戴用可摘义齿的微生态学问题

微生态学是研究正常微生物群与宿主相互关系 ,微生态环境生态平衡和生态失调、以及建立生态调整和生态防治的一门新的学科。戴用可摘义齿可能引起口腔微生态环境的改变、促进菌斑的沉积 ,导致龋病和牙周病发病率增加等 ,在口腔修复学中已成为一急待解决的临床问题 ,本文就戴用可摘义齿的微生态学问题作一综述。1　正常口腔的微生态环境由于口腔的特殊环境 ,如有适宜的温度、湿度、营养源以及复杂的结构和理化性质等 ,给口腔内各种微生物的生长、繁殖、定居提供了良好的环境和条件 ,这些微生物在口腔不同部位栖息、共存 ,竞争和拮抗 ,与宿主…     

可摘局部义齿基牙易发龋坏部位致龋菌的检出比较

通过对戴入可摘局部义齿后基牙易发龋坏部位的早期细菌组成的测定,探讨可摘局部义齿与基牙龋坏之间的潜在关系。观察１２个６活动桥的２４颗基牙,其中５、７各１２颗。病人平均年龄２５５岁。采取基牙靠缺隙侧邻面１／３区域的菌斑。采用细菌培养技术,持续观察了３个月,测定了菌斑细菌的组成。结果发现,变形链球菌的检出率在实验中呈逐渐上升趋势,且在牙位７上的检出率比在牙位５上的检出率高。结论戴用可摘局部义齿造成了口腔微生态环境的改变,促进了某些致龋细菌的生长,成为基牙发生龋坏的潜在因素     

两种可摘局部义齿戴用前后语音效果的对比研究

目的：对上颌肯氏I类牙列缺损可摘局部义齿戴用前后的临床语音适应效果做出客观评价。方法：对30例上颌肯氏I类牙列缺失患者在义齿初戴前、初戴时、初戴后的1、2、4、8用语音变化规律进行分析。结果：辅音／j／：在塑料组,在初戴后2．4、8周与初戴时F2有统计学差异（P〈0．05）;在初戴时与初戴前相比F2也有统计学差异（P〈0．05）。初戴后1周也有统计学差异（P〈O．05）;两组同一时间内比较,/j/的F2在初戴时有统计学差异（P〈0．01）。／sh／音：在初戴时与初戴后2、8周F1有统计学差异（P〈0．05）。/z／音：在塑料、铸造两组中,F1、F2在初戴前、后2、4、8周均有统计学差异（P〈0．05）。结论：可摘局部义齿基托厚度主要影响的发音部位是硬腭前部,在临床上,减少硬腭区基托厚度,对临床修复有较好的指导意义。     

整体铸造支架式可摘局部义齿添加人工牙的临床修理效果

目的：探讨整体铸造支架式可摘局部义齿添加人工牙的修理体会。方法：对240例佩戴整体铸造支架式可摘局部义齿的患者进行义齿添加人工牙修理,比较修理前后视觉模拟（VAS）评分、咀嚼功能及1年后人工牙的磨耗程度。结果：修复后VAS评分明显低于修复前,两者比较差异有统计学意义（P〈0.05）,但牙槽骨吸收距离未见明显差异（P〉0.05）。经过修复后义齿的固位稳定及咀嚼情况较修复前明显好转,在随访1年后,人工牙大多有轻到中度的磨耗,磨耗后出现23例颌位垂直距离缩短及2例下颌前移及偏移。结论：设计合理的支架连接体,并且尽量作添加人工牙和卡环的修理,可以延长义齿的使用寿命。     

固定-可摘联合义齿对牙周病合并牙列缺损的修复效果

目的:观察固定-可摘联合义齿应用于牙周病伴牙列缺损修复效果,探讨其临床价值。方法:选择本院于2013年1月-2014年1月收治的符合牙周病伴牙列缺损诊断标准60例患者作为研究对象,按照数字法分为两组,每组30例,对照组采取可摘夹板式活动义齿修复,观察组给予固定-可摘联合义齿修复,两组患者均随访18个月,比较两组患者疗效。结果:戴义齿18个月观察组咀嚼效率(55.4±3.8),显著高于对照组(50.1±3.6),差异具有统计学意义,P0.05。观察组临床疗效显著优于对照组,差异具有统计学意义,P0.05。观察组戴用义齿后基牙拔除情况显著优于对照组,差异具有统计学意义,均P0.05。结论:固定-可摘联合义齿应用于牙周病伴牙列缺损修复效果较佳,具有重要临床价值。     

口腔微生态的研究进展

口腔微生物与人体始终处于动态生态平衡状态,对于维护人体的健康发挥重要的作用,也与多种口腔疾病的发生发展有密切关系.随着现代科学技术的发展,越来越多的新技术、新方法用于口腔微生态领域的研究,这使得人们对口腔微生态的认识不断深入.以下将从口腔微生态的组成、口腔微生态与机体的关系及其研究方法三个方面简要介绍近年来口腔微生态的相关研究进展.     

血链球菌与口腔微生态的关系

血链球菌与口腔微生态的关系大连医科大学微生态学研究所大连１１６０２７宋晓波口腔中的许多微生定居物与宿主之间保持着一种和谐共生关系——即临床健康状态。由于这些微生定居物以充足的数量占据着口腔各个生态位,它们对潜在的致病菌起着有效的防御功能〔１〕。血链球...     

口腔微生态失衡导致口腔异味的研究

目的介绍口腔微生态失调与口腔疾病的关系,口腔疾病出现口腔气味异常的机制。综合分析口腔微生态与口腔健康的研究动态及意义。展望口腔微生态调整在口腔疾病治疗中的作用研究,尤其在消除口腔异昧的积极作用。方法由第一、二作者应用计算机通过pubmed检索NCBI数据库1992年至2007年相关文献,检索词为“Micro ecology”,限定语言种类为“English”;同时检索CNKI全文数据库、维普全文数据库1995年至2007年相关文献,检索词为“微生态”,限定语言种类为中文。纳入标准：文章内容与口腔微生态相关的研究、以及在口腔疾病研究领域有关。排除标准：较陈旧的文献和重复研究。结果共收集到106篇相关文献,21篇文献纳入本文,其中,19篇为综述和述评类文献,19篇为中文杂志,2篇为外文杂志。结论致病菌大量生长繁殖,口腔微生态失调,菌斑内微生物之间以及机体与菌斑之间相互作用分解蛋白产生硫化物,这些代谢产物包括H2S、CH3SH、CH3SCH3、吲哚、甲基吲哚、挥发脂肪酸和聚胺等发出刺激性气味,产生口腔异味。治疗口腔异味应该考虑平衡口腔微生态,调整口腔菌群。口腔异味的治疗又有利于口腔菌群平衡。提示我们治疗口腔疾病应该考虑口腔微生态平衡。     

口腔微生态失衡导致口腔异昧的研究

目的介绍口腔微生态失调与口腔疾病的关系,口腔疾病出现口腔气味异常的机制。综合分析口腔微生态与口腔健康的研究动态及意义。展望口腔微生态调整在口腔疾病治疗中的作用研究,尤其在消除口腔异昧的积极作用。方法由第一、二作者应用计算机通过pubmed检索NCBI数据库1992年至2007年相关文献,检索词为“Micro ecology”,限定语言种类为“English”;同时检索CNKI全文数据库、维普全文数据库1995年至2007年相关文献,检索词为“微生态”,限定语言种类为中文。纳入标准：文章内容与口腔微生态相关的研究、以及在口腔疾病研究领域有关。排除标准：较陈旧的文献和重复研究。结果共收集到106篇相关文献,21篇文献纳入本文,其中,19篇为综述和述评类文献,19篇为中文杂志,2篇为外文杂志。结论致病菌大量生长繁殖,口腔微生态失调,菌斑内微生物之间以及机体与菌斑之间相互作用分解蛋白产生硫化物,这些代谢产物包括H2S、CH3SH、CH3SCH3、吲哚、甲基吲哚、挥发脂肪酸和聚胺等发出刺激性气味,产生口腔异味。治疗口腔异味应该考虑平衡口腔微生态,调整口腔菌群。口腔异味的治疗又有利于口腔菌群平衡。提示我们治疗口腔疾病应该考虑口腔微生态平衡。     

吸烟者血液微生态改变的实验观察

吸烟者血液微生态改变的实验观察北京三○九医院检验科北京１０００９１李洪敏,王枫吸烟对人体的危害,至今仍不能引起人们的重视,我们运用血液流变学的方法,对吸烟者的血液进行了分析,实验证实了吸烟者的血液微生态环境改变十分明显,对人类的身体健康是十分不利。现...     

Maxillary complete denture movement during chewing in mandibular removable partial denture wearers

Objectives: To evaluate the pattern of maxillary complete denture movement during chewing for free‐end removable partial dentures (RPD) wearers, compared to maxillary and mandibular complete denture wearers. Materials and methods: Eighteen edentulous participants (group I) and 10 volunteers with bilateral posterior edentulous mandibles (group II) comprised the sample. Measures of mean denture movement and its variability were obtained by a kinesiographic instrument K6‐I Diagnostic System, during the mastication of bread and a polysulphide block. Data were analysed using two‐way anova (α = 0.05). Results: Upper movement during chewing was significantly lower for group II, regardless of the test food. The test food did not influence the vertical or lateral position of the denture bases, but more anterior dislocation was found when polysulphide blocks were chewed. Group II presented lower intra‐individual variability for the vertical axis. Vertical displacement was also more precise with bread as a test food. Conclusion: It can be concluded that mandibular free‐end RPD wearers show smaller and more precise movements than mandibular complete denture wearers.     

Effect of oral hygiene education and motivation on removable partial denture wearers: longitudinal study

Objectives: The purpose of this study was to determine the effect of two different preventive oral hygiene education and motivation programmes on the plaque and gingival index, as well as denture hygiene of patients provided with removable partial denture (RPD) during a 12‐month follow‐up. Material and methods: A total of 53 partially edentulous patients were recruited for this study. The presence or absence of plaque and gingival bleeding by gentle probing was scored on all tooth surfaces at the preliminary visit. The plaque and gingival indexes were measured using the Löe index. Following treatment, the patients were randomly divided into three groups. In Control Group I, subjects were instructed to continue their personal oral hygiene routine. In Group II, participants were given verbal instructions and a self‐educational manual on oral hygiene without illustrations. In Group III, oral hygiene guidance was delivered using a combination of verbal instructions and a self‐teaching manual. To evaluate the effect of the different modes of instruction, the presence or absence of plaque and gingival bleeding was scored on all tooth surfaces (day zero examination) and re‐examined 7, 15 and 30 days, 3, 6 and 12 months following RPD placement. The state of denture hygiene was evaluated 7, 15 and 30 days and 3, 6 and 12 months following rehabilitation. Parametric statistics was applied to dental plaque and gingival indexes. For accumulation of plaque and calculus on the RPD, non‐parametric statistic was applied. Results: The frequency of plaque found during the preliminary visit was higher than that found in the other periods. With regard to gingival index, significant difference was found between the preliminary visit examination and other periods. There was a significant difference in the plaque accumulation on the denture surface between groups I and III. Conclusion: The different methods of oral hygiene instruction used in this study indicate that the type of education was not of significant importance.     

Zirconia-based dental crown to support a removable partial denture: a three-dimensional finite element analysis using contact elements and micro-CT data

Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (μCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core – M_Au; zirconia core – M_Zi) and the quality of the veneer/core interface (complete bonded – M_Zi; incomplete bonded – M_Zi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σ_max) and von Mises equivalent (σ_vM) stresses were obtained. The σ_max (MPa) for the bonded condition was similar between gold and zirconia cores (M_Au, 0.42; M_Zi, 0.40). The incomplete bonded condition (M_Zi-NL) raised σ_max in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σ_vM increased up to 270% in the M_Zi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface.     

Use of resin‐bonded extracoronal attachments with removable partial denture: case report

doi:10.1111/j.1741‐2358.2009.00298.x
Use of resin‐bonded extracoronal attachments with removable partial denture: case report Introduction: Resin‐bonded extracoronal attachments may be indicated for the abutment teeth of removable partial dentures, especially for anterior teeth when a cingulum rest must be provided. This type of treatment has a series of advantages such as minimal tooth reduction, supragingival margins, favourable stress distribution, and improved aesthetic appearance. Objective: To report a clinical case of oral rehabilitation using a combination of resin‐bonded extracoronal attachments joined by a Dolder bar with a removable partial denture. Case report: A 60‐year‐old male patient with only the canines in the maxillary arch was restored with a combination of resin‐bonded extracoronal attachments joined by a Dolder bar and a removable partial denture. Conclusion: Dentures with resin‐bonded extracoronal attachments can have a number of advantages over traditional clasp‐retained removable partial dentures.     

