bluuebunny/crossref_metadata_2025 huggingface dataset:
Posterior Cerebral Artery Territory Infarcts: Clinical Features, Infarct Topography, Causes and Outcome1
Authors: Brandt Tobias , Steinke Wolfgang , Thie Andreas , Pessin Michael S. , Caplan Louis R.
Published: April 2003

Only a few large series of posterior cerebral artery (PCA) stroke exist, and clinical features and causes have not been studied as extensively as in other vascular territories. The PCA syndrome includes more clinical signs than the well-known visual field deficits. Concomitant findings are frequently sensory, slight motor and neuropsychological deficits. Unilateral headaches are the common presenting symptom making complicated migraine an important differential diagnosis. Combined deep and superficial PCA territory infarcts involving the lateral thalamus are more frequent than commonly assumed and are mostly associated with sensory and reversible slight motor deficits. Occlusion of the precommunal PCA segment with associated paramedian midbrain infarction causes severe motor deficits, oculomotor signs, and decreased consciousness and has a poorer outcome than other PCA territory infarcts. Embolism from a cardiac or undetermined source is the leading mechanism accounting for up to half of the cases, whereas arterial embolism from significant proximal vertebrobasilar disease is less frequent. Local atherothrombotic stenosis or occlusion of the PCA is uncommon. In spite of thorough diagnostic evaluation, the etiology of PCA territory infarction cannot be determined in at least one quarter of patients. Among the rare causes of PCA territory infarction carotid artery disease is important while the significance of migraine remains controversial.
Intersonographer Reproducibility and Intermethod Variability of Ultrasound Measurements of Carotid Artery Stenosis: The Tromsø Study
Authors: Mathiesen Ellisiv B. , Joakimsen Oddmund , Bønaa Kaare H.
Published: April 2003

Background and Purpose: Knowledge of the reproducibility of a diagnostic method is important in order to evaluate its usefulness. Few studies have examined interobserver and intermethod agreement on ultrasound measurements of carotid stenosis. Methods: Intersonographer agreement on ultrasound measurements of carotid plaque morphology and the estimated degree of stenosis by three ultrasound methods were assessed in a random sample of 51 participants with stenotic carotid arteries selected from a population health survey. The degree of stenosis was assessed by measurements of velocity, lumen diameter reduction and cross-sectional lumen area. Intermethod agreement on the degree of carotid stenosis was also assessed. Results: Agreement on plaque echogenicity and heterogeneity was moderate (κ = 0.56 and κ = 0.60, respectively). The mean degree of stenosis and median absolute difference between observers of the estimated degree of stenosis by the velocity method were 46.3 and 10.8%, respectively. The corresponding values were 51.0 and 5.8% for the diameter method, and 57.1 and 7.2%, for the cross-sectional lumen method. The limits of agreement for intersonographer reproducibility varied between ±19.7 and 26.5%. For all methods, reproducibility increased with increasing degree of stenosis. Differences between the methods were large in low-grade stenosis but were acceptable in high-grade stenosis. Conclusions: Considerable differences in ultrasound measurement of stenosis, which could lead to different clinical conclusions, were regularly encountered no matter what ultrasound method was used.
Clinical Study on Recurrent Intracranial Aneurysms
Authors: Nakase H. , Kamada Y. , Aoki H. , Goda K. , Morimoto T. , Sakaki T.
Published: April 2003

The authors report 11 cases who underwent reoperations upon for recurrent aneurysms. The initial operations were performed on average 10.1 years earlier for subarachnoid hemorrhage (SAH). The patients’ mean age at the first surgery was 39.7 years. The locations were 9 internal carotid (IC)-posterior communicating artery (PC) and 2 anterior communicating artery (A-com) aneurysms. A residual aneurysmal neck after the first operation was observed in 3 of 10 cases confirmed by postoperative angiography. The primitive-type PC artery was seen in 8 of 9 recurrent IC-PC aneurysms. The recurrent manifestations were SAH in 9 cases. Clipping operations were conducted in 10 and ligation of the IC artery together with extracranial-intracranial bypass in 1 large IC-PC aneurysm. The present study demonstrated two risk factors for aneurysm recurrence, namely, young age and IC-PC aneurysms with a primitive-type PC. Furthermore, direct operation for recurrent aneurysm is often embarassing due to adhesions to the surrounding tissue as a sequela of the previous operation, hence understanding of the anatomical correlation between the old clip and the recurrent portion is important.
Antibodies to Beta2-Glycoprotein I in Ischemic Stroke
Authors: Fiallo Paolo , Tomasina Carlo , Clapasson Andrea , Cardo Paolo P.
Published: April 2003

Antibodies to β2-glycoprotein (β2-GPI) have been associated with recurrent thrombotic events in patients with systemic lupus erythematosus. The present study investigated the prevalence of antibodies to β2-GPI in an unselected group of patients with ischemic stroke. One hundred and twenty-one sera from patients with ischemic stroke and 174 control sera from patients with nonischemic neurological disorders (n = 43) and healthy subjects (n = 131) were tested for antibodies to β2-GPI by a solid-phase ELISA. Twenty-nine stroke patients (24%) had antibodies to β2-GPI. Of the 43 patients in the neurological control group, 2 were positive. For comparison between the groups, Fisher’s exact test was used for categorical variables and ANOVA for antibody titers. Antibody levels and frequencies of positivity were significantly different between the study groups. None of the sera from the healthy control group had abnormal antibody levels. When risk factors and associated diseases were taken into account, a marginal association was found between the presence of antibodies to β2-GPI and hypertension (p = 0.036). This study demonstrates a significant prevalence of antibodies to β2-GPI in an unselected stroke population.
A Case of Arrhythmia-Induced Transient Cerebral Hyperaemia
Authors: Carey Brian J. , Eames Penelope J. , Panerai Ronney B. , Potter John F.
Published: April 2003

Transient cerebral hyperaemia following an arrhythmia has not been previously demonstrated in humans. We report the effects of head-up tilt on a 78-year-old man with neurocardiogenic syncope. During tilt, an asymptomatic arrhythmia caused arterial blood pressure and transcranial Doppler-recorded cerebral blood flow velocity to fall markedly. Upon spontaneous resumption of sinus rhythm, cerebral blood flow velocity increased to values greater than those prior to the arrhythmia. This occurred prior to a full recovery of arterial blood pressure, indicating spontaneous transisent hyperaemia. Pressure-flow velocity graphs support current methods of measuring critical closing pressure and demonstrate a rise in critical closing and a fall in resistance-area product after the arrhythmia.
Risk Factors for Lacunar Infarcts
Authors: Besson Gérard , Hommel Marc , Perret Jean
Published: April 2003

Lacunar infarcts represent a stroke subgroup with controversial risk factors. Lacunar syndromes may be divided into two groups: the classic group (pure motor hemiplegia, pure sensory stroke, ataxic hemiparesis, dysarthria-clumsy hand syndrome, sensorimotor stroke) and the miscellaneous group including all other lacunar syndromes. We studied risk factors of 200 consecutive patients with symptomatic lacunar infarcts diagnosed by magnetic resonance imaging. This study tested whether lacunar infarcts represent a homogeneous subgroup of strokes or not. Using descriptive and bivariate statistics, we found that the prevalences of arterial hypertension and cigarette smoking are lower in the miscellaneous group. Analysis of variance shows a significant difference in age between subgroups without interaction of sex. Nevertheless, using multivariate analysis, we did not find a difference between subgroups. Thus, lacunar infarcts seem to be a homogeneous subgroup of strokes, and the miscellaneous group of lacunar infarcts may be included into the lacunar infarct group and not into the vertebrobasilar large-artery infarct group.
Vertigo and Gait Ataxia without Usual Signs of Lateral Medullary Infarction: A Clinical Variant Related to Rostral-Dorsolateral Lesions
Authors: Kim Jong S.
Published: April 2003

Isolated vertigo and ataxia have not been reported as manifestations of lateral medullary infarction. The author describes 3 patients with lateral medullary infarction who presented with almost isolated vertigo and gait ataxia without usual signs/symptoms of lateral medullary infarction such as facial/hemibody sensory changes, dysphagia, hoarseness, hiccup, limb ataxia, and Horner sign. Brain MRI showed small infarcts selectively involving the most dorsolateral portion of the rostral medulla that corresponds to the vestibulocerebellar pathway. These patients illustrate that lateral medullary infarction may present as an isolated vertigo and gait ataxia. Clinicians should be aware of this clinical variant, because these patients may be misdiagnosed as having labyrinthine disorders.
CT and MRI in Acute Hemorrhagic Stroke
Authors: El-Koussy Marwan , Guzman Raphael , Bassetti Claudio , Stepper Frank , Barth Alain , Lövblad Karl-Olof , Schroth Gerhard
Published: April 2003

We report the case of a woman presenting with an acute onset of hemiplegia. MRI was performed and showed a hyperintense mass on diffusion-weighted imaging, with areas of high signal intensity on T2* imaging and T2/PD imaging. T1-weighted imaging showed a more inhomogeneous lesion with a central isointense part corresponding to the acute clot, as well as a peripheral crescent of hypointense plasma; since another mass lesion could not be acutely excluded, computed tomography was performed immediately afterwards, showing a hyperdense hematoma. The patient was taken to the neurosurgical operating theater, where she underwent decompressive craniotomy and evacuation of the hematoma.
Role of Primary Care Providers in the Delivery of Genetics Services
Authors: Hayflick Susan J. , Eiff M. Patrice
Published: April 2003

Fruits of the Human Genome Project are already transforming health care. Primary care providers, regardless of specialty, will need to integrate new genetics knowledge into routine practice in order to fulfill their role in genetics services delivery. Unfortunately, few are prepared for this revolution, and current educational efforts are inadequate. To effect the changes that are needed, we must teach genetics as an integrative discipline at all stages of professional education and emphasize the value of this knowledge to practice.
To Screen or Not to Screen:When Should Screening Be Offered?
Authors: Bowman JamesE.
Published: April 2003

Early testing for phenylketonuria, Tay-Sachs disease, and sickle hemoglobin are briefly summarized. The advent of prenatal diagnosis and DNA testing introduced different ethical issues. The out-of wedlock birth rate in the African American community in Chicago is about 83% – thus often obviating the cooperation of the putative mate for genetic testing. Post testing counseling only for those pregnant women who are positive for sickle hemoglobin has been suggested for a busy obstetrician’s office, because the long-established triad of education, testing and counseling in prenatal testing may not be feasible in an obstetrician’s office. DNA testing for a large number of genetic disorders is now possible – thus compromising pretesting education and informed consent. Although it has been suggested that genetic information be denied to insurance carriers, such a practice also would eliminate family history and other pertinent information from the chart. One solution is to radically change our inequitable health care system.
Toward a Framework of Mutualism: The Jewish Community in Genetics Research
Authors: Rothenberg KarenH. , Rutkin AmyB.
Published: April 2003

The ability of scientists to identify genes believed to cause inherited diseases, including familial cancers, has become considerably refined over the last two decades because of technological breakthroughs. When research published in 1995 appeared to show that genetic mutations linked to breast and ovarian cancers (BRCA1 and BRCA2) occur more frequently in Jews of Eastern European descent than in the general population, the first response among Jewish women was to rush to participate in research. When a gene linked to colorectal cancer was identified in 6% of the Jewish population in 1997, however, press reports began to carry inaccurate and inflammatory headlines about Jewish ‘mutant gene carriers’, raising fears of discrimination and loss of privacy. Some rabbis and other leaders of the Jewish community began to quietly advise Jews not to get a genetic test or participate in genetics research until legal protections against discrimination are established. At the present time, a subtle tension is developing between the Jewish tradition of encouraging the acquisition of knowledge, particularly medical knowledge (exemplified by the community’s successful collaboration with genetic researchers when tests for Tay-Sachs disease were developed in the 1970s) and the fear of potential discrimination or stigmatization. In order to address this tension, and ensure the continued participation by the Jewish community in critical genetics research, a framework based on the mutual interests of researchers and participants should be formulated. Such a framework of dialogue and policy would be useful in building an important element of trust for the Jewish community and other distinct communities who are sought for such research.
Genetic Education to Diverse Communities Employing a Community Empowerment Model
Authors: Mittman IlanaSuez
Published: April 2003

Lack of equity in access to health care, in general, and genetic services in particular, places communities of color at a distinct disadvantage when considering the rapidly evolving genetic technology. Much of this disparity is owed to lack of trust and credibility in the genetic care system as well as multiple ethnocultural barriers to services. This paper presents a 3-year community outreach demonstration project in genetic education. The project employed the premise that the empowerment of the target communities to take active part in their genetic education, with attention to a wide array of the community’s health care needs, is the most efficacious manner in which to provide genetic education to underserved communities.
Privacy and Antidiscrimination Issues: Genetics Legislation in the United States
Authors: Hodge Jr. JamesG.
Published: April 2003

There are strong incentives for individuals to undergo genetic tests. Genetic information can improve clinical analysis, facilitate medical research, improve the public health, and enhance individual autonomy. However, the rise of genetic information within the health information infrastructure also presents risks to individual privacy and threats in the form of discrimination. While the federal government contemplates genetic privacy legislation, at least 34 states have passed genetic privacy and anti-discrimination legislation. This article examines the scope, intent, and effects of such state legislation. While some state genetics laws are appropriately tailored to the legislators’ intentions, some laws do not properly consider the science of genetic testing or may be over-broad or under-inclusive toward regulating in the interests of preserving individual privacy or prohibiting genetic discrimination by health insurers, employers, and others. Future guidance concerning state genetics legislation may flow from the NIH-funded project, entitled ‘Genetics Legislation: Syntax, Science, and Policy’, that will assist state and federal legislators to legislate effectively concerning genetic privacy.
Hereditary Nonpolyposis Colorectal Cancer: An Approach to the Selection of Candidates to Genetic TestingBased on Clinical and MolecularCharacteristics
Authors: Viel Alessandra , Genuardi Maurizio , Lucci-Cordisco Emanuela , Capozzi Eugenia , Rovella Valentina , Fornasarig Mara , Ponz de Leòn Maurizio , Anti Marcello , Pedroni Monica , Bellacosa Alfonso , Percesepe Antonio , Covino Marcello , Benatti Piero , Del Tin Laura , Roncucci Luca , Valentini Maurizio , Boiocchi Mauro , Neri Giovanni
Published: April 2003

Objective: Identification of clinical and molecular characteristics associated with constitutional MLH1 and MSH2 mutations and definition of a stepwise strategy for the selection of colorectal cancer (CRC) patients amenable to MLH1 and MSH2 genetic testing. Methods: 90 unrelated CRC patients were initially selected on the basis of either familial or early onset occurrence of CRC. They were screened for the presence of constitutional MLH1 and MSH2 mutations and for microsatellite instability (MSI). Results: 16 pathogenetic mutations (9 MLH1 and 7 MSH2) were identified in 41% of Amsterdam hereditary nonpolyposis colorectal cancer (HNPCC) families, 5% of suspected HNPCC families, and 14% of sporadic early-onset CRC patients. The presence of the mutations correlated with MSI, with early age of onset and proximal location of the tumor, and with the presence of some extracolonic tumors of the HNPCC spectrum and/or multiple tumors in the family. Conclusions: Evaluation of clinical and molecular characteristics is useful for the identification of candidates to MLH1 and MSH2 mutational analysis and allows the application of a rational approach to genetic testing.
Ethical Issues in Molecular Screening for Heterozygous Familial Hypercholesterolemia: The Complexity of Dealing with Genetic Susceptibility to Coronary Artery Disease
Authors: Gaudet Daniel , Gagné Claude , Perron Patrice , Couture Patrick , Tonstad Serena
Published: April 2003

Familial hypercholesterolemia (FH) is one of the most common inherited metabolic diseases, and is associated with an increased cardiovascular risk. The diagnosis of FH is based on clinical criteria, but molecular DNA testing is available, and has proven to be helpful in risk assessment. In addition, new technologies could be applied to FH, such as high-density DNA probe arrays and gene therapy. The use of genetic information, however, raises specific ethical concerns which indicate that DNA testing for FH should not be performed blindly. Before consenting to molecular testing, an individual must really understand FH, what risks it involves for himself as well as his family and community, and what the treatment entails. Since the cardiovascular risk of FH patients is affected by other susceptibility genes and environmental factors, an individual should be able to assess the impact of this additional risk on his health outcome. In this regard, the ethical issues raised by a simple trait such as FH may help define a community genetic approach for a complex trait such as coronary artery disease.
Genetic, Epidemiologic and Social Features of Colour Blindness
Authors: Tagarelli A. , Piro A. , Tagarelli G.
Published: April 2003

Red-green colour blindness is an inherited defect which shows interesting epidemiologic and social features. Its mean frequency within the indigenous population of Calabria (Southern Italy) was found to be 5.25%, one of the highest in continental Italy, showing a decreasing trend from the province of Cosenza (Northern Calabria, 6.23%), to the province of Catanzaro (Central Calabria, 4.65%) and the province of Reggio Calabria (Southern Calabria, 3.43%). A similar trend has not been previously recognized, according to the recent literature, because no other region has been fully screened. The mean frequency (7.40%) of red-green colour blindness in the Albanian ethnic minority in Calabria is significantly different from that of the indigenous population, and this minority does not have the protanomalous phenotype. Screening showed that 96% of the colour-blind students attending middle school and 65% of the colour-blind university students are not aware of their anomalous vision status. Thus, screening during the school years would greatly help affected students to choose their future professional orientation.
The Epidemiology of Myotonic Dystrophy in Northern Ireland
Authors: Magee Alex , Nevin Norman C.
Published: April 2003

Multiple sources of ascertainment were used to identify families with myotonic dystrophy in Northern Ireland. A total of 59 families with 188 living affected members were identified. The prevalence rate was 119.5 × 10–6 in a total population of 1.5 million, a rate similar to neighbouring communities. Information about the natural history of the disease in these families enabled analysis of age of onset, fertility, fitness and age at death.
Time Trends in Caries Experience of 6- and 12-Year-Old Children of Different Socioeconomic Status in The Hague
Authors: Truin G.J. , König K.G. , Bronkhorst E.  M. , Frankenmolen F. , Mulder J. , van ’t Hof M.A.
Published: April 2003

The caries experience among 6- and 12-year-old children in the The Netherlands from the mid seventies showed a continued decreasing trend. A halt in the decline of caries experience of the primary dentition of 6-year-olds occurred after 1983, whereas among 12-year-old children the decrease in mean DMFS values continued in the period 1980–1989. The 1996 survey in The Hague showed that the decline in caries in 12-year-old native children of low socioeconomic status (SES) has come to an end (average DMFT of 1.1). However, in medium- and high-SES groups, the percentages of caries-free children have continued to rise. Of the medium-SES 6- and 12-year-old children, 79 and 89% were caries-free, respectively; in the high-SES children the respective figures were 84 and 86%. A DMFT of 0.3 in 12-year-olds of medium and high SES was found, the general value was 0.7 and 74% with zero caries experience.
Comparison of the Efficacy of Three Different Chlorhexidine Preparations in Decreasing the Levels of Mutans Streptococci in Saliva and Interdental Plaque
Authors: Twetman S. , Petersson L.G.
Published: April 2003

The aim of the present study was to evaluate and compare the effects of three different chlorhexidine (CHX)-containing preparations on mutans streptococci (MS) levels in interdental plaque and whole saliva. Ninety-three healthy schoolchildren (8–10 years old) with high scores of salivary MS were selected by a screening procedure and randomised into three equally sized groups. MS were enumerated at all mesial interdental sites of the first permanent molars with aid of a modified chairside technique. The patients were then treated three times within 2 weeks with either a 1% CHX/thymol-containing varnish (group A) or a 1% CHX gel (group B), or they were subjected to daily supervised toothbrushing with a 0.4% CHX dentifrice for 1 month (group C). Follow-up samples of saliva and plaque from the interdental sites were collected 1 and 3 months after termination of treatment. A statistically significant reduction of MS levels in saliva and interdental plaque was found in all groups after 1 month. The CHX-containing dentifrice (group C) was the most effective method in reducing MS levels in saliva, and a significantly stronger (p < 0.05) suppression was found after 1 and 3 months when compared with the gel and the varnish forms. The gel (group B) tended to be slightly more effective than the varnish (group A). In the interdental plaque, the reduction of MS was less marked than in the saliva, and the three groups exhibited MS reductions of similar magnitude (20%) and duration, persisting up to 3 months. However, a high proportion (approximately 50%) of all interdental sites were relatively unaffected by the treatments. In conclusion, our results suggest that the interdental MS colonisation was difficult to combat, irrespective of CHX preparation and method, while the salivary levels were more easily affected. Daily tooth-brushing with a CHX-containing dentifrice was more effective in reducing MS in saliva compared with the gel or varnish applications.
Trends in Caries Prevalence in Dutch Adults between 1983 and 1995
Authors: Kalsbeek H. , Truin G.  J. , van Rossum G.  M.  J.  M. , van Rijkom H.  M. , Poorterman J.  H.  G. , Verrips G.  H.
Published: April 2003

