糖尿病患者罗格列酮治疗对牙周炎龈沟液可溶性细胞间黏附分子-1的影响

细胞间黏附分子1(imercellular adhesion molecule-1,ICAM-1)主要表达于炎症和免疫反应部位的多种细胞表面,在牙周组织的炎症反应过程中起着重要作用[1].可溶性细胞间黏附分子1(soluble intercellular adhesion molecule-1,sICAM-1)是非特异性蛋白酶裂解ICAM-1产生的,以循环形式存在于体液及龈沟液(gingival,icevicular fluid,GCF)中.本文测定糖尿病伴发牙周炎的患者在用罗格列酮治疗前后龈沟液中sICAM-1的变化.     

SIP1在人舌癌Tca8113细胞中的定位和融合蛋白表达鉴定的研究

目的检测Smad相互作用蛋白1(SIP1)在人舌癌Tca8113细胞系中的定位及融合蛋白的表达鉴定。方法 PCR扩增SIP1编码序列的全长,克隆到pCMV-Flag-MAT-Tag 1载体。利用共聚焦激光扫描显微镜观察SIP1和SIP1-Flag在人舌癌Tca8113细胞系中定位,并将构建好的Flag标签SIP1(SIP1-Flag)真核表达载体转染到人舌癌Tca8113细胞系中,提取蛋白进行Western blot检测,利用Flag标签抗体进行免疫沉淀纯化SIP1-Flag融合蛋白。结果构建了SIP1-Flag真核表达载体。SIP1和SIP1-Flag融合蛋白主要定位于人舌癌Tca8113的细胞核中,Western blot检测到SIP1-Flag融合蛋白表达,且在人舌癌Tca8113细胞中成功纯化SIP1-Flag蛋白。结论成功构建真核表达载体。SIP1和SIP1-Flag主要定位于细胞核,成功鉴定融合蛋白表达并纯化SIP1-Flag融合蛋白。     

S1P/S1PR1通路依赖的压力对破骨前体细胞趋化效应

目的: 探究S1P/S1PR1通路轴在压力下对破骨前体细胞趋化影响的调节作用。方法: 建立体外压力模型,通过实时荧光定量聚合酶链式反应,免疫印迹实验和细胞免疫荧光检测压力下Raw264.7细胞SPHK1和S1PR1的mRNA水平和蛋白水平。采用Transwell 24孔板通过趋化实验探究S1P/S1PR1在压力下对Raw264.7细胞的迁移能力的影响。结果: 发现0.5、1.0和2.0 g/cm²压力作用下,Raw264.7细胞的SPHK1和S1PR1的表达及Raw264.7细胞的趋化显著降低。在S1PR1受体功能性激动剂FTY720作用下,压力作用下趋化能力被抑制的Raw264.7细胞趋化水平显著增加。结论: S1P/S1PR1信号轴在正畸治疗中调节破骨前体细胞迁移与功能发挥重要作用。[关键词] S1P/S1PR1通路 压力 破骨前体细胞 趋化     

