具有组织终止带的下颌无牙颌印模技术初探

目的 初步确定并验证一种适用于下颌四类无牙颌的印模技术。方法 对20名四类无牙颌志愿者分别使用常规印模技术和具有组织终止带的印模技术取下颌印模,对比其将松软组织推开的能力以及相应暂基托的舒适度,随机选用其中一个模型完成总义齿制作,检查并记录总义齿初戴时的组织密合度及患者的复诊次数。结果 采用配对t检验显示：两组推开松软组织的能力间差异有统计学意义,舒适度评价差异无统计学意义;采用独立样本t检验显示：两组总义齿组织密合度间差异无统计学意义,复诊次数间差异有统计学意义。结论 具有组织终止带的下颌印模技术可以有效地推开松软组织,虽不能提高初戴的舒适性和基托的组织密合度,但是却有效地减少了患者的复诊次数。     

压力印模法制取无牙颌印模的临床研究

４８例无牙颌患者中２５例牙嵴条件差者，用压力印模法制取印模，其余牙嵴条件好者用常规印模法取模。复查４３例，对二者戴牙效果作了比较，并进行了模型分析。采用压力印模法者，戴牙后复诊改率低于常规印模法者，具有较好的戴牙效果。     

无牙颌印模的围模灌注技术

正确的围模操作是获得高质量无牙颌终模型的前提。围模将在印模边缘形成一个足够宽度的肩台,可以完整保存终印模的边缘精细表面形态,同时形成一个盒装结构以容纳超硬石膏材料,保证终模型的强度。围模方法包括红蜡片围模灌注方法与抛光砂围模灌注方法。不管哪种方法,首先需要在终印模边缘下方3 mm处画线或者涂抹粘接材料,以确定围模的正确位置。终模型完全硬固后,应在模型底座上制作多条复位槽以方便后续的二次上架,制作方式包括利用成品底座或者是直接打磨出复位槽。     

定位垫在无牙颌印模制取中的应用

在无牙颌印模的制取中,常会出现终印模薄厚不均的情况,影响印模的准确性。我们采用在个别托盘组织面上粘贴定位垫的方法,使印模厚度更加均匀,效果良好。报告如下:1材料与方法1.1一般资料选择2004年以来就诊的无牙颌患者21例,其中男8例,女13例,年龄55~94岁,平均65.8岁。1.2方法1     

无牙颌口内数字化印模技术可行性的初步探究

目的：通过对上颌无牙颌口内数字化印模与间接数字化印模精度进行对比,探讨采用数字化印模技术进行无牙颌印模的可行性。方法：随机选取10例上颌牙列缺失的患者,使用TRIOS口内扫描仪直接获取患者上颌解剖式印模,标记为直接印模组（DP）;同时使用传统方法制作有孔的个别托盘,使用轻压力来获取同一患者的上颌无牙颌解剖式印模,灌注模型后使用TRIOS口内扫描仪和3shape810模型扫描仪分别扫描其石膏模型,标记为口外印模组（OP）和间接印模组（IP）。将三组数字化印模两两导入GeomagicWrap2015软件中,进行模型配准和3D拟合分析。以IP组作为参照,采用单因素方差分析和配对t检验分别进行组内和组间数据分析,比较TRIOS三代扫描仪扫描口内及模型的黏膜变形量大小。结果：TRIOS三代口内扫描仪在临床上可以有效快速的扫描上颌无牙颌,其扫描口内及模型相对于模型扫描仪扫描模型的精度均具有统计学差异（P<0.05）,口内直接扫描的误差为0.312±0.085 mm,口外间接扫描模型的误差为0.125±0.056 mm。误差主要集中于无牙颌边缘、腭中缝和后堤区等区域,牙槽嵴及上颌硬区处偏差较小...     

数字化印模在无牙颌中应用的研究进展

数字化印模是一种高效、便捷的新兴印模技术,近年来在固定冠、种植牙,可摘局部义齿中都展现了良好的准确度以及临床疗效,同时简化了临床诊疗的繁琐流程,提高了患者舒适度.无牙颌印模制取一直是临床诊疗的关键与难点,数字化印模在无牙颌患者修复中的应用逐渐增多.该文将从无牙颌数字化印模的分类、准确度研究以及临床扫描策略进行综述,为无...     

无牙颌的解剖标志与全口义齿印模

精确的全口义齿印模是成功镶复全口义齿的关键。在牙槽嵴条件较好时,印模的边缘位置较容易确定,印模的制取相对容易。但是因重度牙周疾病或长期配戴不合适的义齿而造成牙槽骨严重吸收时,牙科医生可能对制取印模时如何正确伸展义齿边缘感到困惑。众所周知,义齿基托范围越宽,义齿     

组织调节剂在无牙颌功能性印模中的临床研究

目的：将组织调节剂的重衬义齿技术应用于无牙颌功能性印模技术中,评价其对下颌牙槽嵴严重吸收的无牙颌病例临床修复效果的影响。方法：选择36例下颌牙槽骨广泛吸收的无牙颌老年患者,其主诉为经反复修改后的原义齿仍然有压痛（17名）和易脱位（34名）,要求重做义齿。印模时在义齿蜡型暂时基托组织面涂布组织调节剂,嘱患者作正中咬合,并以主动方式完成印模边缘整塑,修整后再在组织面用藻酸盐印模料取模,以此作终印模。结果：36例患者戴用重新制作的义齿后咀嚼疼痛得到解决,义齿固位显著提高。结论：将组织调节剂重衬义齿技术应用于功能性印模中,能预防性地避免印模不准确造成的咀嚼疼痛和固位不佳等问题。     

无牙颌两种印模方法的数字化模型偏差分析

目的:利用数字化扫描技术和逆向工程软件探索上颌无牙颌的黏膜变化,比较不同取模方法下无牙颌模型的差异.方法:随机抽取20名上颌无牙颌患者,通过两种不同的方法获取其上颌印模:使用有孔托盘和藻酸盐材料取传统解剖式印模,以及使用无孔托盘和硅橡胶材料取压力式印模.然后使用口外扫描仪对所有印模进行扫描并转化为数字模型.对同一患者的...     

牙种植义齿修复开窗式印模的护理配合

目的探讨牙种植义齿修复开窗式印模的护理配合。方法34例牙种植体修复时选择开窗式印模的患者,采用统一规范的操作程序,观察二次印模的精确性,转移体有无松动、移位,义龈制作是否标准,翻制的石膏工作模型是否清晰准确,替代体有无松动。结果除2例需要重新印模外,32例印模光滑、清晰、元气泡、义龈制作标准,翻制的石膏工作模型清晰完整,替代体无松动。成功率94．12％。结论熟悉医生的操作流程,掌握印模材料及义龈制作材料的性能、操作方法,才能做到护理配合规范、熟练、主动,取得精确的模型。     

不同印模方式对松软牙槽嵴印模精度的比较研究

目的：比较3种不同印模方式对无牙颌松软牙槽嵴印模精度的影响。方法：纳入5名松软牙槽嵴患者,分别采用常规法、缓冲法、开窗法制取印模,灌注终模型。采用口内光学扫描仪获取口内及各个终模型上相应松软牙槽嵴区域的光学印模,导入 Geomagic Qualify 2013软件进行分析,分析口内松软牙槽嵴的光模与各个终模型上相应区域光模的拟合程度,比较3种印模方式的印模精度。结果：5位患者的光学印模拟合图及软件分析所得3D 偏差值（SD、Mean ＋、Mean －）的方差显示,常规法偏差值最大,缓冲法其次,开窗法最小。结论：对于松软牙槽嵴的无牙颌开窗印模方式可提高印模精度。     

松软牙槽嵴无牙颌的全口义齿修复

目的 探讨松软牙槽嵴无牙颌的全口义齿修复要点.方法 选择松软牙槽嵴无牙颌患者31例.修复前询问患者义齿使用习惯,检查口腔及旧义齿情况,进行必要的修复前手术,择期重新修复.在修复后6个月、1年、2年后复查,根据病历记录检查患者口腔和义齿情况是否有改变.结果 义齿修复后的2年中,牙槽嵴的松软范围没有明显扩大,义齿使用效果良好.结论 伴有松软牙槽嵴的无牙颌全口义齿修复时,应该注重印模的准确性、前牙与牙槽嵴顶的位置、前牙的覆(牙合)与覆盖,指导患者正确使用义齿并定期复查,可取得良好治疗效果.     

