釉基质蛋白对猪骨髓基质细胞黏附、伸展及增殖的影响

目的：研究釉基质蛋白（enamel matrix proteins,EMPs）对体外培养的猪骨髓基质细胞（bone marrow stromal cells,BMSCs）黏附、伸展和增殖活性的影响。方法：抽取猪髂骨骨髓．全血培养法获得骨髓基质细胞。培养液中EMPs的浓度分别为25、50、100、200μg／ml,以不加EMPs为对照。用比色法检测不同浓度EMPs对BMSCs黏附的影响。通过计数预定视野中伸展的细胞数,计算BMSCs在培养1h、3．5h、6、5h后的伸展率。MTT法测定各组细胞的增殖活性。对实验数据行单因素方差分析和SNK法组间比较。结果：猪BMSCs在含有EMPs的培养液中生长良好。对照组以及不同浓度EMPs实验组对细胞黏附的影响无统计学差异。在1h、3．5h、6．5h．各组细胞的伸展率无显著不同。EMPs对BMSCs的促增殖作用呈浓度和时间依赖性．200μg／ml浓度的EMPs从实验的第3天开始．显著促进猪BMSCs的增殖。结论：EMPs对体外培养的猪BMSCs的黏附和伸展无显著影响．200μg／ml浓度的EMPs可显著促进猪BMSCs增殖,为联合应用EMPs和BMSCs修复牙周组织缺损提供了理论依据。     

釉基质蛋白对猪骨髓基质细胞增殖和根面附着生长的影响

目的:研究釉基质蛋白(enamel matrix proteins,EMPs)对体外培养的猪骨髓基质细胞(bone marrowstrom alcells,BMSCs)增殖和在根面附着生长的影响,为EMPs联合应用BMSCs修复牙周组织缺损提供理论依据。方法:抽取猪髂骨骨髓,全血培养法获得骨髓基质细胞。培养液中EMPs的浓度分别为25、50、100、200μg/ml,以不加EMPs为对照。MTT法测定各组细胞的增殖活性。对实验数据行单因素方差分析和SNK法组间比较,检验水准为α=0.05。制备猪自体牙根片,以200μg/mlEMPs处理组为实验组,对照组不用EMPs处理。接种BMSCs后培养7d,HE染色和扫描电镜观察。选取800倍下标准视野,计数每个视野中的细胞数,取4个视野均值。采用配对t检验法作统计学分析,检验水准为α=0.05。结果:猪BMSCs在含有EMPs的培养液中生长良好。EMPs对BMSCs的促增殖作用呈浓度和时间依赖性,200μg/ml浓度的EMPs从实验的第3天开始显著促进猪BMSCs增殖。HE染色显示BMSCs在根片表面附着良好。扫描电镜观察表明实验组附着生长的BMSCs数量较多,与对照组相比具有显著差异。结论:EMPs在200μg/ml浓度时可显著促进猪BMSCs增殖,并促进其在根面的附着生长,提示EMPs和BMSCs可以联合应用以修复牙周组织缺损。     

壳聚糖温敏凝胶负载釉基质蛋白对骨髓基质细胞的作用

目的:探讨在壳聚糖温敏凝胶支架材料中釉基质蛋白(enamel matrix proteins,EMPs)对骨髓基质细胞(bone marrow stromal cells,BMSCs)增殖和碱性磷酸酶(alkaline phosphate,ALP)活性的影响.方法:合成壳聚糖温敏凝胶并加入适当浓度的EMPs,通过考马斯亮蓝试剂盒检测其对EMPs的缓释作用.用全骨髓培养法获得大鼠BMSCs.含10%胎牛血清的DMEM培养液进行原代培养.含EMPs浓度分别为0、50、100、150μg/mL DMEM培养液培养第3代大鼠BMSCs,MTT法测定各组细胞的增殖活性.MTT法及ALP试剂盒检测大鼠BMSCs在负载100μg/mL EMPs及不负载EMPs的壳聚糖温敏凝胶支架材料中的增殖情况及ALP的活性.采用SPSS11.0软件包对实验数据进行单因素方差分析及两样本t检验.结果:EMPs可在壳聚糖温敏凝胶中持续释放3周以上.DMEM培养液中,50μg/mL EMPs组从实验的第3天开始,显著促进大鼠BMSCs的增殖(P＜0.01).壳聚糖温敏凝胶负载100μg/mL EMPs后.于实验的第3天和第5天明显促进大鼠BMSCs的增殖(P＜0.05)并且在实验的第7天(P＜0.05)和第9天(P＜0.01)显著促进大鼠BMSCsALP水平的提高.结论:壳聚糖温敏凝胶对EMPs具有缓释性,负载EMPs后,可以促进大鼠BMSCs增殖,提高ALP的活性.     

