Development of a Device for Removing a Partial Denture in a Patient with Scleroderma

Scleroderma is a chronic disease that has been associated with immune dysfunction. One of the oral manifestations is microsomia, a result of collagen deposition in the perioral tissues. The complexity of treating these patients includes limited mouth opening ability, and difficulty inserting and removing dentures due to finger deformity. This article will describe an appliance specially designed especially for scleroderma patients, which facilitates treatment of the patient with removable partial dentures (RPD).     

Malodour in denture wearers: an ill-defined problem

Denture plaque has not been studied to the same extent as dental plaque, and although there are many similarities in microbial composition, there are some significant differences. Denture-induced stomatitis is associated with poor denture hygiene, a more acidogenic plaque and the presence of Candida albicans . Obligate Gram-negative anaerobic micro-organisms, although present in denture plaque, have rarely been specifically investigated. Opportunist pathogens including coliforms and staphylococci have been isolated from dentures. Teeth adjacent to partial dentures are more susceptible to caries and periodontal diseases, perhaps due to an increased plaque buildup at the prosthesis/tooth interface. Little work has been published on malodour associated with dentures. The inert material provides a substratum for the plaque biofilm, which encompasses a range of odour-producing species. The microbiology of the tongue in denture wearers has not been specifically studied. Thus the nature, origin and extent of malodour in denture wearers is ill-defined, but many species capable of producing malodorous compounds are present. The wide age and health range presented by denture wearers further confounds investigation. There is a need for further work in the area, both for cosmetic- and health-associated reasons in the increasing elderly population.     

Early Designs for the Occlusal Anatomy of Posterior Denture Teeth: Part III

Part III of this series of articles, like Part II, reviews the pioneering efforts in the 19th century to improve the quality of artificial teeth. The focus of this article, unlike that of Part II, is specifically modifications in the design of the occlusal anatomy of the 19th century denture teeth, along with the theories of mandibular movement that inspired those modifications. This article concludes the introductory phase of this project, which seeks to unravel the confusing history of the development of (posterior) denture teeth.     

种植义齿修复的医学伦理问题

种植义齿是一项新的修复缺失牙方法，本文从医学伦理学的角度出发，探究种植又齿修复过程中应遵循的医德原则，医师高度的责任心、精湛的医术和正确的口腔宣教是保证种植义齿修复成功的关键。     

弹性义齿修复的临床效果观察

目的：了解弹性义齿修复的临床效果，为临床应用提供参考。方法：152例门诊缺牙患者，制作弹性义齿修复体188件，上颌130件，下颌58件。Kennedy一类缺损修复6件，Kennedy二类缺损修复4件，Kennedy三类缺损修复102件，Kennedy四类缺损修复76件。通过1－4年的观察，从形态和功能、固定和稳定、颜色和美观以及对组织保健判断对义齿的满意程度，并进行临床效果评价。结果：79例95件弹性义齿具有良好的美观效果，颜色满意，感觉舒适，满意和较满意率达100％，Kennedy三、四类缺损修复率为94．74％。弹性义齿对Kennedy一类缺损修复的满意和比较满意率为66．67％；对Kennedy二类缺损修复的满意和比较满意率为50．00％；对Kennedy三类缺损修复的满意和比较满意率为96．15％；对Kennedy四类缺损修复的满意和比较满意率为84．21％。结论：(1)弹性义齿是一种美观、舒适、对基牙预备甚少的可摘局部义齿修复形式。（2）弹性义齿较适合咀嚼压力小而缺牙数目不多的前牙和前磨牙缺失的修复。     

Factors influencing survival of reconstructions. Consensus report of Working Group 2

Abstract: In order to evaluate the level of evidence of factors influencing the survival of reconstructions, systematic reviews of the relevant literature were prepared by a group of rapporteurs. The review papers were circulated to the members of the group before the conference and formed the basis for group and panel discussions. Subsequently, modifications were added to the review papers, and suggestions for consensus statements concerning the following topics were prepared and again critically reviewed in the group and in the plenum: Impact of (i) periodontal disease on the survival of tooth-supported reconstructions, (ii) post-surgical factors as supportive therapy on the survival of implant supported reconstructions, (iii) technical and/or biological complications on the survival of different types of reconstructions, (iiii) material choice for reconstructions on the survival of single crowns and fixed dental prostheses.     

义齿PMMA基托表面粗糙度影响的实验研究

目的：研究技工操作因素对义齿树脂基托表面粗糙度的影响。方法：在不同粉液比、充填时期、聚合温度、混合方式以及出盒温度成型的上颌半口义齿基托上选取1.5cm^2范围，按照统一的打磨顺序，由粗到细打磨抛光完成，浸入冷水中，7天后进行粗糙度测试，所得数据经t检验统计处理。结果：在单体含量降低组、丝状期充填组．热处理时直接放入70℃水中维持9h组与对照组相比，均存在显著差异（P〈0．05）。结论：影响PMMA树脂表面粗糙度的制作工艺因素有单体含量降低、丝状期充填和未经100℃高温热处理。     

Aspects of silicone rubber as an encapsulant for neurological prostheses

Silicone rubber is not, at first sight, a promising material with which to encapsulate a piece of implantable microelectronics expected to last ten or twenty years. It is well known to be very permeable to water. In fact, if correctly applied, it performs very well for ten years, possibly longer. The paper considers the part player by osmosis in achieving satisfactory performance combined with simple technology.     

带塑料插入件栓式附着体义齿修复后满意度的调查

目的 通过问卷调查表对患者戴用附着体义齿后的主观感受进行研究.方法 选择上下牙列缺损患者42例,共制作带塑料插入件栓式附着体义齿47例,于戴牙后1个月,患者基本适应戴用义齿,通过问卷调查,了解患者戴用义齿后的适应情况、对义齿的满意程度及咀嚼功能的变化等.结果 患者对带塑料插入件栓式附着体义齿和传统可摘局部义齿两种修复方式比较,在总的满意度、美观、舒适、咀嚼、语言、适应期、食物结构改变等方面,前者明显优于后者,差异有统计学意义.结论 带塑料插入件栓式附着体义齿在美观及功能上不仅能满足患者的要求,而且远优于传统可摘局部义齿.     

Contact finite element stress analysis of porous ingrowth acetabular cup implantation, ingrowth, and loosening

Two-dimensional linear and contact finite element analyses were conducted of total hip arthroplasty using metal-backed, porous ingrowth acetabular components. The stress transmission characteristics from the component to the surrounding bone were given special attention. Resultant loads of 20 and 40 degrees medial of vertical were studied, and the influence of adding a metal flange to the rim of the cup was evaluated. The results indicated that when a conventional metal-backed component (without a flange) is initially implanted and subjected to normal loading, these components may experience distraction between the component and the surrounding bone at inferior sites. Compressive stresses in the superior dome cancellous bone, however, will be substantial. If complete porous ingrowth is achieved, the superior dome compressive stresses will be reduced and substantial shear stresses created. In addition, high local bone stresses were found at the component rim. If bone ingrowth is achieved only in specific locations, stress transmission will be dictated by those locations and may differ markedly from the case of complete bone ingrowth. In the event that no porous ingrowth is achieved and a fibrous layer forms around the component, the interface stresses will be similar to those calculated for the natural hip. The addition of a flange to the rim of the cup will reduce the magnitude of the radial stresses transmitted to the cancellous bone superiorly and medially by directly transferring some of the load to the lateral wall of the pelvis. The flange will also help to relieve the high local stresses that are found at the component rim.