In 1995, a dental survey was performed among adults aged 25–54 in the Dutch city of ’s-Hertogenbosch. A similar study was performed in the same city in 1983 and the aim of the present study was to describe trends in oral health from 1983 to 1995. National data show that the percentage of edentulous persons aged 30–39 and 40–49 decreased from 11.3 to 3.3 and from 28.5 to 13.8, respectively, between 1984 and 1993/94. The same trend was found in ’s-Hertogenbosch. In persons with natural dentition under the age of 35 the mean number of DMFT decreased significantly between 1983 and 1995. In 1995 the mean number of FT was higher, and the mean numbers of DT and MT were lower than in 1983 in all age categories. It can be concluded that oral health in Dutch adults, as measured by caries prevalence, treatment level of caries and percentage of edentulous persons, improved significantly between 1983 and 1995.
Dental Caries Susceptibility in Mice Is Closely Linked to the H-2 Region on Chromosome 17
Authors: Suzuki N. , Kurihara Y. , Kurihara Y.
Published: April 2003

The generation of dental caries in humans is thought to be regulated by many intrinsic and social factors. In this study, we examined the effect of MHC on susceptibility to dental caries in mice. The mean carious score of BALB.K/Ola, a H-2 congenic strain in which the H-2 region derived from C3H/HeJ (H-2k/k) is introduced into BALB/cJ (H-2d/d), was markedly reduced as compared with that of its recipient strain (BALB/cJ). Mating experiments confirmed a strong genetic linkage between H-2 haplotype and caries susceptibility. These results demonstrate that one of the genetic factors of the susceptibility in the mouse is mapped within the H-2 region. This finding of a host genetic factor influencing the generation of dental caries will help in developing clinical preventive strategies.
Surface–Specific Electrical Occlusal Caries Diagnosis: Reproducibility, Correlation with Histological Lesion Depth, and Tooth Type Dependence
Authors: Huysmans M.-Ch.D.N.J.M. , Longbottom C. , Hintze H. , Verdonschot E.H.
Published: April 2003

Electrical conductance measurements are being used experimentally for occlusal caries detection. Recently, it was suggested to cover the fissure system with a conducting medium, resulting in a surface–specific measurement. It was the aim of this study to determine in vitro the reproducibility of this modified technique for occlusal caries in posterior teeth, to determine for a large study sample the correlation between the electrical measurements and histological lesion depth, and to evaluate the difference between results for premolars and molars. For the reproducibility determination, surface–specific electrical resistance measurements were made using a sample of 68 posterior teeth. Eight operators performed measurements on all teeth, and repeated measurements on 24 teeth. The validity study included the previous sample and the collected samples from two more studies, resulting in a total sample of 325 posterior teeth. One operator had performed electrical resistance measurements on all teeth in the sample. Reproducibility was good: mean Pearson's correlation coefficient 0.89 (±0.05) for interexaminer correlation, and 0.86 (±0.12) for intra–examiner correlation, using log (resistance) as the result parameter. The correlation coefficient between log(resistance) and histological lesion depth for the large sample was –0.78 for all teeth, –0.64 for premolars, and –0.73 for molars. The regression line for molars was located below the regression line for premolars: at a hypothetical histology score of 2.5 (a dentine caries threshold) the estimated resistance threshold would be 507 kΩ for premolars, and 233 kΩ for molars. Converted to Electronic Caries Monitor (ECM) readings, the difference is about 1.4 on the ECM scale. It was concluded that the in vitro reproducibility of the described surface–specific method for electrical resistance measurement is very good, even for inexperienced operators. The correlation between measurements and histological lesion depth is moderate to good. The method is sensitive to electrode area differences, which will result in different clinical cut–offs for caries diagnosis in premolar and molar teeth.
Enamel Erosion by Some Soft Drinks and Orange Juices Relative to Their pH, Buffering Effect and Contents of Calcium Phosphate
Authors: Larsen M.J. , Nyvad B.
Published: April 2003

The capability of a soft drink or a juice to erode dental enamel depends not only on the pH of the drink, but also on its buffering effect. As the latter is the ability of the drink to resist a change of pH it may add to the effects of the actual pH. The aim of the present study was to compare the pH and the buffering effect of various soft drinks with their erosive effects and the solubility of apatite. In 18 soft drinks, mineral waters and juices available on the Danish market, pH and the concentrations of calcium, phosphate and fluoride were determined. The buffering effect was determined by titration with NaOH. Human teeth (n = 54) covered with nail varnish except for 3×4–mm windows were exposed to 1.5 liters of the drink for either 7 days or 24 h under constant agitation. The depth of the erosions was assessed in longitudinal sections. The depth was found to vary greatly from 3 mm eroded by the most acidic drinks and fresh orange juice to only slightly affected surfaces by most of the mineral waters. The dissolution of enamel increased logarithmically inversely with the pH of the drink and parallel with the solubility of enamel apatite. Orange juice, pH 4.0, supplemented with 40 mmol/l calcium and 30 mmol/l phosphate did not erode the enamel as the calcium and phosphate saturated the drink with respect to apatite. Generally, the lower the pH the more NaOH was necessary to bring the pH to neutrality. In particular the buffering effect of the juice was high. For all drinks, no effect of their low fluoride concentrations was observed.
Dental Caries in Pre–School Children: Associations with Social Class, Toothbrushing Habit and Consumption of Sugars and Sugar–Containing Foods
Authors: Gibson S. , Williams S.
Published: April 2003

This project examined the relative significance of dietary sugars, toothbrushing frequency and social class as predictors of caries experience (caries vs. no caries) among 1,450 British pre–school children who took part in the National Diet and Nutrition Survey. This cross–sectional survey was based on a representative sample of children aged 1.5–4.5 years studied in 1992/3. Children were classified into four groups according to social class and toothbrushing habit. Diet/caries associations were examined for biscuits and cakes, sugar confectionery, chocolate confectionery and soft drinks, and the percentage of energy from non–milk extrinsic sugars, using data on amount and frequency of consumption from 4–day weighed dietary records. In stepwise logistic regressions, the strength of the association between social class and caries experience was twice that between toothbrushing and caries, and nearly three times that between sugar confectionery and caries (other dietary variables were not significant). The association of caries with sugar confectionery (both in amount and frequency) was only present among children whose teeth were brushed less than twice a day. Toothbrushing frequency appeared to have a stronger impact on caries prevention in non–manual compared with manual children. Household expenditure on confectionery was associated with caries only among children from the manual group. The findings suggest the hypothesis that regular brushing (twice a day) with a fluoride toothpaste may have greater impact on caries in young children than restricting sugary foods.
Detection of Early Interproximal Caries in vitro Using Laser Fluorescence, Dye–Enhanced Laser Fluorescence and Direct Visual Examination
Authors: Eggertsson H. , Analoui M. , van der Veen M.H. , González-Cabezas C. , Eckert G.J. , Stookey G.K.
Published: April 2003

This in vitro study evaluated the use of laser fluorescence (LF) for the detection of early interproximal carious lesions and whether the detection could be enhanced using a fluorescent dye (DELF). Direct visual examination (DV) was used for comparison. Eighty extracted teeth were used, arranged in 20 blocks, each block having 2 premolars and 2 molars, lined up in a simulated sextant situation. After cleaning with a microabrasion kit, a subcontact window on half of the surfaces (60) was exposed to Carbopol white–spot solution for 5 days. The teeth were remounted in stone and examined by three independent examiners. For LF and DELF an argon laser was used (mixed wavelength of 488 and 514 nm) viewed through glasses (excluding wavelength <520 nm). For DELF a sodium fluorescein dye (0.075%) was applied before examination. A clinical examination light was used for DV. The approximal surfaces were scored for lesion presence or absence. To verify lesion presence, the subcontact area was cut perpendicularly to the surface, stained with rhodamine B, and images were taken using a confocal microscope. The images were analyzed using a histogram program for lesion depth and image area. Lesions were present in 62 out of 120 approximal surfaces, with an average depth of 60 μm (range 17–190 μm). Sensitivity ranges for LF, DELF and DV were 56–74, 61–79 and 58–74%, and specificity ranges 67–78, 86–98 and 83–97%, respectively. With this model DELF compared favorably with DV and LF in sensitivity, but specificity was better for DELF and DV than for LF.
Altitude as a Risk Indicator of Dental Fluorosis in Children Residing in Areas with 0.5 and 2.5 mg Fluoride per Litre in Drinking Water
Authors: Rwenyonyi C.M. , Bjorvatn K. , Birkeland J.M. , Haugejorden O.
Published: April 2003

The purpose of this study was to assess the association between altitude and dental fluorisis among Ugandan children in two fluoride (F) districts while controlling for other factors related to fluorosis. A random sample of 481 children aged 10–14 years was examined for fluorosis using the Thylstrup and Fejerskov (TF) index. The prevalence and severity of dental fluorosis increased significantly with increase in altitude (900 vs. 2,200 m in the low– and 1,750 vs. 2,800 m in the high–F district) and in F concentration in the drinking water. In bivariate correlation analyses, F exposure from liquid (FEL), altitude, infant formula, vegetarianism and storing of drinking water in earthenware pots were significantly associated with the tooth prevalence of fluorosis (TPF), i.e. at a severity of TF score ≥1 (p<0.05); age and gender were not. The stepwise multiple linear regression explained 35 and 55% of the variance in TPF within the low– and high–F districts, respectively. The change in R2 due to FEL was 28 and 51% points compared with 5 and 4% points due to altitude. The significant effect of FEL and altitude was confirmed by multiple logistic regression analyses. Thus, although most of the variation in the prevalence and severity of dental fluorosis was explained by the F intake from liquid, altitude was a significant risk indicator after controlling for potential confounders.
Behaviour of Approximal Carious Lesions Assessed by Clinical Examination after Tooth Separation and Radiography: A 2.5–Year Longitudinal Study in Young Adults
Authors: Hintze H. , Wenzel A. , Danielsen B.
Published: April 2003

This study aimed to record and monitor over a 2.5–year period the occurrence of cavitation and lesion depth progression in approximal surfaces with radiographic caries at baseline. In total, 66 approximal sites (in 29 students), where at least one of the contacting surfaces had radiographic caries, were selected to take part in the study. A clinical examination undertaken before and after tooth separation in order to assess the presence/absence of cavitation was repeated every sixth month. To monitor lesion progression bite–wing radiographs were taken every sixth month, too. After each series of examinations, surfaces judged to be prone for disease progression were referred to operative caries treatment. In surfaces with radiographic dentinal caries at baseline the cavitation prevalence following tooth separation found at the various recall examinations ranged from 20 to 44%. In surfaces with radiographic enamel caries at baseline this prevalence ranged from 4 to 8% at the various recall examinations. In dentinal lesions found with an intact surface at baseline, the risk of cavitation development during the first 1.5–year period was assessed to be up to 22%. After this period no new cavitations were found in previously intact dentinal lesions. In intact enamel lesions the risk of cavitation formation was found to be 3% during the first 1–year period. After this period no new cavitations developed in previously intact enamel lesions. Three of 7 lesions, which showed radiographic caries progression from the outer one third to the inner two thirds of the dentine during the observation period, had intact surfaces at baseline. On the basis of these results it is recommended to re–examine carefully intact, dentinal lesions by repeated clinical examination after tooth separation and by radiography about 1–1.5 years after baseline.
Caries–Preventive Effect of Topical Amine Fluoride in Children with High and Low Salivary Levels of Mutans Streptococci
Authors: Brambilla E. , Gagliani M. , Felloni A. , García-Godoy F. , Strohmenger L.
Published: April 2003

The aim of the study was to assess the relationship between the salivary mutans streptococci (SMS) level and the effectiveness of a preventive intervention based on a biannual application of an amine fluoride solution (AmF). A total of 284 schoolchildren aged 6 years were recruited from eleven classes of a primary school in Milan and randomly assigned to an experimental (A) and a control group (B). SMS counts were obtained at baseline and caries incidence data (diseased, missing, filled teeth, DMFT) were recorded every 6 months for 5 years. The participants of the experimental group received application of an AmF 1% F– solution twice a year on the enamel surfaces of the first permanent molars for 5 years. Control group subjects received application of a placebo solution twice a year on the enamel surfaces of the first molars for the same period. The mean DMFT in the experimental and control groups were 0.56 and 0.22, respectively, at the beginning and 1.14 and 2.06 after 5 years. SMS data allowed children to be classified into low– (0–105 CFU/ml of saliva) and high– (>105 CFU/ml of saliva) SMS subjects. Survival analysis, performed on the first molar data split by SMS group, showed a significantly higher caries reduction in low–SMS experimental group subjects compared to low–SMS control group subjects after 5 years. No significant differences were found between the two high–SMS experimental and control groups. These findings indicate that the preventive effects of the treatment were significantly lower in subjects who had high SMS. It is concluded that the effectiveness of a simple and economical topical fluoride intervention applicable at a community level is significantly influenced by the SMS level of the subjects involved. Simple AmF preventive interventions, applied on low–SMS subjects, can give significant results in terms of caries reduction.
In vitro Effectiveness of Hand Excavation of Caries with the ART Technique
Authors: Smales R.J. , Fang D.T.S.
Published: April 2003

The purpose of this study was to evaluate the effectiveness of the atraumatic restorative treatment (ART) hand–instruments and of round steel burs for removing caries at the enamel–dentine junction (EDJ) in occlusal cavities prepared in 50 extracted permanent molars. The teeth were divided randomly into two equal groups for the two treatments provided by 1 operator. Stained but hard dentine was not removed. The teeth were then sectioned vertically, buccolingually through the prepared cavities to give 200 sections, each 500 μm thick, which were photographed (×1 magnification) before and after staining with a caries detector dye. Assessments were made (×3 magnification) of (a) the amount of brown–stained residual dentine, and (b) the amount of red dye–stained dentine present at the EDJ, using two sets of standards devised and transparencies arranged as six–category incremental rating scales. There was no statistically significant difference found between the two caries–removal methods for the amount of residual brown–stained dentine present (χ2 = 3.394, p = 0.64), but there was for the amount of red dye–stained dentine present (χ2 = 32.137, p<0.0001), although 57% of the ART and 80% of the steel bur sections had very little to mild red–dye staining present. Excavation of caries at the DJE appeared to be less effective with the ART technique, although the clinical implications of this may not be significant.
Inhibiting Action of Carbohydrates on the Growth of Fluorapatite Crystals
Authors: Matsumoto T. , Okazaki M. , Taira M. , Takahashi J.
Published: April 2003

