龈下优势菌在金合金、镍铬合金与纯钛表面黏附的实验观察

目的研究龈下优势菌在种植钛与冠修复材料表面的黏附特征。方法将烤瓷冠修复的两种基底冠材料（金铂合金、镍铬合金）分别粘接在种植纯钛板上，与四种龈下优势菌：伴放线放线杆菌（Aa），牙龈卟啉单胞菌（Pg），具核梭杆菌（Fn），中间普氏菌（Pi）共同厌氧孵育，采用菌落形成单位计数法（CFU）量化测定培养试件表面的细菌黏附量；扫描电镜（SME）观察试件表面细菌黏附的情况。结果四种龈下优势菌在金铂合金-钛试件表面细菌黏附量明显多余镍铬合金-钛试件。结论四种龈下优势菌单独附着能力有差异，Aa〉Fn〉Pg〉Pi。金铂合金的组织相容性优于镍铬合金。     

两种冠修复贵金属合金与种植钛对龈下优势菌黏附的影响

目的:研究龈下优势菌在2种冠修复材料(金铂合金与金钯合金)与种植钛材料表面的黏附特征。方法:将金铂合金与金钯合金分别粘结在种植纯钛板上,与4种龈下优势菌:牙龈卟啉单胞菌(Pg),伴放线放线杆菌(Aa),中间普氏菌(Pi),具核梭杆菌(Fn)共同厌氧孵育。采用菌落形成单位(CFU)计数法量化测定培养试件表面的细菌黏附量,扫描电镜观察试件表面细菌黏附的情况。结果:Aa在2组试件上的黏附量最多,其次为Fn、Pg,最少的为Pi;龈下优势菌在金铂合金-钛试件表面细菌黏附量明显多于金钯合金-钛试件。结论:①4种龈下优势菌对同一合金试件的附着能力有差异:Aa>Fn>Pg>Pi。②金钯合金对细菌的生长与黏附有抑制作用。     

不同粗糙度金铂合金和镍铬合金对种植体龈下优势菌粘附性的影响

目的 研究不同粗糙度冠修复材料对种植体龈下优势菌粘附性的影响。方法 选用两种常用冠修复合金材料:金铂合金和镍铬合金。将其制成两种不同粗糙度的试件粘固于种植纯钛板上,分别与4种龈下优势菌牙龈卟啉单胞菌(Porphyromanus gingivalis,Pg)、伴放线放线杆菌(Actinobacillus actinomycetemcomitans,Aa)、中间普氏菌(Prevotella intermedia,Pi)及具核梭杆菌(Fusobacterium nuclertum,Fn)共同厌氧孵育,采用菌落形成单位(colony-forming unit,CFU)计数法量化测定培养试件表面的细菌量,并进行统计学分析。同时扫描电镜观察各种菌在试件上的附着情况。结果 经两两比较,同种合金中粗糙度大的试件四种细菌附着量均大于粗糙度小的(P<0.01);同种粗糙度的试件,金铂合金与种植体钛上各种细菌粘附量均大于镍铬合金与种植钛上的附着量(P<0.01)。结论 在相同条件下,冠修复合金抛光度越高,细菌粘附量越小。体外培养镍铬合金上四种细菌的粘附均小于金铂合金。     

表面粗糙度对铸造纯钛表面细菌粘附影响的临床研究

目的 评价不同表面形态与表面粗糙度在对纯钛在口腔内戴用0．5年后的细菌粘附量与种类的影响。方法 常规制作纯钛铸造试件30个,分为皱纹形和不同粗糙度的平面形共5组。选择6名口腔粘膜健康的无牙颌受试者,在其上颌总义齿基托磨光面和组织面的不同部位粘固试件。戴用义6个月后,检测各组试件粘附细菌的情况。结果 ①患者个体因素对纯钛铸件表面粘附的细菌量明显的影响,但对细菌地染色分类影响不明显。②同一患者,试件表面粗糙度增加,细菌量明显增大（P＜0．01）,但细菌组成无明显变化;皱纹形试件比平面试件滞留的细菌数量多,除G^＋球菌外,还附着G^-球;相同粗糙度的2个试件,放于组织面者滞留的细菌数量比磨光面者明显减少（P＜0．01）,且前者粘附的主要为G ^-球菌和杆菌。结论 从有益牙周组织健康的角度看,制作纯钛修复体时应可能采用平面形钛制修复体,磨改后应重视抛光,尤其是组织面。     

钛材表面烤瓷的瓷金属界面研究

目的：研究瓷与钛材界面形态学特征和元素扩散情况。方法：在钛材面上烧烤低温瓷Ｃｅｒａｔｉｎ，用扫描电镜和金相显微镜观察钛材和瓷界面区域及材料组织结构。用能谱分析仪观测界面区元素扩散情况。用ＰＷ１７００型自动化粉末衍射仪测定钛板作热处理后表面新生的氧化物。结果：显微镜下，在钛材表面该瓷有良好的浸润性和扩散作用，对钛材附着紧密，ＴＣ４面向界面区出现结构变化层。能谱分析发现界面区有钛、铝、硅元素扩散现象。Ｘ线衍射检查揭示ＴＡ２、ＴＣ４表面都有ＴｉＯ２形成。结论：Ｃｅｒｃｔｉｎ和钛材热力学性能匹配，其结合机理包括机械性结合和化学性结合。     

兔颅骨缺损修复中对多孔块状β—磷酸三钙陶瓷可吸收性？…

目的：通过多孔块状β－磷酸三钙（β－ＴＣＰ）对兔颅骨缺损的修复，定量测量其在体内的吸收速度。方法：２４只家兔随机分为２，４，８，１２周４个时间点组，每组６只动物，分别将β－ＴＣＰ及羟基磷灰石（ＨＡ）样本种植在兔左右顶骨的缺损处，于术后２，４，８，１２周取材，采用“数点法”计算各组材料的剩余量。结果：１２周时β－ＴＣＰ组材料剩余３４．５４％，材料吸收了４０．０１％。结论：多孔块状β－ＴＣＰ陶瓷作为骨     

牙科激光焊钛机械性能的研究

目的 探讨不同条件下牙科激光焊钛的机械性能。方法 采用国产Ｎｄ－ＹＡＧ激光器在不同激光能量条件下分别焊管ＴＡ２和Ｔｉ－６Ａｌ－４Ｖ,利用Ｉｎｓｔｒｏｎ万能拉伸实验机测定其拉伸负荷,０．２％屈服负荷及伸长量,做断口扫描电镜分析,测定焊接区的维氏显微硬度。还测定了试件在人工唾注中浸蚀后焊缝的机械性能。结果 激光焊接接头的强度与材料,电压以及材料和电压的结构均有关系。灯电压为７００－７５０Ｖ时,ＴＡ２的     

贵金属合金及粗糙度对种植体龈下优势菌黏附性的影响

目的:观察2种合金及其粗糙度对种植体龈下优势菌黏附性的影响.方法:选用2种常用冠修复合金材料:金铂合金和金钯合金.将其制成2种不同粗糙度的试件,粘固于种植纯钛板上,分别与4种龈下优势菌Pg、Aa、Pi及Fn共同厌氧孵育,采用菌落形成单位(CFU)计数法量化测定培养试件表面的细菌黏附量.应用SPSS13.0软件包,对试件表面粗糙度的测量值及试件上黏附的菌落数进行统计学分析,同时在扫描电镜下观察各种菌在试件上的附着情况.结果:同种合金中.粗糙度大的试件4种细菌附着量均大于粗糙度小者(P＜0.01);同种粗糙度的试件,金铂合金与种植体钛上各种细菌黏附量均大于金钯合金与种植钛上的附着量(P＜0.01).结论:金钯合金对细菌黏附的影响比金铂合金大,同种合金粗糙度大者.细菌黏附量多.     

纯钛表面改性对细菌粘附的影响

目的：研究氮离子溅射和氮等离子浸没注入对纯钛表面细菌粘附能力的影响。方法：制作纯钛试件288件,各随机选出96件,分别采用氮离子溅射和氮等离子浸没注入对其表面改性,纯钛组为对照组,氮离子溅射组为实验1组,氮等离子浸没注入组为实验2组。在实验1、2组和对照组试件表面粘附血型链球菌、粘性放线菌、白色念珠菌和金黄色葡萄球菌,分别进行细菌体外粘附实验。用菌落形成单位计数法统计分析氮离子溅射和氮等离子浸没注入对各种细菌粘附量的影响。结果：在细菌粘附24h、48h、168h后,上述4种细菌在氮离子溅射组和氮等离子浸没注入组表面粘附量较对照组表面粘附量显著减少（P〈0.001）,其中4种细菌在氮等离子浸没注入组表面粘附量明显少于氮离子溅射组（P〈0.001）。结论：纯钛表面氮离子溅射和氮等离子浸没注入均可抑制细菌粘附,氮等离子浸没注入较氮离子溅射抑制细菌粘附效果更明显。     

类金钢石碳-钛复合体的生物相容性评价-外周血T淋巴细胞亚群测定

目的：了解类金刚石碳－钛复合材料对动物免疫系统的影响。方法：利用化学气相沉积法将类金刚石碳镀于金属镀表面（厚约１μｍ），制成类金刚石碳－钛复合体（Ｄｉａｍｏｎｄ－Ｌｉｋｅ－Ｃａｒｂｏｎ Ｔｉｔａｎｉｕｍ，ＤＬＣ－Ｔｉ），并以纯钛、医用不锈钢、纯铜作对照，分别植入小鼠体内，手术后１、２、３、４和６周检测外周血Ｔ淋巴细胞亚群ＣＤ４、ＣＤ８阳性细胞率及ＣＤ４与ＣＤ８比值（ＣＤ４／ＣＤ８）的变化情况。比较     

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.     

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.     

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。     

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.     

比色板标准与非标准色标识别差异的初探

目的 测试口腔修复学专业研究生对比色板标准色标与非标准色标颜色识别的差异,评价、分析口腔修复学专业研究生临床实际比色能力,为探讨临床比色教学方法提供客观的基础数据.方法 选择具有1～5年临床工作经验、排除色觉识别障碍、经过色彩学知识培训的口腔修复学专业研究生62名.从比色板A(Lineargnide)的29个标准色标中通过随机数字表抽取7个色标作为标准色标,以比色板B(Vita Bleachadgnide 3D-Master)中的7个色标作为非标准色标,在D55标准光源下,以比色板C(Vita 3D-Master)作为比色工具,对标准色标和非标准色标进行比色测试.计算受试者对两种色标比色的总体准确率;统计比色正确的人数分布,并进行Monte Carlo确切概率法检验;统计比色结果在明度、饱和度、色相上的等级偏差,并进行Wilcoxin符号秩和检验.结果 受试者对标准色标比色的总体正确率为45.9%(199/434),对非标准色标比色的总体正确率为9.0%(39/434);对两种色标比色正确的人数分布的差异有统计学意义(P<0.001);对两种色标比色结果的明度等级偏差[分别为0.2(0.1～0.3)、0.4(0.4～0.5)]、饱和度等级偏差[分别为0.2(0.1～0.4)、0.5(0.4～0.6)]的差异均有统计学意义(P<0.01),色相等级偏差[分别为0.3(0.1～0.4)、0.3(0.1～0.4)]的差异无统计学意义(P=0.079>0.01).结论 口腔修复学专业研究生对比色板非标准色标颜色的识别能力明显低于对标准色标颜色的识别能力.     

《口腔医学》杂志2007年度有关信息的分析

目的通过对《口腔医学》2007年全年文献的回顾和分析,了解我国口腔临床医学的研究现状。方法阅读2007年《口腔医学》全年的文献,对各种信息进行了分类汇总,根据设计类型对临床一次性文献进行了分类,并对其中的试验性研究文章进行质量分析。结果《口腔医学》2007年全年的一次性文献274篇,基础和临床文献分别为108和166篇,以临床文献为主(60.58%)。在临床研究文献中,属于观察性、分析性和试验性的文献分别为97、9和60篇,观察性文献所占比例为36.14%,高于以往的报道。60篇观察性文献中,全都设有对照;统计方法应用得当者44篇;真正做到随机、盲法的分别只有4和2篇。结论我国口腔临床方面的研究水平近年来提高明显,但设计的科学性方面有待提高。     

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。