Mastication

咀嚼
  • 文章类型: Journal Article
    背景:颌骨肿瘤疾病需要有效的治疗,通常涉及下颌的连续性切除。通过微血管骨瓣重建,如旋髂深动脉皮瓣(DCIA),是标准的。计算机辅助规划(CAD)提高了使用患者特异性CT图像来创建三维(3D)模型的重建精度。有关CAD计划的DCIA襟翼精度的数据很少。此外,准确性数据应与植入物的精确定位数据相结合,以实现良好的牙科修复。这项研究的重点是CAD计划的DCIA皮瓣的准确性和正确定位以进行假肢康复。
    方法:对CAD计划的DCIA皮瓣重建的下颌骨切除术后患者进行评估。术后X线片衍生的3D模型与CAD截骨位置计划中的3D模型对齐,angle,和皮瓣体积比较。为了评估DCIA皮瓣对假牙修复的适用性,在支撑区创建了一架飞机,并在DCIA皮瓣的中部创建了一架飞机。旋转下颌以闭合嘴,并测量两个平面之间的距离。
    结果:20例患者(12例男性,包括8名女性)。平均缺陷尺寸为73.28±4.87mm;11L缺陷,9个LC缺陷。计划与实际DCIA移植体积差为3.814±3.856cm²(p=0.2223).背侧截骨术与计划角度的偏差明显大于腹侧(p=0.035)。腹侧截骨术计划的DCIA移植与实际的DCIA移植之间的线性差异为1.294±1.197mm,背侧为2.680±3.449mm(p=0.1078)。牙轴与DCIA移植中部之间的差异范围为0.2mm至14.8mm。第一前磨牙区域的平均横向差为2.695±3.667mm。
    结论:CAD计划的DCIA皮瓣是重建下颌骨的解决方案。CAD计划可实现精确的重建,从而实现牙科植入物的放置和牙科修复。
    BACKGROUND: Tumorous diseases of the jaw demand effective treatments, often involving continuity resection of the jaw. Reconstruction via microvascular bone flaps, like deep circumflex iliac artery flaps (DCIA), is standard. Computer aided planning (CAD) enhances accuracy in reconstruction using patient-specific CT images to create three-dimensional (3D) models. Data on the accuracy of CAD-planned DCIA flaps is scarce. Moreover, the data on accuracy should be combined with data on the exact positioning of the implants for well-fitting dental prosthetics. This study focuses on CAD-planned DCIA flaps accuracy and proper positioning for prosthetic rehabilitation.
    METHODS: Patients post-mandible resection with CAD-planned DCIA flap reconstruction were evaluated. Postoperative radiograph-derived 3D models were aligned with 3D models from the CAD plans for osteotomy position, angle, and flap volume comparison. To evaluate the DCIA flap\'s suitability for prosthetic dental rehabilitation, a plane was created in the support zone and crestal in the middle of the DCIA flap. The lower jaw was rotated to close the mouth and the distance between the two planes was measured.
    RESULTS: 20 patients (12 males, 8 females) were included. Mean defect size was 73.28 ± 4.87 mm; 11 L defects, 9 LC defects. Planned vs. actual DCIA transplant volume difference was 3.814 ± 3.856 cm³ (p = 0.2223). The deviation from the planned angle was significantly larger at the dorsal osteotomy than at the ventral (p = 0.035). Linear differences between the planned DCIA transplant and the actual DCIA transplant were 1.294 ± 1.197 mm for the ventral osteotomy and 2.680 ± 3.449 mm for the dorsal (p = 0.1078). The difference between the dental axis and the middle of the DCIA transplant ranged from 0.2 mm to 14.8 mm. The mean lateral difference was 2.695 ± 3.667 mm in the region of the first premolar.
    CONCLUSIONS: The CAD-planned DCIA flap is a solution for reconstructing the mandible. CAD planning results in an accurate reconstruction enabling dental implant placement and dental prosthetics.
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  • 文章类型: Journal Article
    一些与年龄相关的口腔健康问题与神经退行性疾病相关,如阿尔茨海默病(AD)。然而,健康衰老中的口运动功能障碍与病理性衰老中的不同尚不清楚。部分原因是对健康衰老中的皮质和生物力学(“神经机械”)控制的变化知之甚少。为此,我们调查了年轻和老年恒河猴(Macacamulatta)的自然摄食行为,以了解与年龄相关的舌头和下颌运动学差异。我们使用高分辨率双平面视频放射摄影和X线运动形态重建(XROMM)在3D中跟踪舌头和颌骨的运动。与年轻受试者相比,年龄较大的受试者在咀嚼过程中舌头运动的刻板印象减少,舌头运动相对于下颌运动的滞后更大。总的来说,我们的发现揭示了舌头和下颌运动学的年龄相关变化,这可能表明舌-颌协调受损。我们的研究结果对于发现用于AD早期诊断的潜在神经机械生物标志物具有重要意义。
    Several age-related oral health problems have been associated with neurodegenerative diseases such as Alzheimer\'s Disease (AD), yet how oromotor dysfunction in healthy aging differ from those found in pathological aging is still unknown. This is partly because changes in the cortical and biomechanical (\"neuromechanical\") control of oromotor behavior in healthy aging are poorly understood. To this end, we investigated the natural feeding behavior of young and aged rhesus macaques (Macaca mulatta) to understand the age-related differences in tongue and jaw kinematics. We tracked tongue and jaw movements in 3D using high-resolution biplanar videoradiography and X-ray Reconstruction of Moving Morphology (XROMM). Older subjects exhibited a reduced stereotypy in tongue movements during chews and a greater lag in tongue movements relative to jaw movements compared to younger subjects. Overall, our findings reveal age-related changes in tongue and jaw kinematics, which may indicate impaired tongue-jaw coordination. Our results have important implications for the discovery of potential neuromechanical biomarkers for early diagnosis of AD.
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  • 文章类型: Journal Article
    背景:关于怀孕期间咀嚼khat对胎儿和妊娠的影响知之甚少。本研究的目的是确定怀孕期间咀嚼khat对埃塞俄比亚部分妊娠结局的影响,2022年:采用广义结构方程建模分析方法的队列研究。
    方法:在埃塞俄比亚东部的选定医院进行了一项基于机构的前瞻性队列研究。包括在满足资格标准的研究期间访问研究区域中的选定医院的孕妇,直到满足样本量(344)。本研究中研究的主要结局是早产和低出生体重。通过人体测量和临床测量收集数据,面试官进行问卷调查。进行生存分析和广义线性模型分析以估计粗略和调整后的相对风险和归因风险。使用数据科学统计软件(Stata)“GSEM”命令进行广义结构方程建模(GSEM)分析,以检查调解效果。
    结果:出现早产的风险明显高于阿拉伯茶咀嚼者[调整后相对危险度(aRR)=2.19;95CI1.21-3.96]。在调整妊娠高血压和剖宫产后的进一步分析中,怀孕期间咀嚼卡塔对早产的回归系数从路径n减小,β=0.37,p<0.001到路径n\',β=0.15,p<0.005。Khat咀嚼者发生低出生体重的风险明显更高(aRR=4.17;95CI2.11-8.25)。在调整妊娠高血压后的进一步分析中,剖宫产,早产和母体贫血,怀孕期间咀嚼卡塔对低出生体重的回归系数从路径q减小,β=0.4,p<0.001到路径q',β=0.2,p<0.001。
    结论:总体而言,目前的研究表明,咀嚼khat不仅是当前人口的担忧,也是影响未出生胎儿的一代的公共卫生问题。
    BACKGROUND: Little is known about the fetal and pregnancy effects of khat chewing during pregnancy. The aim of the current study was to determine the impact of chewing khat during pregnancy on selected pregnancy outcomes in Ethiopia, 2022: A Cohort Study with a Generalized Structural Equation Modeling Analysis Approach.
    METHODS: An institution-based prospective cohort study was employed in selected hospitals in eastern Ethiopia. Pregnant women who visited the selected hospitals in the study area during the study period that fulfilled the eligibility criteria were included until a sample size (344) was fulfilled. The main outcomes studied in the present study were preterm birth and low birth weight. Data were collected through anthropometric and clinical measurements, and interviewers administered questionnaires. The survival analysis and generalized linear model analysis were performed to estimate the crude and adjusted relative risk and attributable risk. The Generalized Structural Equation Modeling (GSEM) analysis was performed using the Statistical software for data science (Stata) \'GSEM\' command to examine the mediation effect.
    RESULTS: The risk of occurrence of preterm birth was significantly higher among khat chewers [adjusted relative risk (aRR) = 2.19; 95%CI 1.21-3.96]. In further analysis after adjusting for gestational hypertension and cesarean delivery, the regression coefficient of khat chewing during pregnancy on preterm birth has been decreased in size from path n, β = 0.37, p<0.001 to path n\', β = 0.15, p<0.005. The risk of occurrence of low birth weight among khat chewers was significantly higher (aRR = 4.17; 95%CI 2.11-8.25). In further analysis after adjusting for gestational hypertension, cesarean delivery, preterm birth and maternal anemia, the regression coefficient of khat chewing during pregnancy on low birth weight has been decreased in size from path q, β = 0.4, p<0.001 to path q\', β = 0.2, p<0.001.
    CONCLUSIONS: Overall, the present study revealed that khat chewing is not only a worry of the current population but also a public health concern of the generation affecting unborn fetuses.
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  • 文章类型: Journal Article
    背景:老化对组织适应性和数字闭塞器保留的影响仍在研究中。
    方法:扫描上颌Armany(I类)环氧树脂参考模型,以制造由铣削的Co-Cr框架和3D打印灯泡制成的数字闭塞器。使用Geomagic软件制作扫描参考和数字闭塞器的彩色图,以评估使用ROBOTA咀嚼模拟器在37,500、75,000和150,000个循环循环加载之前和之后的拟合精度,以模拟临床3-,6个月和12个月的咀嚼情况。使用重复的360、720和1440循环进行模拟闭塞器的放置和移除的插入-移除条件,并在重复的循环之前和之后评估保留。收集数据,使用社会科学统计软件包(IBMSPSSStatistics26)进行表格和统计分析。使用学生t检验和多变量ANOVA检验来检测显著性。P值<0.05被认为是显著差异。
    结果:对于保留测试:基线和3、6和12个月之间存在显著差异。对于组织表面适应性测试:在施加负荷之前和之后,在所有测量区域存在显著差异(P值<0.05)。
    结论:数字设计和制造的闭塞器是高度保持性的,并且在制造时具有出色的组织表面适应性,施加负荷后;导致保留减少和缺乏组织适应。临床意义:本手稿的目的是数字闭塞器可以成功使用,但缺点是松开保留和适应之后。所以,临床试验应该调查这些缺点的临床接受程度。
    BACKGROUND: Effect of aging on tissue adaptability and retention of digital obturator is still under investigation.
    METHODS: A maxillary Armany (class I) epoxy reference model was scanned to fabricate digital obturator fabricated from milled Co-Cr framework and 3D printed bulb. A color map of the scanned reference and digital obturator was made using Geomagic software to evaluate the accuracy of fit before and after cyclic loading using ROBOTA chewing simulator at 37,500, 75,000 and 150,000 cycles to simulate clinically 3-, 6- and 12-months chewing condition. Insertion-removal condition simulating the placement and removal of the obturator was done using repeated 360, 720 and 1440 cycles and retention was evaluated before and after the repeated cycles. Data were collected, tabulated and statistically analyzed using Statistical Package for Social Sciences (IBM SPSS Statistics 26). Student t-test and multi variable ANOVA test were used to detect significance. P-value < 0.05 was considered significant difference.
    RESULTS: For retention test: There was a significant difference between baseline and 3, 6 and12 months. For the tissue surface adaptation test: There was significant difference at all measured areas (P-value < 0.05) before and after application of load.
    CONCLUSIONS: digitally designed and fabricated obturator was highly retentive and has excellent tissue surface adaptation upon fabrication, After application of load; reduction of retention and lack of tissue adaptation were resulted. THE CLINICAL IMPLICATION: of this manuscript is that digital obturator can be used successfully with the shortcomings of loosening retention and adaptation afterwhile. So, clinical trials should investigate the clinical acceptance of these shortcomings.
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  • 文章类型: Journal Article
    背景:槟榔咀嚼,在东南亚和南亚普遍存在,涉及到槟榔叶等成分,槟榔,熟石灰,有时烟草。这项研究旨在评估槟榔的颊粘膜变化,开发一种评估暴露的临床工具,并研究其在预测发育不良方面的可用性。
    方法:在获得伦理批准和知情同意后,患者从政府医学院门诊部招募,Omandurar,政府地产,印度。计算的目标样本大小为200。数据包括槟榔咀嚼的历史,口腔细胞学获得的颊粘膜细胞,以及病理学家评估的载玻片发育不良的严重程度。我们利用主成分分析(PCA)和验证性因子分析(CFA)来验证反映核形态参数(NMP)的新结果变量。基于槟榔暴露和添加剂,开发了槟榔年的乘法回归模型。使用Spearman相关性和Kruskal-Wallis检验来检查槟榔年与发育不良之间的关联。
    结果:不同咀嚼组的NMPs存在显著差异。我们推导了槟榔年的乘法回归模型。在对数变换方法中,槟榔年=0.05×槟榔暴露×0.09×消石灰用量×0.11×烟草用量。在原始变量方法中,槟榔年=5.05×槟榔暴露量^0.00048×熟石灰用量^0.18133×烟草用量^1.47513。Spearman相关性和Kruskal-Wallis检验证实与发育不良有关。
    结论:槟榔年是评估终生槟榔暴露的开创性工具,类似于打包吸烟年。它可以帮助风险分层,有针对性的干预措施和制定公共卫生政策。尽管有局限性,槟榔年有望彻底改变口腔健康风险评估,未来的研究可以在全球范围内扩展其范围,考虑到不同的槟榔成分。
    BACKGROUND: Betel quid chewing, prevalent in Southeast Asia and South Asia, involves components such as betel leaf, areca nut, slaked lime, and sometimes tobacco. This study aims to assess buccal mucosa changes in betel quid chewers, develop a clinical tool for assessing exposure, and investigate its usability in predicting dysplasia.
    METHODS: After obtaining ethical approval and informed consent, patients were recruited from the Out-Patient Department of Government Medical College, Omandurar, Government Estate, India. A target sample size of 200 was calculated. The data included the history of betel quid chewing, buccal mucosa cells obtained by oral cytology, and the severity of dysplasia of the slides assessed by pathologists. We utilized principal component analysis (PCA) and confirmatory factor analysis (CFA) to validate a new outcome variable reflecting nuclear morphometric parameters (NMPs). Multiplicative regression models were developed for betel years based on betel exposure and additives. Spearman correlation and Kruskal-Wallis test was used to check the association between betel years and dysplasia.
    RESULTS: Significant differences in NMPs were observed among different betel chewing groups. We derived multiplicative regression models for betel years. In the logarithmic transformation approach, betel year = 0.05×betel-exposure×0.09×slaked-lime use×0.11×tobacco-use. In the original variable approach, betel year = 5.05×betel-exposure^0.00048×slaked-lime-use^0.18133×tobacco-use^1.47513. Spearman correlation and Kruskal-Wallis tests confirmed associations with dysplasia.
    CONCLUSIONS: Betel year is a pioneering tool for assessing lifetime betel quid exposure, similar to pack years for smoking. It could aid in risk stratification, targeted interventions and shaping public health policies. Despite limitations, betel year holds promise for revolutionizing oral health risk assessment, and future research can expand its scope globally, considering diverse betel quid compositions.
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  • 文章类型: Journal Article
    带和环空间保持器用于保持早期丢失的落叶磨牙的缺失空间。当第二个落叶磨牙过早丢失时,当第一恒磨牙是基牙时,在不同发育程度上的应力可能会有所不同。空间维护器的设计和使用也可能导致回路的损坏。本文的目的是使用有限元方法研究在有或没有咬合接触的情况下,第一恒磨牙和环上的应力,以四个不同发育程度的第一恒磨牙作为基牙。我们旨在指导空间维持器的临床设计和使用。
    我们开发了下颌第一恒磨牙和带环空间保持器的有限元模型,模拟牙槽骨,牙周膜(PDL),牙釉质和牙本质.四个发育阶段为1/2(I),2/3(II),3/4(III)和全面发展(IV)。AnsysWorkbench用于分析牙根发育和环与对颌之间的咬合接触对基牙和环的影响。基牙以70N的力垂直和倾斜地静态加载。环以14N的力垂直静态加载。计算了所有结构上的应力和环的位移趋势。
    搪瓷上的应力,牙本质,PDL和牙槽骨相似,浓度一致。但是如果有咬合接触,环在与前牙接触的近中间边缘产生最大位移。当环与相对的咬合牙咬合接触时,垂直荷载作用下空间保持者等效应力峰值为:Ⅰ组>Ⅳ组>Ⅲ组>Ⅱ组,最大主应力峰值变化为:Ⅰ组>Ⅲ组>Ⅱ组>Ⅳ组。斜荷载下回路等效应力峰值的变化为:Ⅰ组>Ⅲ组>Ⅳ组>Ⅱ组,最大主应力峰值变化为:III组>I组>II组>IV组。当环不与相对的咬合牙咬合接触时,垂直荷载作用下空间保持者等效应力峰值为:IV组>I组>II组>III组,最大主应力峰值变化为:IV组>I组>II组>III组。斜荷载作用下空间保持器等效应力峰值的变化为:Ⅰ组>Ⅳ组>Ⅱ组>Ⅲ组,最大主应力峰值变化为:Ⅰ组>Ⅳ组>Ⅱ组>Ⅲ组。
    我们的结果表明,只要有可能,建议选择根部发育接近完整的牙齿作为空间保持者的基牙。带和环空间保持器的设计和使用应避免咬合与咬合牙齿接触,以防止环变形。
    UNASSIGNED: The band and loop space maintainer is used to maintain the missing space of deciduous molars which are lost early. When the second deciduous molar is lost prematurely, the stress on the first permanent molar during different degrees of development may vary when it is the abutment. The design and use of the space maintainer may also lead to damage of the loop. The purpose of this article is to use the finite element method to study the stress on the first permanent molar and the loop with or without occlusal contact, with the first permanent molar of four different degrees of development serving as the abutment. We aimed to guide the clinical design and use of the space maintainer.
    UNASSIGNED: We developed finite element models of the mandibular first permanent molar and the band and loop space maintainer, and simulated alveolar bone, periodontal ligament (PDL), enamel and dentin. The four developmental stages were 1/2 (I), 2/3 (II), 3/4 (III) and full development (IV). Ansys Workbench was used to analyze the effects of root development and occlusal contact between the loop and the opposite jaw on abutment teeth and the loop. Abutment teeth were statically loaded vertically and obliquely with a force of 70 N. The loop was statically loaded vertically with a force of 14 N. The stress on all structures and the displacement trends of the loop were calculated.
    UNASSIGNED: The stress on enamel, dentin, PDL and alveolar bone were similar, and the concentration was consistent. But if there was occlusal contact, the loop produced maximum displacement at the near middle edge of contact with the anterior teeth. When the loop was in occlusal contact with the opposing occlusal tooth, the peak value of the equivalent stress on the space maintainer under vertical load was: group I > group IV > group III > group II, and the maximum principal stress peak change was: group I > group III > group II > group IV. The change of the equivalent stress peak value of the loop under oblique load was: group I > group III > group IV > group II, and the maximum principal stress peak change was: group III > group I > group II > group IV. When the loop was not in occlusal contact with the opposing occlusal tooth, the peak value of the equivalent stress on the space maintainer under vertical load was: group IV > group I > group II > group III, and the maximum principal stress peak change was: group IV > group I > group II > group III. The change of the equivalent stress peak value of the space maintainer under oblique load was: group I > group IV > group II > group III, and the maximum principal stress peak change was: group I > group IV > group II > group III.
    UNASSIGNED: Our results suggested that whenever possible, choosing the teeth with nearly complete root development as the abutment of the space maintainer is advisable. The design and use of the band and loop space maintainer should avoid occlusal contact with the occlusal teeth to prevent deformation of the loop.
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  • 文章类型: Journal Article
    积极的管理做法,以减少或促进特定的植被,被称为植被处理,是环境管理的一个常见部分,它们用于各种目的,包括减轻野火风险,入侵物种管理,和生态恢复。在过去的几十年中,特别是在美国西部,用于减轻野火的植被处理急剧增加。虽然植被处理很常见,有关时间的数据,location,所进行的治疗类型通常仅由进行工作的组织维持,阻碍管理者和研究人员了解整个景观中植被处理的分布和时机的能力。该数据集是植被处理的空间参考记录的集合,例如机械变薄,规定燃烧,以及在新墨西哥州进行的除草剂应用,美国和科罗拉多州的邻近部分,俄克拉荷马州,和德克萨斯州。空间数据是通过向相关机构的区域或州办事处提出的请求收集的(例如,土地管理局,美国森林服务局,新墨西哥州林业局)。通过在新墨西哥州五个随机选择的重点流域进行更密集的数据收集来评估这种数据收集方法的准确性。在这些流域中,联系了较大机构的当地办事处,以及任何较小的团体(例如,水土保持区,市政当局,和环境非营利组织),并亲自访问以收集有关植被处理的任何信息。整个数据集包括跨越一个世纪的治疗记录,包括由十几个不同组织进行的990万英亩治疗记录。在我们调查的五个重点分水岭中,数据库中的处理土地面积比更密集的访谈方法少7.4%。这个关于植被处理的空间广泛的数据集将有助于研究人员量化或建模植被管理对火灾风险和行为的影响。此外,这些数据将对研究分布的生态学家有用,运动,以及各种植物和动物物种的栖息地协会。最后,这些数据将有助于景观保护和管理的研究。
    Active management practices to reduce or promote particular vegetation, known as vegetation treatments, are a common part of environmental management and they are conducted for a variety of purposes including wildfire risk mitigation, invasive species management, and ecological restoration. Vegetation treatment for wildfire mitigation in particular have increased dramatically in the Western United States in the past several decades. While vegetation treatments are common, data regarding the timing, location, and type of treatments conducted are often only maintained by the organization that conducted the work, hampering the ability of managers and researchers to understand the distribution and timing of vegetation treatments across a landscape. This dataset is a collection of spatially referenced records of vegetation treatments such as mechanical thinning, prescribed burning, and herbicide applications that were conducted in the state of New Mexico, USA and adjacent parts of Colorado, Oklahoma, and Texas. Spatial data were collected through requests to the regional or state offices for the relevant agencies (e.g., The Bureau of Land Management, the U.S. Forest Service, New Mexico State Forestry Division). The accuracy of this data collection approach was assessed by conducting more intensive data collection in five randomly selected focal watersheds across New Mexico. In these watersheds local offices of the larger agencies were contacted, as well as any smaller groups (e.g., soil and water conservation districts, municipalities, and environmental non-profits), and in person visits were made to gather any information on vegetation treatments possible. The overall dataset includes records of treatments spanning a century and includes records of 9.9 million acres of treatments conducted by more than a dozen different organizations. In the five focal watershed that we surveyed the database contained 7.4 % fewer acres of treated land than the more intensive interview approach. This spatially extensive dataset on vegetation treatments will be useful for researchers quantifying or modelling the effect of vegetation management on fire risk and behaviour. Additionally, this data will be useful to ecologists studying the distribution, movement, and habitat associations of a variety of plant an animal species. Finally, this data will be useful for research on landscape conservation and management.
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  • 文章类型: Journal Article
    再吸收牙槽脊,特别是在下颚,有一个小的义齿支撑区,这可能会导致咀嚼负荷的应力分布超过压力-疼痛阈值(PPT),并引起粘膜疼痛或潜在地加重脊吸收。因此,在双边平衡(BBO)中选择理想的咬合方案,语言化(LO),单平面(MO)对于这样的条件变得至关重要。实验是使用有限元方法对下颌中再吸收的牙槽脊进行建模的,上面放置了三个假牙,根据BBO的齿排列,每个都有不同的加载点,LO,和MO。轴向载荷为100N,BBO和LO的最终斜载分别为119N和106N,分别。冯·米塞斯对BBO的强调,LO,在九个义齿支撑区域观察到MO,结果表明,对于BBO,轴向载荷不会产生超过PPT值(0.64925MPa)的应力,LO,和MO在区域H上的最高值,0.43229MPa,0.39715MPa,和0.31576兆帕,分别。然而,倾斜载荷方向表明BBO的面积(面积E0.80778MPa和面积H0.76256MPa)超过PPT的面积比LO(面积E0.64394MPa)多。语言咬合方案是理想的患者再吸收牙槽的条件,特别是当义齿在保持舒适性的同时仍提供良好的咀嚼性能和令人满意的美学效果时限制干扰。
    Resorbed alveolar ridges, particularly in the lower jaw, have a small denture supporting area, which may cause the stress distribution of mastication load to exceed the pressure-pain threshold (PPT) and induce pain in the mucosa or potentially worsen the ridge resorption. Thus, choosing the ideal occlusal scheme among bilateral balanced (BBO), lingualized (LO), and monoplane (MO) for such conditions becomes crucial. The experiment was conducted using the finite element method on a modeling of a resorbed alveolar ridge in the lower jaw with three dentures placed on top, each of which was given different loading points according to the tooth arrangement of BBO, LO, and MO. The axial load was 100 N, and the resultant oblique loads on BBO and LO were 119 N and 106 N, respectively. The von Mises stresses for BBO, LO, and MO were observed in nine denture-supporting areas, and the results showed that the axial load did not produce stresses that exceeded the PPT value (0.64925 MPa) for BBO, LO, and MO with the highest value on area H, 0.43229 MPa, 0.39715 MPa, and 0.31576 MPa, respectively. However, the oblique load direction showed that the BBO had more areas (area E 0.80778 MPa and area H 0.76256 MPa) that exceeded the PPT than LO (area E 0.64394 MPa). The lingualized occlusal scheme is ideal for patients with resorbed alveolar ridge conditions, especially in terms of limiting interferences when the denture is functioning while maintaining comfort but still providing good masticatory performance and satisfactory esthetics.
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  • 文章类型: Journal Article
    颅骨成形术(CP)用于修复去骨瓣减压术后的颅骨缺损。在此过程中,颞部肌肉可以朝向基部收缩或缩回并且粘附到硬脑膜上方和/或下方的头皮皮瓣。CP后可能会出现一些并发症,包括功能和美容问题。本研究介绍了CP的技术注释和结果。
    这项回顾性观察性研究收集了2019-2022年在我们医院使用未分离的肌肉硬膜技术进行的CP程序的数据。提出了有关颞肌与硬脑膜缺乏分离的技术说明。将骨瓣或钛网放置在颞肌层上方,它仍然附着在硬脑膜上。使用OHIP-14问卷评估咀嚼质量的功能结果。
    23例患者纳入本研究。初次手术主要由创伤引起(65.2%)。大多数患者接受自体骨瓣CP(52.2%),在此期间,骨瓣被储存在腹部皮下袋或冷沉淀。只有一名患者在CP后出现咀嚼问题(p<0.001)。时间空洞化仍然是该技术中的一个问题。然而,解剖颞肌以减少颞部空洞化会导致面神经损伤和咀嚼问题。由于缺乏颞部肌肉操纵,我们的病人有轻微的咀嚼问题.
    应该进行CP以改善功能和美学结果。可以选择颞部肌肉不与硬脑膜分离的CP技术,以避免手术后对肌肉的损伤和咀嚼问题。
    UNASSIGNED: Cranioplasty (CP) is used to repair cranial defects after decompressive craniectomy. During this procedure, the temporal muscle can contract or retract toward the base and adhere to the scalp flaps above and/or below the dura. Several complications including functional and cosmetic problems can occur following CP. This study presents the technical notes and outcomes of CP.
    UNASSIGNED: This retrospective observational study collect data of CP-procedures using unseparated muscle-dura technique performed at our hospital in 2019-2022. Technical note is presented regarding the lack of separation of the temporal muscles from the dura mater. A bone flap or titanium mesh was placed above the temporal muscle layer, which was still attached to the dura mater. Functional outcomes were evaluated using OHIP-14 Questionnaire to assess mastication quality.
    UNASSIGNED: Twenty-three patients were included in this study. Initial surgeries were mostly caused by trauma (65.2%). Most patients underwent autologous bone flap CP (52.2%), during which the bone flap was stored in either the abdominal subcutaneous pocket or cryoprecipitated. Only one patient experienced mastication problems after CP (p<0.001). Temporal hollowing remained a problem in this technique. However, dissection of the temporalis muscle to reduce temporal hollowing can cause facial nerve injuries and masticatory problems. Due to the lack of temporal muscle manipulation, our patients had minimal mastication problems.
    UNASSIGNED: CP should be performed to improve functional and aesthetic outcomes. A CP technique with the temporal muscle unseparated from the dura mater can be selected to avoid damage to the muscle and mastication problems after surgery.
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  • 文章类型: Journal Article
    这项研究旨在通过检查临床病史来预测牙科高速公路空间,习惯,咬合参数,下颌硬组织运动,软组织运动,肌肉活动,66名参与者的颞下颌关节功能。数据收集涉及基于视频的面部标志跟踪,下颌电声描记术,下颌运动范围的表面肌电图,高速公路空间,咀嚼任务,语音表达,关节振动分析,和咬合的3D颌骨扫描。这导致了121个预测特征的数据集,以高速公路空间为目标变量。六个模型在500到25,000个观测值的合成数据上进行了训练,保留65个原始观察值用于测试:线性回归,随机森林,CatBoostRegressor,XGBoostRegressor,多层感知器神经网络(MPNN),TabNet可解释的人工智能表明,高速公路空间的关键预测因素包括语音学,静息颞肌活动,咬紧时下颌肌肉活动,体重,下颌硬组织侧向位移,和牙弓参数。CatBoost使用5000个合成数据点,测试误差为0.65mm,完善的MPNN通过25,000个合成数据点和121个独特的预测因子实现了最佳性能,在65个原始观测值上产生0.43毫米的绝对误差。
    This study aimed to predict dental freeway space by examining the clinical history, habits, occlusal parameters, mandibular hard tissue movement, soft tissue motion, muscle activity, and temporomandibular joint function of 66 participants. Data collection involved video-based facial landmark tracking, mandibular electrognathography, surface electromyography of mandibular range of motion, freeway space, chewing tasks, phonetic expressions, joint vibration analysis, and 3D jaw scans of occlusion. This resulted in a dataset of 121 predictor features, with freeway space as the target variable. Six models were trained on synthetic data ranging from 500 to 25,000 observations, with 65 original observations reserved for testing: Linear Regression, Random Forest, CatBoost Regressor, XGBoost Regressor, Multilayer Perceptron Neural Network (MPNN), and TabNet. Explainable AI indicated that key predictors of freeway space included phonetics, resting temporalis muscle activity, mandibular muscle activity during clenching, body weight, mandibular hard tissue lateral displacements, and dental arch parameters. CatBoost excelled with a test error of 0.65 mm using 5000 synthetic data points, while a refined MPNN achieved the best performance with 25,000 synthetic data points and 121 unique predictors, yielding an absolute error of 0.43 mm on the 65 original observations.
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