无牙颌息止位与总义齿垂直距离的关系

作者认为应该重新评价传统的以息止颌位的垂直距离作为总义齿修复出发点的作法,即以息止颌位的垂直距离减去咬合时的垂直距离等于(牙合)间隙的方法。因为在应用此法时,常遇到的问题是面部测量易出错及息止颌位的不恒定。作者报道了一项关于无牙息止颌位面部高度和戴新的全口义齿咬合位时面部高度关系的研究。     

换托纠正全口义齿偏[牙合]

全口义齿偏[牙合]表现为偏[牙合]侧上、下颌后牙同名牙尖相对,对侧后牙异名牙尖相对,下颌向对侧适当滑动时,可见义齿正中咬合紧密,而当下颌回到正中[牙合]位时则出现中线偏斜、咬合关系错乱现象。笔者尝试通过对义齿重换基托（以下简称换托）来纠正偏[牙合],取得了良好的效果：保留了原人工牙的解剖形态并避免了重做。现介绍如下：     

更换全口义齿制作法的探讨

当全口义齿使用数年后,常常由于义齿的老化、患者口腔组织的改变等原因需要重做,或患者要求根据旧义齿另做一副以备用,对这些患者更换新义齿,在操作方面应有所不同,尤其在人工牙排列和(牙合)关系的处理要恰当。 本文介绍一种更换全口义齿的方法,使新的义齿在人工牙的排列和颌位关系与旧义齿一致,易被病员所接受,获得良好效果。     

上颌全口义齿固位与稳定性的三维有限元分析

目的研究牙尖斜度、腭穹隆形状、人工牙排列位置对上颌全口义齿固位与稳定性的影响。方法应用三维有限元方法研究牙尖斜度、腭穹隆形状和人工牙排列位置对上颌全口义齿基托位移状况的影响。结果颊侧基托边缘区垂直向位移均为压向粘膜方向,使基托下沉的移位;后牙从牙槽嵴顶向颊侧移动,前牙唇向偏离牙槽嵴时,唇、颊侧基托边缘区位移增大;牙尖斜度为0°和10°时,基托后缘区垂直向位移、唇侧基托的垂直向和纵向位移均为背离粘膜方向,牙尖斜度大于等于20°时,基托后缘区和唇侧基托边缘区的垂直向位移变为压向粘膜方向。腭穹隆低平和腭穹隆高者位移较腭穹隆适中者大。结论牙尖斜度、腭穹隆形状、人工牙排列位置对上颌全口义齿的固位与稳定有明显的影响作用。选用牙尖斜度为22°～24°的人工牙有利于义齿的固位与稳定。     

全口义齿人工牙的选择与排列

选牙与排牙是全口义齿制作的关键步骤之一。前牙选择的要素包括人工牙的形态、大小和颜色。后牙则主要考虑型,一般包括三种类型:解剖式牙、半解剖式牙、非解剖式牙(例如舌向集中型牙)。排列前牙对于恢复患者唇部正常外形以及改善发音都有重要影响,应尽量避免左右牙齿过于对称而引起的"假牙面容"。后牙排列则侧重恢复咬合功能。全口义齿完成选牙和排牙后应进行临床试戴,目的是检查前牙美观是否满意、基托边缘是否合适、咬合是否良好等。     

全口义齿牙尖斜度与咀嚼效能和稳定性的研究

目的研究全口义齿人工牙的牙尖斜度与义齿咀嚼效能及义齿稳定性的关系,为义齿设计提供依据.方法首先采用解析几何的方法对全口义齿人工牙的牙尖斜度与咀嚼效能及稳定性之间的关系进行分析;然后选用同一品牌、同一规格3种牙尖斜度(0°、12°、33°)的人工牙后牙,用蘸印泥压印法统计各类人工牙的(牙合)面接触面积,并通过数学方法分析人工牙的(牙合)面接触面积与义齿咀嚼效能间的关系.结果牙尖斜度大者,咬切食物的分力大,但义齿受到的侧向分力也大;(牙合)面接触面积的大小顺序为33°牙＜12°牙＜0°牙,义齿行使功能时,人工牙的压强大小与(牙合)面接触面积成反比.结论使用牙尖斜度大的人工牙咀嚼效能高,但不利于义齿的稳定;牙尖斜度小的人工牙咀嚼效能低,但有利于义齿的稳定.     

上颌全口义齿设计的改变对固位的影响

本文目的是通过对义齿设计的少量改变,观察在模拟咀嚼运动时上颌全口义齿的固位情况。设计的改变包括:(1)咬(牙合)点的位置;(2)基托边缘厚度;(3)腭部基托的伸展。材料和方法:受试者为5个上颌无牙患者,牙槽嵴均中等度吸收,粘膜健康,颌关系正常,下颌至少残留10枚自然牙(包括切牙、尖牙和双尖牙)。取上颌功能性印模,唇颊沟作功能性伸展,腭部伸展至颤动线。     

换托纠正全口义齿偏

全口义齿偏表现为偏侧上、下颌后牙同名牙尖相对,对侧后牙异名牙尖相对,下颌向对侧适当滑动时,可见义齿正中咬合紧密,而当下颌回到正中位时则出现中线偏斜、咬合关系错乱现象.笔者尝试通过对义齿重换基托(以下简称换托)来纠正偏,取得了良好的效果:保留了原人工牙的解剖形态并避免了重做.现介绍如下:     

全口义齿(瓷牙)复制的一种简便方法

临床上常有已戴用多年全口义齿的患者 ,希望对已戴用习惯且自感满意的义齿重作一副 ,以备用或续用。对此类已戴用习惯又无其它问题的义齿 ,在重做时需特别考虑新义齿尽可能与旧义齿接近 ,包括咬合的高度、牙列在牙槽嵴上排列的位置(内外前后 )、基托的厚薄、边沿伸展、抛光面外形等。作者对临床中遇到的两例患者采用印模膏拓制旧义齿阴模来排牙、翻压基托蜡型的方法复制义齿获得满意的临床效果 ,报道如下 :1　材料与方法1.1　修复选用材料贺利氏通用型印模材 ,齿科蜡 (上齿厂 )、钉瓷牙 (选旧义齿同型号 ,上齿厂 )、模型石膏、牙合架等。1.2…     

全口义齿临床操作要点——细节决定成败

印模取得好不好是关系一副全口义齿最终修复效果的较重要的操作。首先要学会判断印模取得质量如何?部分医师不知道判断印模好坏的标准,常见取的不好的印模就进入下一步操作,直接影响下一步操作并最终影响义齿质量。选合适的托盘:(1)托盘形状、大小与患者口腔颌弓一致;(2)不合适的托盘可以修改;至合适为止;(3)临床常见问题是托盘过大,使印模边缘过度伸展。泡印模膏及采初印模:(1)水温要恒定;(2)印模膏软化后充分整塑,印模膏软硬度合适均匀有利于肌功能整塑;(3)印模膏量要放置合适,不要太多,也不能少,临床常见问题是印模膏量过多,影响肌功能整塑的质量,且边缘易伸展过度;(4)肌功能整塑:整塑要充分到位,反复检查及调整直到满意。二次藻酸盐取终印模:(1)印模材按水份比例调至均匀,流动性合适,否则影响印模质量;(2)肌功能整塑手法正确,整塑到位、合适;(3)下颌印模制取时不要大张口。学会判断印模质量好坏:(1)边缘伸展合适,肌肉系带缓冲合适,清晰;(2)边缘封闭区宽度一致,符合口内实际情况;(3)常见问题是伸展不够或伸展过度。确定颌位关系:(1)蜡堤弓形与颌弓一致;(2)蜡堤高度、厚度要符合要求。临床青年医师掌握较难,常见垂直距离过低和丰满度欠佳,要逐步学会面部外形观察法,使病人面容自然、对称、美观。水平颌位测定:学会掌握判定颌位正确的方法和判定手段、技术。用颌堤咬合时有力、位置重复准确、稳定是判断的一个依据。试排牙应注意检查以下问题:1、咬合关系好,咬合时重复率高、稳定、无翘动。2、美观符合要求,患者满意。3、覆牙合覆盖合适,有利于平衡牙合。常见问题:系带缓冲不够,边缘伸展过度影响系带、肌肉、粘膜和舌的运动,表现为张口时或运动时义齿脱位。常见问题:不明确调牙合(正中牙合、侧方牙合、前伸牙合)要达到什么样的标准?(1)正中牙合:后牙支持尖要均匀接触,咬合稳定,无翘动;(2)前伸牙合:下颌前伸时上颌义齿稳定无障碍;(3)侧方牙合:侧方运动时义齿稳定,无翘动及脱位;注意检查方法:可以用观察上颌义齿唇侧基托和舌系带处在做前后、侧方咬合时无移位和无唾液泡沫产生为判断依据。最后谈谈全口义齿设计问题:根据患者的实际情况,在检查阶段注意"有利于"和"不利于"义齿功能的先天条件,做好设计并贯穿于义齿修复、制作的各个环节,对获得较好的修复效果非常重要。常见临床医师忽视全口义齿设计,不重视按患者特点考虑,而仅按常规操作而导致义齿修复效果不佳,希望医师在进行全口义齿修复时从检查开始就有重视设计的理念,用设计指导制作才能提高全口义齿的修复疗效。     

人工牙排列位置对下颌全口义齿固位及支持组织的影响

采用ＣＴ－数字化仪－ＣＡＤ系统建立了下颌无牙颌骨及其义齿的３个三维有限元模型，探讨在Ｈｅ力，口周肌力作用下，下颌人工牙排列位置对义齿固位和支持组织应力分布的影响，并测量了１０例口周肌动力及传统型全口义 工牙排列位置的差异。结果表明；Ｈｅ力作用下，人工牙排列干剩余牙槽嵴顶及水平偏离槽嵴顶舌，颊侧３ｍｍ，对牙骨应力分布无明显影响，但后牙位于下颌骨外斜嵴区对支持组织有利；正中Ｈｅ时，磨牙排列于牙槽嵴顶颊     

Selection of occlusal scheme on the basis of pressure distribution on supporting structures under complete dentures

In case of making complete dentures, we have to consider not only denture stability but also the restoration of aesthetics and function such as mastication and speech. However these are contradictory theoretically from the point of view of denture stability, and it is very difficult to satisfy both requirements in the case of a patient who has poor upper and lower alveolar ridges. We investigated the effect of artificial posterior teeth form and occlusal scheme on the distribution of pressure on supporting structures under complete dentures during mastication with upper and lower edentulous simulators. In this report, a guideline for the selection of occlusal scheme for complete dentures, based on our previous investigations, is described. The occlusal scheme remarkably affected the distribution of pressure under simulated complete dentures, as shown by comparing the distribution of pressure using two different occlusal schemes:fully balanced occlusion and lingualized occlusion. However other factors such as posterior teeth form and position affect the distribution of pressure as well, and are related to each other. Therefore, not only occlusal scheme but also posterior artificial teeth form has to be considered, and the form of posterior teeth should be carefully and comprehensively decided when making complete dentures.     

A simplified approach to optimizing denture stability with lingualized occlusion

Occlusal prematurities are destructive and destabilizing influences in complete dentures. Unless denture bases are adequately and evenly stabilized, it is virtually impossible to properly equilibrate the occlusion. One reason is that all artificial teeth in a denture unit are physically bound into a single denture base and literally act as a single tooth. Therefore, a single point of occlusal prematurity disrupts the entire denture occlusion and negatively affects the denture base stability and retention, preventing proper equilibration. This article describes a step-by-step approach using an intraoral central bearing point tracing device and lingualized occlusion to achieve an effective and simplified equilibration.     

不同排牙方法对全口义齿修复影响的临床研究

目的 探讨不同的排牙方法对无牙颌患者满意度和全口义齿咀嚼效能的影响.方法 采用上颌排牙法、下颌排牙法和综合排牙法为10例无牙颌患者分别制作3副全口义齿.戴用3个月后,测试无牙颌患者对3种全口义齿的满意度,同时通过吸光度法测定咀嚼效率及咀嚼次数,比较三种排牙方法的全口义齿咀嚼效能的异同.结果 无牙颌患者在戴用3个月后对下颌排牙法和综合排牙法全口义齿的满意度均好于上颌排牙法义齿.本实验3组全口义齿中下颌排牙法和综合排牙法全口义齿的咀嚼次数和咀嚼效能无显著差异,但均好于上颌排牙法义齿.结论 下颌排牙法和综合排牙法的全口义齿排列的人工牙有利于无牙颌患者在咀嚼过程中稳定地使用义齿,提高咀嚼效能,而且无牙颌患者对下颌排牙法和综合排牙法的全口义齿也更满意.     

计算机辅助设计与快速成形技术辅助制作全口义齿的探讨

目的探索全口义齿计算机辅助设计（computer aided design，CAD）与快速成形技术辅助制作技术路线，并开发相关程序。方法用三维自动切层扫描仪获取人工牙外表面三维数据并建立人工牙三维图形数据库（可用于参数化定位）。用三维点激光扫描仪获取无牙颌石膏模型及骀堤表面的三维数据，利用模型关系定位器记录猞堤的颌间关系数据。基于Imageware 11软件探索全口义齿CAD技术路线，包括创建排牙线、人工牙定位标志点、定位坐标系以及基托构建线、控制线等，完成全口义齿包括人工牙列、基托组织面和磨光面外形以及全口义齿石膏阴模的完整三维设计，针对该路线编程，开发CAD软件平台。用快速成形技术制作全口义齿石膏阴模，手工插入人工牙并完成全口义齿的制作。结果确立了全口义齿CAD技术路线，通过编程开发了CAD软件平台，完成1例全口义齿的制作。结论利用自行开发的CAD软件可将教科书上的全口义齿排牙原则、基托设计原则和美学原则表达在CAD过程中，并在设计时应用猞堤的三维数据，实现了全口义齿的数字化、智能化和个性化的设计制作流程。     

数字化口腔修复（20）--数字化全口覆盖义齿的临床应用（附病例报告）

目的：利用计算机辅助设计与制造（ computer aided design／computer aided manufacturing,CAD／CAM）技术,制作数字化的全口覆盖义齿并评价其修复效果。方法：临床病例为上下颌各残余经根管治疗和金属根帽修复的两个残根的无牙颌患者,按照传统全口义齿的临床操作完成印模,哥特式弓记录轨迹,面弓转移牙合记录,上牙合架,再经过扫描牙合架上的模型,在CAD虚拟牙合架上完成虚拟排牙和虚拟咬合运动,CAM切削基托蜡型和成品人工牙,最后将人工牙安放在切削基托蜡型咬合面的基底上。经过传统试排牙和三维数字化试排牙后,患者满意后,常规充胶,完成全口覆盖义齿制作并戴牙。结果：数字化全口覆盖义齿的固位和稳定良好,美观,能够正常行使咀嚼功能。结论：数字化全口覆盖义齿与传统的全口覆盖义齿比较,具有简单数字化排牙工艺,牙合设计精确,形成的牙合曲线完美,基托厚薄一致,患者适应期短的优点,是今后全口义齿制作的发展方向。     

Frenectomy for improvement of a problematic conventional maxillary complete denture in an elderly patient: a case report

Maxillary labial and buccal frena are considered as normal anatomic structures in the oral cavity. However, they may exist intraorally as a thick broad fibrous attachment and/or become located near the crest of the residual ridge, thus interfering with proper denture border extension resulting in inferior denture stability, retention and overall patient satisfaction. This case report highlights the importance of clinical examination and treatment planning which may mandate preprosthetic surgery prior to fabrication of a new conventional complete denture. Adequate patient satisfaction with conventional complete dentures can be significantly increased after frenectomy.     

Complete denture fabrication using piezography and CAD-CAM: A clinical report

To provide maxillary and mandibular complete dentures for a patient with severe ridge resorption, the denture space was recorded using the piezography technique. After the piezographic space was scanned, a virtual tooth arrangement and festooning were performed within the space using computer-aided design software. The denture bases were milled from a polymethylmethacrylate resin block using computer-aided manufacturing, and commercially available denture teeth were bonded with resin adhesive. Using the piezography technique described, physiologically appropriate complete dentures were fabricated based on the neutral zone concept.     

计算机辅助全口义齿人工牙排列的研究

目的　研究开发一套计算机辅助全口义齿设计 (computeraidedcompletedenturedesign ,CACDD)系统。方法　经过对无牙颌模型、人工牙及具有正中关系位的上下托的三维 (3D)测量、数据处理与建模等环节后 ,根据全口义齿人工牙排列的原则和要求进行排牙。运用仿射和投影变换技术调整牙关系。结果　①生成了具有正中关系位的上、下颌虚拟基托 ,其数学模型为双 3次B样条曲面。②实现了全口义齿人工牙的计算机辅助排列和全口义齿的 3D显示。结论　该系统为计算机辅助全口义齿设计和教学提供了可行的工具     

Occlusal schemes of complete dentures--a review of the literature

Occlusal scheme is defined as the form and the arrangement of the occlusal contacts in natural and artificial dentition. The choice of an occlusal scheme will determine the pattern of occlusal contacts between opposing teeth during centric relation and functional movement of the mandible. With dentures, the quantity and the intensity of these contacts determine the amount and the direction of the forces that are transmitted through the bases of the denture to the residual ridges. That is why the occlusal scheme is an important factor in the design of complete dentures. Three occlusal schemes are viewed in this review: bilateral balanced occlusion, monplane occlusion, and linear occlusion scheme. Each scheme represents a different concept of occlusion. Comparisons between these schemes are also reviewed and analyzed. The reasoning underlying the bilateral balanced occlusion scheme is that stability of the dentures is attained when bilateral contacts exist throughout all dynamic and static states of the denture during function. Anatomic teeth are used: the upper anterior teeth are set to satisfy aesthetics, and the posterior teeth are arranged in a compensatory curve and a medial curve. This scheme is adequate for well developed residual ridges, with skeletal class I relation. With highly resorbed residual ridges, the vectors of force that are transmitted through anatomic cusps will dislodge the lower denture and thus impair the comfort and efficiency of mastication experienced by the patient. In order to accommodate to the special needs posed by highly resorbed residual ridges and skeletal relations that are not class I, the monoplane scheme of occlusion was designed. This scheme consists of non anatomic (cuspless) teeth, which are set so that the anterior teeth provide the aesthetics, the premolars and the first molars are used for chewing, and the second molars do not occlude (although sometimes they are specifically used to establish bilateral contacts in lateral movements). Linear occlusion scheme occludes cuspless teeth with anatomic teeth that have been modified (bladed teeth) in order to achieve linear occlusal contacts. Linear contacts are the pin-point contacts of the tips of the cusps of the bladed teeth against cuspless teeth that create a plane. The specific design of positioning upper modified teeth on the upper denture and non anatomic teeth on the lower one is called lingualized occlusion. It is characterized by contacts of only the lingual (palatinal, to be more accurate) cusps of the upper teeth with the lower teeth. The lingualized occlusal scheme provides better aesthetics than the monoplane occlusion scheme, and better stability (in the case of resorbed residual ridges) than bilateral occlusion scheme of anatomic teeth. The results of studies that compared different occlusal schemes may well be summarized as inconclusive. However, it does seem that patients preferred anatomic or semi-anatomic (modified) teeth, and that chewing efficiency with anatomic and modified teeth was better than with non anatomic teeth. Similar results were found in studies of occlusal schemes of implant-supported lower dentures opposed by complete upper dentures. Conclusion: There isn't one occlusal scheme that fits all patients in need of complete dentures, in fact, in many cases more than one occlusal scheme might be adequate. Selection of an occlusal scheme for a patient should include correlation of the characteristics of the patient with those of the various occlusal schemes. The characteristics of the patient include: height and width of the residual ridge, aesthetic demands of the patient, skeletal relations (class I/II/III), neuromuscular control, and tendency for para-functional activity. The multiple characteristics of the occlusal schemes were reviewed in this article. Considering all of those factors in relation to a specific patient, the dentist should be able to decide on the most suitable occlusal scheme for the case.