长链非编码RNA肌动蛋白纤维相关蛋白1-反义RNA1在口腔鳞状细胞癌中的表达及其相关功能

目的 分析长链非编码RNA（lncRNA）肌动蛋白纤维相关蛋白1-反义RNA1（AFAP1-AS1）在口腔鳞状细胞癌（OSCC）中的表达及其对OSCC细胞生物行为学的影响,初步探讨其可能的作用机制。方法 采用实时荧光定量聚合酶链反应（qRT-PCR）检测OSCC患者（55例）癌组织、癌旁正常黏膜组织及人口腔鳞状细胞癌SCC25、人正常口腔角质细胞株（NOK）细胞中lncRNA AFAP1-AS1的表达,分析AFAP1-AS1与OSCC患者病理特征的相关性,通过Kaplan-Meier生存曲线分析AFAP1-AS1与患者预后的关系。AFAP1-AS1 siRNA转染SCC25细胞,细胞计数（CCK-8）及Transwell实验分别检测细胞增殖、迁移和侵袭的变化,蛋白质印迹（Western blot）检测侵袭相关蛋白、肌动蛋白纤维相关蛋白1（AFAP1）及Rho GTP酶家族成员蛋白的表达情况,免疫荧光染色检测细胞骨架肌动蛋白微丝结构的变化。结果 OSCC组织中AFAP1-AS1的表达高于癌旁正常黏膜组织,SCC25细胞中AFAP1-AS1的表达高于NOK细胞（P<0.001）。AFAP1-AS1的表达与OSCC的分化程度、TNM分期及淋巴结转移密切相关（P<0.05）,AFAP1-AS1高表达患者的生存率低于AFAP1-AS1低表达者（P<0.05）。AFAP1-AS1 siRNA转染后AFAP1-AS1的表达水平下调,SCC25细胞的增殖、迁移和侵袭能力降低,AFAP1、RhoA、Rac2、Rab10、RhoGDI和Pfn1的表达上调,RhoC的表达下调,细胞骨架中应力纤维丝减少,肌动蛋白完整性丢失。结论 lncRNA AFAP1-AS1在OSCC组织及SCC25细胞中高表达,与OSCC的发生进展及预后相关。下调AFAP1-AS1能够抑制OSCC的增殖、迁移和侵袭能力,其可能是通过调控肌动蛋白纤维丝的完整性实现的。     

上皮膜蛋白1真核表达载体的构建及其对人舌鳞状细胞癌细胞迁移和侵袭的影响

目的 构建上皮膜蛋白1（EMP1）基因真核表达载体pEGFP-N1-EMP1,探讨EMP1基因对人舌鳞状细胞癌细胞迁移和侵袭的影响。方法 采用逆转录聚合酶链式反应（PCR）扩增EMP1基因,双酶切法连接至真核表达载体pEGFP-N1双酶切产物大片段,构建pEGFP-N1-EMP1重组质粒。经测序鉴定后,通过脂质体介导法将pEGFP-N1-EMP1重组质粒和pEGFP-N1空载体转染至人舌鳞状细胞癌Tb3.1细胞,荧光显微镜下观察转染后绿色荧光蛋白的表达情况,实时荧光定量PCR法检测转染后24、48、72 h的EMP1过表达水平。利用Transwell迁移及侵袭实验分析EMP1过表达对Tb3.1细胞迁移及侵袭能力的影响。结果 成功克隆EMP1全长基因,经测序分析证实将EMP1基因准确插入真核表达载体pEGFP-N1,转染后细胞可见绿色荧光表达。实时荧光定量PCR结果显示,pEGFP-N1-EMP1重组质粒转染24 h组,Tb3.1细胞中EMP1表达量显著高于pEGFP-N1空载体组、野生型细胞组以及重组质粒转染48 h和72 h组。Transwell迁移及侵袭实验结果显示,EMP1过表达抑制了Tb3.1细胞的迁移和侵袭能力。结论 成功构建了EMP1真核表达载体,并在体外证实了EMP1过表达可抑制舌鳞状细胞癌细胞的迁移和侵袭能力,为进一步研究EMP1基因在口腔鳞状细胞癌转移中的作用及其分子机制奠定了基础。     

全冠修复后重度龈炎患者基因型对IL-1表达的影响

目的：探讨全冠修复后重度龈炎患者基因型对白细胞介素1（interleukin-1,IL-1）表达的影响。方法：根据龈沟出血指数选取重度龈炎组50名,采用37名健康志愿者对照。分离外周血单个核细胞（PBMC）,1ug/ml脂多糖（LPS）刺激培养24h后测IL-1含量。结果：重度龈炎组的IL-1ra浓度和IL-1β/IL-1ra比值较健康对照组有显著性差异（P〈0.05）。与I/I基因型相比较,IL-1RN内含子2等位基因Ⅱ、IL-1RN内含子2和IL-1B＋3953复合等位基因Ⅱ携带组的IL-1ra浓度和IL-1β/IL-1ra比值差异有显著性（P〈0.01）。结论：IL-1RN内含子2等位基因Ⅱ通过影响IL-1ra的表达从而在全冠修复后重度龈炎中发挥重要作用。     

LncRNA RUNX1-IT1对恶性多形性腺瘤miR-195/CyclinD1的调控作用探讨

目的 ：探讨恶性多形性腺瘤(malignant pleomorphic adenoma, MPA)细胞中长链非编码RNA(long non-coding RNA, LncRNA)RUNX1-IT1对微小RNA-195(microRNA-195, miR-195)/细胞周期蛋白D1(CyclinD1)的调控作用。方法：收集手术切除的MPA组织及癌旁组织，检测LncRNA RUNX1-IT1、miR-195、CyclinD1 mRNA的表达水平，分析三者与MPA临床病理的关系。培养MPA细胞系SM-AP1，转染阴性对照(NC)siRNA、LncRNA RUNX1-IT1 siRNA、miRNC、miR-195抑制物，检测细胞增殖水平A490及miR-195、CyclinD1的表达水平，分析LncRNA RUNX1-IT1靶向miR-195、miR-195靶向CyclinD1的关系。采用SPSS 21.0软件包对数据进行统计学分析。结果 ：MPA中LncRNA RUNX1-IT1、CyclinD1的表达水平显著高于癌旁组织，miR-195的表达水平显著低于癌旁组织(P<0.05)。Ln...     

光固化修复体脱落临床分析及预防

分析 1987年以来就诊的光固化修复体脱落患者 140例 ,均为恒前牙 ,且均使用西德古莎光固化树脂材料和杭州新亚仪表公司生产的ＹＨ -Ⅱ型光固化机 (表 1、2 )。表 1　光固化脱落与时间的关系时间 (月 )例数 %3 6 4 .2 96 1 0 7.1 41 2 1 6 1 1 .431 81 7 1 2 .1 42 4 1 3 9.2 930 2 3 1 6 .4336 2 5 1 7.86>36 30 2 1 .43表 2　光固化脱落原因　　原因例数 %继发性龋坏 4 2 .86咬合过高 4 2 .86操作原因 1 91 3 .57时间原因 (>36月 ) 30 2 1 .43咀嚼不慎和外伤 1 81 2 .86未知 65 46 .431　光固化脱落原因分析光固化脱落与时间有关 ,随时间的…     

长链非编码RNA肌动蛋白纤维相关蛋白1-反义RNA1在口腔鳞状细胞癌中的表达及其相关功能

目的 分析长链非编码RNA（lncRNA）肌动蛋白纤维相关蛋白1-反义RNA1（AFAP1-AS1）在口腔鳞状细胞癌（OSCC）中的表达及其对OSCC细胞生物行为学的影响,初步探讨其可能的作用机制。方法 采用实时荧光定量聚合酶链反应（qRT-PCR）检测OSCC患者（55例）癌组织、癌旁正常黏膜组织及人口腔鳞状细胞癌SCC25、人正常口腔角质细胞株（NOK）细胞中lncRNA AFAP1-AS1的表达,分析AFAP1-AS1与OSCC患者病理特征的相关性,通过Kaplan-Meier生存曲线分析AFAP1-AS1与患者预后的关系。AFAP1-AS1 siRNA转染SCC25细胞,细胞计数（CCK-8）及Transwell实验分别检测细胞增殖、迁移和侵袭的变化,蛋白质印迹（Western blot）检测侵袭相关蛋白、肌动蛋白纤维相关蛋白1（AFAP1）及Rho GTP酶家族成员蛋白的表达情况,免疫荧光染色检测细胞骨架肌动蛋白微丝结构的变化。结果 OSCC组织中AFAP1-AS1的表达高于癌旁正常黏膜组织,SCC25细胞中AFAP1-AS1的表达高于NOK细胞（P<0.001）。AFAP1-AS1的表达与OSCC的分化程度、TNM分期及淋巴结转移密切相关（P<0.05）,AFAP1-AS1高表达患者的生存率低于AFAP1-AS1低表达者（P<0.05）。AFAP1-AS1 siRNA转染后AFAP1-AS1的表达水平下调,SCC25细胞的增殖、迁移和侵袭能力降低,AFAP1、RhoA、Rac2、Rab10、RhoGDI和Pfn1的表达上调,RhoC的表达下调,细胞骨架中应力纤维丝减少,肌动蛋白完整性丢失。结论 lncRNA AFAP1-AS1在OSCC组织及SCC25细胞中高表达,与OSCC的发生进展及预后相关。下调AFAP1-AS1能够抑制OSCC的增殖、迁移和侵袭能力,其可能是通过调控肌动蛋白纤维丝的完整性实现的。     

转基因细胞Tca8113/TNF-α的体外致突变性研究

目的　观察转基因细胞Tca81 1 3/TNF α的致突变作用 ,将转基因肿瘤细胞作为“瘤苗”的临床应用的安全性提供依据。方法　利用基因转染技术 ,用逆转录病毒LXSN·TNF α载体系统 ,将肿瘤坏死因子基因 (TNF α基因 )转导入人舌癌Tca81 1 3细胞 ,通过遗传毒理学Ames实验对转基因的Tca81 1 3/TNF α细胞的细胞DNA及其培养上清液进行体外的致突变试验研究。结果　 (1 )DNA组菌落数最大值 (x±s) :1 50 5± 1 1 2 / 1 60 2± 7 6 (TA97) ;34 0± 2 2 / 34 4± 3 2 (TA98) ;1 39 8± 4 6/ 1 30 8± 7 2 (TA1 0 0 ) ;2 64 0± 1 4 6/ 2 54 4± 8 2 (TA1 0 2 )。 (2 )培养上清液组菌落数最大值 (x±s) :1 4 0 5± 1 1 2 / 1 55 2± 7 6 (TA97) ;34 0± 1 0 / 36 4± 7 2 (TA98) ;1 4 5 6± 5 6/ 1 64 4± 6 2(TA1 0 0 ) ;2 54 0± 6 0 / 2 84 4± 8 2 (TA1 0 2 )。结论　TNF α基因转导Tca81 1 3细胞不会引起基因突变 ,转基因细胞作为“瘤苗”的应用初步评价为安全可靠的     

Comparing Predictors of Willingness to Treat HIV+ Patients for New York City Male and Female General Practice Dentists 50 Years of Age or Younger

Objectives : This article develops and compares gender-specific predictive models for willingness to treat HIV-infected patients (PHIV+) for male and female private general practice dentists (GPDs). Methods : Based on mail survey data collected in Manhattan and Queens, New York City (73.3% response rate), hierarchical multiple regression analyses were conducted for male and female dentists 50 years of age or younger ( n =763) and for those in solo practice. Results : The gender-specific predictive models ( R² s=0.72) do not differ, except for the influence of practice viability, a moderately strong, statistically significant predictor for men, while the least powerful, statistically nonsignificant predictor for women. This distinction remains for solo male and female practitioners. Informal/formal collegial norms are more influential predictors within the solo female model than within the solo male model. Conclusion : Findings are encouraging for further work in developing predictive models for clinician subpopulations, with an eye toward developing intervention strategies that reflect key predictive factors for each group.     

北京永定路社区居民口腔卫生服务需要和利用调查

目的了解北京社区居民口腔医疗需要和口腔卫生服务资源利用现况,为推动社区居民口腔医疗保健服务提供参考。方法以世界卫生组织口腔健康调查基本方法为标准,采用随机等比抽样调查方法,对北京永定路社区2 000名居民进行口腔健康检查和问卷调查,了解其口腔医疗需要情况及口腔卫生服务资源利用情况。结果共计1 845人的口腔健康调查表符合要求。其中254人(13.77%)不需要口腔医疗,864人(46.83%)需要择期口腔医疗,715人(38.75%)需要及早口腔医疗,12人(0.65%)需要紧急口腔医疗。社区居民1年内就诊率为39.73%。就诊选择国营口腔专科医院的占37.02%,选择私营口腔诊所的占35.88%。结论社区居民的口腔医疗需求普遍,口腔医疗保健任务艰巨,应加强社区口腔疾病预防控制工作。     

Improvements in methods of periodontal probing: comparison of relative attachment level data selected by outlier reduction protocols from Florida disc probe measurements

OBJECTIVES: To compare relative attachment level data (RAL) selected by the Option-4 algorithm (O-4), Modified Option-4 algorithm (MO-4), Option-3 method (O-3) and Double Pass method (DP) from a common dataset and to determine the most efficient method in eliminating outliers. MATERIAL AND METHODS: A single clinician recorded full mouth RAL with the Florida Disc Probe on four occasions over 6 months in 16 subjects (mean age 48.1 years) with untreated moderate Chronic Adult Periodontitis (mean Probeable Crevice Depth 2.9 mm). RESULTS: 2312 sites were available for analysis. Within-visit correlation coefficients for the two selected RAL measurements were 0.98 (P < 0.001) for O-4, MO-4 and O-3 and >or= 0.92 (P < 0.001) for DP. The maximum mean differences of within-visit RAL were - 0.05 mm for O-4, - 0.03 mm for MO-4, - 0.03 mm for O-3 and - 0.02 mm for DP. The standard deviations of these differences were or= 99.9% sites for O-4, >or= 99.9% sites for MO-4, >or= 99.3% sites for O-3 and >or= 85.6% sites for DP. Remeasurement (in addition to two passes) was required over the study period at 16.6% sites for O-4, 13.2% sites for MO-4 and 13.0% sites for O-3: DP, by definition, required no additional measurements. The mean site-specific variances at all visits were 相似文献   

Comparison of culture and real-time PCR for detection and quantification of five putative periodontopathogenic bacteria in subgingival plaque samples

OBJECTIVES: Bacterial cultivation is a well-established method for analyzing plaque samples. Real-time polymerase chain reaction (PCR) is a novel rapid method for the identification and quantification of periodontopathogenic bacteria that has been recently introduced. In this study, we compared real-time PCR with conventional anaerobic cultivation. METHOD: A total of 78 subgingival plaque samples were harvested from pockets > or =5 mm in 22 patients with advanced chronic periodontitis and immediately transferred into transport medium. Aliquots were evaluated with species-specific probes by real-time PCR (meridol Perio Diagnostics, GABA) and anaerobic bacteria culture on selective media for the detection of Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia and Tannerella forsythensis. The analysis was performed by two separate, blinded examiners. RESULTS: When real-time PCR was compared with the culture method (golden standard) for the detection of putative periodontopathogenic bacteria, the sensitivity and specificity for A. actinomycetemcomitans were 67% and 100%, respectively (kappa: 0.79); for F. nucleatum 73% and 53%, respectively (kappa: 0.21); for P. gingivalis 94% and 84%, respectively (kappa: 0.77); for P. intermedia 33% and 94%, respectively (kappa: 0.26) and for T. forsythensis 92% and 56%, respectively (kappa: 0.51). Spearman's correlation coefficients for the quantitative results of both methods were 0.82 for A. actinomycetemcomitans, 0.33 for F. nucleatum, 0.83 for P. gingivalis, 0.38 for P. intermedia and 0.67 for T. forsythensis. CONCLUSION: Overall, the agreement between both test methods was excellent for A. actinomycetemcomitans and P. gingivalis, fair for T. forsythensis and poor for F. nucleatum and P. intermedia. The discrepancies in the results may be explained by the inability of cultivation methods to distinguish between close related taxa, and the problems of keeping periopathogenic bacteria viable, which is required for standard cultivation.     

