The association between the disruption of motor imagery and the number of depressive episodes of major depression

Background

Mental rotation performance may be used as an index of mental slowing or bradyphrenia, and may reflect, in particular, speed of motor preparation. Previous studies suggest depressive patients present the correlates of impaired behavioural performance for mental rotation and psychomotor disturbance. The aim of this study is to compare the mental rotation abilities of patients with a first episode of depression, recurrent depression and healthy control subjects with regard to hand tasks.

Methods

We tested 32 first episode of depression, 38 recurrent depression and 36 healthy control subjects by evaluating the performance of depressed patients with regard to the hand mental rotation tasks.

Results

First, the first episode and recurrent depression subjects were significantly slower and made more errors than controls in mentally rotating hands. Second, the first depressive episode but not the recurrent depression displayed the same pattern of response times to stimuli at various orientations relative to control subjects in the hand task. Third, in particular, recurrent depression subjects were significantly slower and made more errors during the mental transformation of hands than first depressive episode relative to control subjects and the differences were significantly larger in female than male subjects in the mental rotation hand task.

Limitations

Patients were on antidepressant medication.

Conclusions

These results suggest that the impaired behavioural performance for mental representation processing are related to the number of previous episodes. Moreover, the recurrent major depressive episodes may contribute to the reinforcement of cognitive impairments and further the development or maintenance of mental representation dysfunctions, especially in female patients. A deficit on mental rotation in the depressive patients may be potential biomarkers for recurrence chronically.     

儿童口腔门诊全身麻醉操作指南

近年来,在全身麻醉状态下完成门诊儿童口腔诊疗,已逐渐发展成为一种较成熟的行为管理模式。由于门诊儿童口腔诊治时间短、流动性大、周转快,对麻醉及诊疗期的管理提出更高要求。中华口腔医学会镇静镇痛专业委员会组织专家,制定儿童口腔门诊全身麻醉操作指南,从口腔门诊实施全身麻醉的范围、临床基本条件、口腔诊疗种类、诊治前评估与准备、麻醉实施与监测、恢复和苏醒期管理、常见并发症及处理要点等方面给出具有可操作性的实施规范,对促进我国儿童门诊全身麻醉下口腔诊疗安全性和舒适化的快速发展具有重要意义。     

Microarchitecture of medication-related osteonecrosis of the jaw (MRONJ); a retrospective micro-CT and morphometric analysis

Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (AR) drugs such as bisphosphonates (BP) and denosumab (Dmab). Although several risk factors are described, the etiology of MRONJ is still not fully elucidated. Bone-strengthening is the primary aim of antiresorptive therapy; however, overly increased bone mass and microcrack accumulation are also discussed in MRONJ etiologies. The aim of this study is to evaluate the microarchitecture of jaw bones with micro?computed tomography (micro-CT) in AR-treated patients with or without MRONJ.Human jaw bone samples of AR-treated patients were separated into 11 groups by AR treatment bisphosphonate (BP), denosumab (Dmab), both (M) and control groups. Subgroups were divided according to the clinical localization as AR-exposed vital jaw bone (BP_exp, Dmab_exp, M_exp), osteonecrosis–margin of a sequestrum (BPO_mar, DmabO_mar, MO_mar) and osteonecrosis–sequestrum (BPO_seq, DmabO_seq, MO_seq). Healthy jaw bone (C_HB) and osteoporotic jaw bone (C_OP) represent control groups. Samples underwent retrospective micro-CT and morphometric analysis in representative units by bone volume fraction (BV/TV), bone surface density (BS/BV), trabecular thickness (Tr.Th.), trabecular number (Tr.N.), trabecular space (Tr.Sp.), Euler characteristic for bone connectivity, bone mineral density (BMD) and tissue mineral density (TMD).A total of 141 samples from 78 patients were analyzed. BV/TV of M_exp group (mean: 0.46 ± 0.27) was significantly higher than in the C_OP group (mean: 0.14 ± 0.05; p = 0.0053). Tr.Th. differed significantly between the BP_exp group (mean: 0.32 ± 0.15) and the M_exp group (mean: 0.57 ± 0.20; p = 0.0452) as well as between the BPO_seq group (mean: 0.25 ± 0.10) and the MO_seq group (mean: 0.39 ± 0.18; p = 0.0417). Signs of trabecular thickening and unorganized trabecular microarchitecture from AR-exposed- to sequestrum groups, were analyzed in 3D reconstructions. However, BS/BV, Tr.N., and Tr.Sp. showed no significant differences. Euler characteristic of the BPO_seq group (median: 7.46) doubled compared to that of the BP_exp group (median: 14.97; p = 0.0064). Mineralization parameters BMD and TMD were similar in all groups.Findings show evidence of enhanced bone mass and suspect microarchitecture in some AR-treated jaw bone compared to osteoporotic jaw bone. Despite increased bone mass, some MRONJ samples showed decreased trabecular connectivity by Euler characteristic compared to AR-treated jaw bone. These samples may indicate extensive ossification and ineffective bone mass with superficially higher bone mass without existing or even reduced mechanical stability, indicated by connectivity loss. This result might also suggest a high risk to microcrack accumulation. At some point, possibly some kind of over-ossification could lead to under-nourishment and microarchitectural weakness, creating instability, subsequently increasing vulnerability to MRONJ.     

