Influence of the Intracanal Material and Metal Artifact Reduction Tool in the Detection of the Second Mesiobuccal Canal in Cone-beam Computed Tomographic Examinations

IntroductionThe aim of this study was to evaluate the influence of different intracanal materials and the metallic artifact reduction (MAR) tool of cone-beam computed tomographic (CBCT) imaging on the detection of the second mesiobuccal (MB2) canal in maxillary first molars.MethodsForty maxillary first molars were selected; half of them had the MB2 canal in the mesiobuccal root confirmed by micro–computed tomographic imaging. All teeth were instrumented, except for the MB2 canal, and filled with gutta-percha, which was passively inserted up to the working length. Each tooth was individually inserted into a dry human skull, and CBCT scans were performed using the OP300 device (Instrumentarium Dental, Tuusula, Finland) with and without the use of the MAR tool. For each scanned tooth, the following intracanal materials were used in the palatal root: gutta-percha, silver palladium, nickel chromium, and cobalt chromium. Five examiners assessed the images for the detection of the MB2 canal using a 5-point scale. The weighted kappa test was applied to evaluate intra- and interexaminer reproducibility. The diagnostic values (sensitivity, specificity, and area under the receiver operating characteristic curve) were calculated in the different groups and compared using 2-way analysis of variance and the Tukey post hoc test.ResultsThe intra- and interobserver agreement ranges for the different conditions were studied. The diagnostic values were not significantly different (P > .05) regardless of the intracanal material and the use of the MAR tool.ConclusionsThe presence of different intracanal materials and MAR activation does not influence CBCT-based detection of MB2 canals.     

Prevalence of Apical Periodontitis and Conventional Nonsurgical Root Canal Treatment in General Adult Population: An Updated Systematic Review and Meta-analysis of Cross-sectional Studies Published between 2012 and 2020

IntroductionThis study aimed to summarize data on apical periodontitis (AP) and nonsurgical root canal treatment (NSRCT) prevalence and risk factors related to age, gender, and quality of restorative and endodontic treatment in the general population from cross-sectional studies published between 2012 and 2020.MethodsAn electronic search was performed in the following databases: Web of Science, Scopus, and PubMed. The conducted literature search covered studies published between 2012 and 2020, without restrictions on language. The STROBE and NOS tools were used for quality assessment of the included studies.ResultsSixteen articles were included in the review. In total, 200,041 teeth were examined. On average, 6.3% of teeth had AP, and 7.4% had NSRCT. Forty-one percent of RCT teeth had AP, and 3.5% of untreated teeth had AP. Female patients were less prone to AP in endodontically treated teeth only, compared with male patients (P < .001). Variable stratification of age subgroups among included studies prevented us from conducting a meta-analysis. An increase in AP frequency was found in teeth with inadequate restorative and endodontic treatment (P < .001 and P < .001, respectively). Because of high heterogeneity, these results should be taken with caution.ConclusionsThere is an increased AP prevalence in the adult general population compared with data from 2012 (6.3% versus 5.4%) in both endodontically treated (41.3% versus 35.9%) and untreated teeth (3.5% versus 2.1%). In addition, AP developed less frequently in female patients with endodontically treated teeth and in teeth with inadequate compared with adequate restorative and endodontic treatment.     

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.     

Biocompatibility and Bioactive Potential of New Calcium Silicate–based Endodontic Sealers: Bio-C Sealer and Sealer Plus BC

IntroductionBio-C Sealer (BC; Angelus, Londrina, PR, Brazil) and Sealer Plus BC (SPBC; MK Life, Porto Alegre, Brazil) are new ready-to-use bioceramic endodontic sealers. The aim of this study was to evaluate the biocompatibility and bioactive potential of BC and SPBC sealers in comparison with AH Plus (AHP; Dentsply DeTrey Gmbh, Konstanz, Germany) in subcutaneous tissue of rats.MethodsPolyethylene tubes filled with materials and empty tubes, serving as the control group, were implanted in the subcutaneous tissues of rats. After 7, 15, 30, and 60 days, the tubes with connective tissue were removed, and inflammatory cells (ICs)/mm² and immunolabeled cells for interleukin (IL)-6 were evaluated. Osteocalcin and von Kossa analysis were also performed. Data were submitted to analysis of variance and Tukey tests, with a significance level of 5%.ResultsAt 7 days, SPBC showed lower ICs than BC (P < .05). AHP exhibited greater immunolabeled cells for IL-6 (P < .05). After 15 days, BC showed lower ICs and IL-6 compared with other materials. At 30 days, SPBC and AHP showed higher values for ICs (P < .05). After 60 days, calcium silicate sealers did not show statistical difference (P > .05) for ICs and IL-6, with values lower than AHP (P < .05). The materials showed positive structures to von Kossa staining. BC exhibited osteocalcin labeling in all periods. SPBC showed osteocalcin labeling from 15–60 days. AHP and the control group did not exhibit osteocalcin labeling.ConclusionsBC and SPBC sealers are biocompatible and present bioactive potential.     

