摘要:

Ligature‐induced periodontitis was evaluated microbiologically in 8 beagle dogs. Gingival health was established by repeated cleaning. At day 0 subgingival plaque was sampled from individual sites in two quadrants. All teeth in one quadrant were then ligated at the CEJ, and the other quadrant served as a non‐ligated control which was cleaned three times each week. At day 14, four dogs were given metronidazole for seven days. Plaque was cultured anaerobically on nonselcctive media, and the predominant cultivable flora was characterized. At day 0 Gram‐negative facultative rods represented 56.8 % of the flora. with motile and surface translocating organisms predominating. At day 14Bacteroides asaccharolyticus, including catalase positiveB.asaccharolyticus‐likeorganisms, increased at ligated sites to 34.7 % of the cultivable flora. After metronidazole therapy the total bacterial count decreased, and Gram‐negative anaerobic rods became non‐detectable. Gram negative facultative bacteria which were motile or surface translocating represented 52.7 % of the cultivable flora after metronidazole treatment.In the beagle dog ligature placement was associated with a shift in the flora from Gram‐negative facultative rods to Gram‐negative anaerobic rods. Metronidazole treatment reduced the total cultivable flora and selectively reversed the microflora shifts which followed lig

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00973.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The microbial flora of healthy gingival crevices and of periodontal pockets was studied to determine if a relation exists between the presence ofBacteroides asaccharolyticusand/or saccharolytic subspecies ofB. melaninogenicusand the severity of the disease. Seventy‐eight samples were collected with sterile absorbent points from 40 individuals. The samples were immediately placed in reduced transport fluid. After dispersal by sonic treatment, the samples were put into an anaerobic chamber, serially diluted and plated on modified MM10 medium. After incubation, plates were examined and major bacterial types were counted. Black‐pigmented colonies were selected for further characterization. Samples from patients with severe inflammation (gingival index, GI = 3) showed a greater proportion of Gram‐negative anaerobic rods and 31.8 % of these organisms were identified asB. asaccharolyticus.This organism was absent in healthy sulci. It was recovered from mildly inflamed sites (GI = 1 or 2) but less often thanB. melaninogenicusssintermedius. B. melaninogenicusssmelaninogenicuswas found only occasionally and in low nu

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00974.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Demineralization of teeth with their adherent bacterial flora is a prerequisite for the localization of selected species in sections of undisturbed bacterial deposits by immunoelectron microscopy. The effect of EDTA dernineralization on the immunological labeling of Gram‐positive and Gram‐negative oral bacteria was tested on strains ofActinomycesviscosus, A. israelii, Eikertella corrodens, Bacieroides meloninogenicus. Capnocytophaga sputigenaandWolinella recta. After 3 months in EDTA, cells prefixed in paraformaldehyde‐picric acid were washed and incubated with homologous rabbit antiscrum followed by goat anti‐rabbit IgG to enhance the immunocoating reaction. Samples were then processed for transmission electron microscopy. Control specimens included (1) demineralized cells incubated with pre‐immune rabbit sera instead of homologous antisera (2) cells stored for 3 months in PBS instead of EDTA (3) fresh cells processed for immunocoating immediately after prefixation and washing. No detectable immunocoating layer was found on the cells of the control group incubated with pre‐immune rabbitserum, EDTA treated cells demonstrated an immunocoating layer of similar density and thickness to that of cells stored in PBS, or fresh cells. The results indicate that immunoelectron microscopic localization of bacterial cells may be feasible in ullrathin sections of demineralized denta

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00975.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Several morphometric and cellular parameters were studied in the rice rat (Oryzomys palustris). When fed a soft, high carbohydrate diet, a severe periodontal disease occurred, with significant alterations in the morphometric and cellular endpoints observed. Weaned animals were placed on a high carbohydrate diet for periods of 6, 12 or 18 weeks. There was a linear, rapid loss of bone by 18 weeks, approaching a 75 % loss of original bone. Vascular spaces decreased as the remaining connective tissue became fibrotic in character. The percentage of the interdental test site which was destroyed by periodontal disease increased dramatically over the time of the experiment. The numbers of fibroblasts per mm of bone surface increased slightly at the 18 week period; osteoblasts were unchanged at any period. The numbers of osteoclast nuclei rose dramatically by 12 weeks, and these cell nuclei remained at increased levels at 18 weeks. Also, the numbers of inflammatory cells residing at the bone surface increased greatly by 18 weeks time. Finally, the numbers of3H‐TdR labeled periodontal ligament (PDL) fibroblasts increased significantly at both 12 and 18 weeks time. These cellular changes and their relation to the bone loss due to periodontal disease are discusse

