摘要:

A total of 1005 subgingival and extracrevicular samples from 201 male recruits, 18–25 yr old, were selectively cultivated forActinobacillus actinomycetemcomitans. The organism was isolated in 55 subjects (27%); 9.5% of pooled subgingival plaque samples from first molars, 14% cheek mucosa, 20% dorsum of tongue and 20% saliva samples were culture‐positive. In order to divide the study population into distinct clinical categories, cluster analysis was performed, based on previous caries experience, probing pocket depth categories, bleeding scores, visible plaque and calculus. Two clusters (n=86 and n=92, respectively) were identified with no or minimal periodontal disease (mean±standard deviation % of periodontal probing depth 1–2 mm 78.7±10.4% and 57.4±12.6%, respectively; virtually no periodontal probing/depth in excess of 4 mm) and a relatively low DMF‐S (22±13). A third cluster (n=22) had, in contrast, a high DMF‐S (47.7±173) and a relatively high % of periodontal pockets of ≥5 mm (5.9 ±5.2%). Prevalence ofA. actinomycetemcomitansin this cluster was 41%, while the organism was found in 23% and 27% in the minimally diseased populations (p<0.15). Whereas no heterogeneity of associations between subgingival and extracrevicular occurrence of the organism could be ascertained in different clusters, the organism was significantly more often identified in extracrevicular material, especially dorsum of tongue samples, compared with subgingival plaque (McNemar's X2=12.45, p<0.001). Multiple linear regression analysis revealed the number ofA. actino‐mycetemcomitanspositive samples as well as the % of sites bleeding on probing being positively associated with the % of sites with a probing pocket depth of ≥5 mm (R2=0.345, p≤0.0001). The present large‐scale investigation points to the wide distribution of this putative periodontopathogen in young individuals with mi

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00506.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

This study aims to determine whether gingival crevicular fluid (GCF) cathepsin B levels, total activity (TA) and concentration (EC) predict progressive attachment loss (AL). Seventy‐five previously untreated patients with moderate periodontitis were recruited. GCF was collected from 16 molar and premolar mesiobuccal sites and probing attachment level (PAL) and probing depth (PPD) were measured with an electronic probe. Gingival, gingival bleeding and plaque indices were then scored. Prior to baseline patients were given basic periodontal treatment after which the above procedures were repeated. Carefully localized radiographs were taken of the test teeth and repeated annually. Patients were seen 3‐monthly for 2 yr and the procedures were repeated. One hundred and twenty‐one AL sites, 90 rapid AL (RAL) and 31 gradual AL (GAL), in 49 patients were detected. Cathepsin B levels (TA&EC) at RAL sites were significantly higher (p<0.0001) than paired control sites at the attachment loss time (ALT) and prediction time (PT). Mean levels (TA&EC) over the study period at GAL sites were significantly higher (p<0.0001) than paired control sites. Using a critical value (CV) of 7.5 μU/30 s (TA) and 30 μU /μL (EC) showed a sensitivity of 100% and specificity of 99.83% (TA) and 100% and 99.75%(EC) at both ALT&PT. Mean cathepsin B levels (TA&EC) were significantly higher (p<0.0001) at RAL and GAL sites than nonattachment loss (NAL) sites in AL patients in intrapatient comparisons and mean patient levels were significantly higher (p<0.0001) in AL patients than NAL patients in interpatient comparisons. These results indicate that GCF cathepsin B may serve as a predictor of attachm

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00507.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Pro‐inflammatory cytokines such as interleukin (IL)‐1, IL‐6, TL‐8 and tumour necrosis factor (TNF) are believed to be the major pathological mediators of inflammatory diseases ranging from arthritis to the periodontal diseases. The stimuli inducing proinflammatory cytokine induction in the former disease is unclear but in the periodontal diseases it is obvious that the stimulus is the accumulation of bacteria in the subgingival region. As these bacteria do not invade the lesional tissues in large numbers, it is believed that their soluble components or products interact with host tissues to induce cytokine gene transcription. The paradigm is that lipopolysaccharide is the key bacterial component inducing pro‐inflammatory cytokine gene expression. However, over the past decade a growing number of reports on non‐oral bacteria have established that many other bacterial components, as well as secretory products, have the capacity to induce cytokine synthesis. Some of these, such as the proteinpneumolysinfromStreptococcus pneumoniae, are incredibly potent (in this case inducing cytokine synthesis at femtomolar concentrations). This review surveys the range of bacterial components and products which have been shown to stimulate cytokine synthesis with particular emphasis on the hypothesis that these components play a role in the pathology of the periodont

