Cleaning,Shaping, and Disinfecting Abilities of 2 Instrument Systems as Evaluated by a Correlative Micro–computed Tomographic and Histobacteriologic Approach

IntroductionThis study assessed the cleaning, shaping, and disinfection abilities of 2 instrumentation systems in molar root canals using a novel correlative analytical approach.MethodsThe root canals from extracted mandibular and maxillary molars with apical periodontitis were pair matched according to anatomic similarities as determined by micro–computed tomographic analysis and prepared with either XP-endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) (n = 16) or Reciproc Blue (VDW, Munich, Germany) (n = 16) instruments and 2.5% sodium hypochlorite irrigation. Pre- and postpreparation micro–computed tomographic scans were used to identify and calculate the unprepared surface areas (shaping), which were histobacteriologically evaluated for the presence of residual bacteria (disinfection) and pulp tissue remnants (cleaning) in each canal third.ResultsUnprepared canal surface areas for XP-endo Shaper and Reciproc Blue in the full canal length were approximately 26% and 19% (P < .05), respectively (30% and 23% in the apical part of the canal, P > .05). Preparation with Reciproc Blue resulted in 37.5% canals free of bacteria in all sections examined and 56% in the apical sections only. XP-endo Shaper resulted in 44% canals free of bacteria in all sections, and 56% in the apical part of the canal only. Pulp tissue remnants were not observed in 31% (all canal sections) and 50% (apical canal sections) of specimens from both instrument systems. No significant differences were observed between instruments when comparing the amount of pulp tissue remnants and the number of cases negative for bacteria and tissue remnants (P > .05).ConclusionsAlthough the Reciproc Blue instrument had superior shaping ability in comparison with XP-endo Shaper, both systems performed similarly in cleaning and disinfecting root canals. Irregular canals and difficult-to-reach areas were not thoroughly cleaned and disinfected by any of the tested systems.     

Retrograde Instrumentation of Surgically Resected Roots Using Controlled Memory Files: A Human Cadaver Study

IntroductionThe purpose of this study is to evaluate the amount of residual obturation material of retroinstrumented surgically resected roots using controlled memory files and to evaluate the incidence of adverse treatment outcomes.MethodsThirty maxillary anterior teeth in human cadavers were selected, and nonsurgical root canal treatment was performed on these teeth. A standardized 4-mm osteotomy and a 3-mm root resection with as close to 0° bevel as possible were made on each tooth. A microsurgical diamond tip was used to create a 1- to 2-mm starting point for each retropreparation. A 25/06 and 30/06 VTaper 2H were bent at about 90° angle to mimic the clinical and anatomic restrictions and used to create a retropreparation to a depth of 14 mm. Micro–computed tomography scans were taken and analyzed for volume and percentage of residual obturation material at 5 and 10 mm. In addition, the incidences of instrument separation and crack and ledge formation in the teeth were recorded.ResultsThe median volume of residual obturation at 5 and 10 mm was 0.18 mm³ (interquartile range, 0.36 mm³) and 1.97 mm³ (interquartile range, 1.99 mm³), respectively. The overall incidence of file separation during retropreparation was 13.33% (4/30). Among the cases analyzed with micro–computed tomography, none showed crack or ledge formation.ConclusionsRetroinstrumentation of surgically resected roots using controlled memory files cleans the canal effectively with relatively low adverse treatment outcomes. Although this novel technique is limited in application, it is a safe and effective way to achieve a deep, clean retropreparation.     

Differentiating autoimmune pancreatitis from pancreatic ductal adenocarcinoma with CT radiomics features

PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.     

