小鼠釉质发育过程中成釉器中间层细胞增殖、凋亡以及组织非特异性碱性磷酸酶的表达

目的:观察小鼠釉质发育过程中成釉器中间层细胞的增殖、凋亡和其组织非特异性碱性磷酸酶(tissue nonspecific alkaline phosphatase,TNSALP)的表达,探讨中间层在釉质形成过程中的可能作用.方法:取出生后1、3、5、7、9、11、15d的BALB/c小鼠56只,解剖分离含下颌第一磨牙区的下颌骨,脱钙,制片,HE染色进行牙釉质发育情况的组织学观察,分别采用原位末端标记法(TUNEL法)、SP免疫组织化学技术、PV二步法观察中间层细胞的凋亡及检测Bcl-2、增殖细胞核抗原(proliferating cell nuclear antigen,PCNA),并对TNSALP进行组织学定位.通过Image-pro plus 6.0图像分析软件.对图像进行半定量分析.采用SPSS13.0软件包进行t检验、单因素方差分析及SNK-q检验.结果:出生后1d.中间层细胞增殖细胞核抗原由比成釉细胞表达高的强阳性表达逐渐降低;至7d时,其表达为阴性,而且中间层细胞随釉质的发育逐渐凋亡.中间层细胞先于成釉细胞表达TNSALP,出生后5d时即呈现强阳性染色,而后其表达又逐步减弱;成釉细胞7d时开始出现阳性,且呈逐渐增强趋势.结论:中间层细胞的增殖和凋亡及其TNSALP的表达与成釉细胞具有相关性,提示中间层细胞有可能参与成釉细胞的分化及釉质形成.     

玻璃离子水门汀与银汞粘接的剪切力测试

探讨了玻璃离子水门汀增强银汞充填体与牙体之间的粘结作用。取新鲜离体人磨牙制成3mm厚的牙块,在其中央制备直径3mm的圆柱形洞,分别以玻璃离子、银汞粘结剂涂于洞壁,再充填银汞合金,另设空白对照组。两周后测各组的剪切力并作统计学分析。结果表明:玻璃离子与银汞粘结剂组的剪切力比空白对照组大,并有显著差异;说明玻璃离子与银汞粘结剂均有相似的增强银汞修复体与牙体之间粘结力的作用。     

Microbiome of Deep Dentinal Caries from Reversible Pulpitis to Irreversible Pulpitis

Introduction

This study examined the identity of the microbiome of deep dentinal caries and its correlation with the inflammation status of caries-induced pulpitis.

Selective laser sintering technology for customized fabrication of facial prostheses

This article describes the use of SLS to produce a wax prototype for the fabrication of a partial nasal prosthesis. This technique may be an alternative to more conventional laboratory techniques for facial prosthesis fabrication and allows direct generation of definitive wax patterns. With the satisfying effect of nasal defect restoration, patients may be effectively rehabilitated and derive emotional and physical benefit from the treatment provided.     

Effect of using RNA interference to alter iNOS gene expression on the proliferation of tongue squamous cell carcinoma cell line Tca8113

This study used RNA interference (RNAi) to explore the effect of NO and inducible nitric oxide synthase (iNOS) on apoptosis and proliferation in the tongue squamous carcinoma cell line Tca8113. Tca8113 cells were transfected with the plasmid pGenesil-1, which expresses iNOS short hairpin RNA (shRNA), or the negative control plasmid pSilencer-HK, and the transfected cells were compared with untransfected cells. The expression of iNOS was detected by histochemistry, and apoptosis was detected by flow cytometry. The expression of iNOS was significantly lower in the pSilencer-iNOS group than in the pSilencer-HK and empty control groups. The apoptosis rate was significantly higher in the pSilencer-iNOS group than in the pSilencer-HK and empty control groups. Growth monitoring showed that proliferation was also inhibited in cells transfected with pSilencer-iNOS. RNAi gene silencing decreased iNOS gene expression, induced apoptosis, and suppressed proliferation in Tca8113 cells.     

高角儿童面颈部肌肉的肌电活动研究

目的研究高角儿童在不同下颌运动时面颈部肌肉的肌电活动情况。方法用BioEMGⅡ型肌电图仪同步记录14名高角儿童和16名均角儿童在不同下颌运动时双侧颞肌前束(TA)、咬肌(MM)、胸锁乳突肌(SCM)和二腹肌前腹(DA)的肌电活动。结果下颌息止位时,高角组TA、DA和SCM的肌电活动低于均角组,有统计学意义(P<0.01,P<0.05);最大紧咬时,高角组TA和MM的肌电活动低于均角组,有统计学意义(P<0.05);咀嚼口香糖时,高角组MM的肌电活动低于均角组,有统计学意义(P<0.05);吞咽时高角组DA的肌电活动低于均角组,有统计学意义(P<0.05)。结论不同下颌运动时,高角儿童和均角儿童面颈部肌肉的肌电活动差异有所不同;面颈部肌肉的肌电活动可能与颅面垂直形态有关。     

大鼠骨髓基质细胞与胶原复合后修复牙槽骨缺损的研究

目的：探寻以大鼠骨髓基质细胞为种子细胞和胶原复合物为支架材料,构建组织工程骨的原理和方法修复齿槽骨缺损。方法：将SD大鼠骨髓基质细胞（Bone Marrows Stromal Cell,BMSc）进行体外培养并利用矿化液诱导为成骨样细胞,加入胶原（collagen）培养1d后,植入大鼠下颌骨缺损处,2周和4周后处死,取其下颌骨切片,观察成骨效应。结果：术后2周实验侧缺损区可见骨小梁形成,而对照侧无明显骨修复,4周后实验侧新骨形成量逐渐增加,而对照侧只有一些纤维组织修复。HE染色和mallory三色法染色结果也表明实验侧有新骨形成且逐渐增多。结论：应用胶原加体外诱导的成骨样细胞复合体移植可修复大鼠自体的牙槽骨缺损,为组织工程化骨在颌面外科及修复科领域的临床应用奠定了基础。     

牙周炎患者龈沟液和龈组织中IL—8的测定

采用ELISA间接夹心法测定了23名成人牙周炎患者34个患牙龈沟液中的IL-8.并用免疫组织化学法对相应的炎性龈组织进行检测.结果表明IL-8与牙周炎症密切相关,牙周炎龈沟液(GCF)中IL-8检出率为88.24%.IL-8含量范围为0.006～2.772ng/μl.其含量与牙龈指数相关非常显著,与牙周袋深度相关显著,与附着丧失、菌班指数无明显相关.炎性龈组织切片染色表明龈上皮组织和胶原组织中含有大量的阳性染色,从组织学上证明了GCF中IL-8的来源.提示IL-8可能在牙周炎发病机制中起着重要作用.     

Reconstruction of curved mandibular angle defects using a new internal transport distraction device: an experiment in goats

A new internal distraction device, comprising a square-bodied bow, a transport plate, a traction mechanism, and two stabilisers, was developed to allow transportation of bone around an arc. Eight adult goats were studied. A curved mandibulectomy 3cm long was made on the mandibular angle. The distractor was implanted to restore the defect. The bone was distracted at a rate of 1mm per day after a 5-day latent period. Distraction lasted 25 to 32 days. Curvilinear distraction was successful in six of the eight goats. After consolidation periods of four or eight weeks, smooth curved bone masses were restored in the distracted areas. Radiographically, there was considerable bone density in the distraction area and opaque columns streamed in the direction of distraction. Histological examination showed membranous bony regeneration in the restored bone. These results suggest that restoration of curved bone defects using the new internal transport distraction device was feasible in goats.     

金属钛种植体表面蛋白吸附动力学研究

本章应用简单的称重法对等温吸附曲线和吸附动力学曲线进行了粗略的测定，并应用先进的XPS技术对蛋白质在不同pH值下的解吸特性进行研究。发现材料表面的蛋白吸附量随蛋白溶液的浓度的增加和时间的延长而增加，而且在浸泡最初的吸附量增加最快，尤其在前20分钟，吸附几乎就达到了平衡．还发现钛种植体表面的吸附的能力比317L不锈钢的吸附能力强，几乎同时进入吸附的平衡阶段。在体液pH值状态下，钛表面的蛋白吸附量最高，随着pH值向两侧移动，钛表面的蛋白吸附量在下降，而当pH值为25和12时，表面蛋白吸附量降至最小值，pH值继续升高或降低反而表面蛋白的残余量有所升高。