摘要:

Abstract –Bovine tooth germs dissected from the mandible immediately after bleeding of the less than 1‐yr‐old calves(Bos taureus)were used to study the initial phases of giant tubule (GT) formation. Three stages could be discerned. Firstly, the initial manifestations were represented by loci about 150 μm apart in the axiomesiodistal plane along the pulpal border of the I00–200‐μm‐thick incisal dentin. Some of these loci showed only a blunt capillary loop and associated cells, whereas in most others there was a 50–100‐μm‐wide dense matrix consisting of coarse collagen fibrils and showing a metachromatic staining reaction to toluidine blue. Fibroblasts lined this matrix, and a capillary loop was always present underneath. Both kinds of GT origins were eventually circumvented by the odontoblasts situated incisal to them. The matrices became enclosed in the dentin. In the second stage, the GT grew in length as new dentin was formed. In this stage the vascular loops and the adjoining fibroblasts remained stationary within the GT lumina relative to the origins. In the third stage the GT vessels started to migrate pulpally relative to the origins. This seemed to be the result of a sequestration of the most incisal portions of the vascular loops. In this last stage the formation of collagen fibrils in the GT lumen incisal to the

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01587.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –A material of bovine, red deer, and rat incisors was investigated, with emphasis on the bovine teeth. Both ground sections and paraffin wax sections of demineralized material were used. The sections were investigated by ordinary and polarized light microscopy and contact microradiography. In the bulk of the dentin irregular column‐like light structures, alternating with largely similar, but dark, columns, followed the course of the dentinal tubules from the pulpal border to just below the mantle dentin. Each column, 10–100 μm in diameter, contained a highly varying number of tubules. The difference between light and dark columns was mainly related to the intertubular dentin of the globules of which they were composed. Light columns were slightly more mineralized than the dark ones and seemed to contain fewer GAGs, but more glycoproteins. A difference in fiber direction between light and dark columns was also evident. To the authors' knowledge these structures have not attracted the attention of previous w

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01588.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –Salivary and microbial conditions were examined in 124 50–60‐yr‐old patients attending a dental clinic of the Public Dental Health Service. They were then randomly divided into a control and a test group. Patients with low salivary secretion rate and buffer capacity and high numbers of mutans streptococci and lactobacilli in the test group received special caries preventive measures during 1 yr. In the control group all patients were given prevention according to routine procedures. The incidence of dental caries between the groups was compared. The risk patients in the control group developed 1.67 new carious lesions as compared to 0.19 in the test group. The difference was statistically significant (P<0.05). Also the numbers of mutans streptococci and lactobacilli were significantly lower in the risk patients in the test group after 1 yr compared with baseline values. After the experimental year all patients were treated according to routine procedures. Five years after the start of the study a new examination showed increased caries activity in the risk patients in the test group and the gain which had been made during the experimental year was almo

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01589.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –The clinical manifestations of amelogenesis imperfecta (AI) were described in 165 individuals from 51 families. The inheritance pattern for AI in these families had previously been investigated, and it was hypothesized that AI probably is solely an autosomal dominant (AD) or X‐linked trait. To test this hypothesis the connection between clinical manifestation and inheritance pattern was studied. Eight different variants of AI were seen. In 33/51 families all affected individuals could be assigned to the same clinical variant. In 8/51 families those affected were assigned to different clinical variants. In the two families where an X‐linked recessive (XR) inheritance pattern was found probable, the clinical manifestation differed between women and men. Except for one variant only seen as an AD trait, and the manifestation in women in families with an X‐linked recessive inheritance pattern, no connection was found between a specific inheritance pattern and a specific clinical manifestation. Accordingly it seems likely that AI is solely an AD or X‐linked trait. The different clinical variants observed should be regarded as a varying expressivity of the gene and in the families with X‐linked inheritance probably due to lyonization. In the remaining families the modifying mechanisms ar

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01590.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –This study showed that pyrophosphate (PP) desorbed an acidic protein (albumin) from hydroxyapatite (HA) more effectively than phosphate and that HA pretreated with PP took up markedly less protein than untreated HA. The protein which adsorbed to PP‐treated HA was more loosely bound than that adsorbed to untreated HA. In vivo experiments showed that pellicle formed more slowly on PP‐treated etched enamel than on untreated controls. The possible clinical implications of these findings are disc

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01591.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –Fluoride acquisition during topical fluoride treatment was studied after different time intervals, at different concentrations and at different pH. The effects of pretreating the enamel with Ca++, and of pre‐etching were also tested. Four experimental groups of repeated measures design were established. Chemical assessments were made of the amounts of fluoride formedon(as alkali soluble fluoride, i.e., calcium fluoride) andinenamel (as firmly bound fluoride). The depositionsonenamel were also demonstrated by SEM. The amounts of alkali soluble fluoride on enamel increased with time, concentration, pH‐decrease and calcium availability. The time of exposure seemed to be the major factor. The amounts of fluoride depositedonenamel outranged by far (>70%) the amounts of fluoride acquiredinthe enamel. The formation of alkali soluble fluorideonenamel is probably limited by the availability of calcium ions. It is suggested that the fluorideonenamel may protect the enamel surface and serve as a reservoir of flu

