两种脱钙方法对人牙齿脱钙效果的研究比较

目的比较两种不同脱钙方法对人牙齿脱钙时间和脱钙后染色的效果,旨在为人牙齿组织切片观察寻找一种快速且有效的脱钙方法。方法选取40颗健康第三磨牙固定后分为A、B两组,A组使用混合酸脱钙法,B组使用EDTA与超声微波联合脱钙法,记录脱钙完成时间,脱钙完成后常规脱水、包埋、切片,行HE染色,正置显微镜下观察组织形态。结果 A组和B组完成脱钙所需时间分别为:63～74d、20～31d,且B组切片HE染色效果较A组好。结论EDTA与超声微波联合脱钙法完成人牙齿脱钙时间短,且切片HE染色效果好,是一种适合进行人牙齿脱矿的方法。     

牙及牙周组织联合切片的脱钙方法探讨

目的研究牙和牙周组织联合切片脱钙方法。方法成年犬磨牙及牙周组织标本21块，分成7组，分别用6种甲酸及EDTA脱钙，测定脱钙液的pH值、脱钙时间、标本重量、体积和脱出的钙量及各种染色效果等指标判定。结果脱钙液pH值低脱钙快，脱钙后标本重量减轻37．54％、体积缩小25．97％，每克湿重标本脱出的钙量为174．49mg。EDTA脱钙染色效果最佳，脱钙慢。Plank—Rycho脱钙液较迅速，切片质量和染色效果不佳。以氯化铝为保护剂的甲酸脱钙液，切片质量和染色效果优良，比EDTA脱钙迅速。结论以氯化铝为保护剂的50％甲酸是较理想的脱钙液。     

4种脱钙法的效果及其对人牙Ⅰ型胶原免疫组化染色的影响

目的:比较微波、超声、微波超声联合、常温下对人牙的脱钙效果及其对Ⅰ型胶原蛋白免疫组化染色的影响.方法:40个牙随机分为4组,分别在微波、超声、微波超声联合、常温下用100 g/L乙二胺四乙酸二钠(EDTA-2Na)液脱钙.应用SABC免疫组化染色技术检测Ⅰ型胶原蛋白在各组牙体组织中的表达情况.结果:微波、超声、微波超声联合组均较常温组脱钙时间缩短;微波超声联合组脱钙所需时间最少,且Ⅰ型胶原蛋白免疫组化染色效果最好(P＜0.05);微波组脱钙时间较超声组略短,但二者免疫组化染色效果无显著差异(P＞0.05).常温组免疫组化染色结果最差.结论:微波超声联合法脱钙速度较快,石蜡制片染色效果较好,是一种较为理想的脱钙方法.     

大鼠实验性根尖周病的酶组织化学研究

目的：本研究旨在通过石蜡包埋的酶组织化学染色法，观察大鼠实验性根尖周病病损区成骨细胞、破骨细胞的活动情况。方法：将大鼠右下颌第一磨牙开髓后暴露口腔2—28d，诱导根尖周病损形成；对其进行心内固定后，将含牙和牙槽骨的标本经KDTA脱钙，采用石蜡包埋法制作切片，进行酸性磷酸酶和碱性磷酸酶酶组织化学染色。结果：石蜡切片经酶组织化学染色后，可清晰辨别出酶阳性的成骨细胞和破骨细胞。随根尖周病的发展，成骨细胞和破骨细胞在数量上呈一定规律性变化。结论：石蜡切片的酶组织化学法可用于研究根尖周病损区骨细胞的行为变化。     

三种脱钙液对狗牙齿及牙槽骨脱钙效果的比较

作者将１２０颗狗牙骨组织块随机分三组，分别用２５％甲酸－甲醛液加微温、ＥＤＴＡ二钠液及８％硝酸溶液等三种脱钙方法进行脱钙，并比较其优劣．结果甲酸－甲醛液加微温脱钙速度快，组织结构保存良好，酸度适宜，其组织切片行ＨＥ染色时，红蓝反差良好，核染色清晰。     

六种防龋制剂对牙釉质脱矿作用的研究

目的 比较６种含氟及微量元素的防龋制剂对牙釉质脱钙的影响,观察早期龋形成过程中釉质脱钙与时间的关系。方法 选择牛牙８４颗,分为７组,实验区分别用含有相等氟离子的氟化锶,氟化亚锡氟阳酸铵,氟化锌,氟化镧,氟化钠及去离子水处理,所有样本浸泡于乳酸凝胶中形成人工釉质龋,经过对不同浸泡时间酸蚀酸胶中的钙含量的观测,各组样本４８小时以前釉质脱钙量时间的变化有所不同,４８小时以后酸蚀凝胶中钙含量趋于恒定,结果     