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00508.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Inhibitory effects of a rhubarb (Rhei rhizoma) solution and its fractions on the formation of calcium phosphate precipitates were studied. The rhubarb solution inhibited both the amorphous calcium phosphate (ACP) formation and the rate of hydroxyapatite (HAP) transformation, and extended the induction time. When the solution was fractionated using membrane filters, a filtrate with the molecular weight between 3 and 10 kDa (with 2/3 recovery of polyphenols) was found to be responsible for both the ACP formation and the extension of the induction time. Another filtrate with the molecular weight below 3 kDa (with 1/3 recovery of polyphenols) may be responsible for the inhibition of both the ACP formation and the rate of HAP transformation, and the extension of the induction time. When the extract of rhubarb was fractionated using a Sephadex LH‐20 column chromatography, fraction IV greatly inhibited the formation of calcium phosphate precipitates, while fractions I, II, and III slightly inhibited that reaction. Our finding suggests that fraction IV may contain useful substance(s) for the prevention of oral calcium phosphate precipitation (calculus formation). However, strong calcium chelating properties would limit the concentration that could be safely employe

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00509.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Using the method of reconstitution of nude mice with T cells, we examined the effects of T cell on alveolar bone resorption induced by repeated injections ofEscherichia coliendotoxin into periodontal tissue. Three mice groups (normal, nude and T cell reconstituted nude mice) were used. Endotoxin derived from E. coli was repeatedly injected into the gingiva of the mice left mandibles every 48 h and the mice were killed on the day after the 1st, 4th, 7th, 10th, 13th and 20th injections of endotoxin. Alveolar bone resorption was examined histopathologically and histomorphometrically. Bone surfaces in contact with the osteoclast were defined as the site of active resorption and the ratios of active resorption were compared among the 3 nice groups. Consequently, no active resorption was found after the first injection of endotoxin in any group. After the 4th injection, active resorption was found in normal nice and T cell reconstituted nude mice and gradually rose with the increase in the injection frequency. In contrast, few osteoclasts were found even after the 10th injection in the nude mice. In addition, there were statistically significant differences between the normal price and nude mice after the 4th and 10th injections (p<0.05). These findings suggested that T cell influences periodontal bone destruction induced by local administration of endotoxin during the early phases.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00510.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Black‐pigmented anaerobes have been implicated as major pathogens in the aetiology of adult periodontitis but these organisms are also found in healthy sites. This study aimed to examine the relationship between genotypes of black‐pigmented anaerobes and disease status of periodontal sites using restriction endonuclease analysis (REA) and ribotyping. The main black‐pigmented species recovered from sites were Potphyromonas gingivalis, Prevotella intermediaandPrevotella nigrescens. Each of the 58 subjects investigated harboured distinct genotypes of these three species. Most subjects appeared to be colonized by a single genotype ofP. gingivalisandPr. intermedia. whereas multiple types ofPr. nigrescenscolonized many individuals. Plasmids were only found in a fewPr. nigrescensstrains. No association was found between the disease status of sites and any specific or group of genotypes of either species or presence of a plasmid. Since the same genotypes ofP. gingivalis, Pr. intermediaandPr. nigrescenswere found at both diseased and non‐diseased sites in a subject, adult periodontitis is not explained by the presence of specially virulent clones of these organisms. Their role in periodontitis, therefore, is likely to be opport

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00511.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

The purpose of this study was to investigate the distribution of epithelial cells and the fate of the basement membrane along the root surface of rat molars during cementogenesis, and to test the hypothesis that the Hertwig's epithelial root sheath (HERS) cells remain on the root surface if mineralization is inhibited. To demonstrate the HERS cells and basement membrane, immunohistochemistry with antibodies against keratin and laminin were used. The dentin matrix mineralization was inhibited by a single injection of 1‐hydroxyethylidene‐1,1‐bisphosphonate (HEBP). A modified Gomori staining method was used to monitor the inhibition of mineral formation in dentin and cementum. Paraffin sections were stained with haematoxylin‐eosin. and freeze‐dried sections were used for Gomori and immunohistochemical stainings. We found that the formation of acellular cementum was suppressed above the dentin with inhibited mineralization. Instead, a hyperplastic matrix, different from acellular cementum, covered the dentin. This hyperplastic cementum had keratin‐ and laminin‐positive cells incorporated; such cells were never incorporated in normal acellular cementum. The later formation of cellular cementum correlated, in controls, with the disappearance of HERS cells from the root surface. Treatment with HEBP resulted in a persistent presence of epithelial cells, interpreted as an inhibition of their disappearance. In conclusion, there is evidence that the cells of HERS are involved in the development of both acellular and cellular cementum. The developmental processes of these tissues appear in some way to be influenced by or associated with the initial mineralization

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00512.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00513.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1996.tb00514.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY