中华口腔医学会第五次全国牙体牙髓病学术会议纪要

中华口腔医学会第五次全国牙体牙髓病学术会议纪要中华口腔医学会第五次全国牙体牙髓病学术会议于１９９７年１０月１６～１８日在四川成都召开，此次会议由华西医科大学口腔医学院承办。大会共收到全国各地论文３９５篇，其中牙体硬组织非龋性疾病７５篇，龋病９２篇，牙...     

龋病病变中的生物电现象初探

采用专门研制的牙齿膜电位测试仪对患者同一牙的龋变表面和正常表面进行测量，发现大多数龋变表面的生物电位低于正常表面，相对为负电位，而正常表面为正电位。用现代电化学理论分析这一现象，作者认为在龋病发生发展过程中，口腔内存在着原电池作用。在唾液作为电解液的作用，表面和正常表面成为原电池的两极，不断产生腐蚀电流，破坏牙体硬组织并刺激牙髓。作者将这种理论假设为“龋病发病机理的生物电化学理论”。     

复合树脂直接粘接修复技术的临床观察

粘接技术在口腔医学的各个领域中都起着很重要的作用。与传统的直接和间接修复技术相比 ,复合树脂直接粘接修复技术有其优点。本文将就其作一综述。　　龋病是牙体硬组织的慢性进行性损伤。随着口腔保健条件及口腔卫生环境的改善 ,龋病的发病率有很大程度的降低。尽管如此 ,由于其他原因造成的牙体硬组织损伤却呈上升趋势[1,2 ] 。牙体组织的非龋性缺损可能是由于磨损、磨耗、腐蚀及外伤等原因造成[3 ] 。其中磨耗是一个物理过程。牙齿在口腔环境中暴露越久 ,受到的磨耗性伤害越大[4 ] 。磨耗与龋病不同的是它引起的损害可能影响到几乎所有…     

含氟粘接剂的口腔临床研究进展

粘接剂被广泛应用于口腔临床治疗,在修复牙体组织缺损,维持正常的牙齿形态和功能方面发挥重要的作用.目前口腔领域常用的非含氟粘接剂缺乏有效的抗龋性能,易产生继发龋,失败率高,远期效果差.而氟化物与粘接剂的混合制作能够在不影响材料良好的生物力学性能的基础上,赋予粘接剂一定的抗菌性能和促牙体硬组织再矿化性能,在口腔修复和龋病防...     

龋损、龋蚀、龋坏、龋变、龋患

牙齿因龋病而致牙体硬组织损坏 ,外文称为carieslesion ,中文译名有龋损、龋蚀、龋坏、龋变、龋患。据英汉医学词汇 ,lesion译为损害 ,因此建议carieslesion译为龋损 ,其他龋蚀、龋坏、龋变、龋患均废弃不用 ,以免混淆龋损、龋蚀、龋坏、龋变、龋患@史俊南$第四军医大学口腔医学院!陕西西安710032     

Er.Cr.YSGG激光在龋病治疗中的应用研究

Er．Cr．YSGG激光是新一代水动力生物激光系统,在龋病治疗中的应用正不断深入。本文对其去除龋坏牙体组织的能力、原理,清除玷污层和蚀刻牙体硬组织能力及应用的安全性进行综述。     

聚类分析法在龋病流行病学研究中的应用进展

<正>龋病是一种牙体硬组织慢性疾病，严重威胁人类的健康^[1]。第四次全国口腔流行病学调查结果显示，12岁儿童中有34.5%的人患龋病，而在35～44岁的人群中患龋率则高达89.0%^[2]。龋病可造成牙体缺损、牙髓病和根尖周病等，影响牙的功能与美观，可使患者的咀嚼功能减退、发音功能障碍，甚至可能会导致颞下颌关节紊乱和错牙合畸形。目前公认龋病是在一定的时间内，受宿主易感性、口腔细菌和饮食等因素影响的一种口腔牙体疾病^[3]。这些影响因素具体为宿主的基因、唾液^[4]、细菌的种类^[5]及其附着方式、饮食的种类及频率等。而在宏观上，龋病的发生则可能受到家庭、政策、社会和经济^[6]等因素的影响。     

