福建省唇腭裂年度及地区发病率的研究

根据福建省22所医院自1986年10月至1992年12月6年间住院分娩的资料整理。在139882名新生儿中有唇腭裂患儿104例，其中单纯唇裂61例，单纯腭裂28例，，唇裂伴腭裂115例，福建省唇腭裂发病率为1．46‰。作者进一步对六年度发病率及发地区的发病率进行了探讨，结果福建省六年的年平均发病率为1．50‰，但发病率与年份变化无显著意义。福建省沿海及非沿海地带的发病率无显著差别，但九地区的地区发病率则有差别，最高为2．06‰，最低为0．69‰。     

Quantitative study of velopharyngeal function post-palatoplasty]

The computer of nasopharyngeal fiberscope(NPF) for quantitative analysis was carried out to assess the palate articulation of 43 subjects,and normal articulation of 60 subjects.The rest,/a/,/s/and /m/ articulation of NPF pictures were calculated for veloparyngreal function via computer.     

Education of dentists in China

China is geographically located in the east of Asia and its population exceeds 1.3 billion. An understanding of dental education in China is thus of interest. However, as there is little published information on this topic, this paper provides information about China regarding its dental history, dental school system including curriculum and dental licensure. High school graduates take a nationwide entrance examination to apply for dental school, of which there are more than 50 in China. A five year dental education leads to the BDS degree. Dental school graduates must then pass the nationwide licensure examination to practise dentistry. Currently, there are not adequate numbers of dentists to provide the necessary oral health care for people living outside metropolitan areas.     

Brain activation patterns during unilateral premolar occlusion

Objective: To observe the characteristics of brain activation during unilateral premolar occlusion.

Methods: Functional magnetic resonance imaging was collected from 10 healthy volunteers during occlusion of the left first premolar (L1), left second premolar (L2), and right first premolar (R1). The brain activation patterns were analyzed, and the primary sensorimotor cortex, supplementary motor area, insula, thalamus, and prefrontal cortex were chosen as regions of interest.

Results: Single premolar occlusion activated the precentral gyrus, postcentral gyrus, cerebellum, thalamus, frontal lobe, hippocampus, cingulate gyrus, and parietal lobe. The brain areas showing activation during single premolar occlusion were similar to those activated by chewing. The activation pattern of L1 was more similar to that of L2 than R1. No significant left and right hemisphere differences in signal intensity were detected within the regions of interest.

Conclusion: Brain activation patterns from two ipsilateral premolars were more similar than the pattern from a contralateral premolar.     

Resazurin metabolism assay for root canal disinfectant evaluation on dual-species biofilms

Introduction

Endodontic infections are caused by polymicrobial biofilms. Therefore, novel root canal disinfectants should be evaluated not only on single-species biofilms but also on dual- or mixed-species biofilms. A simple, high-throughput assay is urgently needed for this. In this study, the application of the resazurin metabolism assay was investigated for the evaluation of a root canal disinfectant on dual-species biofilms.

Methods

Enterococcus faecalis with or without Streptococcus mutans in biofilms were formed in an active attachment biofilm model for 24 hours. Subsequently, the biofilms were treated with various concentrations of NaOCl for 1 minute. After resazurin metabolism by both organisms was confirmed, treatment efficacies using 0.0016% resazurin were evaluated.

Results

During NaOCl treatments, resazurin metabolism displays a clear dose response, not only in single-species E. faecalis (or S. mutans) biofilms but also in dual-species biofilms. Notably, the assay revealed that the resistance of dual-species biofilms to NaOCl was 30-fold higher than in single-species E. faecalis biofilms. Viability counts on a selected NaOCl treatment (0.004%) confirmed this result and showed the increased resistance of E. faecalis in dual-species biofilms.

Conclusions

Clearly, the high-throughput and low cost resazurin metabolism assay has a great potential for testing novel root canal antimicrobial agents in mixed-species biofilms.     

胶囊粉对可见光固化复合树脂机械性能的影响

目的:改善光固化复合树脂的强度和抛光性能.方法:我们采用悬浮聚合法研制了微胶囊型复合填料粉(MCP),作为光固化改进型(VLC-Ⅱ型)复合树脂的填料.并对其性能进行了测试.结果:在复合树脂中加入15%的胶囊型填料粉,压缩强度可达232.1±9.1MPa,拉伸强度可达48.7±2.3MPa,70000次牙刷磨耗率为0.588%,表面粗糙度为2.8μm.结论:胶囊粉可以显著改善复合树脂的压缩强度,拉伸强度,磨耗及表面抛光性等机械性能.与其它同类产品比较,其机械性能、磨耗性能和表面抛光性能均较优越,且相差显著.     