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01592.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –As part of an evaluation of the potential of topical application of TiF4in the prevention or arrest of root caries, the longevity of the titanium‐rich glaze and the long‐term retention of titanium and fluoride in exposed dentin surfaces were examined in dogs. For comparison, the effect of fluoride in combination with another cation, tin, was studied as well. Facets of exposed dentin were prepared in two beagles and treated for 1 or 4 min with either a TiF4or an SnF2solution (1.1 M F, native pH). After 3, 7, or 21 wk, the experimental surfaces were analyzed for fluoride, titanium, tin, and calcium using an electron microprobe. Dentin surfaces treated with TiF4for 1 min showed fluoride concentrations ranging from less than 0.15% to 1.03%, while those treated for 4 min with SnF2showed values from 0.22% to 1.28%. The calcium analyses revealed partial surface demineralization in one half of the SnF2‐treated specimens, while this was a rare finding in the TiF4group. The findings show that a brief application of TiF4to exposed dentin results in approximately the same increase in fluoride content as a 4‐min application of SnF2, with, however, less surface demineralization. In addition, the presence of a surface glaze may impart an added benefit to the use of TiF4as a topical agent in the prevention of ro

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01593.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –Zinc ions and chlorhexidine (CH) were found to exhibit a synergistic inhibitory effect on in vitro growth ofS. sobrinusOMZ 176 and ofS. sanguis10556. A clinical mouthrinsing experiment was performed in a group of 10 volunteers to assess the plaque‐inhibiting capacity of this combination. Sucrose enhanced plaque accumulations were assessed (Plaque Index, Silness&Löe) after 4 days of twice daily mouthrinses with 10 ml aqueous solutions of either 10.0 mM zinc or 0.55 mM CH, or with a combination of zinc ions and CH, during which period no mechanical toothcleaning was performed. The Zn–CH combination showed improved inhibition properties compared to the individual agents. The effects on plaque acidogenicity of 8.0 mM zinc, 0.44 mM CH, and of zinc and CH in combination were also assessed in a test panel of five volunteers. The Zn–CH combination inhibited acid production by dental plaque significantly (P<0.05) more than the individual agents 1 h 30 min after a sing

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01594.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –The aims of the present investigation were, first, to follow the secretion of free glucose in parotid saliva in various subjects after a single oral intake of different carbohydrates, and second, to compare the salivary glucose concentration with the concentration in blood. Twenty healthy subjects, three women and 17 men, 20–35 yr of age, participated. They were asked not to eat or drink anything from 10 p.m. the night before the examination. 75 g of carbohydrate (glucose, fructose, or sucrose) dissolved in 300 ml water was ingested the next morning at 8 a.m. One experimental series with glucose was performed in triplicate in 10 of the subjects. Approximately 1.5 ml of citric acid‐stimulated parotid saliva was collected before (0 min) and 15, 30, 45, 60, and 120 min after the intake. Salivary concentration of glucose was analyzed enzymatically. Most of the 0‐min samples showed a variation in glucose concentration from 5 to 25 μmol/l. After the glucose, fructose, and sucrose intakes, the salivary glucose level increased about 2–4 times, especially in the 30‐min samples. A large inter‐ as well as intra‐individual variation was found both in the 0‐min samples and in the samples collected after the different intakes. The correlation between the glucose concentration in saliva and blood was higher after than before the ca

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01595.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

Abstract –The aim of this study was to elucidate whether soft tissue reactions during chlorhexidine (CHX) treatment might be associated with meticulous oral hygiene measures. A commercially available 1% chlorhexidine digluconate gel (Hibitane Dental Gel) was applied in a custom tray for the mandibular arch, 10 min daily, for 14 days. A split mouth approach was used to allow evaluation of the effect of oral hygiene measures with toothbrush, toothpaste, and dental floss on one side of the arch. During the treatment period, 8 out of 12 subjects developed gingival and/or mucosal reactions appearing as white patches or ulcerations. Both the gingival reactions on the buccal marginal gingiva and the mucosal reactions near the margin of the custom tray occurred only when the gel treatment was combined with meticulous oral hygiene measures. The white patches, which could easily be detached, leaving ulcerated areas, consisted entirely of stratified squamous epithelium. The findings suggest that intensive treatment with chlorhexidine gel, in individually fitted custom trays, combined with meticulous oral hygiene measures may induce toxic effects on the surface layers of the gingiva and mucos

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1988.tb01596.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY