Evaluation of key parameters in a potentiostatic corrosion test for dental amalgam

OBJECTIVES: Participation in a Round Robin study of potentiostatic corrosion test guidelines for dental amalgam was undertaken for the purpose of developing an accurate set of draft guidelines. METHODS: Dispersalloy, sybraloy, aristalloy, phasealloy, and tytin were used as the amalgam specimens. They were prepared following the guidelines, then coupled to a copper wire, cemented into glass tubes, and polished to a 600-grit finish. A corrosion cell was prepared using a carbon counter-electrode, a standard calomel electrode (SCE) as the reference electrode, and amalgam as the working electrode. A 37 degrees C solution of 10 g/l NaCl with a minimum volume of 300 ml was used. Within 5 min of polishing, the open circuit potential (OCP) was recorded for 10 min. Next, the specimen was polarized to 0 mV versus SCE, and the currents were recorded for a 24-h time period. Corrosion results were analyzed statistically with one-way ANOVA (p < 0.05) and the multiple comparisons Student-Newman-Keuls post-hoc test. RESULTS: Problems that occurred with evaporation, beaker size, carbon electrode length, SCE cap removal, glass tube fracture, polishing technique, and fresh electrolyte are easily avoidable with further explanation or reminder notes. Observations made concerning starting time, initial OCP recording, millivoltage, and solution temperature were determined to be necessary for the accuracy of test results. Analysis of results should include clarification of units, and graph interpretations. Finally, the number of specimens per amalgam should be increased from one to three so that statistical analysis can be performed. Using three specimens per amalgam, the method revealed corrosion susceptibility as measured by the improved test: aristalloy > sybraloy > (dispersalloy, phasealloy, tytin). SIGNIFICANCE: Having run the initially proposed guidelines, a number of clarifying changes were made so that the corrosion susceptibilities of five dental amalgams could be clearly differentiated.     

五种龋病风险评估方法对口腔门诊患者患龋风险水平区分能力的研究

目的本研究旨在建立一种适合我国门诊病人龋风险评估体系-龋风险窗口(caries risk window,CRW)预测法,并与现有国外龋风险评估系统进行比较,评价其对门诊患者患龋风险等级区分能力和检测结果的一致性。方法选取111名门诊患者,进行临床检查和问卷调查。口腔检查包括患龋状况、口腔卫生状况、牙齿发育缺陷等;问卷调查包括饮食习惯、口腔卫生行为和就医行为。分别用五种龋风险评估方法确定个体的患龋风险等级:CRW预测法、Cariostat法、ADA龋风险评估、CAMBRA(Caries Management by Risk Assessment)、Cariogram系统。采用卡方检验比较五种方法对患者患龋风险水平的区分度;采用加权kappa比较五种方法检测结果的一致性。结果五种方法判断出龋高风险个体的比例从高到低分别是:CAMBRA(93%)、ADA(86%)、Cariogram(77%)、CRW(65%)和Cariostat(56%)。ADA和CAMBRA的一致性最高(加权kappa:0.593,P<0.05),属于中等水平。Cariogram与CAMBRA和ADA,CRW与ADA和Cariogram的一致性属于一般水平(加权kappa:0.221~0.358,P<0.05)。CRW与CAMBRA和Cariostat的一致性属于较差水平(加权kappa:0.150~0.161,P<0.05)。其它方法之间的一致性没有统计学意义。结论CRW和Cariogram对门诊患者患龋风险等级的区分能力优于CAMBRA和ADA龋风险评估方法,Cariostat居中,不同龋风险评估体系结果的一致性不高。需通过纵向研究进一步评价龋风险评估体系的准确性。     

Effect of Regulatory and Professional Guidelines on the Development and Marketing of a Dental Device: Case History

The FDA encourages organizations such as the ADA to develop voluntary standards for drugs and dental devices. The landmark process of gaining ADA approval of an oral irrigator as the first therapeutic device is described. The process was time consuming and expensive, and obligates the manufacturer to submit all future marketing and advertising claims for ADA review. The ADA should continue to ensure standardized guidelines for all product categories. Education of the dental profession and the consumer concerning the significance of the ADA seal of approval is encouraged.     

FDA and ADA Evaluation of Dental Implants

The FDA classification of endosseous dental implants (EDI) is reviewed. Factors impacting the long-term efficacy of dental implants and the guidelines for development of EDI are enumerated. The role of the ADA in evaluation of EDIs is also discussed. Recommendations for development of performance criteria and reporting format are made.     

Dentists'' Uncertainties about Materials and Devices: an Introduction to the Problem

Questions concerning evaluation of dental materials and devices by the FDA and ADA are raised. Examples of several products are discussed.     

What Do Consumers Want?

A consumers' advocate discusses the needs of the consumer in evaluating dental products. Although commending the roles of the FDA and ADA in evaluating products, numerous questions are raised and recommendations made concerning advertising claims.     