Effect of desensitising toothpastes on dentinal tubule occlusion: A dentine permeability measurement and SEM in vitro study

Objectives

The purpose of this study was to evaluate the in vitro effectiveness of a new bioglass-containing and two commercial desensitising toothpastes on dentinal tubule occlusion after citric acid challenge or artificial saliva (AS) immersion.

Methods

One hundred dentin discs from human third molars were used. Specimens were randomly divided into five groups (n = 20), Group 1: EDTA-treated dentin; Group 2: brushing with distilled water; Group 3: brushing with Novamin; Group 4: brushing with Sensodyne Freshmint; Group 5: brushing with Colgate Sensitive. In each group, samples were then equally split into two subgroups (n = 10) to test two post-treatments: 6% citric acid challenge or 24 h immersion in artificial saliva. Dentine permeability of each specimen was measured before and after each treatment using a hydrostatic device working at 20 cm H₂O pressure. Data were analysed by two-way repeated measures ANOVA to determine if there were any significant differences within or between groups. Dentine morphology and surface deposits were observed by SEM.

Results

All three desensitising toothpastes significantly reduced dentine permeability and created precipitates on the treated dentine surfaces. Moreover, the reductions in dentine permeability showed partial recovery after a citric acid and artificial saliva immersion. Sensodyne showed significant resistant to acid attack and Novamin exhibited the lowest permeability after artificial saliva immersion for 24 h.

Conclusions

The application of the three toothpastes resulted in effective dentinal tubule occlusion. However, the new bioglass-containing toothpaste (Novamin) represented excellent occlusion effects after brushing treatment and AS immersion, while Sensodyne demonstrated more reduction in permeability when citric acid challenged.     

涎腺腺样囊性癌DNA甲基转移酶与抑癌基因甲基化

目的 通过对DNA甲基转移酶（DNMT）在涎腺腺样囊性癌（ACC）中表达的检测，分析DNMT与ACC抑癌基因甲基化、生物学行为的相关性，探讨DNMT在ACC发生、发展中的作用。方法对60例ACC临床病理标本进行DNMT1、DNMT3b的免疫组化染色，显微镜观察，将观察结果与p16、RASSFlA、DAPK、MGMT、E．cadherin多个抑癌基因的甲基化状况、病理分级、临床分期进行比较，应用Fisher确切概率法进行统计学分析。结果 ①DNMT1在ACC中的阳性表达程度明显高于DNMT3b的阳性表达（P〈0．01）。②DNMT1阳性表达随发生甲基化的抑癌基因个数的增加而增加，DNMT1高、低表达组与抑癌基因高、低甲基化组之间差异有统计学意义（P〈0．05），与RASSFlA基因的甲基化呈相关性（P〈0．01）。③DNMT1的阳性表达程度与ACC病理分级（P〈0．05）、临床分期（P〈0．01）呈正相关，实性成分越多、分期越晚，表达越高。④未发现DNMT3b与抑癌基因的甲基化状况、病理分级、临床分期间的相关性。结论DNMT1可能是ACC体内对维持抑癌基因甲基化起主导作用的甲基化酶，与RASSF1A基因的甲基化、ACC病理分级、临床分期有相关性，在ACC的发生、发展中扮演着重要角色，有可能作为肿瘤预后的评估指标之一。     

TyG指数对非酒精性脂肪肝的预测价值

目的 探讨甘油三酯葡萄糖乘积(triglyceride-glucose,TyG)指数对非酒精性脂肪肝(non-alcoholic fatty liver disease,NAFLD)的预测价值.方法 选取于我院体检且符合纳入排除标准者8059例,按TyG值四分位数分为Q1、Q2、Q3、Q44组,比较各组NAFLD的患病率,采用二元Logistic回归分析各组NAFLD的发病风险,采用ROC曲线评价TyG指数对NAFLD的预测价值.结果 共检出NAFLD患者3062例,其年龄、血压、空腹血糖、ALT、ALP、GGT、UA、TG、TC、LDL-c水平均高于未检出者(P<0.001),HDL-c水平低于未检出者(P<0.001).按TyG值四分位数分组,各组NAFLD的患病率随TyG值的增加而升高(x2=1561.2,P<0.001).Logistic回归结果提示NAFLD的发生风险随着TyG值的升高而增加,且进一步校正性别、年龄、血压、各生化指标等混杂因素后Q2组、Q3组、Q4组患NAFLD的风险分别为Q1组的1.8、2.8、4.4倍.ROC曲线分析显示TyG预测NAFLD时的曲线下面积为0.772,其最佳诊断切点是8.59.结论 TyG指数对NAFLD的诊断预测价值较高,是一种NAFLD的新型简易预测指标.