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1.
《Dental materials》2022,38(9):1459-1469
ObjectiveTo evaluate the manufacturing accuracy of zirconia four-unit fixed dental prostheses (FDPs) fabricated by three different additive manufacturing technologies compared with subtractive manufacturing.MethodsA total of 79 zirconia FDPs were produced by three different manufacturing technologies, representing additive (one stereolithography [aSLA] and one material jetting [aMJ] device, two digital light processing [aDLP1/aDLP2] devices) and subtractive manufacturing (two devices [s1/s2]), the latter serving as references. After printing, additively manufactured FDPs were debound and finally sintered. Subsequently, samples were circumferentially digitized and acquired surface areas were split in three Regions Of Interest (ROIs: inner/outer shell, margin). Design and acquired data were compared for accuracy using an inspection software. Statistical evaluation was performed using the root mean square error (RMSE) and nonparametric Kruskal-Wallis method with post hoc Wilcoxon-Mann-Whitney U tests. Bonferroni correction was applied in case of multiple testing.ResultsRegardless the ROI, significant differences were observed between manufacturing technologies (P < 0.001). Subtractive manufacturing was the most accurate with no significant difference regarding the material/device (s1/s2, P > 0.054). Likewise, no statistical difference regarding accurary was found when comparing s2 with aMJ and aSLA in most ROIs (P > 0.085). In general, mean surface deviation was< 50 µm for s1/s2 and aMJ and< 100 µm for aSLA and aDLP2. aDLP1 showed surface deviations> 100 µm and was the least accurate compared to the other additive/subtractive technologies.SignificanceAdditive manufacturing represents a promising set of technologies for the manufacturing of zirconia FDPs, but not yet as accurate as subtractive manufacturing. Methodological impact on accuracy within and in between different additive technologies needs to be further investigated. 相似文献
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3.
《Saudi Dental Journal》2022,34(2):142-149
ObjectiveTo study the accuracy and precision of estimating the prevalence, extent and associated risks of untreated periodontitis using partial-mouth recording protocols (PRPs) Methods: A purposive sample of 431 individuals who had never been treated for periodontal disease was recruited from screening clinics at the King Saud bin Abdul-Aziz University for Health Sciences. Data were collected using questionnaires and clinical examinations. The prevalence, extent and risk associations of periodontitis were evaluated. Three PRPs were compared to full-mouth recordings (FRPs) in terms of the sensitivity, specificity, predictive values, and absolute bias. Results: The prevalence of periodontitis was estimated with the highest accuracy and precision by examinations of the full mouth at the mesiobuccal and distolingual sites (FM)MB-DL, followed by random half-mouth (RHM) recordings. The extent of periodontitis was estimated with high precision using all the PRPs, and the absolute bias ranged from ?0.6 to ?2.3. The absolute bias indicated by OR for risk associations was small for the three PRPs and ranged from ?0.8 to 0.8. Conclusion: (FM)MB-DL and RHM were the PRPs with moderate to high levels of accuracy and precision for estimating the prevalence and risk associations of periodontitis. The extent of periodontitis was estimated with high precision using all three PRPs. The results of this study showed that the magnitude and direction of bias were associated with the severity of periodontitis, the selected PRPs and the magnitude of the risk associations. 相似文献
4.
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。 相似文献
5.
目的 探讨基于智能手机简易增强现实技术定位幕上高血压性脑内血肿的可靠性和准确性。方法 回顾性分析2017年10月至2018年10月微创手术治疗的42例幕上高血压性脑出血的临床资料。术前将急诊头颅CT扫描数据以DICOM形式通过医学影像存档与通信系统导入工作电脑,应用3D Slicer软件行脑内血肿及头面部皮肤三维重建,设置参考点后将图像导入智能手机,通过手机相机功能实现简易增强现实技术,描画脑内血肿体表投影后,在血肿边缘粘贴标记物后复查头颅CT,分析各标记点与血肿实际边界的距离偏差。结果 42例共粘贴标记物168个。标记物与血肿距离偏差在0.04~7.20 mm,平均(3.10±1.10)mm;上缘、下缘、前缘、后缘的距离分别为(2.90±1.19)mm、(3.02±1.31)mm、(2.66±1.27)mm、(2.43±1.41)mm。头皮标记物与脑内深部血肿实际上缘、下缘、前缘、后缘的距离偏差无统计学差异(P>0.05)。结论 简易增强现实技术可为幕上高血压性脑内血肿微创手术提供可靠及较准确的体表定位指导,可作为脑内血肿定位参考指标。 相似文献
6.
