传统及数字化口腔种植导板的制作及临床应用研究进展

随着口腔种植手术的广泛开展,种植导板在术中的应用不仅有助于术前诊疗计划的设计,还有助于种植体在牙槽骨中的正确定位、成角优化,从而最终达到兼顾功能和美学的术后效果。以修复为导向设计种植导板应用于临床,可相对降低并发症发生的风险。随着椎形束CT(CBCT)的广泛应用,国内外学者在传统种植导板的基础上,结合数字化技术,完成了各种改良式种植导板的制作,由此推进了种植导板的发展。该文对常用的口腔种植导板的分类、优缺点以及计算机辅助外科种植导板进行综述,为临床中种植导板的应用提供参考。     

The evolution of craniofacial resection: A new workflow for virtual planning in complex craniofacial procedures

Complex craniofacial surgery has been later to take advantage of computerized planning than traditional maxillofacial procedures. Virtual reality, 3D model navigation, and bioengineering analyses have changed our approach to the surgical planning of craniofacial resection, increasing the benefits of surgery in terms of accuracy while decreasing complication rate.This study introduces a new workflow for 3D reconstruction, virtual model navigation, and alignment analyses, and demonstrates its successful application in a sample of four patients. A case of squamous cell carcinoma of the maxillary and ethmoid sinus in a 62-year-old patient is presented to evaluate the application of the workflow for a combined transfacial and transcranial resection. Results demonstrate that virtual surgical planning was successfully translated into navigational coordinates and reproduced in the operating room.While the literature provides a wide range of applications of virtual planning for traditional maxillofacial procedures, its introduction for complex craniofacial procedures remains difficult. The presented case shows that it is worth investigating the correlation between virtual reality planning and surgical accuracy for craniofacial resection, and related advantages in terms of surgical safety and improved prognosis.     

Accuracy of Different Imaging CBCT Systems for the Detection of Natural External Radicular Resorption Cavities: An Ex Vivo Study

ObjectiveThe aim of this study was to compare the sensitivity and specificity of 3 different systems of cone-beam computed tomography (CBCT) in the detection of natural external root resorption (ERR) cavities using microtomography as the gold standard.MethodA sample of 126 ex vivo teeth were submitted to a microtomography examination to verify the presence/absence of ERR cavities. Then, they were divided into the control group: 85 teeth that did not present with an ERR cavity; and experimental group: 41 teeth that presented with 1 or more ERR cavities. The size of the natural ERR cavities varied from 2.46 mm³ to 3.11 mm³, which corresponded to cavities of 1.67 mm and 1.81 mm in diameter, respectively. The teeth were placed on a dry human mandible for scanning in each of the 3 protocols with different voxel sizes: 0.25 mm, 0.20 mm, and 0.166 mm.ResultsThe accuracy of the 3 protocols evaluated in this study are listed in decreasing order: 60.3% for a voxel size of 0.20 mm, 56.7% for a voxel size of 0.166 mm, and 46.7% for a voxel size of 0.25 mm; these are smaller values than previous studies have obtained using artificial ERR cavities. Statistically significant results were not found among the 3 CBCT protocols that were used (P > .05), and the receiver operating characteristic curve shows the small differences found between the protocols.ConclusionThe results indicate that CBCT presents, for natural ERR, lower sensitivity and specificity values than those detected in previous studies of artificial cavities. The results demonstrate that natural ERR is neither easily observed nor accurately located by CBCT, as previous studies using artificial ERR indicated.     

以苄索氯胺和异丙醇为主要有效成分的消毒剂对牙科印模精度的影响

目的:探究以苄素氯胺和异丙醇为主要有效成分的消毒剂(Cavicide)对于牙科印模精度的影响。方法:体外试验评价Cavicide消毒剂对藻酸盐、聚醚橡胶和硅橡胶3种印模材料消毒后对印模精度的影响。应用高精度模型扫描仪(IScan D103i, Imetric)将标准模型数字化,使用藻酸盐、聚醚橡胶和硅橡胶材料分别制取标准模型的印模各30个,并将每种印模材料的30个印模随机平均分为3组,每组10个印模。在印模制取完成后,3组分别采用仅清水冲洗15 s(空白对照组,BC组)、2%(质量分数)戊二醛溶液浸泡30 min(戊二醛组,GD组)、Cavicide溶液表面喷洒5 min(Cavicide组,CC组)。采用模型扫描仪扫描印模,获得印模的数字化模型。在三维分析软件中,将印模扫描图像与标准模型的数字化模型进行配准,采用RMS作为评价印模与标准模型间偏差的参数。采用单因素方差分析比较3组间偏差,保存偏差的色谱图进行可视化分析。结果:聚醚橡胶及硅橡胶印模材料,3组间差异均无统计学意义(P=0.933,P=0.827);藻酸盐印模材料,GD组与BC组、GD组与CC组间差异均具有统计学意义(GD与 BC,P=0.001,GD与CC,P=0.002), BC组与CC组间差异无统计学意义(P=0.854)。结论:Cavicide喷洒消毒对聚醚橡胶、硅橡胶和藻酸盐印模的精度均未见影响。     

胸片对胸部疾病诊断作用:附496例影像与病理对照

目的 估价在CT、MR时代胸片对胸部疾病诊断价值。方法 496例无选择胸外科手术病理证实胸部疾病，分别统计胸片与胸部CT术前诊断正确率和误诊率。结果 肺癌339例、肺结核33例、肺炎63例、错构瘤17例、肺囊肿10例、肺隔离症5例、其他29例。肺结核与肺炎诊断正确率分别为75．6％与62％，CT分别为78．8％及60％，二者诊断正确率差别较小。中央型肺癌与周围型肺癌胸片诊断正确率分别为80．2％及85％，CT分别为88．7％及93．1％，肺腺癌与细支气管肺泡癌CT诊断正确率明显高于胸片，分别为89．6％及91．3％，胸片为79．4％及69．6％。结论 本组材料表现81％的疾病胸片诊断有价值，在实际工作中胸片应为首选检查方法。     

Accuracy of self-reported anthropometric measures — Findings from the Finnish Twin Study

ObjectiveTo determine the accuracy of self-reported height, weight, body mass index (BMI) and waist circumference (WC) compared to the measured values, and to assess the similarity between self-reported and measured values within dizygotic (DZ) and monozygotic (MZ) twin pairs.MethodsThe data on self-reported and measured height, weight and WC values as well as measured hip circumference (HC) were collected from 444 twin individuals (53–67 years old, 60% women). Accuracies between self-reported and measured values were assessed by Pearson’s correlation coefficients, Cohen’s kappa coefficients and Bland-Altman 95% limits of agreement. Intra-class correlation was used in within-pair analyses.ResultsThe correlations between self-reported and measured values were high for all variables (r = 0.86–0.98), although the agreement assessed by Bland-Altman 95% limits had relatively wide variation. The degree of overestimating height was similar in both sexes, whereas women tended to underestimate and men overestimate their weight. Cohen’s kappa coefficients between self-reported and measured BMI categories were high: 0.71 in men and 0.70 in women. Further, the mean self-reported WC was less than the mean measured WC (difference in men 2.5 cm and women 2.6 cm). The within-pair correlations indicated a tendency of MZ co-twins to report anthropometric measures more similarly than DZ co-twins.ConclusionsSelf-reported anthropometric measures are reasonably accurate indicators for obesity in large cohort studies. However, the possibility of more similar reporting among MZ pairs should be taken into account in twin studies exploring the heritability of different phenotypes.     

基于最短曲面距离对3dMD立体摄影系统测量精度和稳定性的研究

目的：利用最短曲面距离验证3dMD立体摄影系统测量的精度和稳定性,对3dMD立体摄影系统的测量精度进行更为客观的评价。方法：被测物是表面贴有坐标格的直径14 cm的圆柱体模型,用3dMD立体摄影系统获取模型的表面数据,并利用该系统的测量工具测量模型上42个曲面距离,分别与对应的标准值进行统计学分析。结果：横向2格组、横向5格组、横向7格组和竖向7格组的测量值与标准值之间的差异有统计学意义（P<0．05）;竖向2格组、竖向5格组的差异无统计学意义（P>0．05）,但各组的误差均值都不超过0．3 mm;描述统计分析得出6组特征曲线长度的标准差均<0．1 mm,各测量组四分位数间距均≤0．15 mm。结论：3dMD立体摄影系统在测量曲面距离时精度高,稳定性好。     

The accuracy of statistical estimates in genetic studies of aging can be significantly improved

The sample size of the data used in genetic studies is often a factor limiting the accuracy of statistical estimates. In this paper we suggest a new approach to evaluation of genetic influence on risk of development of aging-related health disorders. The approach results in substantial improvement of the accuracy of statistical estimates without an increase in the size of the genetic sample. The approach is based on the joint analysis of data from the genetic samples and easily accessible non-genetic data, such as data collected in epidemiological, demographic, and longitudinal studies of human aging and aging-related pathologies.     

阴道镜下活检诊断CIN的准确性及其漏诊宫颈癌的相关因素分析

目的:探讨阴道镜下活检诊断宫颈上皮内瘤样病变(CIN)的准确性及其漏诊宫颈癌的相关因素。方法:回顾性分析经阴道镜下活检确诊的118例CIN患者临床资料,均行宫颈环形电切术(LEEP),以术后病理为金标准,观察CIN的准确性,分析漏诊相关因素。结果:1118例患者阴道镜下活检与LEEP术后病理检查符合率为85.59%,病理级别上升23例(19.49%),其中漏诊浸润癌17例(14.41%);2年龄≥50岁、细胞学检测HSIL、阴道镜病理CINⅠ级、阴道镜图像不满意、活检标本1个、宫颈病变面积1/2者宫颈癌漏诊率高(均P0.05),细胞学检测HSIL、阴道镜图像质量、活检标本个数、宫颈病变面积是影响阴道镜下活检漏诊宫颈癌的关键因素(P0.05)。结论:阴道镜对宫颈病变具有直观性,但对CIN的诊断尚不够准确,强化对宫颈细胞学的鉴别,提高阴道镜的操作技能,改进图像质量,尤其是多点取活检是降低宫颈癌漏诊率的关键。