Partial edentulism and removable partial denture design in a dental school population: a survey in Greece

Gerodontology 2011; doi: 10.1111/j.1741‐2358.2010.00382.x Partial edentulism and removable partial denture design in a dental school population: a survey in Greece Objectives: To investigate the pattern of partial edentulism and the most frequent designs of cobalt‐chromium removable partial dentures (RPDs), constructed at the Dental School of Athens, Greece. Methods and materials: Five hundred and fifty‐three patients, between 42 and 81 years old, mostly males, treated by undergraduate dental students, were included. The survey was based on visual evaluation of master casts and work authorisation to dental technicians. Aspects examined were: Kennedy Classification, modification areas, major connectors, clasping, placement of rest seats and indirect retention. Results: Kennedy Class I was the most common encountered in the maxilla (50.5%) and in the mandible (70%). The most frequent major connectors were the lingual bar (92.6%) and the U‐shaped palatal strap (54%). The most common clasp was the Roach (69.2%) in Class I and Class II. In Class III and IV, the most common was the occlusally approaching clasp (55% and 70%). The most frequent location of the rest was mesial of abutment teeth. On the average, 39.5% of Class I RPDs and 58.6% of Class II RPDs had indirect retainers. Conclusion: A combination of the two major philosophies of RPD design (biomechanical and hygienic) was evident in the RPDs examined in our study.     

Prevalence of removable partial dentures users treated at the Aracatuba Dental School-UNESP

doi: 10.1111/j.1741‐2358.2012.00653.x
Prevalence of removable partial dentures users treated at the Aracatuba Dental School – UNESP Objectives: The aim of this study was to evaluate the frequency of removable partial dentures (RPD) at the Aracatuba Dental School. Methods: The study was conducted by analysing 412 clinical history of patients attended at the RPD clinics in the period from 2000 to 2007. Results: 412 charts were analysed: 148 (35.9%) men and 264 (64.1%) women. The mean age was 53.8 years (men) and 52.4 years (women). A total of 556 dentures were made; of these, 233 (41.90%) were maxillary and 323 (58.09%) were mandibular dentures. The most frequent Kennedy classification found was Class III (maxilla) and Class I (mandible). In the maxilla, 55% (126) of the major connectors were of the anterior–posterior palatal bar, while in the mandible, 64% (202) were the lingual bar. As regards the claps, 401 were circumferential and 318 were bar claps. Conclusion: The mean age of the patients was 52.9 years with higher prevalence of female patients; the most frequent Kennedy’s classification was Class I in mandible and Class III in maxilla; the most common major connector was anterior–posterior palatal bar for maxilla and lingual bar for mandible; the circumferential clasps were the most common retainer used in both jaws.     

染尘染毒大鼠呼吸道微生态的变化

目的探讨大气混合污染物对呼吸道微生态影响的机制,为预防大气污染对机体健康的损害提供理论依据。方法采用模拟实际大气污染方法,对Wistar大鼠进行染尘染毒,制备大气污染物动物模型,研究大鼠口咽部菌群染尘染毒前后的变化。结果染尘染毒的Wistar大鼠动物模型口咽部微生态发生改变(P<0.05)。染尘染毒后与染尘染毒前相比致病菌如中间葡萄球菌、猪链球菌、乙型链球菌等检出率明显增高(P<0.05)。染尘染毒前后自身比较,厌氧细菌菌群密度有明显增加(P<0.05),随着染尘染毒时间的延长,细菌的密度呈上下波动,表现出代偿状态。且需氧菌密度的变化较为明显(P<0.01)。结论大气污染可导致大鼠口咽部细菌密集度增高、致病菌增加以及细菌量的变化,呼吸道微生态改变可作为大气污染对机体危害的敏感指标。     