患龋时牙菌斑和唾液中的矿物质

牙体硬组织的生理状况、牙菌斑和唾液中的矿物质成份都与龋病的发生有着密切的关系。为了研究患龋时牙菌斑和唾液中矿物质结构变化,作者选择了在一年中处于同一劳动环境、日常生活和营养状况的18岁～20岁健康男性青年20名,其中10名牙列完整、无龋齿,另10名牙列完整,分别患有1～5个初期龋(无龋齿合并症,亦未作充填治疗)。在获取标本前5天被检者停止口腔清洁护理,于第6天清晨空腹时采集标本。用特制的菌斑采集工具取样,     

口腔医学基础——口腔内科学

龋病及牙体硬组织非龋性疾病20080567后牙复合树脂修复各类洞形4年临床疗效评估／叶楠…∥牙体牙髓牙周病学杂志．-007，17（5）．-286～288     

Er：YAG激光在龋病防治中的研究进展

龋病是影响人类口腔和全身健康的常见疾病,目前龋病的预防和治疗方法主要是应用氟化物及窝沟封闭和涡轮机机械去腐。铒钇铝石榴石(Er：YAG)激光是一种新型牙体硬组织激光,可以高效切割牙体硬组织,因其安全、无痛、微创而越来越受人们重视。本文就其在龋病预防和去腐备洞对牙髓的影响、微渗漏、粘接性等方面性能的研究进展作一综述。     

Zinc in the mouth, its interactions with dental enamel and possible effects on caries; a review of the literature

Zinc is an essential trace element. In the mouth, it is present naturally in plaque, saliva and enamel. Zinc is formulated into oral health products to control plaque, reduce malodour and inhibit calculus formation. It has good oral substantivity, and elevated concentrations can persist for many hours in plaque and saliva following delivery from mouthrinses and toothpastes. Although low concentrations of zinc can both reduce enamel demineralisation and modify remineralisation, during caries clinical trials, the addition of zinc to fluoride toothpastes has not affected their ability to reduce caries. Mechanistic studies may help explain this apparent contradiction. Zinc is readily desorbed from hydroxyapatite by calcium, which is plentiful in plaque and saliva. Where crystal-growth sites remain occupied by zinc despite this, they may simply be 'over-grown' by remineralisation initiated at unoccupied sites. Further, under certain conditions, low concentrations of zinc can enhance remineralisation of enamel lesions, by retarding lesion arrestment. Although this may help to explain the apparent lack of an overall zinc effect on caries, it seems unlikely that any negative effects would be countered exactly by positive effects. Further mechanistic studies, complementing well-designed in vitro and in situ caries studies, should lead to further understanding of the zinc-enamel interactions relevant to demineralisation and remineralisation.     

Role of fluoride in oral health promotion

Fluoride has played a pivotal role in oral health promotion over the past 50 years. This paper reviews key issues currently impacting on the role of fluoride in preventing dental caries. The understanding of the process of dental caries and the mode of action of fluoride has changed in recent years. Dental caries is a continuous process of demineralisation and remineralization of the enamel and fluoride plays a key role in this process through its action at the plaque enamel interface. It is now accepted that the primary mode of action of fluoride is post-eruptive. The post-eruptive action of fluoride has resulted in new methods of delivering fluoride. The paper discusses the impact of these new methods of delivering fluoride on total fluoride intake in children and on the prevalence of dental fluorosis. The role of different methods of delivering fluoride both on a community and individual basis is presented and recommendations are outlined.     

Biology of Streptococcus mutans-derived glucosyltransferases: role in extracellular matrix formation of cariogenic biofilms