Current concepts and techniques in complete denture final impression procedures

PURPOSE: In 2001, a survey of U.S. dental schools was conducted to determine which concepts, techniques and materials are currently prevalent in the teaching of final impression procedures for complete dentures in the predoctoral clinical curriculum. MATERIALS AND METHODS: The questionnaire was mailed to the chairperson of the prosthodontic/restorative departments of 54 U.S. dental schools. Of these, 44 schools returned the completed survey resulting in a response rate of 82%. RESULTS: Results from this survey show that the majority of schools (71%) teach the selective-pressure technique for final impression making; the majority of the schools (64%) use modeling plastic impression compound for border molding the final impression tray; 39% of the schools do not place vent holes in the final impression tray, 30% of schools place more than one hole and 27% place one hole only; the majority of the schools (98%) are using custom trays for final impressions. Ninety-eight percent of the schools are border molding the custom tray and 70% of schools are using a visible light-cured (VLC) composite resin material to make the trays. Thirty-six percent of the schools are teaching the Boucher impression technique and 34% are teaching the modified Boucher impression technique. CONCLUSIONS: Predoctoral clinical complete denture educational programs agree on many aspects of final impression making, however, there is variability in their teachings regarding the impression philosophy and the materials used.     

A laboratory study of dimensional changes for three elastomeric impression materials using custom and stock trays

Clinical success of fixed prosthodontic procedures is dependent in part upon the dimensional accuracy of elastomeric impression materials and impression procedures. Three elastomeric impression materials were used in custom and stock trays to determine the accuracy of impressions taken from an experimental stainless steel model representing premolar and molar bridge abutment preparations. Horizontal and vertical individual abutment and interabutment dimensions were measured on die stone replicas, and the measurements compared with those obtained from stainless steel master models. The results of this study demonstrate polysulphide is the least accurate impression material for both vertical and horizontal individual abutment dimensions. However, for interabutment horizontal dimensions, no statistical differences were noted between impression material types when using a custom tray. Stock trays produced unreliable results for all the materials tested.     

The epidemiology of edentulous atrophic mandibular fractures in Europe

IntroductionThe objective of the present study was to assess the demographic variables, causes, and patterns of edentulous atrophic fractures of the mandible managed at several European departments of oral and maxillofacial surgery. The results of this multicenter collaboration over a 10-year period are presented.MethodsThe data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between January 1, 2008, and December 31, 2017 were recorded: gender; age; voluptuary habits; comorbidities; etiology; fracture sites; synchronous body injuries; atrophy of the mandible according to Luhr classification; eventual type of treatment; timing of the eventual surgery; length of hospital stay.ResultsA total of 197 patients (86 male and 111 female patients) with 285 mandibular fractures were included in the study. Mean age of the study population was 75 years. Statistically significant associations were found between Luhr classes I – II and condylar fractures on one hand (p < .0005), and between Luhr class III and body and parasymphyseal fractures on the other hand (p < .05). Finally, 135 patients underwent open reduction and internal fixation, 56 patients did not undergo any intervention, and 6 patients underwent closed reduction. No statistically significant association was observed between treatment, timing of treatment, comorbidities, and concomitant injuries.ConclusionsThe management of edentulous atrophic mandibular fractures remains challenging. Treatment decisions should continue to be based on the clinician's previous experience and on the degree of bone resorption in edentulous mandible in relation to fracture subsites.     

An alternative and simplified technique for the impression of completely edentulous ridges

When a patient's original denture is in harmony with the anatomicand physiologic limitations of the oral structures, itcan be used a an impression tray for making a new denture. This article describes this alternative technique and illustrates the steps involved to demonstrate the denture adaptation and provide patient satisfaction.