别于第2天和第4天后处死。BrdU缓释凝胶标记增殖细胞并观察其向成骨细胞的分化,HE染色观察新骨生成。应用Image-ProPlus生物图像分析系统对增殖细胞数及新骨量作半定量分析,SPSS16.0软件包对数据进行统计学分析。结果：注射增强剂对未扩张的前腭缝无影响。扩张后2d,细胞增殖明显,注射增强剂组骨缝边缘BrdU阳性增殖细胞显著多于赋形剂组。扩张后4d有新骨形成,部分BrdU阳性细胞包埋于新骨基质中。注射增强剂后,新骨中BrdU阳性细胞明显增多,其中0d注射组多于2d注射组（P〈0.01）。同时,注射增强剂后新骨量显著增加,0d注射组增加30%（P〈0.01）,2d注射组增加20%（P〈0.05）。结论：大鼠前腭缝扩张后局部应用β-catenin增强剂,促进了成骨细胞的增殖和分化,从而促进新骨的形成。     

胰岛素样生长因子I对高糖条件下成骨细胞骨形成的影响

目的:研究胰岛素样生长因子I对高糖条件下成骨细胞骨形成的影响,探讨胰岛素样生长因子I对糖尿病性骨病的作用机制.方法:离体实验通过对细胞增殖和矿化的检测,从细胞分子水平评价胰岛素样生长因子I对高糖环境下成骨细胞的作用.体内实验诱导1型糖尿病大鼠动物模型,分别给予胰岛素(6～8 U/d)和胰岛素样生长因子I(30 μg/kg·d)治疗,通过X线、组织切片HE染色和四环素双标记的方法观察牙槽骨改建情况.结果:离体实验的结果显示胰岛素样生长因子I可减少高浓度葡萄糖引起的成骨细胞的异常增殖,促进钙沉积和矿化结节的形成.体内实验研究显示与正常组相比,糖尿病大鼠拔牙创骨愈合减慢,骨形成减少,牙槽骨高度和牙槽骨骨形成率显著降低.胰岛素样生长因子I的治疗不仅能控制糖尿病大鼠的血糖保持在正常范围内,还可以增加牙槽骨高度和提高骨形成率.结论:高浓度葡萄糖导致糖尿病大鼠拔牙后骨形成减少、牙槽骨高度降低等病理改变;胰岛素样生长因子I可以促进糖尿病状态下成骨细胞骨形成和矿化,有利于糖尿病大鼠拔牙后骨创愈合和新骨形成.     

应用缓释BrdU检测前腭缝成骨细胞的增殖活性

目的:配制缓释BrdU,用于检测前腭缝牵张成骨过程中成骨细胞的增殖和分化,探讨前腭缝牵张成骨的机制。方法:用泊洛沙姆温敏凝胶配制缓释BrdU,大鼠皮下注射后不同时间点采取血样,高效液相色谱法测定BrdU血药浓度,并与腹腔注射BrdU溶液进行比较。选取35天龄雄性SD大鼠40只,随机分为实验组和对照组,实验组安放扩大簧牵张前腭缝。2组动物于24h后随机皮下注射BrdU温敏凝胶1次或腹腔注射BrdU溶液1次。所有动物分别于48h和96h处死(n=5),免疫组化染色检测细胞的增殖和迁移。结果:皮下注射BrdU温敏凝胶6h后,血清中仍可检测出1.21μg/mL BrdU,免疫组化染色可见大鼠前腭缝有BrdU阳性的增殖细胞。腹腔注射BrdU溶液3h后,血清中仅检测到0.17μg/mL BrdU,免疫组化染色未见BrdU阳性细胞。前腭缝牵张48h后,骨缝边缘可见大量BrdU阳性成骨细胞;96h后可见部分BrdU阳性细胞包埋于骨缝边缘的新生骨基质中。结论:BrdU温敏凝胶能起到良好的缓释效果,为体内标记成骨细胞提供了一种简便易行的方法。牵张力作用于前腭缝后,促进骨缝边缘的间充质细胞增殖,这些细胞分化为成骨细胞并分泌骨基质,从而促进新骨形成。     

