不同激光封闭牙本质小管效果的体外研究

目的 研究比较Er:YAG激光和半导体激光对牙本质小管的封闭率和抗老化效果,探讨哪种激光封闭牙本质小管效果更佳,从而为临床选择何种激光进行牙本质脱敏治疗提供理论参考.方法 将25个厚2 mm的牙本质片用0.5％mmol/L的EDTA去除玷污层以制作成牙本质敏感模型,将其中5个样本作为空白对照组,另20个样本随机分成2组...     

牙本质小管封闭剂预防活髓基牙预备后牙本质过敏的临床观察

目的评价牙本质小管封闭剂对活髓基牙预备后牙本质过敏的治疗效果。方法将102例314颗基牙随机分为两组,牙本质小管封闭剂组160颗基牙用氟保护漆治疗,氟化钠甘油组154颗患牙用75%氟化钠甘油治疗。结果牙本质小管封闭剂组有效率为91.88%,氟化钠甘油组有效率为79.87%,两者之间比较有显著性差异（P〈0.05）。结论牙本质小管封闭剂对活髓基牙预备后牙本质过敏有较好的治疗结果 。     

生物活性玻璃对牙本质小管封闭作用的体外研究

目的：本实验通过体外研究比较生物活性玻璃与三种常用脱敏方法对牙本质小管的封闭作用。方法：25颗离体牙制备成敏感牙本质盘模型,随机分成5组（n=5）,分别用3%生物活性玻璃（A）、75%NaF甘油（B）、GC护牙素（C）、劲润（D）、去离子水（E）处理,用扫描电镜（SEM）评估各组封闭牙本质小管的效果。结果：A 组牙本质小管口封闭率100%,高于B、C、D、E组（P均<0.05）。结论：四种脱敏剂中质量分数为3%的生物活性玻璃溶液对牙本质小管口封闭效果最好。     

两种脱敏剂对活髓牙预备后牙本质小管封闭作用的扫描电镜观察

目的评价对比劲润牙本质保护膜与日进MS脱敏剂对活髓牙预备后牙本质小管的封闭作用。方法将因正畸原因拔除的新鲜前磨牙36颗牙体预备后随机分成3组,表面分别涂布劲润,日进MS脱敏剂和不作处理;每组再分为3小组,分别为空白组,玻璃离子粘固组和聚羧酸锌粘固组;最后使冠脱位、冷冻电镜观察牙本质表面变化,并计数统计牙本质小管封闭数。结果两种脱敏剂均有较高的堵孔率,使用水门汀粘固后劲润组与日进MS组的堵孔率差异有统计学意义(P<0.05)。结论两种脱敏剂均可封闭活髓牙预备后暴露的牙本质表面,劲润牙本质保护膜具有更好的弹性和强度,不易被破坏,封闭效果更持久,抗磨损能力也更强。     

牙本质小管封闭剂在烤瓷修复中的临床应用

金属烤瓷修复技术作为一种较为理想的修复方法在临床中广泛使用,为了获得较好的修复体颜色效果及较大的修复体强度就必须有足够的牙体预备量才能创造足够的修复空间。大量的牙体预备难免引起牙本质敏感症的产生成为烤瓷修复中的一大难题,笔者3年来使用格鲁玛（Gluma）牙本质小管封闭剂对预备后的牙体进行处理,较好地缓解了预备后牙体牙本质敏感症的疼痛不适症状,现报道如下。     

牙本质小管封闭剂(美国)的临床应用

牙齿分为牙釉质、牙本质、牙髓等。其中牙釉质是最外面的一层,硬度最高;牙本质位于其中,硬度稍逊;牙本质的内部含丰富的血、神经为牙髓。牙本质的结构非常致密,内有许多牙本质小管,小管内充满了牙本质小管液,与牙髓的     

松香药材中松香酸的含量测定方法

目的建立松香药材中松香酸含量的测定方法。方法用RP-HPLC测定,用Diamonsil C18色谱柱(250mm×4.6mm,5μm),流动相为甲醇-1%醋酸铵溶液(85∶15),流速为1.0ml/min,紫外检测器,检测波长241nm,柱温30℃,检测松香药材中松香酸的含量。结果松香酸在10～250μg/ml的浓度范围内与峰面积呈良好的线性关系Y=40.15X+32.63,(r=0.9999),平均回收率为99.3%(RSD=0.42%)。结论所用方法简便可行,灵敏度高,重复性好,可用于测定松香药材中松香酸的含量。     

牙本质过敏的疗效分析

牙本质过敏是牙本质受到外界刺激,如温度、化学物质以及机械作用等所引起的酸痛症状,在临床上较为常见。本科自2006年9月至2008年9月分别采用氟化钠甘油、Gluma脱敏剂治疗牙本质过敏,并进行疗效比较,现报告如下。     

牙本质粘接剂对窝洞充填效果影响的实验研究

目的：研究不同牙本质粘接剂对窝洞充填后封闭性效果的影响。方法：40颗离体牙随机平分为4组,颊、舌侧制备盒状洞,分别涂Prime＆Bond NT、XenoⅢ、釉质粘结剂后,充填Charisma树脂,剩余一组酸蚀后直接进行树脂充填,经温差循环和染料渗透实验后,体视显微镜下观察微渗漏情况。结果：4组中除Prime＆Bond NT组和釉质粘接剂组间差异无显著性（P〉0.05）外,其余组两两结果比较均具有显著性意义（P〈0.05）,其中对照组与各实验组间差异也具有高度显著性意义（P〉0.01）。结论：Prime＆Bond NT较XenoⅢ具有较好的边缘封闭性。     

脱敏药物对牙本质敏感症患者的临床疗效观察

目的探讨脱敏药物对牙本质敏感症的治疗效果。方法选择笔者所在医院2009年8月～2011年10月口腔科就诊的牙本质敏感症患者53例,共有患牙96颗,分为观察组27例52颗患牙,对照组26例44颗患牙。观察组采用极固宁脱敏剂治疗,对照组采用氟化钠甘油治疗,两组均治疗2周,观察比较两组治疗2周后即刻疗效及1个月后复查疗效。结果治疗2周后,观察组总有效率为98.08%,对照组总有效率为95.45%,两组总有效率比较差异无统计学意义(P>0.05)。治疗1个月后,观察组总有效率为88.46%,对照组总有效率为68.18%,两组总有效率比较差异有统计学意义(P<0.05)。结论极固宁脱敏剂治疗牙本质过敏症有较好疗效,值得临床推广应用。     

3种牙膏用于缓解超声龈上洁治术后牙本质敏感症的疗效观察

目的:观察对治疗超声龈上洁治术后牙本质敏感的疗效.方法:采用区组随机分组法将患者分为3组,分别于超声龈上洁治术后采集基线资料,采用指定的牙膏进行牙面抛光处理,然后按照指导的方法使用指定的牙膏刷牙7天.分别在基线时、抛光完成后以及7天试验结束后测定患者对冷水刺激反应的目测摸拟疼痛评分法(visual analogue scale,VAS)值,以及吹气敏感刺激值.结果:114例患者完成了本试验.在抛光后检查发现:无论是冷水刺激VAS评分还是吹气刺激评分,高露洁专效抗敏牙膏和口腔脱敏糊剂均能有效的减轻牙本质敏感症状.高露洁专效抗敏牙膏与口腔脱敏糊剂和高露洁健白防蛀牙膏相比,冷水刺激VAS评分降低了33.50％和34.25％,吹气刺激评分降低了48.75％和50.48％.在使用相应牙膏刷牙7天后,3组牙本质敏感症状均有所降低.高露洁专效抗敏牙膏与另两组相比冷水刺激VAS评分降低了41.81％和51.86％,吹气刺激评分降低了41.83％和60.96％.结论:在超声龈上洁治术后,使用高露洁专效抗敏牙膏和口腔脱敏糊剂进行牙面抛光能够有效缓解牙本质敏感程度:术后使用3种牙膏刷牙7天均能有效缓解牙本质敏感程度.组间比较发现:无论是在洁治抛光后还是使用相应的牙膏刷牙7天后,与另两组相比较,高露洁专效抗敏牙膏能更好的缓解牙本质敏感症程度.     

脱敏糊剂治疗龈下刮治所致牙本质过敏症的临床疗效观察

目的 评价脱敏糊剂治疗龈下刮治所致牙本质过敏症的临床疗效.方法 将198例龈下刮治后出现牙本质过敏症的患者共538颗患牙随机分为实验组（脱敏糊剂组）286颗牙和对照组（普通牙膏组）252颗牙,分别用口腔脱敏糊剂和普通牙膏刷牙,记录使用牙膏即刻及使用牙膏后4周的牙齿敏感指数,观察其疗效.结果 实验组的即刻疗效有效率36.71%,对照组为29.76%,差异无显著性（P＞0.05）,四周后实验组的有效率为86.71%,对照组的有效率为46.43%,两者比较差异有高度显著性（P＜0.01）.结论 脱敏糊剂治疗龈下刮治后产生的牙本质过敏有着较为理想的疗效.     

Gluma脱敏剂治疗牙本质过敏的疗效观察

目的　评价Gluma脱敏剂对牙本质过敏的治疗效果。方法　将4 0例132个患牙随机分为两组,分别采用氟化钠甘油和Gluma脱敏剂治疗并进行疗效对比。结果　Gluma脱敏剂疗效明显优于氟化钠甘油。结论　Gluma脱敏剂对牙本质过敏有较好的治疗效果     

Comparative evaluation of two chelating agents in collagen fiber network modification over dentinal tubules: An in vitro analysis

ObjectiveTo compare effectiveness of ethylenediaminetetraacetic acid (EDTA) and citric acid in removing collagen fiber network covering dentinal tubules of human teeth.Materials and MethodsEighteen dentin discs were divided in three groups; Gp 1: discs received no treatment (control), Gp 2: discs etched with 17% EDTA (pH = 7.1), and Gp 3: discs etched with 6 wt% citric acid (pH = 4.0). Scanning electron microscopy (SEM) was performed to assess collagen fiber removal and X-ray diffraction (XRD) was implemented to analyse crystal peaks of discs.ResultsThe SEM analysis demonstrated more collagen removal with EDTA treatment compared to citric acid treated specimens. Grade 6 (81% to 100% fiber removal) was mostly achieved for Gp 2 samples whereas grade 2 (1% to 20% fiber removal) was mostly achieved for Gp 3 samples and inter-group comparisons between these groups were statistically significant (p < 0.05). X-ray diffractogram of control and experimental samples demonstrated absence of calcite phase in experimental groups. The change in peak shapes and intensities were observed and citric acid treated samples revealed more intense peaks than EDTA group.ConclusionOur study found 17% EDTA to be more effective in removing collagen fibers when matched with 6% citric acid.     

The effects of locally applied capsaicin on conduction in cutaneous nerves in four mammalian species.

By examination of compound action potentials in the saphenous nerve of the anaesthetized rat it has been shown that capsaicin causes a rapid, dose-dependent, failure of conduction in many C-fibres when applied directly to the nerve. A large reduction in C-fibre conduction occurs with concentrations as low as 110 microM. After a 15-30 min exposure to capsaicin, only partial recovery occurs in 1 h. Similar block of C-fibre conduction occurs in the ferret. However, only smaller, reversible, reductions in C-fibre conduction were seen in the guinea-pig and rabbit, even at the highest concentration of capsaicin used (33 mM). A small reduction in the A delta component of the compound action potential occurred in all four species. In the rat and ferret the effects were much less than those on C-fibres. At high doses, small reversible effects were also seen on the fastest conducting A alpha beta component of the compound action potential in the rat, rabbit and guinea-pig; no effects were seen on the A alpha beta fibres in the ferret. Decreases in amplitude of the compound action potential were accompanied by some slowing of conduction in most cases. The slowing was less than 5% except for the rat A alpha beta and C-fibres and the ferret C-fibres where 9-15% changes occurred at the highest doses of capsaicin. Opening the connective tissue sheath of the nerve did not significantly increase the effectiveness of capsaicin.     

The effects of barium on the electrical properties of the basolateral membrane in proximal tubule

Summary We studied the effects of millimolar Ba²⁺ concentrations on the properties of the basolateral membrane of the proximal tubule in Necturus kidney. Ba²⁺ was added in the peritubular perfusate by means of capillary microperfusion experiments. Basolateral membrane p.d. and conductance were continuously monitored in single tubules (their lumen was filled with oil) during reversible application of Ba²⁺ in peritubular fluid. The effect was membrane depolarization by 14 mV and a decrease of membrane conductance to 63% of control values. This association strongly suggests that the main effect of Ba²⁺ is a decrease of the partial conductance to K⁺ at the basolateral membrane. However, in other experiments, performed also in oil-filled tubules, Ba²⁺ was shown to decrease intracellular K⁺ activity, recorded continously by means of double-barreled (selective vs non selective) K⁺ microelectrodes. This and other, indirect evidence support the hypothesis that Ba²⁺ elicits also a small increase of the partial conductance to sodium at the basolateral membrane.C.N.R.S. Greco 24     

紫冰霜皮肤毒性实验及体外抑菌活性的研究

目的观察紫冰霜对动物皮肤的毒性作用及体外抑菌作用。方法采用健康家兔进行皮肤急性毒性实验和皮肤刺激性实验;采用豚鼠进行皮肤致敏性实验;采用纸片法进行体外抑菌实验。结果紫冰霜对家兔完整皮肤和破损皮肤无急性毒性和刺激性;对豚鼠完整皮肤无致敏作用;对金黄色葡萄球菌、溶血性链球菌、大肠杆菌、铜绿假单胞菌、白色假丝酵母菌具有体外抑菌作用。结论紫冰霜对上述致病菌有一定的抑菌作用,并在治疗过程中具有较好的安全性。     

Bisphosphonates: Pharmacokinetics,bioavailability, mechanisms of action,clinical applications in children,and effects on tooth development

Bisphosphonates (BPs) avidly bind to calcium crystals and inhibit osteoclastic bone resorption, making them useful for treatment of skeletal disorders such as osteoporosis, Paget's disease, osteogenesis imperfecta and metastatic bone diseases. BPs therapeutically act by causing toxic effects on osteoclasts or interfering with specific intracellular pathways in those cells. BPs that possess nitrogen in their composition are called nitrogen-containing BPs (NBPs) and include alendronate, pamidronate, risedronate, ibandronate, and zoledronate. Simple BPs or non-NBPs do not have nitrogen in their composition, include etiodronate and clodronate, and were the first to be tested in animals and clinically used. Because BPs may be administered to pregnant women or children during deciduous and permanent teeth development, it is expected that they might disturb tooth eruption and development. A review of current literature on pharmacokinetics, bioavailability, mechanisms of action, and clinical applications of BPs in children, and their effects on tooth eruption and development is presented.