The importance of Streptococcus mutans in the etiology and pathogenesis of dental caries is certainly controversial, in part because excessive attention is paid to the numbers of S. mutans and acid production while the matrix within dental plaque has been neglected. S. mutans does not always dominate within plaque; many organisms are equally acidogenic and aciduric. It is also recognized that glucosyltransferases from S. mutans (Gtfs) play critical roles in the development of virulent dental plaque. Gtfs adsorb to enamel synthesizing glucans in situ, providing sites for avid colonization by microorganisms and an insoluble matrix for plaque. Gtfs also adsorb to surfaces of other oral microorganisms converting them to glucan producers. S. mutans expresses 3 genetically distinct Gtfs; each appears to play a different but overlapping role in the formation of virulent plaque. GtfC is adsorbed to enamel within pellicle whereas GtfB binds avidly to bacteria promoting tight cell clustering, and enhancing cohesion of plaque. GtfD forms a soluble, readily metabolizable polysaccharide and acts as a primer for GtfB. The behavior of soluble Gtfs does not mirror that observed with surface-adsorbed enzymes. Furthermore, the structure of polysaccharide matrix changes over time as a result of the action of mutanases and dextranases within plaque. Gtfs at distinct loci offer chemotherapeutic targets to prevent caries. Nevertheless, agents that inhibit Gtfs in solution frequently have a reduced or no effect on adsorbed enzymes. Clearly, conformational changes and reactions of Gtfs on surfaces are complex and modulate the pathogenesis of dental caries in situ, deserving further investigation.     

The relationship between dental caries status and dental plaque urease activity

INTRODUCTION: Ammonia production from the metabolism of urea by urease enzymes of oral bacteria moderates plaque acidification and may inhibit dental caries, as suggested by in vitro studies and indirect clinical observations. The objective of this study was to examine the relationship of urease activity with dental caries at the clinical level. METHODS: Urease activity was measured in dental plaque and saliva samples from 25 caries-free subjects (CF) and in eight subjects with six or more open caries lesions (CA). Plaque and saliva collection was repeated for each subject 1 week later using identical procedures. RESULTS: Urease-specific activity in the dental plaque of CF subjects was significantly higher compared to that in the subjects with caries. The association of low plaque urease levels with increased caries was further supported by odds ratio analysis using different plaque urease cut-off points. Using a receiver operating characteristic curve it was estimated that there was an approximately 85% probability of correctly classifying the subjects as CA or CF based on the relative ordering of their plaque urease activity levels. No statistically significant differences were observed in salivary urease activity. CONCLUSION: This study suggests that loss of alkali-generating potential of tooth biofilms via the urease pathway has a positive relationship to dental caries.     

微生态制剂及抗菌肽在龋病防治中的研究进展

龋病是以细菌因素为主的多种因素引起的口腔微生态失衡为特征的口腔慢性感染性疾病,是人类最常见的细菌性疾病^[1,2]。目前龋病预防的关注点集中于对牙菌斑的去除,而牙菌斑实则为大量共生微生物集中组成,因此"移除或杀灭所有"菌斑微生物的理念对于致病微生物创造了一个开放的非竞争性的环境。传统的方法预防或治疗龋病,无法从根本上解决牙体组织损伤及细菌耐药性等问题。微生态制剂及抗菌肽应运而生,通过抑制口腔病原菌毒性作用以达到调节口腔微生态平衡的目的,是预防及治疗龋病的新方法。     

Oral hygiene as a risk indicator of enamel and dentin caries

Dental researchers have postulated that the risk factors for enamel and dentin caries may not be the same. A review of the literature ascertained that data to support this theory are lacking. Objectives: To evaluate the risk indicators of enamel and dentin caries of the permanent dentition in a study group who had limited access to fluorides and made limited use of dental services. Methods: The study was conducted in Goa, India. Data came from a cross-sectional survey of 1189 seventh grade children, which consisted of a clinical dental examination and a self-administered questionnaire to their parents. The cavitated and non-cavitated criteria were used to score for caries, and the Silness-Loe index for plaque. Results: The mean age of the children was 12.2 years. The percentage of children caries free in the permanent dentition was 22.2%, the mean± s for dmfs, enamel and dentin lesions were 4.20±5.10, 2.59±2.89 and 1.61±3.30 respectively, and the mean plaque score was 1.00±0.48. Results of regression analyses showed that the risk indicators of prevalence and severity of caries differed depending on lesion type. The only variable that was consistently a risk indicator of presence and severity of both dentin and enamel caries was poor oral hygiene. Mother's highest level of education and presence of fluorosis were also risk indicators of enamel and dentin caries. The presence of decayed primary teeth was a risk indicator of enamel caries; and fluorosis severity, use of fluoride toothpaste at the time of the survey, and toothbrushing frequency were risk indicators of dentin caries. The observed caries-oral hygiene association seen is explored further.     

