喷砂对不同粘接剂与氧化锆粘接强度的影响

目的研究喷砂对不同粘接剂与氧化锆粘接强度的影响,筛选出比较理想的粘接剂。方法将由ZrO2制成的大瓷片（140个）和小瓷片（140个）随机配对分成14组。对ZrO2的表面分别不作处理和喷砂处理,选用临床常用的7种粘接剂,将较小瓷片粘接在较大瓷片上。置于37℃蒸馏水里保存24h后,进行剪切粘接强度测试,并进行统计学分析。结果喷砂组的粘接强度明显高于非喷砂组（P〈0.01）。PanaviaF、Super-BondC＆B与ZrO2的粘接强度明显高于BifixQM与ZrO2的粘接强度（P〈0.01）。结论喷砂能明显提高粘接剂与ZrO2的粘接强度,Panavia F、Super-Bond C＆B是比较理想的粘接剂。     

不同表面处理和不同粘结剂对氧化锆粘结强度的影响

目的探讨不同表面处理和不同粘结剂对氧化锆粘结强度的影响。方法将氧化锆分别制成直径为12.0mm和4.0mm的瓷片,各120个,分别随机分成12组。粘结剂选用磷酸锌粘结剂、聚羧酸锌粘结剂、BifixQM和Super-Bond CB。对氧化锆的表面分别进行不处理、喷砂、硅烷化、先喷砂后硅烷化处理。用上述4种粘结剂将4.0mm瓷片粘结在12.0mm瓷片上,置于37℃蒸馏水中保存24h后,进行剪切粘结强度测试。结果粘结剂相同时,不同表面处理时的粘结强度有显著统计学差异(P0.01),由小到大依次为不处理喷砂硅烷化先喷砂后硅烷化处理;表面处理相同时,不同粘结剂之间的粘结强度有显著统计学差异(P0.01),由小到大依次为磷酸锌粘结剂聚羧酸锌粘结剂Bifix QMSuper-Bond CB。结论粘结剂相同时,表面处理提高了粘结强度。Super-Bond CB的粘结强度比较理想。使用Super-Bond CB时,喷砂后硅烷化处理是一种比较理想的表面处理方法。     

Effect of surface conditioning methods on the bond strength of luting cements to zirconia

目的 探讨不同表面处理和不同粘结剂对氧化锆粘结强度的影响.方法 将氧化锆分别制成直径为12.0mm和4.0mm的瓷片,各120个,分别随机分成12组.粘结剂选用磷酸锌粘结剂、聚羧酸锌粘结剂、Bifix QM和Super-Bond C&B.对氧化锆的表面分别进行不处理、喷砂、硅烷化、先喷砂后硅烷化处理.用上述4种粘结剂将4.0mm瓷片粘结在12.0mm瓷片上,置于37℃蒸馏水中保存24h后,进行剪切粘结强度测试.结果 粘结剂相同时,不同表面处理时的粘结强度有显著统计学差异(P<0.01),由小到大依次为不处理＜喷砂＜硅烷化＜先喷砂后硅烷化处理;表面处理相同时,不同粘结剂之间的粘结强度有显著统计学差异(P<0.01),由小到大依次为磷酸锌粘结剂＜聚羧酸锌粘结剂＜Bifix QM＜Super-Bond C&B.结论 粘结剂相同时,表面处理提高了粘结强度.Super-Bond C&B的粘结强度比较理想.使用Super-Bond C&B时,喷砂后硅烷化处理是一种比较理想的表面处理方法.     

不同粘接剂及表面处理对氧化锆的粘接强度的影响

目的:评价不同粘接剂及表面处理方法对氧化锆陶瓷与粘接剂的粘接强度的影响.方法:将较大氧化锆瓷片和较小氧化锆瓷片派对,随机分成12组,每组10对.粘接剂选用Ketac Cem Easymix、Rely X luting、Bifix QM和Panavia F,对氧化锆的表面分别喷砂、硅烷化或喷砂联合硅烷化处理,并进行剪切粘接强度测试.结果:在使用Ketac Cem Easymix和Rely X luting时,喷砂提高了粘接强度(P＜0.01).在使用Bifix QM和Panavia F时,喷砂、硅烷化或喷砂联合硅烷化处理提高了粘接强度(P＜0.01).表面处理相同时,Panavia F与氧化锆的粘接强度高于其它粘接剂(P＜0.01).结论:使用Panavia F联合喷砂加硅烷化处理的粘接强度最高.     

3种树脂粘接水门汀与铸造纯钛粘接强度研究

目的：研究3种复合树脂粘固剂与铸造纯钛的粘接强度。方法：用牙科铸钛的方法制作直径分别为4mm和5mm的钛棒,切割成长度为4mm的小钛片。2种规格的钛片配对粘接面用400～1200目碳化硅砂纸在流水下打磨抛光,使之呈均匀一致的平面。50μm氧化铝喷砂,另一组表面不喷砂作为对照,分别使用Super-BondC＆B、Panavia F、Rely X Unicem 3种复合树脂粘固剂粘接。扫描电镜观察喷砂前后铸造纯钛的表面形态。复合树脂粘接剂固化后经37℃恒温水浴24h以及5000次5～55℃冷热循环,测试剪切强度。用SAS的ANOVA过程对各组数据进行分析。结果：喷砂前后纯钛与Panavia F的剪切强度最高,分别为（26.62±3.40）MPa、（23.71±5.28）MPa;5000次冷热循环后,喷砂组的铸造纯钛与Panavia F的剪切强度最高（27.12±8.68）MPa;未喷砂的铸造纯钛与Super-Bond C＆B、Rely X Unicem的粘接强度最低,并且有12.5%的脱落率。结论：本实验结果表明喷砂可以提高Super-Bond C＆B、Panavia F、Rely X Unicem的粘结力和粘结耐久力。不喷砂时,Panavia F与铸造纯钛之间能获得较高的粘接强度和良好的粘接耐久性,喷砂以后优势不再明显。     

不同粘结材料对VITA Mark Ⅱ粘结强度的研究

目的：比较4种常用粘结材料对VITA MarkⅡ可切削陶瓷的粘结强度。方法：应用4种常用粘结材料（Fuji PLUS、Panavia F、RelyX Unicem和FL—BOND＋Beautifil Flow），将切割好的瓷片、牙片粘结，水浴50h后和冷热循环3000次后测其剪切强度，体视显微镜观察粘结破坏情况。结果：水浴50h组中Panavia F、RelyX Unicem和FLBOND＋Beautifil Flow的剪切强度显著高于Fuji PLUS的剪切强度（p〈0．05）。冷热循环3000次组中Panavia F的剪切强度最高，与另3组的差异有统计学意义（p〈0．05）。结论：Panavia F可用于MarkⅡ瓷的粘结，树脂改良型玻璃离子和自酸蚀粘结剂配合流动树脂的初期粘结强度尚可，但冷热循环后粘绪强度下降明显。     

树脂粘结剂与瓷表面处理对全瓷粘结微拉伸强度的影响

目的 研究3种树脂粘结剂配合2种瓷表面处理方法对全瓷粘结微拉伸强度的影响.方法 制作60个体积为5mm×6mm×8mm瓷试件(Empress Ⅱ),抛光后分成两组:对照组和HF SIL组(5%氢氟酸酸蚀20秒,硅烷处理1分钟).分别采用3种树脂粘结剂(RelyX Unicem, Variolink或Panavia F)与复合树脂粘结,37℃保存7天,切割成接触面积为1.0mm2的75个柱形体.试件经热循环(5℃～55℃循环3000次)后,测量粘结微拉伸强度(uTBS).结果 表面处理因素有重要意义(HF SIL组>对照组).对照组中Rely X Unicem的uTBS明显高于Variolink和Panavia F.HF SIL组中经RelyX Unicem和Variolink的uTBS明显高于Panavia F.结论 无论使用何种树脂粘结剂,在粘结前进行酸蚀和硅烷处理都是必要的.     

氧化锆陶瓷表面不同处理方法对剪切强度的影响

目的 研究Cercon氧化锆陶瓷表面不同处理方法对含有磷酸酯粘接单体的Panavia F的剪切强度的影响.方法 采用600号砂纸打磨、喷砂、硅烷化、喷砂加硅烷化4种表面处理方法,对完全随机分组的4组氧化锆陶瓷试样进行单面处理.在玻璃模具的辅助下,将两块不同规格的试样中心相对地用Panavia F树脂类水门汀加压粘接固定,万能实验机测定剪切强度并进行统计学分析.结果 600号砂纸打磨试样剪切强度(21.50±1.98)、喷砂组剪切强度(23.68±2.31)、硅烷化剪切强度(20.69±1.55)、喷砂+硅烷化(24.01±2.19) MPa,其总体均数不相等,其中,喷砂组和喷砂加硅烷化组高于600号砂纸打磨组和硅烷化组,P ＜0.05;喷砂组和喷砂加硅烷化组之间,以及600号砂纸打磨组和硅烷化组之间的差异无统计学意义(P＞0.05).结论 喷砂是提高树脂粘接剂与氧化锆陶瓷剪切强度的有效方法,而砂纸打磨和硅烷化并不能显著提高剪切强度.     

