Regional distribution of interglobular dentine in human teeth

Interglobular dentine (IGD) is an area of poorly mineralized dentine matrix. It has been reported that there is an association between the retraction of odontoblast processes (OP) and the formation of IGD. A variation of the extent of OP has been described depending on the region of the tooth and age. This study aimed to find out the regional distribution of IGD in human teeth to observe any association between the extent of OP and the pattern of distribution of IGD.Ground sections were prepared from 52 extracted permanent teeth and the presence of IGD was observed in different regions of the crown and the root.The highest occurrence of IGD was found in the cervical and middle thirds followed by intercuspal, and coronal third in the crown. Statistical analysis of data depicted that the occurrence of IGD differed according to the region of the tooth. In roots, the highest occurrence of IGD was seen in the cervical third followed by the middle third.Previous reports have shown that OP extend up to the dentine–enamel junction in the coronal region and to the inner one-third of the cervical region. The varied pattern of distribution of IGD in the crown and root observed in our results corresponds to the above findings. Therefore, it is reasonable to surmise that there is an association between the distribution of IGD and the extent of OP. This allows us to confer that IGD tends to form in areas where OP do not extend to the dentine–enamel junction.     

三种不同修复方式修复根管治疗后前磨牙牙体缺损的临床研究

目的 探讨三种不同修复方式修复根管治疗后前磨牙牙体缺损的临床效果。方法 选取南安市第二医院口腔科2014年6月至2015年8月收治的符合纳入条件的83例行前磨牙根管治疗的患者(共计90颗患牙)进行研究,随机分为高嵌体修复组、全冠修复组、桩核冠修复组,每组各30 颗患牙。在修复后1年、2年、3年复诊,比较三种不同修复方式的修复效果。结果 高嵌体修复组、全冠修复组、桩核冠修复组在三年观察期结束时的修复优秀率分别为:92.9%、82.1%、85.2%;成功率分别为96.4%、92.9%、96.3%。各组的修复优秀率、成功率在各时间段比较差异均无统计学意义(P＞0.05)。结论 高嵌体、全冠、桩核冠用于根管治疗后前磨牙牙体缺损的修复均能取得较好的修复效果;高嵌体牙体预备量相对较少,能更多保留牙体组织,推荐使用。     

1例检验结果发布错误的根本原因分析

检验结果对临床治疗方案的选择起着至关重要的作用。通过1例检验结果发布错误事件,运用根本原因分析法,确认事件发生的根本原因,找到错误发生的系统因素,制定针对性改进措施,提升和完善系统,保障患者 安全。     

The Impact of Vaginal Laser Treatment for Genitourinary Syndrome of Menopause in Breast Cancer Survivors: A Systematic Review and Meta-analysis

IntroductionGenitourinary syndrome of menopause (GSM) is caused by hypo-estrogenism, resulting in vaginal dryness, pain, dyspareunia, and urinary tract infection. It is more severe and common in breast cancer (BC) survivors owing to the severity of induced menopause following treatment (ie, chemotherapy, GnRH agonists/anti-estrogen therapy). It has a detrimental effect on quality of life. The gold standard therapy is topical estrogen, which is highly effective; however, it is contraindicated in patients with BC owing to concerns with recurrence. Recently, vaginal laser therapy has been used to restore vaginal mucosal thickness, lubrication, and elasticity with good effect in menopausal women with GSM. The aim of this study is to assess the impact of vaginal laser therapy on BC-associated GSM.Materials and MethodsThis study is a systematic review and meta-analysis.ResultsA total of 48 papers were identified, revealing 10 observational studies of GSM symptoms before and after vaginal laser therapy with no randomized trials. Vaginal laser was effective in treating GSM in BC survivors with improvement in the Vaginal Health Index and the Visual Analogue Scale score for dyspareunia and vaginal dryness, sexual function, and overall satisfaction in the short term with minimal adverse events.ConclusionVaginal laser may be effective in treating GSM in BC survivors in the short term, but there are no long-term data on safety and efficacy. More research is needed looking at longer term follow-up, health economic costs, and sub-group analysis as well as the complex interplay between GSM and the other negative impacts of BC therapy on intimate relationships.     

同步辐射衍射增强CT应用于根管充填质量评价的实验研究

目的:观察同步辐射衍射增强CT对根管充填后离体牙的成像效果。方法:应用同步辐射衍射增强成像对10颗经根管预备和热牙胶充填的离体牙牙根进行成像,并进行CT重建。结果:可观察到主根管和侧支根管影像,并能清晰观察到根管充填后牙胶和根管封闭剂的充填区域,及充填缺陷如未被充填的空隙和气泡等情况。结论:同步辐射衍射增强CT适合观察和评价根管充填效果。     

PHMG根管封闭剂的制备及性能测定

目的:制备并筛选出符合ISO 6876:2001标准的聚六亚甲基单胍(PHMG)改性根管封闭剂,测定其物理性能和抑菌性能,以开发具有较强抑菌性能的新型根管封闭剂。方法:以氧化锌丁香油糊剂(ZOE)为对照,按照ISO 6876:2001规定的方法,测定不同PHMG浓度的根管封闭剂的物理性能;采用琼脂扩散法,测定其对粪肠球菌、白色念珠菌、大肠杆菌、金黄色葡萄球菌的抑菌性能;并进行统计学分析。结果:11组不同材料的流动性、固化时间、薄膜厚度和溶解率均符合ISO 6876:2001标准;固化后尺寸变化中以浓度为0.8%~2.0%的材料符合ISO 6876:2001标准。PHMG根管封闭剂的抑菌性显著高于氧化锌丁香油糊剂的抑菌性(P＜0.05)。结论:成功制备出符合新型根管封闭剂要求的PHMG根管封闭剂;PHMG浓度在0.8%~1.4%之间的根管封闭剂性能最佳。     

Long root of deciduous anterior teeth

A 24-year-old female Japanese patient presented with remarkably long roots of retained deciduous anterior teeth and permanent anterior teeth in the upper and lower jaw. Four lower anterior teeth were extracted for esthetic reasons. The patient had no apparent clinical syndrome related to the teeth or jaw, nor did there appear to be a family history of this condition. The extracted teeth and their lengths were as follows: the lower right deciduous lateral incisor was 25.55 mm long (root length, 18.95 mm); the lower left deciduous lateral incisor was 22.10 mm long (root length, 17.25 mm); the lower right deciduous canine was 27.95 mm long (root length, 20.60 mm); and the lower left deciduous canine was 23.90 mm long (root length, 17.65 mm).     

生物玻璃在龈下刮治和根面平整中的疗效评价

目的:研究龈下刮治和根面平整后局部应用生物玻璃对牙周临床指标及患者敏感症状的影响。方法:共纳入慢性牙周炎患者60名,采用双盲设计,随机将患者分为粉膏组(生物玻璃粉剂与生物玻璃膏剂)、粉剂组(生物玻璃粉剂与安慰膏剂)、膏剂组(安慰粉剂与生物玻璃膏剂)和对照组(粉剂与膏剂均为安慰剂)。刮治后牙周袋内应用粉剂,6周内以膏剂刷牙。刮治后1、2、3周以及6周时,检测冷刺激敏感度;刮治后6周及3个月时,记录牙龈出血指数(bleeding index,BI)、探诊深度(probing depth,PD)和临床附着丧失(clinical attachment loss,CAL)。结果:生物玻璃粉剂与膏剂的应用对刮治后1、2、3周的牙本质敏感度均有明显的缓解作用。刮治后6周,对照组的牙本质敏感状况也基本消失,各组间差异不再有统计学意义;刮治后6周,应用生物玻璃粉剂或膏剂组的BI值均有明显降低;应用生物玻璃粉剂组在刮治后6周时的PD和CAL值均小于未应用组,且应用生物玻璃粉剂或膏剂对刮治后3个月的CAL水平均有一定改善作用。结论:牙周刮治后的牙本质敏感在6周内多可自行缓解,而生物玻璃粉剂和含有7%生物玻璃的膏剂均可有效降低敏感的发生率和敏感程度;生物玻璃同时还具有明显的抗炎作用,可有效降低BI,改善PD和CAL。     

A new method to test the fracture strength of endodontically-treated root dentin

ObjectiveTo develop a new method to test the fracture strength of endodontically-treated root dentin.MethodBovine tooth roots were transversely cut into 2-mm thick sections and the root canals were enlarged with a taper of 0.06. An outer layer of resin composite was bonded to each section to make the root canal-to-outer radius ratio smaller than 1/3. The resulting discs were treated with irrigants at the inner surface and then fractured by inserting through the center a steel rod of the same taper attached to a universal test system. Fracture strength was calculated by using Lame’s equations for thick-walled cylinders. Micro-indentation was performed to evaluate the depth of dentin affected by irrigation. Finite element analysis (FEA) was performed to verify the reasonableness of using resin composite to surround the dentin section as well as the analytical solution.ResultsThe fracture strength of endodontically-treated root dentin based on the analytical solution for a homogeneous section was 139.69 ± 32.59 MPa. However, FEA that took into account root canal softening caused by the irrigants showed that this was overestimated by about 33.5%. The corrected fracture strength of treated dentin was 114.58 ± 26.74 MPa. By incorporating the layer of affected dentin into the analytical solution, the difference in the fracture-causing stress between the analytical and numerical solutions dropped to around 9.5%.SignificanceA relatively simple but clinically relevant method has been developed for measuring the fracture strength of endodontically-treated root dentin. The method could be applied to root dentin that is treated by conventional canal opening and irrigation.