An introduction to clinical practice guideline for Chinese undergraduates in stomatology

The Society of Dental Education, Chinese Stomatological Association has formulated the Standards of Clinical Practice for Chinese Undergraduate Students Majoring in Stomatology, on the basis of extensively soliciting the views of experts in various fields. The aim of this standard is to guide clinical teaching and improve teaching quality in schools of stomatology in China. The standards include eight parts: the standard of clinical practice for oral and maxillofacial surgery, for cariology and endodontics, for periodontics, for the oral mucosa diseases, for preventive dentistry, for pedodontology, for prosthodontics and for oral imageology. Each part includes introduction to subjects, the clinical practice time period, the purpose and requirements of practice, the disease types of practice and items of clinical operation, the index of the lowest workload of practice and the major methods of assessment. These standards are not only the basic requirements and guiding principles for clinical teaching, but also the major criteria for assessing the clinical teaching quality of stomatological colleges/schools of China.     

The in vitro effects of cetyltrimethylammonium naproxenate on oral and pharyngeal microorganisms of various ecological niches

The purpose of this study was to determine the in vitro susceptibility to cetyltrimethylammonium naproxenate for various aerobic and anaerobic micro-organisms responsible for oral and pharyngeal diseases by assessing the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) or minimum fungicidal concentrations (MFCs) and by determining kill-times. The MICs of cetyltrimethylammonium naproxenate for 46 tested strains (25 reference strains and 21 clinical isolates) ranged from 8 to 500 micrograms/ml. The MIC was found to be 31.25 micrograms/ml for 36% of the reference strains. Even lower MIC values (15.63 micrograms/ml) were observed for some anaerobic strains, for Haemophilus influenzae and for Candida tropicalis. MIC and MBC values corresponded for the majority of strains tested while the MFC for C. tropicalis and C. albicans was much higher. Only 9.5% of the clinical isolates gave a MIC value of 31.25 micrograms/ml. Enterococcus faecalis, Streptococcus pyogenes and Staphylococcus aureus showed MIC at 62.5 micrograms/ml. The MIC and MBC values among the isolates were comparable, while the MFC value for the yeasts was greater. A concentration of 125 micrograms/ml of cetyltrimethylammonium naproxenate inhibited the growth of all bacteria, except Enterobacteriaceae and Pseudomonaceae, and yeasts. Cetyltrimethylammonium naproxenate shows very rapid kill-time for S. sanguis (0"), and rapid (15") for S. pyogenes, S. dysgalactiae and S. mutans and for Moraxella catarrhalis, while a longer kill-time was necessary for the other microbes tested.     

Intra- and inter-examiner reproducibility in constant force probing

Abstract This study evaluated intra- and inter-examiner reproducibility for a conventional manual probe versus a computer-interfaced force-controlled periodontal probe. 2 examiners recorded probing depths (PD) and relative attachment levels (AL) at 1128 sites in 15 periodontal maintenance patients. Each site was evaluated 2x, 7 to 10 days apart by both examiners. Probing force for the electronic probe was 15 g. PD intra-examiner reproducibility (within ± 1.0 mm) for shallow sites (PD3 mm) was 98.6% versus 91.5% for the conventional versus the electronic probe for examiner 1 and 98.5% versus 88.7% for examiner 2. Corresponding values for deeper sites (PD>3 mm) were 96.4% versus 85.9% for examiner 1 and 95.1% versus 77.0% for examiner 2. Generally, AL intra-examiner reproducibility was 1 to 3% lower than for PD. PD inter-examiner reproducibility (within ±1.0 mm) was 99.2% versus 90.7% for the conventional versus the electronic probe, respectively, for shallow sites and 95.4% versus 76.9% for deeper sites. AL inter-examiner reproducibility (within ± 1.0 mm) was 1 to 5% lower than for PD. Both intra- and inter-examiner reproducibility was higher for anterior than for posterior sites. Mean PD and AL were similar for both examiners. However, the electronic probe consistently recorded 0.1 to 0.2 mm higher values than the conventional probe. Standard deviations indicated a greater variability for electronic than for manual probing. The results suggest that intra- and inter-examiner reproducibility may not necessarily be higher with an electronic, force-controlled periodontal probe than with a conventional manual probe.     

