Answers from dentists, dental hygienists and dental assistants to questions asked by patients concerning preventive dental matters

142 dentists, 21 dental hygienists and 35 dental assistants were asked lo fill in a questionnaire which consisted of 40 questions about preventive dental matters regularly asked by Dutch dental patients. The 40 questions were submitted to experts in the field of preventive dentistry. The experts were in agreement on 26 questions. It was decided to use these questions for analysis. The average percentage of correctly answered questions was: for the dentists 53%, for the dental hygienists 58% and for the dental assistants 37%. The group of 142 dentists was further analyzed. It appears that the knowledge about preventive dental matters increases subsequently with each year of gradual ion. Analysis of the dentists who graduated from Dutch dental schools in their capacity as private practitioner, as faculty member or in the school dental service, revealed that there was no difference in knowledge between these groups. With some reservations the conclusion can be stated that an obvious necessity exists for post-academic courses in preventive dentistry in the groups concerned. Greater uniformity is needed between the views of the experts and the dental professionals who treat patients daily.     

Shifts between use and non-use of dental services among young Danish adults over a 3-year period

Utilization of dental services among three groups of young adults was studied longitudinally. Each year from age 16 to age 19, participants were defined as users or non-users of alternative dental programs. Dental programs were taking place with public dental health service clinics (n = 386), with private dental practitioners, free of charge (n = 161), and with private dental practitioners, partially reimbursed by health insurance (n = 261). The paper analyzes whether the pattern of utilization of the last two groups might be described by a Markovian model defining use or non-use of dental care each of 3 years as two mutually exclusive Markovian states. Contingency table analysis of the relationships of the utilization status and sex, social group, and delivery program showed that the utilization pattern could not be described by a Markovian model. Conversely, strong relationships between 1-yr user status and 3-yr user status was found. Implications in relation to the prevailing dental health care policy emphasizing regular dental care and continuity between child dental health care and young adult dental programs are discussed.     

等离子体处理对口腔修复材料粘接性能的影响

口腔材料与材料之间、修复体与牙体组织之间良好的粘接是临床修复成功的保证.等离子体是气体在高能量作用下部分或完全电离产生的气体云,具有高效率、低能耗、安全和无二次污染等优点.等离子体可改变聚合物的表面结构并形成一个惰性的表面保护层,高材料的润湿性、生物相容性和耐用性.等离子体表面处理可提高丙烯酸树脂基托、纤维增强复合材料、玻璃陶瓷、多晶陶瓷和复合树脂等与各种基质之间的粘接力.本文就目前国内外等离子体及其在口腔材料粘接性方面的研究进展作一综述,旨在为等离子体广泛地应用于口腔临床提供理论依据.     

High-frequency hearing of dental personnel Occupational Hazards

234 dentists and dental nurses were examined with a normal and a high-frequency audiometer in high standard clinical conditions. Their ordinary and high-frequency hearing as compared with the controls showed no significant differences. Thus, exposure to high-frequency noise from high-speed drills and other modern dental instrumentation does not appear to be harmful to one's hearing and does not necessitate audiologic screening procedures for dental personnel.     

The effect of dental restorative materials on dental biofilm

To investigate the arrangement of biofilms formed in vivo, volunteers wore splints with slabs of six different dental materials inserted to collect smooth surface plaque. After 5 d of undisturbed plaque accumulation, the specimens were vital stained and analyzed by the confocal laser scanning microscopy (CLSM) to evaluate the percentage of vital biofilm microflora (VF percentage). Further parameters were the area of the specimens covered by plaque (surface coating; SC, %) and the height of the biofilms (BH, pm). The metals amalgam and gold, the compomer, as well as the glass-ionomer cement harboured an almost entirely dead biofilm (VF <8%). Resin composite led to vitality values between 4 and 21%, while a very thin biofilm on ceramic revealed the highest vitality values (34-86%). SC varied from 6% on glass-ionomer cement to 100% on amalgam. BH reached its highest value on amalgam and gold of 17 and 11 microm, respectively, while heights of between 1 and 6 microm were found on the ceramic, resin composite, compomer and the glass-ionomer cement. Within their limits, the present findings indicate that amalgam, gold, compomer and glass-ionomer cement exert an influence against the adhering biofilm. No general relationship could be established between the different parameters VF percentage, SC percentage and BH (microm).     

A comparison of dental restoration outcomes after placement by restorative function auxiliaries versus dentists

Objectives: To compare the outcomes of restorations placed by restorative function auxiliaries (RFAs) with those placed by dentists. Methods: Between July 1, 2007, and June 30, 2008, we matched 455 restorations placed by RFAs working at HealthPartners Dental Group with the same number placed by dentists. Restorations were matched by tooth number, American Dental Association procedure code, and patient age‐group. Results: Of 910 restorations, 17 (1.9 percent) had problems potentially related to the filling or crown placement during the first year. Problem rates were not significantly different (p = 0.33) for restorations placed by RFAs (1.3 percent, 6 of 455) and those placed by dentists (2.4 percent, 11 of 455). Conclusions: There was no significant difference in problem rates for restorations placed by RFAs versus those placed by dentists. This finding may free dentists to handle more difficult cases, alleviating some of the pressures of daily practice and meeting the need for improved access.     

Role of health education among services rendered by dental personnel in Finland

The quantity and origins of dental health education information were surveyed in June 1973 by interviews with a sample comprising 505 persons drawn to cover the total Finnish population aged 15 years and over. The interview revealed that tooth extraction was the most frequent (43%) of the measures performed during the last visit to dentist and tooth filling was the measure second in frequency (41%). Rare measures were periodontal treatment (13%) and teaching of home care (2%). Radio and television were the most frequently mentioned sources of information (47%); however, the evaluations of the reliability of information on dental health education in the mass media were skeptical. Dental service personnel was a not minor source of information (33%) and its effectiveness was recognized. Although dental health education performed on the personal level is a great challenge, which should be accepted by the whole dental personnel, a total of 58% of the interviewees were of the opinion that they had not received sufficient information on dental home care.     

An experimental study of the adhesion of bacterial layers to some restorative dental materials

Abstract — In the present study a powerful method for measuring adhesion is introduced. It is, based on the observation that the bacterial layer is usually capable of maintaining an interior pressure, but fractures when this pressure exceeds a certain critical value characteristic of the mechanical and adhesive properties of each specific bacteria and its formed matrix. A water jet: from a nozzle was directed on the bacterial layer of the specimen. A specimen covered with a layer of Streptococcus mutans, grown in an artificial mouth, was placed on a sledge and displaced twice, at constant speed in front of the jet, thus forming two grooves in the plaque layer. When the grooves are made in parallel utilizing different water pressures, the critical pressure for causing disengagement of the plaque, p_c, can be evaluated. It is claimed that p_c gives an estimate of the plaque adhesion. Polished and ground surfaces of four materials were investigated, namely amalgam, PMMA, gold and porcelain-coated gold.     

Changes in health over time in patients with symptoms allegedly caused by their dental restorative materials

Abstract – Objectives: In Sweden, many patients with symptoms allegedly caused by their dental materials have exchanged their restorations, but the effects of the exchange have been insufficiently investigated. Therefore, the aim of the study was to describe the change in health over time for these patients and the hypothesis was that the patients could be divided based on their symptoms and that the ability to recover differs between these groups. Furthermore, we also examined if other factors such as replacement of dental restorative materials and follow‐up time had any impact on the perceived health status. Methods: A questionnaire was sent to 614 patients who had been referred to the School of Dentistry, Umeå, Sweden, with symptoms allegedly caused by dental restorative materials. The response rate was 55%. Results: The risk of having any further complaints was higher for patients with complex symptoms (P = 0.03) and these patients had exchanged their restorations to a significantly larger extent than the others (P = 0.03). The remaining complaints was more frequent among men (P = 0.02). Exchange of dental restorative materials had no significant impact on the ability to recover completely. However, the patients who had exchanged their restorations completely perceived a significantly larger alleviation of their symptoms than the others (P < 0.01), although the frequency of most of the symptoms had increased. Conclusions: Patients with complex symptoms had a more unfavorable long‐term prognosis concerning persistent complaints than those with localized symptoms only. Furthermore, the results indicate that the patients might experience health improvements after removal of their dental restorative materials. The reason for this improvement, however, is unclear. Further analyses regarding other possible explanations than the ‘odontological/medical’ are needed.     

Variation in radiographic interpretation and restorative treatment decisions on approximal caries among dentists in Norway

Of a random sample of dentists in Norway (n = 741), 83% responded to a questionnaire about their use of radiographs in and their opinions and knowledge about the diagnosis of approximal caries. There was great disparity in criteria for initiation of restorative treatment of approximal caries based on radiographic appearance. Two thirds of the dentists would do restorative treatment of lesions confined to enamel, the others would wait until lesions had reached the dentin before treatment was commenced. The criteria for restoration based on radiographic appearance was best correlated with the dentists' opinions about cavity formation. About 20% of the variation in criteria among dentists was explained by the radiographic appearance dentists associated wih the presence of a cavity. The majority of the dentists believed that approximal caries progressed faster than is indicated by progression studies. The interval between recall examinations using radiographs was not consistently shorter for dentists who decided to carry out operative caries treatment at a relatively advanced stage.     

Fluoride uptake from restorative dental materials by human enamel

abstract – The purpose of the study was to determine the uptake in vitro of fluoride from restorative materials by tooth ename1 and whether prior etching of the ename1 causes a change of uptake. The outermost layer of the labial surface of extracted canines was removed by grinding and the enamel was covered with five different fluoride-containing materials; a silicate, a composite resin, an amalgam, a silicophosphate, and a polycarboxylate luting cement. The material was either removed immediately or after storing the tooth in distilled water. The fluoride content was determined using a sensitive physical method based on the ¹⁹F (p, αy) ¹⁶O reaction. In addition, the fluoride content of enamel after etching for different periods of time and of etched enamel which had been in contact with silicate cement was determined. The mean fluoride content of uncovered interior ename1 was 226 parts/10⁶. All materials, except the composite, increased clearly the fluoride content of the underlying enamel. Etching of interior enamel also increased the fluoride values. No difference could be shown in fluoride uptake from silicate and composite resin between etched and unetched enamel.     

Thiol-ene-methacrylate composites as dental restorative materials

Objectives

The objective of this study was to evaluate composite methacrylate-thiol-ene formulations with varying thiol:ene stoichiometry relative to composite dimethacrylate control formulations. It was hypothesized that the methacrylate-thiol-ene systems would exhibit superior properties relative to the dimethacrylate control resins and that excess thiol relative to ene would further enhance shrinkage and conversion associated properties.

Methods

Polymerization kinetics and functional group conversions were determined by Fourier transform infrared spectroscopy (FTIR). Volume shrinkage was measured with a linometer and shrinkage stress was measured with a tensometer. Flexural modulus and strength, depth of cure, water sorption and solubility tests were all performed according to ISO 4049.

Results

All of the methacrylate-thiol-ene systems exhibited improvements in methacrylate conversion, flexural strength, shrinkage stress, depth of cure, and water solubility, while maintaining equivalent flexural modulus and water sorption relative to the dimethacrylate control systems. Increasing the thiol to ene stoichiometry resulted in further increased methacrylate functional group conversion and decreased volume shrinkage. Flexural modulus and strength, shrinkage stress, depth of cure, water sorption and solubility did not exhibit statistically significant changes with excess thiol.

Significance

Due to their improved overall functional group conversion and reduced water sorption, the methacrylate-thiol-ene formulations are expected to exhibit improved biocompatibility relative to the dimethacrylate control systems. Improvements in flexural strength and reduced shrinkage stress may be expected to result in composite restorations with superior longevity and performance.     

Urinary mercury levels and early changes in kidney function in dentists and dental assistants

Mercury exposure and renal function parameters were examined in 68 dentists and 64 dental assistants. The levels of mercury in urine were low: only three individuals exceeded 20 micrograms/l. Increased excretion of urinary proteins and increased activity of urinary enzymes were observed. This enhanced prevalence of renal function changes appeared not to be related to the mercury urine level, age, sex, or smoking and drinking habits. Only for men was a positive relation between the level of mercury in urine and the activity of beta-galactosidase found. The proteinuria may be due to one or more potential nephrotoxic agents used in dental practice.     

应用牙本质屏障法测定牙齿充填材料体外细胞毒性

目的:探讨牙本质屏障法用于牙齿充填材料体外细胞毒性试验测定的特点。方法:低速锯片切新鲜拔除的磨牙,获取紧邻牙髓的颊侧牙本质片,选择通透值相近的牙本质片作为牙本质屏障,制作细胞毒性体外测试装置,用此装置测定氧化锌丁香油水门汀、复合树脂、玻璃离子水门汀、氢氧化钙水门汀、磷酸锌水门汀及阴性对照材料和阳性对照材料的细胞毒性,同时用传统的浸提液法测定这5种材料的细胞毒性。结果:牙本质屏障法测定的5种材料的细胞相对活性(%)分别为89.1±3.6、81.8±3.7、96.4±2.8、96.2±1.8、74.5±2.8;浸提液法测定的5种材料的浸提原液细胞相对活性(%)分别为35.6±5.2、72.9±4.3、91.5±1.3、90.2±2.6、59.3±2.6。结论:牙本质屏障可以显著减少充填材料对细胞的毒性作用,牙本质屏障法更能反映充填材料的体内细胞毒性。     

Coping and optimism in relation to dental health behaviour--a study among Finnish young adults

Our aim in this paper was to investigate active coping in relation to optimism, dental health behavior and self-reported dental health among 31-yr-old men and women born in Northern Finland in 1966. Connecting coping strategies and optimism with health behavior is an unexplored approach in dentistry, even though both coping strategies and optimism are known to be associated with many health outcomes. The data were based on a postal questionnaire, which was sent to the Northern Finland 1966 Birth Cohort at age 31 yr (n = 11 541). The number of replies was 8690, with a 75.3% response rate. Active coping was measured using the Ways of Coping Checklist and optimism using a revised Life Orientation Test. Prevalence proportion ratios were estimated by applying a log-binomial regression models. The results showed a correlation between active coping and optimism. Both active coping and optimism were related to different dental health behaviors. The effect of active coping on dental health behavior disappeared by adjusting for optimism, education and gender. The results support the previous findings that active coping acts as a mediator between optimism and health. Optimism was also related to self-reported dental health, which supports the comprehensiveness of optimism as a determinant for health.     

A systematic review of musculoskeletal disorders among dental professionals

Abstract:  Musculoskeletal problems have become a significant issue for the profession of dentistry and dental hygiene. This review provides a detailed examination and discussion regarding the prevalence of musculoskeletal disorders (MSD) in dental personnel and possible causative factors. All research studies or literature reviews, which have reported on the prevalence of musculoskeletal symptoms and/or potential risk factors for this problem in dentists, dental hygienists and dental students, were selected for inclusion. Our literature suggests that the prevalence of general musculoskeletal pain ranges between 64% and 93%. The most prevalent regions for pain in dentists have been shown to be the back (36.3–60.1%) and neck (19.8–85%), while the hand and wrist regions were the most prevalent regions for dental hygienists (60–69.5%). Interestingly, we found that studies on MSDs among dental and dental hygiene students are quite limited. Many risk factors have been identified, including static and awkward posture and work practices. Overall, the review suggests that musculoskeletal problems represent a significant burden for the dental profession. More research in the form of larger studies is urgently required, to help more clearly elucidate the development of this important issue for dental hygienists and dental hygiene students.     

Nordic dentists' opinions on the safety of amalgam and other dental restorative materials

The safety of amalgam and other restorative materials has caused concern among dental patients in recent years. The aim of this study was to obtain information on dentists' perceived competence in handling different filling materials and their opinions on the safety of these. A random sample of practising dentists in Denmark, Finland, Norway, and Sweden received a mail question-naire in spring 1990. Answers were received from 1732 dentists (65%). The study showed that the respondents believed that their theoretic knowledge and clinical skills were generally at a high level regarding restorative materials. The risks of the side-effects of gold, ceramic materials, and glass ionomer were considered to be low by about 90% of the respondents. Amalgam was considered to be significantly more hazardous by the Swedish respondents than the others. Interestingly, composite was considered to be associated with a high risk of side-effects by about half of the dentists in all Nordic countries. The dentists' opinions were not found to be greatly influenced by their sex, age, or place of residence but rather by their country and service sector. Against the background of the present lack of scientific evidence on the hazardousness of amalgam or other restorative materials for patients' general health, these findings indicate that dentists are influenced by discussions in the mass media about dental treatment and materials and, of course, by the guidelines given by the health authorities in their own countries. Few dentists were shown to be concerned about occupational risks associated with the use of amalgam, and they had not had their own amalgam fillings replaced. Thus, Nordic dentists seem prepared to continue to use amalgam as one of several dental restorative materials while waiting for technically and biologically more satisfactory ones.