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00976.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Immunoreactive collagenase was detected in four of eight specimens of diseased gingival tissue when sampled prior to treatment. Specimens taken From patients who had previously received initial therapy and whose tissues showed no clinical signs of inflammation, showed insignificant immunoreactive collagenase. All specimens were frozen within minutes of surgery. The enzyme was associated with connective tissue adjacent to the pocket epithelium and at the advancing front of the lesion. No enzyme was observed in association with intact gingival epithelium, Immunoreactive enzyme was frequently associated with inflammatory cells but the precise cellular origin of collagenase remains uncertain. These findings demonstrate the presence of tissue collagenase at sites of active collagen resorption thereby suggesting a degradative role for this enzyme in periodontal disease.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00977.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00978.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The effect of cell cycle stages on collagen and protein synthesis by human gingival fibroblasts was investigated. The fibroblasts were synchronized by depriving them of serum for 48 hours and then activating them to divide by adding 10 per cent fetal calf serum. At various time points, the cells were pulse labeled with radioactive proline, and protein and collagen synthesis were measured. Proteins were quantitated by total proline incorporation and collagen was assayed by digesting it with purified bacterial collagenase. Protein synthesis increased with time and reached maximal levels at and after 24 hours, the time of peak DNA synthesis. The proportion of collagen synthesized also increased, and it reached maximum values after 33 hours. The levels of transport of proline into the cell did not parallel the protein synthesis. Confluent and nonconfluem cells gave similar results. The ratio of collagen type I to type III collagen did not significantly vary at any time and no new collagens were detected.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00979.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

An electron microscopic survey and stereological analysis were made of the lamina propria of human gingival tissues from 8 patients with periodontitis and 6 patients clinically free of pathology (normal). The connective tissue was classified and divided into Zones A, B, and C, according to their collagen content, fibroblastic status (active or inactive), and numbers of inflammatory cells. Fibroblastic phagocytosis of collagen was most prominent in relatively stable areas (Zone A) where the collagen content was high, fibroblasts were classified as inactive (resting), and there were no inflammatory cells. Active (synthesizing) fibroblasts were conspicuous in Zone B, where intercollagenous spaces were wide and mononuclear cells occurred. Phagocytosis of collagen in the human gingiva was found to be a minor function of fibroblasts in Zone B and the highly inflamed Zone C.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00980.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Direct cytotoxicity of plaque is believed to play a role in the soft tissue destruction observed in periodontal disease. This property has been demonstrated in vitro on cell lines but appears to be dependent upon the target cell used and the plaque organism being tested. The purpose of this investigation was to determine the effects of bacterial products on growth of keratinized stratified squamous epithelium maintained in vitro. Morphological features of these cultures closely resembled normal epidermis. Sterile sonicates of the periodontal pathogenesBacieroides asaccharolyticusandActinomyces, naeslundiiwere diluted to equal protein concentrations and added lo keratinocyte cultures. TheBacteroidessonicate caused up to 97 % inhibition of labelled thymidine uptake of cultured keratinocytes while the peak inhibition of theActinomycessonicate was only 39 % of untreated controls. These results indicate that products ofB.asaccharolyticuswere more inhibitory to the growth of cultured keratinocytes than products ofA. naes lundii.and that keratinocyte cultures make a useful model for investigation of the interactions between periodontal pathogens and differentiating epidermal cells.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00981.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Specimens of both human and animal gingivae were examined by fibrinolytic autography and all showed lysis over the gingival pocket epithelium, lysis never occurring over oral gingival epithelium. Epithelium separated from the connective tissue also showed fibrinolytic activity confined to the pocket epithelium. Examination of human gingival crevice washings showed fibrinolysis over some nucleated squamous epithelial cells as well as over anuclcated cell fragments. Although ihe neutrophil leucocytes in crevicular washings have fibrinolytic activity, this activity does not compare with that of the epithelium. The fibrinolytic activity of gingival pocket epithelium may be important in the pathogenesis of gingivitis and periodontitis, particularly due to the ability of plasmin lo activate complement.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb00982.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY