两种光固化正畸黏结剂的黏结性能评价

目的:研究光固化树脂加强型玻璃离子黏结剂与自酸蚀光固化正畸黏结剂对金属托槽-牙面黏结的特点。方法:60颗离体前磨牙随机分成6组,每组10颗牙,3组用光固化树脂加强型玻璃离子黏结剂,另3组用自酸蚀光固化复合树脂黏结剂黏结正畸托槽,分别于0.5、24h及冷热循环实验后测试其抗剪强度及黏结剂残留指数,并通过扫描电镜观察树脂—牙釉质面形态。结果:2种材料黏结强度均能超过5MPa。但是,24h自酸蚀光固化正畸黏结剂的强度高于光固化树脂加强型玻璃离子黏结剂的强度(P<0.05)。结论:2种光固化正畸黏结剂能提供正畸临床黏结金属托槽足够的黏结力。     

托槽重复黏结及不同处理方法对抗剪强度的影响

目的:观察正畸托槽脱落后第2、3次黏结时托槽底板残留黏结剂的不同处理方法对抗剪强度的影响。方法:选择60颗离体人前磨牙,随机分成3组,每组20个样本,第1组为更换新托槽组(简称更新组),即在第2、3次黏结时分别更换新托槽;第2组为燃烧去除底板残胶组(简称燃烧组),即在进行第2、3次黏结时对托槽底板上的残留黏结剂进行燃烧处理;第3组为磨除法去除底板残胶组(简称磨除组),即在第2、3次黏结时对托槽底板上的黏结剂进行磨除处理。3组分别按常规操作对黏结托槽进行剪切试验,记录每组抗剪强度数值的变化并观察ARI指数(牙面残留黏结剂指数)。结果:3组托槽初次黏结的抗剪强度分别(10.00±2.95)MPa;(9.57±2.45)MPa;(9.09±2.58)MPa;更新组第2、3次黏结的抗剪强度分别为(9.55±2.84)MPa;(10.32±2.59)MPa。燃烧组第2、3次黏结抗剪强度分别为(7.30±2.15)MPa;(7.14±1.93)MPa;磨除组的第2、3次黏结抗剪切强度分别为(12.13±2.93)MPa;(12.86±3.08)MPa;燃烧组抗剪强度下降,磨除组抗剪强度则升高,两者均有统计学意义。结论:黏结脱落托槽时宜采用磨除法对脱落托槽底板上残留的黏结剂进行处理,避免使用燃烧底板残胶的方法。     

不同瓷表面处理方法对托槽与瓷面黏结性能影响的研究进展

瓷表面处理的目的是提高托槽与瓷修复体间的黏结强度，因此瓷表面处理方法是影响两者之间黏结强度的主要因素之一。本文介绍了不同的瓷表面处理方法在提高托槽与瓷面间黏结性能方面的最新研究进展。     

不同方法处理脱落托槽后其抗剪切强度对比研究

目的 观察正畸托槽脱落后再次黏结时托槽底板的不同处理方法对抗剪切强度的影响。方法 选择40颗离体人前磨牙,随机分成4组,每组10个样本,托槽均使用3M UNITEK transbond XT光敏树脂正畸黏结剂黏结。处理方法分别为更换新托槽组（简称更新组）;磨除底板残胶组（简称磨除组）;托槽底板喷砂处理组（简称喷砂组）;氯仿溶液浸泡溶解托槽底板上的黏结剂组（简称氯仿浸润组）。各样本均采用万能测试机进行剪切强度试验,记录每组抗剪切强度数值的变化并观察ARI指数（牙面残留黏结剂指数）。结果 磨除组、喷砂组抗剪切强度增强,氯仿浸泡组抗剪切强度则减弱,三者间均有统计学差异。结论 黏结脱落托槽时可采用磨除法或喷砂法对脱落托槽底板进行处理。     

不同表面处理方法对陶瓷托槽与不同瓷修复体粘结强度影响的研究

目的:评价不同瓷修复体试件经过3种表面处理方法后与陶瓷托槽粘结强度的关系。方法:钴铬烤瓷、铸瓷、锆瓷及聚合瓷4类试件经过喷砂(SB)、氢氟酸酸蚀(HFA)、喷砂+酸蚀(SB+HFA)处理后表面涂布硅烷偶联剂(SCA),再粘接陶瓷托槽,经37 ℃恒温水浴24 h 后检测粘接强度(SBS),扫描电镜观察托槽粘接前修复体表面的粗糙度及去除后修复体表面粘接剂残留情况。结果:钴铬烤瓷、铸瓷和聚合瓷试件的抗剪切强度分别与锆瓷试件比较差异有统计学意义(P＜0.05);钴铬烤瓷和铸瓷试件的抗剪强度比较差异无统计学意义。扫描电镜结果显示4组试件表面粗糙度都有明显增加。而喷砂组和喷砂+酸蚀组试件表面的粗糙度明显高于酸蚀处理组;喷砂和喷砂+酸蚀组的表面处理效果差异不大,喷砂组的4类试件表面粘结剂残留最少。结论:3种表面处理方法均能满足临床正畸的需求。喷砂组去除托槽后对试件表面的影响最小,喷砂联合酸蚀处理并不能显著增加剪切强度。 [关键词] 陶瓷托槽 剪切强度 瓷修复体 表面处理     

预调金属托槽再次黏结前底板处理方法的探讨

目的对预调金属托槽重新黏结前底板的不同处理方法作一探讨。方法选择因正畸需要而拔除的离体前磨牙30颗,首次黏结预调金属托槽,24h后予以去除,以此离体牙齿和托槽为实验标本,将牙齿随机分为3组,每组10颗。A组黏结新托槽;B组和C组黏结旧托槽,其中B组托槽底板经火烧后超声波清洗处理;C组保留底板槽沟内的黏结剂而将底板磨平。0.5h后比较3组的剪切强度及ARI评分。结果3组之间的抗剪切强度无显著性差异,3组黏结剂残留指数比较显示C组样本在去除托槽后黏结剂残留在牙面上较少。结论预调金属托槽再次使用前保留底板槽沟内黏结剂的处理方法可能是一种更好的方法。     

正畸粘接剂与瓷面粘接剪切强度的实验研究

目的研究三种不同釉质粘接剂在两种瓷表面处理方式作用下对正畸托槽与瓷粘接剪切强度的影响。方法使用两种不同的瓷表面处理方式处理瓷面,再分别使用三种不同釉质粘接剂粘接金属和陶瓷托槽,在37℃水浴条件下24小时后冷热循环500次(5℃-55℃),测量其粘接剪切强度,并统计粘接剂残留指数。结果瓷表而处理方式与粘接剂种类对粘接强度均有影响,光固化和双组分型化学固化粘接剂粘接强度优于非混合型化学固化粘接剂。结论三种粘接剂在两种不同瓷表面处理方式下均可用于托槽与瓷面的粘接。     

瓷面处理对金属托槽与瓷面粘接性能的影响

目的　研究瓷表面不同处理方法对金属托槽与瓷修复体的粘接强度及去粘接后瓷面完整性的影响。方 法　根据使用粘接剂和表面处理方法的不同,将80个瓷面随机分为8组,每组10个瓷面。分别用京津釉质粘接剂 和光固化复合树脂粘接,表面处理分别行37%磷酸酸蚀、9·6%氢氟酸酸蚀、打磨去釉、瓷面涂硅烷偶联剂4种表面 处理法。试件粘接托槽后经37℃恒温水浴24 h后测定抗剪切强度,记录去粘接后的瓷面破裂情况。对磷酸酸蚀, 氢氟酸酸蚀、打磨去釉的瓷面进行扫描电镜观察。结果　采用氢氟酸酸蚀、打磨去釉、硅烷偶联剂组的粘接抗剪切 强度明显高于磷酸酸蚀组(P<0·01)。打磨去釉后用光固化复合树脂粘接及氢氟酸酸蚀或瓷表面涂硅烷处理后使 用任意一种粘接材料粘接均取得有效的粘接强度。各组去粘接后的瓷破裂率无显著性差异(P>0·05)。结论　氢 氟酸酸蚀、打磨去釉、瓷面涂硅烷偶联剂均可以明显增加金属托槽与瓷面之间的粘接抗剪切强度。瓷面涂硅烷偶 联剂是金属托槽与瓷面粘接时良好的表面处理剂。     

口腔正畸学

传统模型与三维数字化模型在平整牙弓间隙分析中的比较研究;安氏Ⅱ类1分类错（牙合）咬合功能的研究;托槽重复黏结及不同处理方法对抗剪强度的影响;功能性矫治力对青春期恒河猴颅颌骨缝影响的组织学观察;瓷表面处理对正畸托槽与瓷黏结抗剪强度的影响;不同自锁托槽系统在牙齿排齐阶段摩擦力的对比实验研究;     

不同处理方法对托槽再黏结强度的影响

目的:比较不同处理方法对金属托槽再黏结强度的影响。方法:选择40颗离体前磨牙为实验对象,随机分为4组。粘结托槽后,选择3组剥离托槽,采用磨除、烧灼、喷砂3种不同托槽底板处理后予以再次黏结,经体外pH循环30 d后,测定托槽的抗剪切强度。采用SPSS 13.0软件包对所得数据进行单因素方差分析。另选取试样通过扫描电镜观察托槽底板的形态及结构。结果:4组间有显著差异,托槽烧灼再黏结组与其他各组间有显著差异,其余各组两两相比,均无显著性差异。结论:托槽底板残留黏结剂经磨除或喷砂处理,可获得与初次黏结相近的黏结强度。     

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.     

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。     

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.     

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     

口底癌34例临床分析

目的探讨口底癌的临床特性、治疗方法及预后。方法对我院自1992—2002年住院治疗的34例口底癌患者进行回顾性分析。结果34例口底癌患者中,男28例(82.4%),女6例(17.6%),男女比为4.7∶1,平均发病年龄58岁。发病部位:前口底22例(64.7%),后口底12例(35.3%)。淋巴结转移率41.2%。单纯手术组、化疗加手术组、放疗加手术组、化疗加手术加放疗组的5年生存率分别为45.5%、60.0%、50.0%、62.5%。结论口底癌以中老年患者好发,男性居多。易发生淋巴结转移,综合疗法疗效较好。