目的 探讨品管圈在脑室引流患者引流瓶高度设置准确率的应用效果。方法 2016年9月至2017年3月,宿迁市第一人民医院重症医学科按照品管圈十大步骤进行操作,调查脑室引流患者引流瓶高度设置不准确的原因,制定对策并实施。结果 脑室引流患者引流瓶高度设置准确率由品管圈活动实施前的45%提高至实施后的76%(P﹤0.001)。圈员能力也得到提高。结论 品管圈活动能够提高脑室引流患者引流瓶高度设置的准确率,同时在活动过程中增强了护士的综合能力。 相似文献
7.
Yangyang R. Yu Eric H. Rosenfeld Shaahin Dadjoo Robert C. Orth Monica E. Lopez Sohail R. Shah Bindi J. Naik-Mathuria 《Journal of pediatric surgery》2019,54(11):2274-2278
PurposeClinical prediction of disease severity is important as one considers nonoperative management of simple appendicitis. This study assesses the accuracy of surgeons' prediction of appendicitis severity.MethodsFrom February to August 2016, pediatric surgeons at a single institution were asked to predict whether patients had simple or complex appendicitis preoperatively based on clinical data, imaging, and general assessment. Receiver operating characteristic curves were generated to determine area under the curve (AUC) and optimal cutoff points of clinical findings for diagnosing simple appendicitis. Outcomes included sensitivity and specificity of variables to identify simple appendicitis. Predictions were compared to operative findings using χ2. A p-value < 0.05 was considered statistically significant.ResultsOf 125 cases (median age 9 years [IQR 7–13], 58% male), simple appendicitis was predicted in 77 (62%) and complex appendicitis in 48 (38%). Predictions were accurate in 59 (77%) simple cases and 45 (94%) complex cases. Although surgeon prediction was more accurate than individual imaging or clinical findings and was highly sensitive (95%) for diagnosing simple appendicitis, specificity was only 71%.Lower WBC (< 15.5 × 103/μL, AUC 0.61, p = 0.05), afebrile (< 100.4 °F, AUC 0.86, p < 0.01), and shorter symptom duration (≤ 1.5 days, AUC 0.71, p < 0.001) were associated with simple appendicitis. Of 18 complex cases (14%) inaccurately predicted as simple, 17 (94%) lacked diffuse tenderness, 15 (83%) were well-appearing, 11 (61%) had ultrasound findings of simple appendicitis, 11 (61%) had ≤ 2 days of symptoms, and 8 (44%) were afebrile (< 100.4 °F).ConclusionWhile surgeon prediction of simple appendicitis is more accurate than ultrasound or clinical data alone, diagnostic accuracy is still limited.Type of studyProspective survey.Level of evidenceII 相似文献
8.
《Allergology international》2019,68(2):191-198
BackgroundWe obtain summary estimates of the accuracy of additional objective tests for the diagnosis of adult asthma using systematic review and meta-analysis of diagnostic test accuracy studies.MethodsMedline, Embase, and other relevant electronic databases were searched for papers published between January 1989 and December 2016. Studies were included if they evaluated the diagnostic accuracy of objective tests, including airway reversibility (AR), airway hyperresponsiveness (AHR), and fractionated exhaled nitric oxide (FeNO) for the diagnosis of adult asthma in patients with symptoms suggestive of asthma. If papers were assessed appropriate using the adapted QUADAS-2 tool, meta-analysis was conducted using the hierarchical bivariate model. This hierarchical model accounts for both within and between study variability.ResultsSixteen studies reported the performance of the evaluated objective tests at presentation. For diagnosis of adult asthma, overall sensitivity and specificity for AR were 0.39 (95% confidence interval [CI] 0.18 to 0.66) and 0.95 (95% CI 0.86 to 1.00); for AHR, 0.86 (95% CI 0.61 to 1.00) and 0.95 (95% CI 0.77 to 1.00); for FeNO, 0.65 (95% CI 0.53 to 0.77) and 0.83 (95% CI 0.75 to 0.90). Comprehensive comparison of three diagnostic tools for adult asthma using the back-calculated likelihood rate (LR) showed that AR and AHR corresponded to a higher LR+, and AHR gave a lower LR-.ConclusionsIn the current situation of no gold standard for diagnosis of adult asthma, AR and AHR are appropriate for ruling-in the true diagnosis, and AHR is superior for ruling-out a diagnosis. Since each objective test had a specific characteristic, it should be chosen depending on the situation, such as the capacity of the institution and the conditions of patients. 相似文献
9.