肝素对大鼠下切牙釉原蛋白水平及细胞凋亡的影响

目的建立肝素诱导骨质疏松大鼠模型,观察肝素的应用对大鼠下切牙釉原蛋白水平及其细胞凋亡的影响。方法取24只4周龄清洁级Sprague-Dawley(SD)大鼠随机分为两组,实验组每日于腹部皮下注射肝素1U/g,对照组于相同部位注射等体积0.9%氯化钠溶液。4周后取大鼠右侧股骨测骨密度值。同时取下颌骨,沿正中联合分为两份,一侧颌骨及下切牙脱钙后制作石蜡切片,行釉原蛋白免疫荧光染色;另一侧脱钙后制作石蜡切片,行原位末端标记(TUNEL)染色,观察下切牙细胞的凋亡情况。实验数据采用SPSS17.0统计软件包进行统计学分析。结果实验组大鼠股骨的骨密度值为(0.185±0.006)g/cm2,低于对照组的(0.196±0.011)g/cm2;实验组下切牙釉原蛋白免疫荧光染色强度为(0.0432±0.0043),低于对照组的(0.0570±0.0096);两组骨密度及荧光强度差异均具有统计学意义(P<0.05)。实验组未见细胞凋亡发生,对照组可见个别成牙本质细胞及中间层细胞凋亡阳性着色。结论肝素可诱导大鼠骨质疏松,降低下切牙釉原蛋白表达及抑制细胞凋亡的发生。     

两种抗原修复法对牙-牙周免疫组化切片的影响

目的：观察两种抗原修复法对牙-牙周联合组织切片质量的影响。方法：应用两种方法进行抗原修复,PV两步法免疫组化染色,对比观察染色效果和组织脱片情况。结果：高压加热抗原修复法：染色效果好,但软硬组织脱片严重,难以获得完整染色切片。酶消化抗原修复法：硬组织脱片明显改善,可获得完整染色切片,染色强度稍弱,但抗原暴露情况良好,不影响最终的实验结果。结论：为获得完整软硬组织联合切片免疫组化染色观察,酶消化抗原修复法是比较理想的抗原修复方法。     

塑料包埋技术在口腔硬组织切片中的应用研究

目的 利用国内现有病理切片设备，通过对塑料包埋技术制作口腔砭组织切片及磨片的方法、步骤以及染色法的研究，确定其操作过程中的关键步骤以及需注意的问题。方法 选取带牙颌骨以及带种植体的动物下颌骨为材料，进行塑料包埋，用德国Leica公司生产的切片机制作薄切片或磨片，进行染色观察。结果 与用石蜡包理相比，不脱钙骨组织经塑料包埋后，可以制作出1μm的薄切片，以及30μm左右的磨片。切片染色后，可以观察到矿化骨矿化的过程，以及种植体周围骨组织的生长情况和二者的结合程度。结论 利用塑料包埋并配合重型切片机制作切片，可以进行骨组织矿化程度的研究与分析、牙齿龋病研究，以及种植体与骨组织结合情况的研究。这些都是石蜡切片所不能完成的。     

不脱钙的牙齿骨骼塑料包埋制片技术及方法探讨

牙齿和骨骼中含有大量无机钙盐,硬脆致密,难切易碎。常规的牙齿骨骼石蜡切片方法需脱钙后变软才能切片,这种切片不能对钙的分布等矿化程度进行观察研究。塑料包埋是一种新兴的制片技术,能保留矿化结构进行组织病理形态学观察。本文介绍甲基丙烯酸甲酯（methyl methacrylate,MMA）包埋制片技术并对其方法进行探讨。     

不同剂型玻璃离子水门汀溶解性比较研究

目的:研究、比较不同剂型玻璃离子水门汀的溶解性和表面微观形态改变,为临床使用提供依据.方法:将3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)及GC玻璃离子水门汀(双糊剂型)分别在人工唾液中浸泡30 d,冷热循环15000次,烘干测重,比较前后质量变化,计算溶解率,并用扫描电镜观察表面微观改变.结果:不同剂型的玻璃离子水门汀溶解率由高到低分别为3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(双糊剂型).3种玻璃离子水门汀经浸泡溶解后,SEM扫描表面微观形态可观察到GE玻璃离子水门汀(双糊剂型)表面形态改变较少,其他2组玻璃离子水门汀表面微观改变较多.结论:双糊剂型玻璃离子水门汀理化性能及溶解率均低于传统水粉剂型,是未来临床修复治疗的的良好选择.     

Evidence of the validity of a model of determinants of quality of restorative dental care

A model describing the relationship between self-reported quality of restorative dentistry and dentist characteristics for 119 Montana general dentists is presented. The best predictors formed a significant model explaining 22% of the variance of the quality measure. Results are contrasted with a previous estimation of the model for 102 Washington general practitioners. Evidence for the external validity of the model is presented.     

Design of clinical trials of traditional therapies of periodontitis

The present paper on the design of clinical trials of periodontal therapy first addresses the issue of the etiology of periodontal disease. It is suggested that most if not all forms of destructive periodontal disease are caused by microorganisms and that there are different forms of disease with different microbial etiologies. The progressive nature of destructive periodontal disease is subsequently discussed and it is emphasized that, in a given patient, periodontal sites which show signs of inflammation and attachment loss may not over a period of several months and years show further sign of attachment loss. The present methods of assessing periodontal disease do not allow us to discriminate between potentially active and inactive sites in untreated patients. The significance and variability of indicators of periodontal disease such as bleeding on probing, probing pocket depth and probing attachment level measurements are discussed. The errors inherent in the various measurements are analyzed and suggestions are presented describing how alterations in any of the above parameters could be identified and presented in a clinical trial. Of concern for the statistical analysis of clinical data of periodontal disease is the definition of the "experimental unit". For a number of years, the "experimental unit" in periodontal trials was the patient. It is clear, however, that different sites within the same individual show different patterns of disease progression and lesion morphology and often respond differently to periodontal therapy. Statistical analyses must consequently be designed which recognize differences in site-to-site infection and lesion morphology within a common host. Until such analyses are available, the investigator should be wary of pooling data within the same individual, since such pooling may obscure meaningful alternatives which may take place in individual periodontal sites. Some goals of periodontal therapy are subsequently identified. 4 goals are discussed more in detail, namely: to establish conditions which will allow the patient to maintain a dentition without further breakdown of the periodontium; to reduce pocket depth to establish an anatomy in the dentogingival region which with proper maintainance care will prevent the re-establishment of the subgingival infection; to gain attachment as a result of treatment; to assess the effect of a certain chemotherapeutic agent on periodontal disease.     

Experimental evidence of formation of imines in the course of reduction of hydrazones

The reduction of hydrazones is generally suggested to proceed through a reductive cleavage of the nitrogen–nitrogen bond followed by a reduction of the carbon–nitrogen bond. This sequence of reduction processes is here supported for fluorenone (V) and benzophenone (VI) hydrazones as well as by a comparison of the reduction of fluorenone and benzophenone hydrazonium ions (I,III) with corresponding imines (II,IV). Another proof of the presence of imines as intermediates is the splitting of four-electron waves of hydrazones V and VI and hydrazonium ions I and VIII into two waves at pH < 2. This has been interpreted as due to differences in slopes dE_1/2/dpH and pK_a-values of protonated hydrazine derivatives on one side and corresponding imines on the other. In this pH-range imines formed in reductions of VI and VIII are reduced in a single two-electron wave, those of I and V in two one-electron steps. Fluorenone imine (II) is sufficiently stable to allow recording of time-independent current–voltage curves between pH 6 and 11. In this pH-range the imine (II) is reduced in two one-electron steps. Benzophenone imine (IV) has been found stable between pH 4.6 and 12. At pH 4.6–8 the reduction of the imine IV takes place in a single two-electron step, at pH 8–12 in two one-electron steps. Final proof of the initial cleavage of the N–N bond is presented by comparison with the reduction of nitrones.     