Hydroxyapatite (HAp) and fluorapatite (FAp) were synthesized in the presence of carbohydrates (glucose, fructose, galactose and sucrose). X–ray diffraction analysis showed that the crystallinity of two FAp groups that were synthesized in the presence of glucose or sucrose decreased with the increase in carbohydrate content. In SEM photographs we found that the size of their crystals was small and the shape changed. However, FAp groups that were snythesized in the presence of fructose or galactose showed little change in their crystallinity and shape. Four carbohydrates had some influence on size, but not on shape or crystallinity when synthesizing HAp. These results suggest that glucose and/or sucrose has a chemical affinity to FAp and inhibits the growth of FAp crystals.
Digital Subtraction Radiography for Monitoring Dental Demineralization
Authors: Eberhard J. , Hartman B. , Lenhard M. , Mayer T. , Kocher T. , Eickholz P.
Published: April 2003

The aim of the present study was to evaluate the assessment of progression of demineralization by digital subtraction radiography. In each of 14 extracted human teeth, 2 approximal enamel demineralization lesions were induced in vitro to simulate dental caries. A modified tunnel preparation with glass ionomer fillings was performed on one lesion of every tooth as a model of caries inhibition. Every week, radiographs were obtained under standardized conditions over a period of 42 days. The radiographs were digitized and calibrated for grayscales. Reference landmarks were chosen and aligned for the different pictures by computer–assisted imaging to adjust the images for projective distortions. The images of the 7th, 14th, 21st, 28th, 35th and 42nd day were subtracted from the baseline radiograph. The mean value of gray values of the subtraction images was calculated and ANOVA tests for repeated measurements and paired t tests were used for statistical analysis. The results of the present study indicate that statistically significant gray level changes due to progression of demineralization could be detected in the radiographic images by subtraction analysis. Differences between glass ionomer–filled and nonfilled lesions failed to reach significance. The introduced method may have the potential to detect and document minute caries progression.
Similarity of Bacteriocin Activity Profiles of Mutans Streptococci within the Family When the Children Acquire the Strains After the age of 5
Authors: van Loveren C. , Buijs J.F. , ten Cate J.M.
Published: April 2003

It has been shown that there is a window of infectivity for mutans streptococci between the ages of 19 and 31 months, when many children acquire mutans streptococci transmitted from their mothers. Part of the children that escape this window acquire mutans streptococci at a later age. In this group, maternal transmission is expected to be less prevalent. The present study compared the bacteriocin activity profiles of mutans streptococci isolated from mothers, fathers and children when the children acquired the mutans streptococci between the ages of 5 and 11. Twelve families were randomly selected from a group of 11–year–old children who were known to have acquired mutans streptococci during this age period. From the saliva of the mothers (n = 12), fathers (n = 8) and children (n = 12) approximately 30 mutans streptococci strains were isolated. All isolates were tested twice for bacteriocin activity against 21 indicator strains with a double–layer technique. Bacteriocin activity of strains was considered to be different when the number of strains against which bacteriocin was produced differed >1 or when the width of one or more inhibition zones differed ≥4 mm. In 7/12 mother–child pairs similar profiles were found. In the 8 father–child pairs similar profiles were only found on 2 occasions. In these 2 families, all 3 ( mother, father and child) harboured strains with a similar profile. In 4/8 father–mother pairs similar profiles were found. There was no correlation between the prevalence of mutans streptococci strains, the number of indicator strains against which the strains made bacteriocin, nor the mean size of the inhibition zones and the presence of similarity of bacteriocin activity profiles of mutans streptococci within the family members. The results show that even when a child acquires mutans streptococci after the age of 5, there may be similarity between mutans streptococci in mother, father and child, indicating that transmission between the family members occurs.
Changes in the Cultivable Flora in Deep Carious Lesions following a Stepwise Excavation Procedure
Authors: Bjørndal L. , Larsen T.
Published: April 2003

This study examined the cultivable microflora before and after stepwise excavation procedures in deep carious lesions in 9 permanent teeth, categorized according to degrees of proximal surface destruction. The final excavation was performed 4–6 months after the initial treatment, which included peripheral dentine excavation and removal of the central cariogenic biomass and the superficial necrotic dentine. Dentine colour and consistency were assessed by means of standardized scales before the application of a Ca(OH)2 compound and temporary sealing. Reassessments were performed before and after the final excavation. Microbiological samples of the central demineralized dentine were obtained with a sterile bur before and after the first excavation, as well as before and after the final excavation. After anaerobic cultivation on enriched non–selective tryptic soy agar, 30 colonies from a representative area were identified by standardized biochemical and physiological tests. Before temporary restoration, a yellowish and light brown demineralized soft dentine was typically observed, and gram–positive rods accounted for 70% and lactobacilli for 50% of the total colony–forming units. Lactobacillus casei subsp. rhamnosus and Actinomyces naeslundii dominated the lactobacilli and the other gram–positive rods, respectively. Gram–negative rods were the next most frequent isolates, followed by streptococci, each group accounting for about 20% of the colony–forming units in positive samples. Before the final excavation, which did not cause exposure of the pulp in any of the cases, the retained demineralized dentine had changed into a darker and harder tissue, and the total colony–forming units, as well as the frequency and proportions of lactobacilli were substantially reduced. Gram–negative rods also declined, and the flora was dominated by A. naeslundii and various streptococci. In conclusion, the cultivable flora detected following the treatment interval had declined substantially, and the distribution of bacterial species did not represent a typical cariogenic microbiota of deep lesions, confirming the clinical findings of arrested caries progression.