The role of sucrose in cariogenic dental biofilm formation--new insight

Dental caries is a biofilm-dependent oral disease, and fermentable dietary carbohydrates are the key environmental factors involved in its initiation and development. However, among the carbohydrates, sucrose is considered the most cariogenic, because, in addition to being fermented by oral bacteria, it is a substrate for the synthesis of extracellular (EPS) and intracellular (IPS) polysaccharides. Therefore, while the low pH environment triggers the shift of the resident plaque microflora to a more cariogenic one, EPS promote changes in the composition of the biofilms' matrix. Furthermore, it has recently been shown that the biofilm formed in the presence of sucrose presents low concentrations of Ca, P(i), and F, which are critical ions involved in de- and remineralization of enamel and dentin in the oral environment. Thus, the aim of this review is to explore the broad role of sucrose in the cariogenicity of biofilms, and to present a new insight into its influence on the pathogenesis of dental caries.     

An investigation of the oral status and reported oral care of children with heart and heart-lung transplants

Aim . To investigate the oral health status and oral microflora of children who have received heart and heart-lung transplants. Parental knowledge and current practice of oral health procedures by the child were also investigated.
Sample and method . Thirty-five children attending the Cardio-Thoracic Transplant Unit, Great Ormond Street Hospital for Children were included. Measurements were compared with children matched by age and gender attending the trauma clinic at the Department of Paediatric Dentistry, Eastman Dental Hospital. Teeth were examined for the presence or absence of caries or enamel defects. Plaque deposition, gingivitis, gingival bleeding and gingival enlargement were measured and a swab was taken to look at the oral microbial flora. A questionnaire was used to assess parental knowledge of dental health procedures and the current practice of these.
Results . There were no significant differences between transplant and control children in caries experience, plaque or gingivitis. Children with heart or heart-lung transplants had significantly greater numbers of enamel defects and more gingival enlargement than control children, children in the heart transplant group had significantly more gingival bleeding. There was little difference in the dental knowledge and reported behaviour of the transplant group compared to the control group.
Conclusion . The dental needs of heart and heart-lung transplant patients treated at the Great Ormond Street Hospital for Children were similar to those of the control group in this study, however further improvement could be made in educating parents and children on the importance of caries prevention and good oral hygiene.     

菌斑微生物群落构成变化与儿童龋病相关研究进展

龋病作为多因素影响的疾病,细菌是龋病发生的始动因素,生态菌斑学说的提出以及现代分子生物学手段的应用,使得学者们能够从微生物角度对菌斑生物膜中细菌的种群分布、菌群多样性、菌斑微生物群落变化与儿童龋病之间的联系进行了更深入的探讨.菌群多样性的降低与龋病发生密切相关,早于龋病发生前的6个月就可以检测到菌群多样性水平的降低,这...     

An assessment of recent advances in the study of the chemistry and biochemistry of dental plaque fluid

This paper discusses key points made during the symposium in the light of work carried out in other laboratories. It is emphasized that the unique importance of plaque fluid is that the net result of chemical changes induced by microbial activity is reflected in this medium, which is in intimate contact with the enamel surface, and that this medium is accessible to chemical and biochemical analyses. However, in order to assess the cariogenic potential of plaque, we must consider the properties of both whole plaque and plaque fluid together. Although it is apparent that results of plaque fluid composition are sensitive to both isolation and the storage procedures utilized, plaque fluid appears to be a distinct entity within the oral cavity. Technical advances have been made which allow for the determination of the activity of selected ions (hydrogen, calcium, phosphate, potassium, fluoride) in plaque fluid obtained from a single site within the mouth. It appears, however, that such data alone may be insufficient to define the cariogenic potential of plaque appropriately. Evidence is presented from which it can be concluded that, with use of pooled samples of plaque obtained from individuals with clear differences in caries experience, results on plaque and plaque fluid composition can be obtained which are consistent with noted differences in caries susceptibility. The importance of base production is also discussed, and it is noted that few studies have been carried out to elucidate the role of proteins found in plaque fluid. In conclusion, recent advances in the study of plaque fluid have provided new insights into the mechanism of caries formation which are also germane to the formation of dental calculi.