Ethical Perspectives on the FDA and ADA Evaluation of Dental Products

Contemporary bioethics is concerned with qualitative decisions rather than quantitative decisions. Several examples are discussed including the role of patients as decision makers in their treatment and in their assignment within clinical trial groups.     

Professionally Applied and Prescribed Fluoride Products

The US regulatory process relative to the marketing of sodium fluoride dietary supplements and professionally applied topical fluorides is examined with regard to interactions of ADA, NIH, academia, and the FDA, as well as resultant effects on industry, practitioners, and patients. Restrictions on noncaries use of fluoride limit commercial claims, but not professional practice. Prenatal fluoride supplements are still unapproved. Finally, the effects of generic competition and the regulatory process on costs, sales, quality of professional fluoride products and on new product research are discussed.     

An estimation of the strength of attachment of subgingival calculus to extracted teeth

Abstract The approximate shear bond strength of subgingival calculus was measured on freshly extracted teeth. The experimental method was validated on polycarboxylate controls. The object was to specify a suitable upper limit for periodontal dressing adhesion, and a level of 4.0MN/m² is suggested by these results     

4.3 Towards a global superstore of quality-assured modularized learning programmes

Our section's assignment entails exploration of the current challenges to develop criteria for quality assurance of dental e-learning material. Our work has involved comparison of current methods of assessment, the identification of best practice and the formulation of guidelines and criteria for producers and assessors. We anticipate the need for a standing international body responsible for the revision and refinement of guidelines and criteria and that might award a 'Seal of Approval'.     

Restructuring an undergraduate dental curriculum to global standards – a case study in an Indian dental school

Globalisation has affected all aspects of life and dentistry is no exception. In the context of today's dentist being a global citizen, undergraduate training in dentistry is set to ensure converging standards so that international recognition of dental qualifications can move forward. The decision of the Dental Council of India to expand the undergraduate dental program to five years provides an opportunity to be part of the endeavor of the Global Dental Congress to achieve converging standards which was initially for the European Union, and now spreading out globally. Economic emergence in Indian subcontinent has resulted in growing oral health care needs both in quality and quantity. To address this issue, the graduating dentist needs to be trained following a competency based curricular model. Access to Internet facilitated the goal of achieving converging standards of dental schools to be feasible because of the instant communication and capacity to share information about training strategies via technology across the globe. Upgrading the undergraduate training to global standards by dental schools in India could be a wise and strategic move both for attracting students to study in India, as well as retaining the graduates after their training. The following is a case study of an Indian dental school set to restructure the undergraduate curriculum to global standards using the 8 steps of Kotter's transformational change. Change in curriculum and the subsequent accreditation of the school in global platform not only attracts prospective students but also results in producing competent dentists. Dental education provided by the institution can result in quality assurance, benchmarking the assessment system to achieve international recognition. This paper highlights the need and importance of facilitation of international convergence with long term aspirations for mutual recognition of international degrees.     

老年人龋病的防治重点——论老年人口腔健康标准之无龋洞

口腔健康是全身健康的重要组成部分,关注老年人口腔健康,对于维护老年人全身健康,提高其生活质量具有重要意义。那么什么情况下可以定义为老年人口腔健康呢?此前关于老年口腔健康,国内外尚未见全面的标准提出。刘洪臣于2019年结合世界卫生组织的口腔健康标准提出老年人口腔健康的10项指标,即1.牙齿清洁;2.无龋洞;3.无疼痛感;4.牙齿和牙龈颜色正常;5.无出血现象;6.牙齿排列整齐;7.不塞牙;8.无缺牙;9.咬合舒适;10.无口臭引起人们的广泛关注。本文将主要围绕十项标准中的无龋洞来讨论龋病对老年人健康的危害(面部及全身的影响)、老年人龋病的防治的重点以及探讨无龋洞的理念作为老年口腔健康标准的意义。     

现行拔牙钳的国际、国内标准对比解析

拔牙钳使用历史悠久、生产工艺成熟、临床应用普遍，是一种最基础的牙科手术用器械。为保证拔牙钳的安全、降低其伤害风险，全球很多国家都出台了拔牙钳的产品标准，国际标准化组织ISO也制定了拔牙钳的国际通用标准。该文将我国现行拔牙钳标准与国际通用标准进行逐条比较，结合拔牙钳的发展趋势进行分析，旨在为广大企业、监管部门、技术支撑机构和科研院所提供一份标准使用指南。     

Properties of athletic mouth protectors and materials

The properties of a variety of mouth protectors and sheet materials used to fabricate custom mouth protectors were determined in order to recommend limits for a specification. Hardness, water sorption, water solubility, impact absorption, and tear strength were measured, and limits for these properties were suggested.