Association between shape of the mandibular condylar head and the occurrence of unilateral condylar fracture – A retrospective computed tomographic study

This retrospective study aims to evaluate the correlation between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture using computed tomography.Medical records of patients diagnosed with unilateral condylar fractures from the year 2012–2019 were reviewed. The shape of the condylar head on the non - fractured side was analysed using a Radiant Dicom Viewer. The analysis was done using both visual and analytical methods. In the analytical method, a horizontal line was drawn at the base of the curvature of the condylar head. The highest peak point of the head was marked, and a perpendicular line was drawn connecting the highest point to the horizontal line. The shape was categorized into four types as convex, flat, angled, and round based on these lines.201 CT scans were examined, of which 69 were excluded as they did not meet the inclusion criteria. The remaining 132 were included in our study. On examining the shape, flat-shaped condyle was seen in 57 scans (43.2%), followed by convex in 31 scans (23.4%), angled in 30 (22.7%) and round in 14 scans (10.6%). The relationship between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture was analysed using a chi-square test, which showed high statistical significance (p value 0.0001). The flat-shaped condylar head was more prone to fracture, and the round-shaped condylar head was least prone to fracture.In conclusion, the shape of the mandibular condylar head had a statistically significant association with the incidence of unilateral condylar fracture. The assessment of the shape of the condylar head can be taken as a guide to suspect condylar fractures and other associated mandibular fractures.     

Clinical characteristics and risk factors of major oral ulcers in the mandibular retromolar region in children

Clinical Oral Investigations - To describe the characteristics of major aphthous ulcers (MjOU) in children and analyze its potential risk factors. Data were collected from the National Clinical...     

中华口腔医学杂志2019口腔种植学术研讨会——并发症及风险防控会议纪要

由《中华口腔医学杂志》编委会和中华口腔医学会共同主办的"中华口腔医学杂志2019口腔种植学术研讨会——并发症及风险防控"于2019年11月23至24日在广东省珠海市粤海酒店召开。本次研讨会分为牙周与种植并发症、修复设计与机械并发症、无牙颌的种植并发症以及上颌窦与骨增量并发症共4个版块,每个版块由专家主题演讲和专题讨论相结合,对各种种植并发症和风险问题进行集中研讨和辩论,对一些种植并发症及风险问题形成初步共识,以指导临床工作。     

颞下颌关节软骨对咬合力刺激响应特征的动物实验启示

关节软骨主要的功能之一是承受一定的运动负荷,颞下颌关节髁突软骨所承受的功能负荷与咬合密切相关,因而颞下颌关节髁突软骨可以随咬合的变化而进行相应的改建。我们利用大鼠、小鼠进行的实验研究显示,用佩戴金属冠的方法加高小鼠双侧前牙咬合(bilateral anterior elevation,BAE),可导致小鼠髁突软骨明显增厚;而用金属冠制作单侧前牙反[牙合](unilateral anterior crossbite,UAC)不良修复体,则可导致髁突软骨出现明显的退行性变,直至髁突变形。我们利用这些可导致髁突软骨出现增殖性或退行性改建的动物模型进行在体基因修饰实验,探索髁突软骨改建过程中与细胞自噬、凋亡、终末分化等活动密切相关的信号通路,例如哺乳动物雷帕霉素靶蛋白(mammalian target of rapmycin,mTOR)信号,印第安刺猬信号(India hedgehog,Ihh),以及甲状旁腺素及其相关蛋白受体信号等,其结论有望指导临床工作中在纠正异常咬合基础上,从细胞和分子水平干预软骨细胞功能,预防和治疗颞下颌关节软骨退变。     

乘风而上 迎难前行

随着《中华口腔医学杂志》第12期发稿单的签署,2019年即将成为过去,《中华口腔医学杂志》生命的年轮中又将增加1年的积累、1年的成长。崭新的2020年,正伴着春天的脚步向我们走来。辞旧迎新之际,我谨代表《中华口腔医学杂志》编辑部向辛勤工作在口腔医学医疗、教学、科研、预防及管理第一线的读者、作者、编者朋友们,向一年来为杂志积极投稿、奉献学术成果的作者朋友们,向为杂志荐稿、组稿、审稿的杂志编委朋友们,表示最真诚的新年祝福和最衷心的感谢。     

自体牙移植术前难度预判因素的筛选及分析

目的:设计自体牙移植术前难度预判量表,并进行统计学验证。方法:基于文献支持和临床经验总结,对自体牙移植术前难度预判的可能因素进行统计学分析,筛选出相关性较高的11条因素并编制量表,通过96病例进行实际难度判定。采用SPSS 23.0软件包对量表进行信度和效度检验。结果:对96例病例进行难度预判的结果进行统计学分析,量表检测的克隆巴赫系数（信度值）为0.853,皮尔逊相关系数（内容效度值）为0.745,KMO值（结构效度值）为0.704,以上检验均有统计学意义。结论:所设计自体牙移植术前难度预判量表合理可行,适用于初学者进行术前难度预判分析。