北京市养老机构老年人营养状况调查及其影响因素研究

背景　在人口老龄化日益加剧的社会背景之下，家庭养老功能不断减弱，机构养老成为今后发展的必然趋势。据报道，很多养老机构的老年人营养不合理，严重影响老年人的健康状况与生活质量。目的　通过调查北京市养老机构老年人营养现状及其影响因素，为全科医师营养教育及老年人生活质量提升提供理论依据。方法　2014年10月-2015年12月，采用方便整群抽样的方法，抽取了北京市7家养老机构，对符合纳入标准的老年人进行面对面问卷调查，问卷内容包括：一般情况、微型营养评定量表（MNA）、日常生活活动能力指数（BI）、老年人抑郁量表（GDS）。采用二元Logistic回归分析养老机构老年人营养状况的影响因素。结果　本研究共发放问卷258份，回收有效问卷258份，有效回收率为100%。被调查的258例老年人中，存在营养不良及存在营养不良发生风险的老年人共计75例（29.1%）。不同年龄、性别、婚姻状况、体质指数（BMI）、医疗费用支付方式、生活自理能力及精神状态的老年人营养状况比较，差异有统计学意义（P<0.05）。二元Logistic回归分析结果显示：年龄〔OR（95%CI）=2.349（1.070，5.156）〕、BMI〔OR（95%CI）=0.092（0.036，0.239）〕、医疗费用支付方式〔OR（95%CI）=0.208（0.083，0.522）〕、日常活动能力〔OR（95%CI）=10.214（3.099，33.669）〕、患病种数〔OR（95%CI）=2.682（1.248，5.763）〕及精神状态〔OR（95%CI）=4.822（2.005，11.600）〕是老年人营养状况的影响因素（P<0.05）。结论　北京地区养老机构的老年人面临着营养不良及营养不良发生风险的健康威胁，高龄、低BMI、抑郁、合并多种疾病、日常活动能力低下及无医保是其独立危险因素，需要对老年人加强个性化营养教育和营养治疗。     

一次性根管与常规根管治疗后冠修复对隐裂性牙髓炎患者的影响

目的 探讨一次性根管与常规根管治疗后冠修复对隐裂性牙髓炎患者的治疗效果。方法 选取2014年5月至2017年5月诊治的187例隐裂性牙髓炎患者随机分为观察组和对照组,观察组给予一次性根管治疗后冠修复,对照组给予常规根管治疗后冠修复,比较两组术前及术后1周Mohd Sulong疼痛分级、术后3个月临床疗效、术后6个月X线改变、术后2年治疗成功率。结果 术前两组Mohd Sulong疼痛分级无统计学差异(P＞0.05),冠修复术后1周两组疼痛分级无统计学差异(P＞0.05),术后3个月观察组临床疗效总有效率为97.83%较对照组88.41%显著提高(P＜0.05),术后6个月观察X线改变率为3.26%较对照组14.74%显著降低(P＜0.05),术后2年观察组治疗成功率为94.57%较对照组82.11%显著提高(P＜0.05)。结论 一次性根管治疗后冠修复能够缓解隐裂性牙髓炎疼痛,提高临床疗效,提高患者咀嚼功能和生活质量,值得在临床上推广。     

贵州省"5+3"模式订单定向医学毕业生的离职意愿及影响因素研究

背景 我国基层全科医生的离职意愿较高，调查其离职意愿并分析影响因素，可以为减少基层卫生人才流失提供思路。目前，完成"5+3"模式（5年临床医学本科教育+3年住院医师规范化培训）培养的订单定向医学毕业生逐步履约进入基层工作，而针对该部分全科医生离职意向的研究相对较少。 目的 调查贵州省"5+3"模式订单定向医学毕业生回归基层工作后的离职意愿及影响因素，为完善吸引卫生人才留任、建设基层全科医生队伍相关政策提供依据。 方法 以贵州省截至2020年底已完成"5+3"模式培养并履约到基层医疗卫生机构工作的2015—2017级订单定向医学毕业生为研究对象。于2021-01-20至2021-02-10对其开展电子问卷调查，内容包括毕业生的一般情况、职业满意度、离职意愿、服务期满后职业方向。共回收问卷347份，其中有效问卷311份，问卷有效回收率为89.6%。采用单因素分析及多元逐步线性回归分析全科医生离职意愿的影响因素。 结果 贵州省"5+3"订单定向医学毕业生的整体离职意愿得分为（3.98±0.98）分，具有离职倾向者229例（73.6%）。不同性别、单位地理位置、每日工作量者的离职意愿得分比较，差异有统计学意义（P<0.05）。多元逐步线性回归分析显示，单位负责人对待下属的方式、在工作中获得的成就感、对当前收入满意程度、家人对工作的支持程度、当地激励政策执行程度是"5+3"订单定向医学毕业生离职意愿的影响因素（P<0.05）。服务期满后，计划留任原基层医疗卫生机构者12例（3.9%），计划去其他基层医疗卫生机构者21例（6.7%），计划离开基层去上级医院工作者196例（63.0%），计划攻读全日制硕士学位者60例（19.3%）。 结论 贵州省"5+3"模式订单定向医学毕业生的离职意愿较高，预计服务期满后基层全科人才流失较多，需从提高收入、重视全科医生心理需求、优化全科医生培养与使用、发展基层医疗卫生机构、加强全科宣传等方面着手改善。