釉基质蛋白对人骨髓基质细胞生长和黏附的影响

目的探讨釉基质蛋白(enamelmatrixprotein,EMPs)对人骨髓基质细胞黏附、伸展和增殖的影响。方法用全骨髓培养法获得人骨髓基质细胞,各实验组中EMPs的浓度分别为50、100、200、300μg/ml,以不加EMPs作为空白对照组。细胞计数法测定细胞的黏附能力;通过计数高倍视野中伸展的细胞数,计算骨髓基质细胞在1、3、5和7h的伸展率;MTT法检测各组细胞的增殖活性。采用SAS6.12软件对所得数据进行单因素方差分析。结果体外培养的人骨髓基质细胞生长良好;各实验组间及与对照组比较,对细胞的黏附性的影响无统计学差异;各组细胞的伸展率亦无显著性差异;EMPs对人骨髓基质细胞有较明显的促增殖作用,其中200μg/ml浓度组EMPs对骨髓基质细胞的促增殖作用显著(P<0.05)。结论EMPs对体外培养的人骨髓基质细胞的黏附性和伸展率无影响,但可明显促进其增殖。     

EMPs对人牙髓干细胞增殖分化影响的实验研究

目的：将人牙髓干细胞（human Dental Pulp Stem Cells,hDPSCs）与釉基质蛋白（Enamel Matrix Proteins,EMPs）按一定浓度结合,测定牙本质涎磷蛋白（dentin sialoprotein,DSPP）、波形蛋白（vimentin）、碱性磷酸酶（alkaline phophatase,ALP）的表达,阐述EMPs对人牙髓干细胞增殖分化的影响.方法：分别将浓度为100 μg/mL、200μg/mL的EMPs加入培养中的人牙髓干细胞中,分别于3d、5d、7d、9d、11d对细胞进行免疫组化染色,检测细胞爬片DSPP、vimentin、ALP的表达.结果：未经EMPs诱导的人牙髓干细胞DSPP少量细胞阳性表达,vimentin表达阴性,ALP表现低活性.经200 μg/mL的EMPs诱导5d后,人牙髓干细胞DSPP、vimentin染色呈阳性表达,ALP活性明显增加.结论：EMPs对人牙髓干细胞增殖及分化具有促进作用,200 μg/mL的浓度效果最为显著.     

釉基质蛋白影响人牙囊细胞生物学特性的实验研究

目的:观察釉基质蛋白(EMPs)对牙囊细胞(HDFC)增殖及碱性磷酸酶(ALP)活性的影响。方法:利用酶消化联合组织块培养法获得HDFC。以一定浓度的EMPs作用于牙囊细胞,通过四唑盐比色法和酶动力学方法检测对细胞增殖及ALP活性的变化。结果:EMPs对HDFC具有促增殖作用,其中100mg/L的EMPs的促增殖作用最显著,其促增殖作用可持续至第7天;100mg/L的EMPs可上调ALP活性。结论:EMPs可促进HDFC增殖,影响其ALP活性,可能在牙囊细胞的诱导分化中起重要作用。     

釉基质蛋白对成骨细胞碱性磷酸酶和I型胶原合成的影响

目的 :观察釉基质蛋白 (EMPs)对成骨细胞碱性磷酸酶和I型胶原合成的影响 ,进一步探讨EMPs促进牙槽骨再生的机制。方法 :体外培养MC3T3 E1成骨细胞 ,在培养液中加入不同浓度的EMPs ,用酶动力学方法和MTT法作碱性磷酸酶 (ALP)比活性测定 ,同位素掺入结合细菌胶原酶消化法测定I型胶原的合成。结果 :EMPs能明显促进MC3T3 E1成骨细胞的碱性磷酸酶合成以及I型胶原合成。结论 :EMPs对成骨细胞的生物学活性有明显促进作用 ,提示这可能是EMPs促进牙槽骨再生的一个重要原因     

牙骨质附着蛋白对猴骨髓基质细胞增殖和矿化能力的影响

目的观察牙骨质附着蛋白（CAP）对体外培养的猴骨髓基质细胞增殖及矿化能力的影响。方法抽取猴髂骨骨髓，全血培养法获得骨髓基质细胞。培养液中CAP的浓度分别为0．125、0．25、0．5、1、2μg／ml，以不加CAP为空白对照。MTF法测定各组细胞的增殖活性，同时检测细胞内碱性磷酸酶活性。采用SAS6．12软件对实验数据行单因素方差分析。结果从第3天开始，0．5、1、2μg／ml CAP组与对照组相比能显著促进细胞增殖。对照组与不同浓度CAP实验组对细胞内碱性磷酸酶合成差异无统计学意义。结论0．5～2μg／ml的CAP都能显著促进体外培养的猴BMSCs增殖，但各浓度组CAP对细胞内碱性磷酸酶合成无影响。     

釉基质蛋白对成骨细胞碱性磷酸酶和Ⅰ型胶原合成的影响

目的观察釉基质蛋白(EMPs)对成骨细胞碱性磷酸酶和Ⅰ型胶原合成的影响,进一步探讨EMPs促进牙槽骨再生的机制.方法体外培养MC3T3-E1成骨细胞,在培养液中加入不同浓度的EMPs,用酶动力学方法和MTT法作碱性磷酸酶(ALP)比活性测定,同位素掺入结合细菌胶原酶消化法测定Ⅰ型胶原的合成.结果EMPs能明显促进MC3T3-E1成骨细胞的碱性磷酸酶合成以及Ⅰ型胶原合成.结论EMPs对成骨细胞的生物学活性有明显促进作用,提示这可能是EMPs促进牙槽骨再生的一个重要原因.     

重组人釉原蛋白及猪釉基质蛋白对人骨髓基质细胞成骨作用的比较

目的比较全长重组人釉原蛋白（recombinant human amelogenin, rhAm）和猪釉基质蛋白（enamel matrix proteins,EMPs）体外诱导人骨髓基质细胞（human bone marrow stromal cells,hBMSCs）成骨分化的作用,探讨rhAm促进hBMSCs成骨的调控机制,为rhAm临床应用提供理论依据。方法经诱导表达并纯化得到25 kDa全长rhAm;利用乙酸法提纯猪EMPs,体外原代培养hBMSCs。采用实时定量PCR及Western印迹法检测不同时间点rhAm和EMPs作用hBMSCs后成骨因子（Runx2、ALP、COL-I）的变化,观察时效关系。采用碱性磷酸酶和茜素红染色检测2种蛋白对hBMSCs成骨矿化作用的影响。采用SPSS 13.0软件包对数据进行统计学分析。结果体外培养获得原代hBMSCs。实时定量PCR、Western印迹及细胞染色结果表明,10 μg/mL rhAm和200 μg/mL EMPs均可明显促进hBMSCs中成骨相关因子的基因及蛋白表达,且这种效果和蛋白作用时间有一定相关性。结论rhAm与EMPs均能明显促进hBMSCs成骨,作用效果具有一定的时间依赖性。     

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