不同树脂水门汀和瓷表面处理对玻璃陶瓷粘结强度的影响

目的：评价4种不同的树脂水门汀以及2种不同的瓷表面处理方法对玻璃陶瓷粘结强度的影响。方法：选用IPse．Max Press热压铸瓷制作直径分别为5mm和4mm，高2mm的圆柱形瓷片。经打磨抛光后分为喇大组：（1）4％氢氟酸酸蚀40sec，（2）4％氢氟酸酸蚀40sec＋硅烷化处理1min。各组内分别选用VariolinkII，Multflink Sprint，RelyX Unicem，BisCem将大小瓷片成对粘固。再分别经37℃水储24h，以及水储后冷热循环5000次测定剪切强度，并用电镜观察瓷片表面形态。结果：硅烷化处理能明显提高粘结强度。经HF＋硅烷处理后Multflink Sprint（31．7±4．5MPa），BisCem（29．2±4．4MPa）和RelyX Unicem（28．1±5．5MPa）3组显示出较VafiolinkII（21．8±4．2MPa）高的粘结强度。冷热循环后除硅烷处理且用VariolinkII和RelyX Unicem粘固的实验组外，其余各组粘结强度均显著下降。结论：4种树脂水门汀与经HF和硅烷联合处理的玻璃陶瓷问能达到理想的粘结强度。     

喷砂结合化学处理对软衬材料粘结效果的影响

[摘要]目的：研究喷砂结合化学处理对硅橡胶软衬材料与基托树脂间粘结强度及基托树脂挠曲强度的影响。方法：制备48块30mm×10mm×7．5mm热凝聚甲基丙烯酸甲酯树脂块,每2个树脂块配成一个试件,24个试件随机分为4组,每组6个试件,即：（1）喷砂组：喷嘴与试件轻接触,采用250txm的氧化铝,在0．62MPa压力下喷砂30S;（2）喷砂＋丙酮组：粘结面喷砂处理同前,喷砂后的粘结面浸泡在丙酮溶液中30S;（3）喷砂＋甲基丙烯酸甲酯单体组（后简称单体）：粘结面喷砂处理同上,喷砂后的树脂块粘结面浸泡在甲基丙烯酸甲酯溶液中180S;（4）对照组：表面不处理。每个试件的两树脂块间衬以3mm厚的软衬材料,冷热循环5000次后,置于万能测试机上,以5mm／min的加载速度测试其拉伸粘结强度。另制备24块65mm×10mm×3．3mm长方体树脂块,分组及表面处理同前,涂布软衬材料粘结剂后测试挠曲强度。结果：喷砂组、喷砂＋丙酮组、喷砂＋甲基丙烯酸甲酯组及对照组试件的拉伸粘结强度分别为（1．31±0．45）MPa、（1．75±0．34）MPa、（1．96±0．50）MPa及（0．90±0．17）MPa。喷砂组与对照组间差别无统计学意义（P〉0．05）。喷砂＋丙酮组及喷砂＋单体组的拉伸粘结强度与对照组相比有统计学差异（P〈0．05）;喷砂＋丙酮组与喷砂＋单体组组间比较无统计学差异;四组间挠曲强度均无统计学差异（P〉0．05）。结论：喷砂结合化学处理树脂表面能增强硅橡胶软衬材料与基托树脂间的粘结强度,且对基托树脂挠曲强度没有影响。     

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.     

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.     

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.     

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.     

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.     

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。     

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。     

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。     

鼻测量法的进展

唇裂术后继发畸形是指唇裂修复术后,仍遗留或继发于手术操作和生长发育变化而表现出来的一类畸形[1]。包括唇畸形、鼻畸形和颌骨畸形。其修复较原发性唇裂修复更复杂,更灵活多变。而导致其修复复杂性的一个重要原因即是局部组织结构复杂变异和缺乏可靠的三维测量手段[2],鼻畸形