Evaluation of efficacy of chemiluminescence for diagnosis of leukoplakia

ObjectiveLeukoplakia is the most common potentially malignant disorder preceding oral cancer. Chemiluminescence has been developed as an adjunct to conventional examination for the diagnosis of these potentially malignant disorders. This study was conducted to assess the efficacy of chemiluminescence in the diagnosis of leukoplakia and to compare the results with histopathological examination.Study designA total of 50 patients with leukoplakia were included from the outpatients attending the Department of Oral Medicine and Radiology, Dental Hospital, Bengaluru, Karnataka, India. These patients were subjected to conventional oral examination followed by chemiluminescent examination with Vizilite (Zila, Fort Collins, CO, USA) and biopsy for histopathological confirmation.ResultsThe sensitivity, specificity, positive predictive value, and negative predictive value of chemiluminescence were 93.75%, 55.56%, 78.95%, and 83.3%, respectively. The overall accuracy of chemiluminescence was 80%. A statistically significant association was observed between histopathology results and chemiluminescence results.ConclusionAlthough it is an easy, safe, minimal time consuming, and noninvasive technique, it has only adjunctive utility and it does not replace biopsy for the diagnosis of leukoplakia.     

正常青年Monson球面半径的测量研究

目的测量正常青年Monson球面半径。方法选择60名(男30名,女30名)正常青年制取全口印模,应用立体摄影成像的原理与方法对Monson球面半径进行测量和统计学处理。结果Monson球面的半径平均为10.173 cm,大于理论值10.160 cm,差异有显著性(P<0.01);男、女性球面半径差异无显著性。结论本实验所得到的数据可作为全口义齿修复中记录颌位关系的一个参量。     

Electrodeposition of bilayers of dithiols

We report an electrochemical method to form a bilayer of dithiol. The cyclic voltammogram of the oxidative deposition of an aromatic dithiol on gold from an alkaline aqueous solution reveals two current peaks separated by more than 400 mV. The integrated charge of the oxidative current peak (B) at the most positive potential is twice that of the other oxidative current peak (A). These two oxidative current peaks were characterized by differential capacitance and electrochemical quartz crystal microbalance (EQCM) measurements. A decrease of the capacity by a factor of two, and an increase of the EQCM frequency change by a factor of two were observed when the potential was scanned from a value where only the first oxidative peak (A) is obtained, to a potential where both oxidative current peaks (A and B) are obtained. Infrared spectra show that the aromatic dithiols adsorb vertically at potentials corresponding to the current peak A and they become tilted for potentials corresponding to the current peak B. The simple relationships between the properties of the two oxidative current peaks are found to be compatible with a step-wise oxidative deposition of a bilayer of dithiol.     

正畸患者切牙影像失真发生情况分析

目的研究正畸患者曲面体层片上的切牙影像失真发生情况，并分析其原因。 方法从中山大学附属口腔医院放射科影像数据库中选取500例正畸患者的曲面体层片和头影测量侧位片，所有曲面体层片均采用咬合杆投照，分别从切牙牙体影像放大、缩小、牙根变短、根尖模糊等评价指标分析上下颌切牙影像失真的发生情况，在头影测量侧位片上测量中切牙根尖-对颌切牙切缘的距离，探讨切牙影像失真发生的原因。采用SPSS 19.0统计软件对所得数据进行统计学检验。 结果500例患者中，切牙牙体影像正常者共417例，切牙牙体影像失真者共83例，影像失真发生率16.6%，其中切牙牙体影像放大17例、牙体影像缩小0例、牙根变短30例，牙根影像变短伴模糊36例。影像失真患者的根尖-切缘距离大于影像正常的患者，差异有统计学意义（F = 5 187.18，P = 0）；影像失真患者的覆盖值大于影像正常的患者，差异有统计学意义（F>477，P = 0）。 结论严重牙颌面畸形如反 、深覆盖是导致曲面体层片的切牙影像失真的主要原因之一。     

颌骨动静脉畸形的栓塞治疗

目的：总结直接穿刺结合经血管内介入栓塞治疗颌骨动静脉静脉畸形的经验。方法：收治凳骨动静脉畸形患者6例,均进行了介入栓塞治疗。采用的栓塞材料为附凝血棉纤毛的螺圈,聚乙烯醇泡沫微粒和二氰基丙烯酸对丁酯。数字减影颈动脉造影在PHILIPSV300下完成。结果6例颌骨动静脉畸形患者中4,例急性出血得到了快速、有效控制,1例慢性渗血的右下 骨动静脉畸形患者,介入栓塞治疗,拔除松动的右下凳第一磨牙,有效地控制了出血,另1例伴局部软组织搏动性膨隆的上凳骨动静脉畸形患者,介入治疗后膨隆的搏动性得到明显改善,栓塞治疗后分别随访3－24个月,均未发现有口腔内渗血或出血。随访的X线片上,病灶区可见新骨形成。结论：局部穿刺结合经血管内介入栓塞治疗颌骨动静畸形是一种安全、有效的治疗方法。