Effects of denture maintenance on satisfaction levels of Taiwanese elderly using removable partial dentures: a pilot study

doi: 10.1111/j.1741‐2358.2011.00500.x
Effects of denture maintenance on satisfaction levels of Taiwanese elderly using removable partial dentures: a pilot study Objective: The aim of this study was to evaluate the correlation between patient satisfaction with removable partial dentures and denture maintenance by patients, including regular application of denture adhesives and cleansers. Background: The success of removable partial dentures depends on patient satisfaction with dentures and their regular denture maintenance. Materials and methods: Demographic information, the Oral Impacts on Daily Performance (OIDP) indicator and details of denture maintenance (including the use of denture cleansers and adhesives) were collected from 193 (41.5% men and 58.5% women) participants by using questionnaires. A dentist performed oral examinations to evaluate denture function according to the OIDP items photographically and recorded the number of remaining teeth and Kennedy’s classification. Results: Most participants were satisfied with their removable partial dentures and tended to have higher satisfaction levels than the dentist’s estimation. Further, those using denture adhesives and cleansers had higher satisfaction levels than those not using such denture maintenance. Conclusions: Appropriate education regarding denture use is important because regular denture maintenance by patients affects their degree of satisfaction with dentures, as well as the dentist’s skill and the patient’s oral condition. Dentists could use this information to predict the potential success of dentures.     

The masticatory handicap of wearing removable dentures in elderly men

Objective: This study aimed at describing the masticatory handicap of wearing removable dentures measured by some masticatory tests and the intake of hard and soft foods. Materials and methods: The subjects were participants in a comprehensive health examination of 67–68‐year‐old men living in Malmö, Sweden. Four hundred eighty‐three men took part in a clinical oral examination which recorded the number of teeth and removable dentures. One hundred and one had complete dentures in both jaws and 131 had removable partial dentures in different combinations. Masticatory tests used almonds to record the number of stokes to the first swallow, and two‐coloured chewing gums for recording bolus kneading and shaping. A nutritionist paid a home visit to assess dietary habits including the consumption of hard and soft foods. The data could be split into groups of different tooth and denture situations which were large enough to enable statistical analysis to be carried out. The results of a regression analysis of the group with different numbers of natural teeth (NT) and no removable dentures could be used as a reference for correlation with the masticatory capacity of removable denture wearers. Results: Number of strokes to the first swallow revealed no masticatory limitations of wearing removable dentures, while chewing gum colour‐mixing and shaping revealed more differentiated impairments equivalent to the function of five to 16 teeth in a remaining natural dentition. Hard food intake for the removable denture groups was comparable to 17–19 NT. Soft food intake was not influenced by denture wearing. In a ranking of oral conditions, those with more than 24 NT had the highest test values for all tests, and those with complete sets of dentures the lowest except for the number of strokes to the first swallow of an almond. Conclusion: Removable denture wearing can be regarded as a handicap when measured with objective masticatory tests using chewing gum and the intake of hard foods. The number of chewing strokes to the first swallow of an almond and the intake of soft foods is not affected by the wearing of removable dentures.     

Possible variation of the human oral bacterial community after wearing removable partial dentures by DGGE

Although it is well-known that variations of the microbial community in a specific location of human body may be associated with some diseases, the developing change of the oral microbiota related to oral diseases before and after wearing the removable partial dentures (RPD) is not completely understood. In this study, three kinds of samples (saliva, supra- and subgingival plaque, and oral mucosal surfaces) were collected from the 10-patients group at three different times: before, 1-month and 6-months after the treatment. Ten healthy adults were also selected as the control group. Denaturing gradient gel electrophoresis was applied to identify the bacterial profiles and to analyze the dynamics of the oral microbial population in the pre- and post-therapy. The ANOVA of Repeated Measurement Data indicated that, in the saliva and mucosal surfaces, wearing RPDs caused significant change of numbers of amplicons. As many as 607 amplicons were chosen to cut out and re-amplify by PCR. After cloning and sequencing, a total of 16 bacterial genera were identified. The health-associated genera such as Streptococcus, Neisseria, Rothia, Corynebacterium, Leptotrichia, Gemella, Veillonella, Selenomona and Actinomyces tended to decrease, whereas the disease-associated species including Streptococcus mutans tended to increase. In general, wearing RPDs influenced the diversity of the bacterial species in the oral microbial ecosystem. It is noteworthy that the oral environment will be changed from the healthy status towards the disease status after the treatment.