Prevalence of dental caries in schoolchildren in Italy

The glycosylation of serum transferrin from galactosemic patients with a deficiency of galactose-1-phosphate uridyl transferase (EC 2. 7.7 12) is abnormal but becomes normal after treatment with a galactose-free diet. To understand the structural and biochemical basis of the abnormal glycosylation, transferrin was purified from the serum of untreated and treated galactosemic patients and normal controls and the N-linked glycans analyzed by HPLC. The glycans from normal transferrin consisted predominantly (86%) of the disialylated biantennary complex type. The glycans from untreated galactosemic patients were more heterogeneous and contained four major truncated glycans in addition to a smaller amount (13%) of the disialylated biantennary complex type. The truncated glycans were deficient in galactose and sialic acid and their structures were consistent with a decrease in galactosyltransferase activity in hepatocytes, the probable cells of origin of the transferrin. This is postulated to be due to direct inhibition of the galactosyltransferase activity by the accumulated galactose-1-phosphate or to an effect on the formation of UDP-galactose, the donor substrate in the reaction. After treatment the proportion of the truncated glycans decreased and the proportion of the disialylated biantennary complex type increased, returning almost but never completely to normal, even after prolonged treatment in some cases. There was no clear relationship between the length of treatment and the normalization of glycosylation and the level of galactose-1-phosphate in red blood cells, the usual parameter for monitoring the treatment of galactosemics. It is suggested that the persistence of abnormally glycosylated proteins may contribute to the long-term complications in galactosemia.     

Laser-induced autofluorescence spectroscopy of dental caries

The Menkes protein (MNK or ATP7A) is an important component of the mammalian copper transport pathway and is defective in Menkes disease, a fatal X-linked disorder of copper transport. To study the structure and function of this protein and to elucidate its role in cellular copper homeostasis, a cDNA construct encoding the full-length MNK protein was cloned into a mammalian expression vector under the control of the CMV promoter. Transfection of this plasmid construct into CHO-K1 cells yielded clones that expressed MNK at varying levels. Detailed characterization of four clones showed that an increase in MNK protein expression led to a corresponding increase in the level of copper resistance of the cells. Subcellular localization studies showed that in the parental CHO-K1 and the transfected cell lines, MNK was located in a post-Golgi compartment which, based on immunogold electron microscopic analyses, most likely represented the trans -Golgi network (TGN). When the extracellular copper concentration was increased, MNK in the clones as well as in CHO-K1 cells was redistributed to the cytoplasm and plasma membrane, but returned to the TGN under basal, low copper conditions. This report presents the first ultrastructural evidence for the association of MNK with vesicles within the cell and with the TGN and plasma membrane. It also demonstrates the stable expression of a functional MNK protein from a cDNA construct in mammalian cells, as well as the copper-induced redistribution of MNK in a cell line (CHO-K1) that was not selected for copper resistance or overexpression of MNK.     

Treating dental caries as an infectious disease. Applying the medical model in practice to prevent dental caries

The article stresses that railway hygiene has accumulated vast experience in evaluation of working environment of railway construction workers in severe climate conditions, thorough hygienic characteristics cover the main construction occupations and the exploitation staffers. The research helped to elaborate variety of hygienic regulations on occupational hygiene and work schedules for railway construction workers, on hygienic basis of the workers' everyday life in severe climate conditions.     

Oral hygiene in relation to caries development and immigrant status in infants and toddlers

The purpose of this study was to describe oral hygiene factors in infants and toddlers living in Sweden with special reference to caries prevalence at 2 and 3 yr of age and to immigrant status. The study was designed as a prospective, longitudinal study starting with 671 children aged 1 yr. At 3 yr, all the children were invited to a further examination. A total of 298 children, randomly selected from the original group, were also examined at 2 yr. The accompanying parent was interviewed about the child's oral health habits. Children who were free of caries at 3 yr had had their teeth brushed more frequently at 1 and 2 yr of age, had used fluoride (F)-toothpaste more often at 2 yr of age, and had a lower prevalence of visible plaque at 1 and 2 yr of age than children with caries. Immigrant children had had their teeth brushed less frequently, had used less F-toothpaste, and had a higher prevalence of visible plaque at 1 yr of age than nonimmigrant children. Early establishment of good oral hygiene habits and regular use of F-toothpaste seem to be important for achieving good oral health in pre-schoolchildren.     

Declining prevalence of dental caries in school children in Singapore

Slime layers and capsules are common amongst medically relevant bacteria. We herein report that Treponema denticola, which has been associated with periodontitis, synthesizes or acquires an extracellular polysaccharide layer that we have observed through electron microscopy using the polysaccharide-specific dye Alcian blue and phosphotungstate. We have also visualized this extracellular layer by dark-field microscopy of Alcian blue-stained spirochete cells. A representative strain of each of the oral spirochete species T. denticola, Treponema vincentii and Treponema socranskii were differentiated by concanavalin A, phaseolus, lotus A and arachis lectins in a microtiter plate immunoassay for the detection of surface sugars.     

Clinical evaluation of sodium fluoride chewable tablets in dental caries

Chewable tablets containing low dosage fluoride content were prepared using two varieties of celluloses and their in vitro parameters were evaluated. An eighteen month clinical trial revealed that both these formulations were effective in controlling the caries. However, ethyl cellulose is proved to be superior to methylcellulose as a controlled release matrix material in controlling caries. Thus this study recommends ethylcellulose matrix tablets containing low fluoride content is an efficacious and cost effective drug device in controlling dental caries.     

Clinical and historical predictors of dental caries on radiographs

Jet injection can be used to introduce genes into the cells of differentiated tissues of living animals and organ cultures. When a solution of plasmid DNA is jet injected into a selected tissue or organ, cells lying in or near the path of the jet injection are transfected with the DNA and the introduced gene(s) are expressed. Since there is minimal morbidity from each jet injection, multiple injections can be performed at the same or nearby sites. Both mRNA and protein expression from transfected genes can be quantitated using standard methods. In addition, the technique is an efficient means of DNA immunization. Methodology for using jet injection to transfer plasmid DNA into the cells of skin, fat, mammary gland, and muscle are described.     

Model investigations of caries inhibition by fluoride-releasing dental materials

Fluoride-releasing dental materials are generally believed to reduce or prevent secondary caries. The evidence for this is largely anecdotal and centers on clinical experience with silicate cements and, more recently, with glass-ionomer cements. Unfortunately, corroborating evidence from controlled clinical trials is inadequate to establish precisely how effective these materials are or under what conditions they might be effective. Even less is known about the clinical effectiveness of newer materials that, often, release less fluoride. In vitro model systems have been used to study the effects of dental materials on de/remineralization of surrounding tooth structure. Fluoride-releasing materials have been shown in these models to reduce demineralization of both enamel and dentin compared with a material that does not release fluoride. This is useful from a mechanistic standpoint, but without clinical "standards" to guide model results, it is not possible to define an acceptable level of fluoride release or the length of time such release is required. A limited number of in situ model studies has been conducted, and some fluoride dose-response information has been obtained. These models are closer to the real situation and perhaps provide the best means to define required levels of fluoride release from materials in the absence of adequate clinical information.     

Iontophoresis: an alternative in the treatment of dental caries?

Celiac sprue (CS) is frequently complicated by malignancy, most commonly small intestinal lymphoma. Our study was performed in an area with a high prevalence of CS to define the clinical features, response to treatment, and outcome of this tumor. Of a total of 31 lymphomas complicating CS identified, 30 case records and 24 tumor specimens were reviewed. Overall 1-year survival was 9 of 29 (31%) and 5-year survival 3 of 27 (11%). Seven previously diagnosed celiac patients developed lymphoma; length on gluten-free diet ranged from 12 to 252 months (median 44 months). In this group, presentation was nonspecific, diagnosis difficult, and survival poor (lymphoma diagnosed in life in four of seven, mean survival 2.25 months). Twenty-three patients had CS and lymphoma diagnosed during the same illness. In this group, 14 of 23 presented with a surgical emergency and were treated with tumor resection and chemotherapy. Nine are disease-free and alive or died of another cause after 10-196 months (mean 74 follow-up). Celiac-associated lymphoma is a frequent, difficult to diagnose, and commonly fatal complication of CS. An aggressive diagnostic approach, including laparoscopy, is recommended. Long-term survival can be expected in a significant number of these patients and in our series was almost exclusively confined to those treated with chemotherapy.     

A new correction procedure for calibrating dental caries frequency

The incisors and canines and the premolars and molars show differential resistance to cariogenic factors. The anterior teeth have a lower caries frequency than the posterior teeth. However, these tooth classes are lost differentially in postmortem stages due to their anatomical structures. This differential postmortem tooth loss distorts proportions between the anterior and posterior tooth classes. The disproportionality can affect the calculation of total caries prevalence. In this paper, we propose a new calibration procedure which removes this disproportionality and call it the proportional correction factor. For this procedure, the caries rates of anterior and posterior teeth are corrected by multiplying the anterior teeth by three-eighths and the posterior teeth by five-eighths. These fractions are derived from the human dental formula which contains three anterior and five posterior teeth by side. The correction factor is more effective if the proportion of anterior to the posterior teeth is extremely distorted. When this procedure is used with the caries correction factor, it provides a useful way to approach to an almost true caries prevalence.     

Epidemiological correlates of dental caries in an urban slum of West Bengal

The overall prevalence of dental caries was found to be 57.47 percent in an urban slum irrespective of sex, with a maximum of 75.88 percent in the age group of 5-9 years. Habit of taking hard and sticky food, bad oral hygiene were some of the important epidemiological correlates. Fluoride content of drinking water did not show any significant role.     

Evaluation of Guamanian dental caries preventive programs after 13 years

The authors followed the collection of 77 eyes with glaucoma (54 eyes with POAG, 16 eyes with PACG and 7 eyes with CG) after ECCE or phacoemulsification with implantation of IOL. The patients were operated in 1990-1991 at the Ophthalmological Clinic FNKV and 3rd Medical Faculty in Prague. The authors evaluated IOP, therapy and visual acuity 6 weeks and 6 months after operation. After 6 months period IOP was decreased in average about 3 mmHg; in POAG the reduction was 1.9 mmHg and in PACG the reduction was 4.7 mmHg. In this time the authors also registered decreasing antiglaucomatous therapy at 38 eyes (i.e. 49.3% operated eyes). The reducing therapy represents 50% eyes with POAG and 69% eyes with PACG. The visual acuity is in 70% 6/6-6/12. Patients with PACG have more expressive postoperative effect. The authors draw the attention to late diagnosis CG, after successful operation the visual acuity is reduced on account of advanced changes of the optic disc.     

Detecting approximal dental caries with transillumination: a clinical evaluation

Independent examinations of 300 patients were conducted to evaluate fiber optic transillumination's performance in caries detection. FOTI was used as an adjunct to clinical and radiographic examinations for caries, restoration or secondary caries of approximal surfaces in maxillary anterior permanent teeth. Clinical and radiographic examinations were significantly more effective.     

Changes in dental caries prevalence of school children in Araraquara, SP, Brazil

Previous reports indicate that venous thrombosis is an infrequent problem in patients with HIV infection. Despite this, various HIV-related factors have been proposed as potentially thrombogenic and an HIV-related hypercoagulability has been suggested. At the present time, there exists no consensus of opinion regarding prophylaxis against venous thrombosis for hospitalized patients with HIV. This article aims to provide an overview of venous thrombosis in HIV infection with particular reference to published and personal evidence for possible risk factors and their implications for prophylaxis.     

Prevalence of developmental enamel defects and dental caries in rural pre-school Thai children

The prevalence of developmental enamel defects and dental caries was assessed in 344 Karen children aged 1-4 years who were chronically (70 per cent) and acutely malnourished (9.3 per cent) The teeth were cleaned with gauze to facilitate detection of hypoplastic lesions on labial surfaces of maxillary incisors. At least one tooth with defective enamel was seen in 31.9 per cent of children, while enamel hypoplasia was present in 22.7 per cent of children. Enamel defects were found in 21.2 per cent of teeth, with hypoplasia and opacities occurring in 14.6 and 6.6 per cent of teeth, respectively. Gender did not alter the prevalence of defects. The upper central incisors were affected more than lateral incisors. The prevalence of dental caries was 31.9 per cent with a mean dt of 1.1. The prevalence of caries associated with enamel hypoplasia was significantly greater than that associated with opacities and sound enamel (P < 0.0005).