光动力疗法对牙周炎磨牙拔牙窝愈合影响的随机对照优效性临床试验

目的评估光动力疗法(PDT)对牙周炎磨牙拔牙窝软组织愈合、拔牙后疼痛度、影像学骨密度和骨高度改变的影响。方法本研究为一项单中心单盲随机对照优效性临床试验, 共纳入2022年12月至2023年9月在浙江大学医学院附属口腔医院牙周科就诊患者需要拔除的38个牙周炎磨牙位点, 按照简单随机方法分为PDT组和对照组, 每组19个位点, PDT组拔牙后常规清创并辅助使用PDT, 对照组拔牙后仅常规清创。在拔牙后即刻、7 d、14 d分别测定两组拔牙窝颊舌径及近远中径并计算7和14 d创面愈合率, 在拔牙后7和14 d评估两组拔牙窝软组织愈合指数, 使用视觉模拟评分法评估两组拔牙后6 h和1、2、3 d时的疼痛度, 在拔牙后即刻和2个月拍摄根尖片比较两组拔牙窝骨密度及骨高度的变化, 并进行统计学分析。结果拔牙后7 d创面愈合率PDT组[(78.08±5.45)%]显著高于对照组[(71.03±6.82)%](P<0.01), 拔牙后14 d创面愈合率PDT组[(85.88±3.84)%]亦显著高于对照组[(81.66±3.79)%](P<0.01), 但均未达到优效性检验的优效界值(优效...     

Effects of lithium on extraction socket healing in rats assessed with micro-computed tomography

Abstract

Objective. Lithium is an activator of β-catenin signaling and β-catenin plays an important role in regulating bone formation and remodeling. The purpose of this study was to investigate the effects of lithium on bone repair in tooth extraction sockets in rats. Material and methods. Twenty male Wistar rats were subjected to maxillary left second molar extraction. The animals received a daily injection of lithium chloride (LiCl) or the same dose of sodium chloride (NaCl) starting 7 days before tooth extraction until sacrifice 14 days after extraction. Rats were randomly divided into: (1) a pre-treated group that received LiCl injection from 7 days before to 3 days after tooth extraction; (2) a post-treated group that received LiCl injection starting 4 days after tooth extraction; (3) a continuously treated group that received LiCl injection for the entire 21 days; and (4) a control group that received NaCl injection only. The volume of new bone and the bone density in the extraction socket were quantified by micro-computed tomography. Results. The percentage of new bone formation in the extraction socket was as follows: 63.2 ± 13.4% (pre-treated group), 53.9 ± 9.8% (post-treated), 23.8 ± 8.0% (continuously treated) and 37.5 ± 4.2% (control). The difference in percentage was statistically significant between each pair of groups. Pre- and post-treated groups also showed a significant increase in the density of new bone. Conclusions. Lithium enhances bone repair in extraction sockets when delivered before or after tooth extraction. Tooth extraction during lithium treatment may impair bone healing.     

Connective tissue growth factor expressed in rat alveolar bone regeneration sites after tooth extraction

OBJECTIVE: To understand bone regeneration process after tooth extraction could be a clue to develop a new strategy for alveolar bone reconstruction. Recently, accumulated evidences support that connective tissue growth factor (CTGF) is implicated in tissue repair of many tissues. In this study, we investigated the spatial and temporal expression of CTGF in the rat tooth extraction sockets. DESIGN: Five weeks old wild type male rats (weighing 120 g) were used for this experiment. Expression of CTGF was determined by immunohistochemistry and in situ hybridization in the rat upper molar tooth extraction sockets at 2, 4, 7, 10 and 14 days after tooth extraction. RESULTS: CTGF was expressed strongly in the endothelial cells migrating into the granulation tissue at the bottom of the sockets during 4 days after tooth extraction. During the reparative process, no apparent chondrocyte-like cell appeared in the sockets, while osteoblast-like cells proliferated in the sockets with low CTGF expression at 7, 10, 14 days after extraction. As expected, no staining was observed with the preimmune rabbit IgG and CTGF sense probe. CTGF may play an important role in angiogenesis and granulation tissue formation specifically at early healing stage after tooth extraction to initiate alveolar bone repair. CONCLUSION: CTGF was expressed at early healing stage of the rat tooth extraction wound.     

