Maxillary third molars with horizontal impaction: A cross-sectional study using computed tomography in young Japanese patients

ObjectiveTo examine the anatomical characteristics of impacted maxillary third molars to help predict and prevent possible adverse events during extraction.MethodsThis retrospective study enrolled young Japanese patients that were assessed for third molar extraction. Patients with maxillary third molar impaction presenting with no space between the maxillary second molar and the occlusal surface of the maxillary third molar were analysed using computed tomography data.ResultsIn this study, a total of 663 patients aged 20–29 years were examined for third molar extraction and 26 teeth in 23 patients were analysed. The mean ± SD angle between the second and third molar axes was 54.2° ± 7.5° and the mean ± SD length of the maxillary third molar was 16.1 ± 1.9 mm. The maxillary third molars showed close or extensive contact with the maxillary sinus and computed tomography did not show any bone from the maxillary sinus floor. Furthermore, in all patients, the crowns of the third molars were not completely covered by the alveolar bone.ConclusionsMaxillary third molars with horizontal impaction showed close or extensive contact with the maxillary sinus and their crowns were not completely covered by the alveolar bone.     

妊娠晚期危重型新型冠状病毒肺炎一例

本文报告一例妊娠晚期合并新型冠状病毒肺炎(COVID-19)危重型孕妇。患者32岁,孕35周+2因"咽痛4 d,发热3 h"入院。入院前曾至湖北孝感应城,回家隔离期间发病。入院后病情进展迅速,7 h后出现左侧胸背部疼痛、气促、头晕,迅即出现呼吸衰竭、感染性休克。考虑病情严重,且有2次剖宫产史,行紧急子宫下段剖宫产术。术前血气分析示呼吸衰竭、呼吸性酸中毒合并代谢性酸中毒。术中娩出一男婴,2700 g,1 min Apgar评分1分(心率20次/min),经复苏抢救,5和10 min评分均为1分,家属放弃抢救后死亡。产妇术后气管插管呼吸机维持,同时给予其他支持治疗。入院时的新型冠状病毒核酸检测结果于分娩后报告为阳性,遂转入定点医院治疗。患者术后26 d体外膜肺氧合脱机成功,术后36 d脱离呼吸机,进入康复阶段。     

龈沟内环形切口法用于下颌远中邻面暴露≥1/2的水平阻生第三磨牙拔除的研究

目的 探讨龈沟内环形切口法用于下颌远中邻面暴露≥1/2的水平阻生第三磨牙拔除的临床效果。方法 纳入2020年3月—2022年3月我院收治的180例需拔除下颌远中邻面暴露≥1/2的水平阻生第三磨牙的患者作为研究对象,采用随机数字表法分为观察组和对照组,每组90例。观察组采用龈沟内环形切口法,对照组采用标准封套法。比较两组术后2、7 d出血程度、疼痛程度、肿胀程度、最大开口度,术前与术后3个月下颌第二磨牙牙周探诊深度及并发症发生情况。结果 观察组术后2 d出血程度、疼痛程度、肿胀程度均轻于对照组（P＜0.05）,最大开口度大于对照组（P＜0.05）,两组术后7 d出血程度、疼痛程度、肿胀程度、最大开口度差异均无统计学意义（P＞0.05）;两组术后3个月下颌第二磨牙远颊位点、近颊位点、颊侧位点、远舌位点、近舌位点、舌侧位点牙周探诊深度较术前差异均无统计学意义（P＞0.05）,且两组组间差异无统计学意义（P＞0.05）;两组并发症总发生率差异无统计学意义（P＞0.05）。结论 下颌远中邻面暴露≥1/2的水平阻生第三磨牙拔除术中采用龈沟内环形切口法,可减轻术后早期出血、疼痛及开口受限,缩短软组织恢复时间     

Bending and Straightening of a Medium Carbon Steel Continuous Casting Slab with Low Temperature End Plastic Groove

The high temperature brittleness range of medium carbon microalloyed steel under an actual continuous casting process was determined by the high temperature tensile test. The test results revealed that only a third of the brittle temperature range from 650–825 °C was due to intergranular ferrite in the experimental steel. In addition, it was found that the plastic recovery was fast and stable when the temperature was lower than 725 °C (the lowest plastic temperature). Bending/straightening operation in this temperature range was conducive to controlling the generation of corner cracks. In order to keep the corner temperature at the low temperature end of the plastic curve when the slab was bent/straightened, the cooling water scheme of the secondary cooling zone of the continuous caster was formulated by numerical calculation. By appropriately increasing the cooling water flow in the foot roll and the secondary cooling zones 1–5, the corner temperature of slab during bending operation was 600–700 °C, avoiding the brittle temperature range. The industrial test was then carried out. The results showed that after using the optimized water volume, the corner grains of the slab were uniform and the microstructure was mainly pearlite + ferrite. In addition, the abnormally large grain size was reduced, and a large amount of ferrite was generated inside the grain, which avoided stress concentration at the corner of the slab during bending/straightening operation, and basically eliminated the corner crack of the slab.     

医学高校图书馆提供第三空间为社会服务的价值研究

介绍第三空间的概念,讨论医学高校图书馆利用自身的环境、资源和人才等,开设第三空间为社会服务的优势,从满足更多区域医务及社会大众医学知识需求、新型休闲娱乐需求、增进社会和谐、展示自我价值需求和健康生活新风尚等方面,具体阐述现时期医学高校图书馆进行第三空间对外服务的社会意义。     

下颌阻生第三磨牙与下颌管关系分型的研究

目的:探讨下颌阻生第三磨牙与下颌管密切关系的系统分型.方法:3237例下颌阻生第三磨牙的曲面体层X线摄像,其中296例阻生牙牙根与下颌管关系密切(间距≤1 mm)增摄CBCT检查,结合临床资料进行分析.结果:下颌阻生第三磨牙与下颌管密切关系有根侧型30.40％、邻管型50.33％、入管型4.72％、卧管型13.51％、...     

第三腰椎横突综合征患者的肌骨超声表现及与Oswestry功能障碍指数的相关性分析

目的分析第三腰椎横突综合征患者的肌骨超声表现及与Oswestry功能障碍指数(ODI)的相关性。方法回顾性分析2019年1月—2021年2月在河北省中医院就诊的121例第三腰椎横突综合征患者的临床资料(观察组),另取同期该院健康体检者50例作为对照组。治疗前后采用肌骨超声对患者进行检查;并采用ODI评价患者腰椎功能,分析肌骨超声表现与ODI评分的相关性。结果治疗前,观察组肌骨超声评分、ODI评分高于对照组(P <0.05);治疗后观察组患者肌骨超声评分、ODI评分降低(P <0.05)。观察组治疗前后肌骨超声评分与ODI评分均呈正相关(r=0.735和0.681,P=0.009和0.018)。观察组治疗前后血清IL-6、IL-10、TNF-α水平均高于对照组(P <0.05);治疗后观察组血清IL-6、IL-10、TNF-α水平低于治疗前(P <0.05)。逐步多因素Logistic回归分析结果表明,肌骨超声评分[■=1.881(95%CI:1.239,2.856)]、ODI评分[■=1.848(95%CI:1.246,2.740)]、IL-6 [■=1.818...     

经前纵裂胼胝体入路切除第三脑室前、中、后部肿瘤简

目的探讨经前纵裂胼胝体入路切除第三脑室前、中、后部肿瘤的可行性和优势。方法回顾性分析153例第三脑室肿瘤病人的临床资料。病人均经前纵裂胼胝体人路行显微手术,术中行第三脑室底造瘘。术前MRI示肿瘤位于第三脑室前部68例（44．4％）,第三脑室中部36例（23．5％）,第三脑室后部49例（32．0％）。结果术后MRI证实手术全切123例（80．4％）．大部切除26例（17．0％）,部分切除4例（2．6％）。术后并发症：神经功能障碍45例（29．4％）,脑室内出血13例（8．5％）,癫痫15例（9．8％）,脑积水14例（9．2％）。随访153例,时间3个月一5年。死亡15例,肿瘤复发或进展55例,其中2l例再次手术。结论经前纵裂胼胝体入路对第三脑室前、中、后部肿瘤暴露良好,可直视下切除肿瘤,手术全切率高。联合术中第三脑室底造瘘．术后并发症少。     

第三代头孢菌素引发消化道出血的机制分析

目的:阐述第三代头孢菌素引发消化道出血的可能机制.方法:对国内近30 a的相关文献进行综合回顾性分析.结果:第三代头孢菌素可导致多器官黏膜上皮的严重损害,表现为消化道黏膜损害并出血、呼吸道黏膜损害并出血,或尿道黏膜损害并出血;其他器官损害有心、肺、神经等.73例不良反应患者,消化道黏膜损害并出血6例,尿道黏膜损害并出血2例,呼吸道黏膜损害并出血1例.本组病例出血死亡率50%.结论:第三代头孢菌素导致多器官功能损害,其中引起消化道大出血发生率较其他不良反应发生率低,但死亡率较高,后果严重.