bluuebunny/crossref_metadata_2025_split huggingface dataset:
Community Water Fluoride Levels, Preschool Dietary Patterns, and the Occurrence of Fluoride Enamel Opacities
Authors: Williams J. Earl , Zwemer Jack D. 
Published: April 2007

AbstractThree hundred seventy‐four 12‐ to 14‐year‐old children were examined to determine modified tooth surface index of fluorosis (TSIF) scores, and to assess the association among fluoride enamel opacities and water fluoride levels, preschool dietary patterns, and dentifrice consumption. The subjects included boys and girls of both black and white races who reported life‐long residence in either Augusta or adjoining Richmond County. “City” children had communal water consistently fluoridated at levels of 0.9 to 1. 2 ppm. “County” children had water variably fluoridated at levels of 0.2 to 0.9 ppm. TSIF scores were recorded on each included tooth and the highest TSIF tooth score was noted for each subject. The frequency of TSIF scores in all subjects was analyzed for dental arch symmetry and for association with city/county residence. The frequency of TSIF scores then was analyzed separately for “city” children and “county” children for an association with race, gender, preschool dietary habits, and dentifrice ingestion. Chi‐square analysis revealed that higher TSIF scores were associated with city children significantly more than with county children. There was no association of TSIF scores either in the city children or the county children with respect to gender, race, preschool dietary patterns, or dentifrice ingestion. TSIF scores were bilaterally symmetrical, but were higher in the maxillary arch than in the mandibular arch.
A Simplified Hypoplasia Index
Authors: Silberman Stephen L. , Trubman Aaron , Duncan William K. , Meydrech Edward F. 
Published: April 2007

AbstractA simplified hypoplasia index for deciduous teeth has been developed. The index utilizes a two‐digit system to signify the type and severity of the hypoplastic lesion. The types of lesions recorded are primary canine hypoplasia (PCH) and linear enamel hypoplasia (LEH). The severity ranges from minimal to severe and accounts for the presence of dental caries, dental restorations, and recurrent caries. To determine the reliability of the index, two tests were conducted. The first measure was a repeat reliability coefficient (test‐retest) to calculate the stability of the instrument. This measure was calculated for two populations by two examiners under the same examination conditions and exams were conducted seven weeks apart. The second measure calculated the interrater reliability (standardization). Test results were analyzed by employing the Pearson product moment correlation. The repeat reliability coefficients were. 75 (P≤.0001) and. 74 (P≤.0001). The interrater reliability coefficient was .87 (P≤.0001). These data seem to indicate that the index is reliable over time and between examiners.
Infection Control in the Indian Health Service Dental Program: Estimated Costs and Effects on Productivity
Authors: Broderick Eric B. 
Published: April 2007

AbstractThe dental literature contains many recommendations defining standards for infection control. Little information is available, however, documenting the cost of implementing these standards. This article describes the cost incurred by the Indian Health Service Dental Program in the Oklahoma area between 1985 and 1988 for infection control. During this period, comprehensive infection control recommendations were published for oral health programs serving Native Americans and data were collected on supply utilization. While productivity data were collected for that same time period do not support the premise that infection control practices lead to decreased clinical productivity, infection control supply costs did increase over fourfold during this period.
Oral Disease Beliefs, Behaviors, and Health Status of Korean‐Americans
Authors: Lee Josephine , Kiyak H. Asuman 
Published: April 2007

AbstractPrevious research with other ethnic minorities has shown that culture and age cohort, as well as language and economic limitations, act as barriers to obtaining dental care and maintaining good oral health. This study compared self‐reported oral health attitudes, self‐efficacy, and dental practices of 20 younger and 23 elderly Korean‐Americans. Oral assessments were also conducted to determine plaque and gingival status, and root and coronal caries. Significant differences emerged in health self‐efficacy (P < .01) and preventive health orientation (P < .002). Elderly had fewer teeth (P < .0001), more decayed and filled root surfaces (P < .05 and P < .004, respectively), and more decayed and filled coronal surfaces (P < .001 and P < .03). Both groups showed higher levels of distal and mesial plaque than occlusal and cervical plaque; however, the elderly had higher rates of both (P < .0001). Gingival status was also worse for the elderly, on distal and mesial (P < .01), facial (P < .01), and lingual (P < .01) surfaces. These differences are striking, since the elderly reported visiting the dentist more recently (P < .0001); but most of these visits were for prosthodontic and emergency care. Better preventive dental care and education are necessary for elderly immigrants who have not been exposed to preventive dentistry in their home countries.
Supply Decisions among Dentists Working within a Fixed‐fee System of Dental Care Provision
Authors: Grytten Jostein , Hoist Dorthe , Grytten Linda 
Published: April 2007

AbstractIn Norway fees for dental treatment did not increase at the same rate as prices for other goods and services during the 1980s. The aim of this study was to examine how this decrease in fees in real terms has influenced dentists' work decisions with respect to supply of services. Data on characteristics of the dentist and the dental practice were collected for 1979, 1984, and 1986. The dependent variable was supply of dental services, measured as the number of patient care hours worked per annum. The hourly fee for dental care was equivalent to dentists' hourly wage rate. Supply increased as fees decreased. This could be explained either as a response of the patient or the dentist to reduced fees. Although the data did not give conclusive evidence as to which effect was most important, the authors have put forward the view that the main effect was dentists' response to reduced fees. The main argument put in favor of this view is that dentists have an overall knowledge of the effect of a change in fees on their income. The impact of a change in fees is much greater on the provider who supplies the services to many individuals over a long period of time, than on an individual consumer who buys the services once or twice a year. It was concluded that, in the short run, a fixed‐fee schedule may not be very effective in limiting costs for dental care.
Improving Dental Epidemiologic Data Collection with Computers
Authors: Joshi Anil , McDermott Susan , Marcus Philip , Douglass Chester W. , Jette Alan 
Published: April 2007

AbstractA computerized dental data recording system (DDRS) was developed for the New England Elder Dental Study to improve data quality and increase field staff efficiency. The DDRS displays video screens similar to traditional paper forms to record data on corona) and root caries, dentate and denture status, subacute bacterial endocarditis screening, gingival bleeding, calculus, and periodontal attachment level. DDRS provides facilities for date and exam‐component time tracking, on‐tine contextual comments, random record retrieval, editing, data backup, and data output in various data formats. This study compared the DDRS with a paper‐form system for data entry accuracy. Dental caries and periodontal disease measurement data from 38 subjects were recorded on paper forms and independently entered using DDRS. The DDRS identified 150 illogical data errors, 39 inconsistent data errors, 7 invalid data and 34 miscellaneous data errors. Four technicians with field experience using both paper forms and DDRS reported time savings using DDRS in the field. DDRS has the potential for additional time savings by minimizing the time for data coding, cleaning, and management. Results demonstrate that DDRS could improve the quality of oral epidemiologic data by mandating strict adherence to protocols, preventing errors, and increasing field efficiency.
Utilization in Alberta's Universal Dental Plan for the Elderly, 1974‐91
Authors: Lewis Donald W. , Thompson G. W. 
Published: April 2007

AbstractSince 1973 the government of Alberta, a Canadian province of 2.4 million people, has funded a dental care plan for all residents over 64 years old and their dependents. It is the only dental plan in North America that covers all seniors and their dependents residing in a state or province. Under this plan, just over 270,000 persons (in 1990–91) are eligible for comprehensive, premium‐free dental services provided by dentists and denturists in private practice on a fee‐for‐service basis. The plan's design, administration, utilization, and costs are reviewed. Utilization increased from 27 percent of eligibles using the plan in 1974–75 to 44 percent in 1990–91, and the mean number of services per user rose from 4.9 to 6.9 during the same time period. Although the cost per eligible person has increased about 200 percent, from Canadian (C) $42 to C $131, these costs only began to exceed the rate of inflation in 1986–87. Even though just 12 percent of the two main providers participating in the plan are denturists, nearly 22 percent of plan patients attended denturists rather than dentists for their complete dentures. Fees paid to dentists by the plan have decreased over time relative to the standard fees for the various services listed annually in the Alberta Dental Association fee guide. The apparent growth of direct additional billing by dentists of plan users to recover the difference between their usual fees and those paid by the plan and the effects of greater plan utilization are discussed, as are future potential difficulties in the plan's administration.
Eligible Veterans' Choice Between VA‐covered and Non‐VA‐covered Dental Care
Authors: Gilbert Gregg H. , Branch Laurence G. , Longmate Jeffrey 
Published: April 2007

AbstractVeterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy‐one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non‐VA systems, to characteristics of the VA delivery system itself, to need for treatment.
Fluoride Concentrations in Human and Rat Bone
Authors: Eble Dennis M. , Deaton Thomas G. , Wilson Frank C. , Bawden James W. 
Published: April 2007

AbstractThe most recent report on fluoride concentrations ([f]) in human bone was published over a decade ago. Such data are of interest in the context of changing patterns in systemic fluoride exposure. In the study reported here, bone samples were collected from 24 human subjects who underwent orthopedic surgery. Medical histories and the best possible life‐time systemic fluoride exposure information were obtained from each subject. Bone samples were assayed for fluoride concentration using the acid diffusion, ion selective electrode method. For ash from whole bone, the lowest value was 378 ppm in a 16‐year‐old subject, and the highest value was 3,708 ppm in a 79‐year‐old person. Fluoride concentrations in bone were significantly correlated with age (r=.62). The regression line intercept at birth was 442 ppm, and the slope was 22 ppm per year. When measured separately, trabecular bone ash fluoride concentrations were significantly higher than the corresponding cortical bone values. Trabecular and cortical bone samples from rats' drinking water containing 75 ppm F were assayed for F. The mean trabecular bone fluoride concentration was significantly higher than the mean cortical bone concentration. There was close agreement between F assay results using a modification of the acid diffusion method and the method originally reported by Singer and Armstrong. The human bone ash [F] values reported in this study are similar to those reported from other North American subjects over the last three decades. These findings are of interest in the context of evidence indicating increased systemic fluoride exposure in the United States population. They may also be considered in efforts to evaluate the relevance of the National Institute of Environmental Health Sciences fluoride carcinogenesis study.
Mercury in Dental Amalgam‐a Public Health Concern?
Authors: Flanders Raymond A. 
Published: April 2007

AbstractDental amalgam has been the subject of intermittent controversy since it was introduced into dental practice approximately 150 years ago. The controversy has centered on the use of mercury in dental amalgam and the potential health implications to dental patients and dental health professionals from mercury exposure. In recent years the debate over the use of dental amalgam has intensified due to several articles in professional journals and media coverage by television and the press. This paper reviews the recent literature regarding dental amalgam, describes the activities of the antiamalgamists, examines the alternatives to dental amalgam, and reviews the recommendations for additional research. The existing scientific evidence does not demonstrate that mercury in dental amalgam poses a public health hazard. However, researchers on both sides of the controversy agree that much remains to be examined about the health implications of dental amalgam and that the subject merits continued research.
FDA Regulation of OTC Oral Health Care Drug Products
Authors: Rippere Jeanne L. 
Published: April 2007

AbstractThe history of the involvement of the Food and Drug Administration in the regulation of over‐the‐counter (OTC) drugs is reviewed. The development of monographs containing standards for drugs, the function of the advisory panels, and the classification of dental drug products are explained. Examples of ingredients in each category are given. The current opinion of the FDA concerning antiplaque and antigingivitis claims is also discussed.
FDA Regulation of Dental Devices: Past, Present, and Future
Authors: Tylenda Carolyn A. 
Published: April 2007

AbstractThe organization of the Food and Drug Administration as related to dental devices is described. The classification according to safety and efficacy of devices is described and examples are given. The process of submitting a Premarket Notification [(510(k)] for class I and II devices, a Premarket Approval (PMA) for class III devices and an Investigational Device Exemption (IDE) are described. The clinician is told how to report problems with medical devices.
Interactions as Seen by an Industry Representative among the FDA, the ADA, and Industry in Preparing a Restorative Material for Market
Authors: Dougherty Emery W. 
Published: April 2007

AbstractThe regulation of a restorative material in the international and the American markets is discussed. The 510(k) process of approval by the Food and Drug Administration allows marketing of safe, effective, and improved materials in the shortest time at the lowest cost. The American Dental Association contributes to developing consensus performance standards in the United States. Acceptance of International Standards Organization standards is discussed.
An allozyme study of sexual and vegetative regeneration in Hieracium pilosella
Authors: Bruun Hans Henrik , Scheepens J.F. , Tyler Torbjörn 
Published: April 2007

Allozyme markers were used to fingerprint clones of the grassland plant Hieracium pilosella L. and, by inference, to estimate the relative importance of sexual and vegetative reproduction in a population. Field studies in populations of clonal plant species have often reported negligible or absent recruitment from seed. In contrast, studies of genetic markers have found substantial clonal diversity in populations, suggesting recruitment of new genets into established populations. Our results showed that H. pilosella regenerates from seed both within and between dense clonal patches. Two sites differing in environmental conditions were sampled to investigate how the balance between seed-derived and stolon-derived recruitment changes with biotic and abiotic stress. In a relatively drought-prone site on a south-facing slope, the balance was shifted towards recruitment from seed, compared with a mesic site in which vegetative regeneration was more important.
A novel bifunctional N-acetylglutamate synthase-kinase from Xanthomonas campestris that is closely related to mammalian N-acetylglutamate synthase
Authors: Qu Qiuhao , Morizono Hiroki , Shi Dashuang , Tuchman Mendel , Caldovic Ljubica 
Published: April 2007

Abstract

Background
In microorganisms and plants, the first two reactions of arginine biosynthesis are catalyzed by N-acetylglutamate synthase (NAGS) and N-acetylglutamate kinase (NAGK). In mammals, NAGS produces an essential activator of carbamylphosphate synthetase I, the first enzyme of the urea cycle, and no functional NAGK homolog has been found. Unlike the other urea cycle enzymes, whose bacterial counterparts could be readily identified by their sequence conservation with arginine biosynthetic enzymes, mammalian NAGS gene was very divergent, making it the last urea cycle gene to be discovered. Limited sequence similarity between E. coli NAGS and fungal NAGK suggests that bacterial and eukaryotic NAGS, and fungal NAGK arose from the fusion of genes encoding an ancestral NAGK (argB) and an acetyltransferase. However, mammalian NAGS no longer retains any NAGK catalytic activity.

Results
We identified a novel bifunctional N-acetylglutamate synthase and kinase (NAGS-K) in the Xanthomonadales order of gamma-proteobacteria that appears to resemble this postulated primordial fusion protein. Phylogenetic analysis indicated that xanthomonad NAGS-K is more closely related to mammalian NAGS than to other bacterial NAGS. We cloned the NAGS-K gene from Xanthomonas campestis, and characterized the recombinant NAGS-K protein. Mammalian NAGS and its bacterial homolog have similar affinities for substrates acetyl coenzyme A and glutamate as well as for their allosteric regulator arginine.

Conclusion
The close phylogenetic relationship and similar biochemical properties of xanthomonad NAGS-K and mammalian NAGS suggest that we have identified a close relative to the bacterial antecedent of mammalian NAGS and that the enzyme from X. campestris could become a good model for mammalian NAGS in structural, biochemical and biophysical studies.
Efficient pairwise RNA structure prediction using probabilistic alignment constraints in Dynalign
Authors: Harmanci Arif Ozgun , Sharma Gaurav , Mathews David H 
Published: April 2007

Abstract

Background
Joint alignment and secondary structure prediction of two RNA sequences can significantly improve the accuracy of the structural predictions. Methods addressing this problem, however, are forced to employ constraints that reduce computation by restricting the alignments and/or structures (i.e. folds) that are permissible. In this paper, a new methodology is presented for the purpose of establishing alignment constraints based on nucleotide alignment and insertion posterior probabilities. Using a hidden Markov model, posterior probabilities of alignment and insertion are computed for all possible pairings of nucleotide positions from the two sequences. These alignment and insertion posterior probabilities are additively combined to obtain probabilities of co-incidence for nucleotide position pairs. A suitable alignment constraint is obtained by thresholding the co-incidence probabilities. The constraint is integrated with Dynalign, a free energy minimization algorithm for joint alignment and secondary structure prediction. The resulting method is benchmarked against the previous version of Dynalign and against other programs for pairwise RNA structure prediction.

Results
The proposed technique eliminates manual parameter selection in Dynalign and provides significant computational time savings in comparison to prior constraints in Dynalign while simultaneously providing a small improvement in the structural prediction accuracy. Savings are also realized in memory. In experiments over a 5S RNA dataset with average sequence length of approximately 120 nucleotides, the method reduces computation by a factor of 2. The method performs favorably in comparison to other programs for pairwise RNA structure prediction: yielding better accuracy, on average, and requiring significantly lesser computational resources.

Conclusion
Probabilistic analysis can be utilized in order to automate the determination of alignment constraints for pairwise RNA structure prediction methods in a principled fashion. These constraints can reduce the computational and memory requirements of these methods while maintaining or improving their accuracy of structural prediction. This extends the practical reach of these methods to longer length sequences. The revised Dynalign code is freely available for download.
Statistical significance of quantitative PCR
Authors: Karlen Yann , McNair Alan , Perseguers Sébastien , Mazza Christian , Mermod Nicolas 
Published: April 2007

Abstract

Background
PCR has the potential to detect and precisely quantify specific DNA sequences, but it is not yet often used as a fully quantitative method. A number of data collection and processing strategies have been described for the implementation of quantitative PCR. However, they can be experimentally cumbersome, their relative performances have not been evaluated systematically, and they often remain poorly validated statistically and/or experimentally. In this study, we evaluated the performance of known methods, and compared them with newly developed data processing strategies in terms of resolution, precision and robustness.

Results
Our results indicate that simple methods that do not rely on the estimation of the efficiency of the PCR amplification may provide reproducible and sensitive data, but that they do not quantify DNA with precision. Other evaluated methods based on sigmoidal or exponential curve fitting were generally of both poor resolution and precision. A statistical analysis of the parameters that influence efficiency indicated that it depends mostly on the selected amplicon and to a lesser extent on the particular biological sample analyzed. Thus, we devised various strategies based on individual or averaged efficiency values, which were used to assess the regulated expression of several genes in response to a growth factor.

Conclusion
Overall, qPCR data analysis methods differ significantly in their performance, and this analysis identifies methods that provide DNA quantification estimates of high precision, robustness and reliability. These methods allow reliable estimations of relative expression ratio of two-fold or higher, and our analysis provides an estimation of the number of biological samples that have to be analyzed to achieve a given precision.