聚乳酸-羟基乙酸-辛伐他汀对拔牙术后剩余牙槽嵴吸收影响的实验研究

目的探讨聚乳酸-羟基乙酸(PLGA)复合辛伐他汀对剩余牙槽嵴吸收的预防作用。方法选用60只Wistar雄性大鼠,随机分为实验组和对照组各30只,拔除右下中切牙后,实验组即刻植入PLGA-辛伐他汀支架材料,对照组植入PLGA支架材料。术后7、14、28、56、84d分别处死实验组和对照组大鼠各6只,用软X线、骨密度、测量组织学等方法进行药效评价。结果剩余牙槽嵴相对长度:术后14、28、56、84d对照组比实验组[(0·997±0·007)、(0·965±0·139)、(0·996±0·021)、(0·960±0·026)]明显降低,差异有统计学意义(P<0·05)。牙槽骨骨密度:术后28、56、84d实验组[(7·101±0·025)、(7·178±0·039)、(7·162±0·052)g/cm2]与对照组[(7·074±0·014)、(7·117±0·012)、(7·059±0·037)g/cm2]相比明显升高,差异有统计学意义(P<0·05)。组织学观察显示实验组成骨速度和质量优于对照组。结论以PLGA为载体局部应用辛伐他汀可诱导拔牙窝内骨形成,保存了剩余牙槽嵴的长度和骨量。     

Sodium hyaluronate accelerates the healing process in tooth sockets of rats

Objective

In this study we evaluated the effects of sodium hyaluronate (HY) in the healing process of tooth sockets of rats.

Design

Immediately after the extraction of the upper first molars of male Holtzman rats, right sockets were treated with 1% HY gel (∼0.1 ml), while left sockets were used as control (blood clot). The animals were sacrificed at 2, 7, and 21 days after tooth extraction and upper maxillaries processed for histological and morphometric analysis of the apical and medium thirds of the sockets. Carbopol, an inert gel, was used to evaluate the mechanical effect of gel injection into sockets. Expression of bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) was determined by immunohistochemistry at 1, 2, 3, 4, 5, and 7 days after tooth extraction.

Results

Histological analysis showed that HY treatment induced earlier trabecular bone deposition resulting in a bone matrix more organized at 7 and 21 days after tooth extraction. Also, HY elicited significant increase in the amount of bone trabeculaes at 7 and 21 days after tooth extraction (percentage of trabecular bone area at 7 days: 13.21 ± 4.66% vs. 2.58 ± 1.36% in the apical third of control sockets) and in the vessels counting at 7 days. Conversely, the number of cell nuclei was decreased in HY-treated sockets. Additionally, expression of BMP-2 and OPN was enhanced in HY-treated sockets compared with control sockets.

Conclusions

These findings suggest that HY accelerates the healing process in tooth sockets of rats stimulating the expression of osteogenic proteins.     

局部应用辛伐他汀对拔牙窝内VEGFmRNA表达的影响及意义

目的：探讨局部应用辛伐他汀促进拔牙术后牙槽骨修复机制。方法：选用健康雄性Wistar大鼠56只,随机分为实验组28只和对照组28只,拔除右下颌中切牙后,实验组即刻植入载辛伐他汀PLGA支架材料,对照组植入单纯PLGA作为对照,于术后5d、1周、2周和4周分别处死大鼠,设计针对VEGFmRNA的寡核苷酸探针,采用原位杂交技术检测拔牙窝VEGFmRNA的表达。结果：术后1周和2周实验组VEGF阳性细胞数和染色强度均高于对照组,且差异有统计学意义,而术后4周,实验组和对照组阳性细胞数无统计学差异,且阳性表达细胞少于术后2周。结论：局部应用辛伐他汀通过增加VEGFmRNA的表达促进拔牙窝骨损伤的愈合。     

成骨诱导剂对拔牙创愈合的影响

目的 探讨以明胶海绵为载体,地塞米松、维生素C和β-甘油磷酸钠组成的成骨诱导剂对拔牙创愈合和牙槽嵴形态改建的影响。方法选用50只家兔,拔除双侧上颌第一前磨牙,右侧拔牙创内填入载有成骨诱导剂的明胶海绵,作为实验侧;左侧填入空载明胶海绵,作为对照侧。拔牙后第1、2、4、8、12周各处死10只动物,取双侧牙槽骨标本,拍摄X线片,并测量骨缺损区新骨密度;用组织学方法评价拔牙创愈合情况;并于12周时,测量拔牙区牙槽嵴高度吸收值。结果X线片骨密度测量显示：术后2、4、8、12周,实验侧骨密度值均高于对照侧,差异有统计学意义（P<0.01）。组织学检查显示：实验侧拔牙创内成骨现象较对照侧早,成骨细胞分化和增殖更活跃。
12周时实验侧牙槽嵴高度吸收值小于对照侧,差异有统计学意义（P<0.01）。结论 由地塞米松、β-甘油磷酸钠和维生素C组成的成骨诱导剂能促进拔牙创愈合,加速成骨和骨改建。     