Analysis of calvarial bone defects in rats using microcomputed tomography: potential for a novel composite material and a new quantitative measurement

Reconstruction of craniomaxillofacial defects is a challenge for surgeons and has psychological and functional burdens for patients. Undoubtedly, there is a need for improved biomaterials and techniques for craniomaxillofacial reconstruction.     

Evaluation of the trueness and precision of eight extraoral laboratory scanners with a complete-arch model: a three-dimensional analysis

PurposeThe purpose of this study was to evaluate the trueness and precision of eight different extraoral laboratory scanners using three-dimensional (3D) analysis method.MethodAn arch-shaped master model was designed with a computer software (Rapidform XOR2) and manufactured with a 3D printer (Projet 3510 MP). Then the master model was digitized with an industrial 3D scanner (ATOS Core 200). With each scanner master model was scanned ten times and stereolithography (.stl) data were imported into 3D analysis software (Geomagic Control). Accuracy was determined with evaluating trueness and precision.ResultsTrueness of the scanners were 27.5 μm for 7 series; 30.9 μm for D640; 26.8 μm for D710; 33.3 μm for Activity 102; 32.4 μm for Tizian Smart-Scan; 21.6 μm for NeWay; 26.1 μm for inEOS X5 and 17,47 μm for D2000. 28.2 μm for laser; 32.9 μm for white light and 21.7 μm for blue light scanners. Significant differences were found between scanners (p < .001), (p < .001). Precision of the scanners were 30.1 μm for 7 series; 31.7 μm for D640; 26.3 μm for D710; 22.7 μm for Activity 102; 25.1 μm for Tizian Smart-Scan; 15.7 μm for NeWay; 26.1 μm for inEOS X5; 16.6 μm for D2000. 29.2 μm for laser; 24.4 μm for white light and 19.2 μm for blue light scanners. Significant differences were found between scanners (p < .001), (p = .027).ConclusionsThe systems that had the best combination of trueness and precision for complete-arch scanning were D2000 and NeWay. Scanners using blue-light showed more accurate results than the white-light and laser scanners.     

恒牙牙冠与牙根长度发育完成时间及性别差异探讨

目的 确定不同恒牙(除第三磨牙外)的牙冠与牙根长度的发育完成时间,探讨牙冠与牙根长度发育完成时间的性别差异。方法 选择3304例3~18岁儿童与青少年全口曲面体层片,应用Haavikko法分别记录每个恒牙的发育分期,采用SPSS 25.0软件包计算男女不同恒牙的牙冠与牙根长度发育完成时间的中位数,利用Mann-whitney U检验进行男女性别间差异比较。结果 中切牙和第一磨牙的牙冠发育完成时间无性别差异,P值分别为0.143(上颌中切牙)、0.122(上颌第一磨牙)、0.191(下颌中切牙)和0.558(下颌第一磨牙),其余牙女性均显著早于男性。上颌中、侧切牙、第二前磨牙和第二磨牙的牙根长度发育完成时间无性别差异,P值分别为0.057、0.130和0.294;下颌中,第二前磨牙和第二磨牙的牙根长度发育完成时间无性别差异,P值分别为0.428、0.057;上、下颌其余牙牙根长度发育完成时间女性均显著早于男性。结论 恒牙牙冠与牙根长度发育完成时间女性普遍早于男性,上、下颌恒牙牙冠与牙根长度发育完成时间的性别差异相似。