超声引导下双侧多点竖脊肌平面阻滞在后路脊柱侧凸矫正融合术中的应用

目的:探讨超声引导下双侧多点竖脊肌平面阻滞（ESPB）在后路脊柱侧凸矫正全麻手术中的应用和对术后镇痛的影响。方法:选取择期后路脊柱侧凸矫正融合术患者40例，ASA分级Ⅰ~Ⅱ，按照随机数字表法将所有患者分为ESPB组（E组）和对照组（C组），每组20例。E组于全身麻醉诱导前30 min分别行双侧T5和T10水平的ESPB，C组注射等量生理盐水。注药20 min后使用针刺痛觉评估法监测感觉阻滞平面。两组患者均采用相同的麻醉诱导及麻醉维持方案，术中均采用Narcotrend监测麻醉镇静深度。术后均行舒芬太尼自控静脉镇痛。记录两组患者术中麻醉药物用量、术后苏醒时间、术后2、4、6、12、24 h静息视觉模拟评分（VAS评分）和24 h PCA镇痛泵舒芬太尼用量及PCA按压次数；相关不良反应（恶心呕吐、呼吸抑制）以及阻滞相关并发症（穿刺部位感染、血肿、局麻药中毒）。结果:E组患者术中麻醉药物用量、苏醒时间、术后2、4、6、12 h VAS评分和PCA舒芬太尼用量及PCA按压次数均低于C组（P<0.05）。但术后24 h VAS评分两组比较差异无统计学意义。E组未出现穿刺部位感染、血肿、局麻药中毒等并发症。结论:超声引导下双侧多点ESPB在后路脊柱侧凸矫正融合术中能提供良好的镇痛，可以缩短麻醉苏醒时间，降低围术期阿片类药物的使用。     

醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响

目的　探究醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响。方法　Wistar大鼠36只，随机分为对照组、模型组、转染组，后两组建立糖尿病大鼠模型。模型建立成功后，构建含有晚期糖基化终末产物受体siRNA的质粒并利用慢病毒转染入转染组大鼠体内。造模后4周、8周、12周，记录各组大鼠体质量及空腹血糖。造模后9周，禁食6 h，测定口服葡萄糖耐量。造模后12周，处死全部大鼠后，TUNEL法检测各组大鼠视网膜神经元凋亡情况，荧光分光光度计测定醛糖还原酶活性，Western blotting法测定晚期糖基化终末产物受体的表达，RT-PCR检测视网膜中Bcl-2和Bax mRNA相对表达量。结果　造模后4周、8周、12周，转染组和模型组的大鼠体质量均低于对照组（均为P<0.05）；造模后12周，转染组大鼠体质量高于模型组（P<0.05）。造模后4周、8周、12周，各组内大鼠空腹血糖水平均无明显变化（均为P>0.05），转染组和模型组大鼠的空腹血糖水平均高于对照组（均为P<0.05）。模型组和转染组大鼠在口服葡萄糖后30 min时，血糖水平均高于对照组（均为P<0.05）；在120 min时分别下降至最低，但仍高于对照组（均为P<0.05）。模型组和转染组的视网膜神经元凋亡指数、醛糖还原酶活性、晚期糖基化终末产物受体和Bax mRNA相对表达量均高于对照组（均为P<0.05），且转染组均高于模型组（均为P<0.05）。模型组和转染组的Bcl-2 mRNA相对表达量均低于对照组（均为P<0.05），转染组低于模型组（P<0.05）。结论　晚期糖基化终末产物结合受体后产生大量的氧自由基损伤，可能是导致糖尿病视网膜神经元凋亡，进而导致糖尿病视网膜病变发生的机制之一。