Teja S. Polisetty Gagan Grewal Jennifer Kurowicki Jacob J. Triplet Shanell Disla Jonathan C. Levy 《Seminars in Arthroplasty》2022,32(1):125-131
IntroductionVirtual planning for shoulder arthroplasty using preoperative computed tomography (CT) has been gaining popularity, and it is imperative for surgeons to recognize any differences in measurements that may exist amongst software platforms. The purpose of this study is to compare measurements of glenoid version, inclination, and humeral head subluxation between a manual approach and two varying automated software platforms using either a best-fit sphere technique (Wright-Medical BLUEPRINT) or an anatomic landmarks technique (Materalise SurgiCase).MethodsA case control study of 289 CT images from patients preoperatively planned for a total shoulder arthroplasty or reverse shoulder arthroplasty using SurgiCase (v3.0.110.5) were also successfully analyzed by BLUEPRINT (v2.1.6). Glenoid version, inclination, and subluxation were measured manually in a blind fashion by two separate investigators using axial and coronal images oriented to the scapular plane; interobserver and intraobserver reliabilities were measured using intraclass correlation coefficients (ICCs). Concordance correlation coefficients (CCCs), mean differences, and clinically relevant agreement in measurements between the software platforms and with the manual technique were compared. The impact of greater glenoid retroversion on the differences in measurements between the software platforms was further studied by correlation analysis.ResultsThe mean differences between SurgiCase and BLUEPRINT were + 0.5° for glenoid inclination (P = .064; CCC = 0.84), -0.9° for glenoid version (P < .001; CCC = 0.92), and -1.4% for humeral subluxation (P = .002; CCC = 0.88). Agreement within 5 units was 78.9% for inclination, 89.3% for version, and 64.1% for subluxation. Glenoid retroversion had no relation with the degree of variation in measured inclination (P = .59) or version (P = .56). There were significant differences between manual and 3D software measurements for glenoid inclination, version, and subluxation (P < .001). Both software measurements were more inferiorly inclined (average difference, SurgiCase -3.2° and BLUEPRINT -3.9°), more retroverted (average difference, SurgiCase -4.0° and BLUEPRINT -3.2°), and more posteriorly subluxated (average difference, SurgiCase + 3.4% and BLUEPRINT + 4.8%).ConclusionThe SurgiCase and BLUEPRINT preoperative planning software yield clinically similar measurements for glenoid version, inclination, and subluxation. The degree of glenoid retroversion does not impact the variability of inclination or version between the landmark and best-fit sphere software techniques. Compared to the 2D manual technique, both 3D software programs reported greater inferior inclination, retroversion, and posterior subluxation.Level of evidenceLevel III; Retrospective Diagnostic Study 相似文献
10.
省、市、县三级实验室分别采用镜检法、胶体金法及巢式PCR法对泰安市2015-2019年输入性疟疾进行诊断与复核。共诊断与复核输入性疟疾病例122例,其中镜检法和胶体金法的符合率分别为94.3%(115/122)和95.9%(117/122),镜检阴性率为5.7%(7/122),均为恶性疟;胶体金法阴性率为4.1%(5/122),3例非恶性疟和2例恶性疟阴性,3种检验方法符合率差异有统计学意义(P <0.05)。其中恶性疟和间日疟诊断符合率最高,均达100%,对卵形疟诊断符合率最低,仅为12/18,对4种疟原虫实验室诊断符合率差异有统计学意义(P <0.01)。医疗机构中初诊合格率为94.3%(115/122),市、县级疾病预防控制机构复核合格率分别为97.5%(119/122)和95.1%(116/122),差异无统计学意义(P> 0.05)。今后应继续加强市、县级疟疾实验室镜检人员技能培训,积极开展疟疾核酸检测,以进一步提升医疗及疾病预防控制机构的疟疾诊断水平。 相似文献