Comparing the effects of chlorhexidine and persica on alveolar bone healing following tooth extraction in rats, a randomised controlled trial

Chlorhexidine is broadly prescribed by clinicians for treating extraction socket wounds; however, studies have reported adverse effects for chlorhexidine. Persica, a herbal antibacterial agent, could be an alternative for chlorhexidine. The aim of this randomised controlled trial was to investigate the effects of persica and chlorhexidine on alveolar bone healing following tooth extraction in rats. Eighteen Wistar rats were randomly allocated to three study groups: 0.2% chlorhexidine, 10% persica and controls (tap water). The rats were mouth-rinsed for 14 days. On day 8, the mandibular right first molars of all the rats were extracted. On day 21, the rats were euthanized and histological slides of their extraction sockets were prepared. The amount of new bone formation and the number of inflammatory cells in the extraction socket for each rat were recorded. Data were analysed using linear regression and Mann–Whitney tests. There was no significant difference between the control group and the intervention groups in terms of new bone formation and inflammatory cell count. The mean new bone formation was significantly higher in the persica group than in the chlorhexidine group. There was a significant association between new bone formation and inflammatory cell count in the entire sample. In conclusion, there were no significant differences between rinsing with tap water and rinsing with 0.2% chlorhexidine and 10% persica in enhancing extraction socket wound healing in rats. Extraction socket wound healing in rats was better enhanced with 10% persica than 0.2% chlorhexidine.     

炎症对大鼠牙槽骨骨重建的影响

目的：了解拔牙窝残存炎性组织对拔牙后骨重建过程的影响。方法：健康成年SD大鼠56只,6只用于牙齿折裂炎症感染模型建立的预实验,X线片及病理确定8周为根周存在囊肿或肉芽肿炎症感染的时间点。50只大鼠建立下颌左右第一磨牙根周感染模型,8周后根据X线根尖片取36只根尖部炎症明显的大鼠,根据自身对照原则,左侧实验组牙齿拔除后不刮治,右侧对照组刮除感染组织。术后4周、8周、12周分别进行游标卡尺测量、X线影像学检查和组织学检查,评价拔牙后左右侧牙槽骨骨重建是否有差异。结果：术后4周、8周、12周两组牙槽嵴颊舌侧高度差存在差异,实验组颊舌侧高度差值较大,术后4周、8周实验组新骨形成明显少于对照组。结论：炎症组织使拔牙后颊侧牙槽嵴高度明显下降,拔牙窝的前期修复速度减慢。     

Demineralised human dentine matrix stimulates the expression of VEGF and accelerates the bone repair in tooth sockets of rats

ObjectiveIn this study we investigated the possible use of human demineralised dentine matrix (DHDM), obtained from the extracted teeth, as bone graft material and evaluated the expression of vascular endothelial growth factor (VEGF) induced by this material in the healing process of tooth sockets of rats.DesignTo evaluate bone regeneration and expression of VEGF induced by DHDM, thirty-two male Wistar rats weighing approximately 200 g were used. After maxillary second molar extraction, the left sockets were filled with DHDM and the right sockets were naturally filled by blood clot (control). The animals were sacrificed at 3, 7, 14 and 21 days after surgery and upper maxillaries were processed for histological, morphometric and immunohistochemical analyses. DHDM was used to evaluate the mechanical effect of bone graft material into sockets. Expression of VEGF was determined by immunohistochemistry in all groups.ResultsOur results demonstrated a significant increase in the newly formed bone tissue in sockets of 7, 14 and 21 days and a significant increase in VEGF expression at days 7 and 14 on treated sockets.ConclusionsOur results showed that DHDM increases the expression of VEGF and accelerates the healing process in rats tooth sockets, by stimulating bone deposition and also vessels formation. These results suggest that DHDM has osteoinductive/osteoconductive potential and may represent an efficient grafting material on guided bone regeneration.