摘要:

The principal fibers and cellular cementum were examined in various developmental stages in rat molars by light and electron microscopy, and their development and structure were studied. The principal fibers increased in thickness with root development. At any given stage, the principal fibers consisted of small fiber bundles on the cementum surface and showed a branching structure. Sharpey's fibers also showed a similar branching structure and increased in thickness, as traced superficially in the cementum. It was suggested that the principal fibers increased in thickness by means of the aggregation of fiber bundles. The development of cellular cementum was divided into two (early and late) phases on the basis of the fiber arrangement. The early cementum was believed to contain a few Sharpey's fibers and many randomly arranged intrinsic fibers. The late cementum contained thicker Sharpey's fibers with branches and the intrinsic fibers which appeared to encircle Sharpey's fibers and/or meander among them.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01636.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The ultrastructural localization of collagens type V and VI in normal human gingival mucosa was investigated by immunoelectron microscopy. Twenty biopsies were fixed in dimethylsuberimidate and shock‐frozen in slush nitrogen. Collagen type V was mainly located to meshworks of uniform nonstriated microfibrils of 12 to 20 nm width, which preferentially appeared in larger spaces between cross‐striated major collagen fibrils. Occasionally single microfibrils of collagen type V fanned out from the ends of major collagen fibrils, which may indicate a role as a core fibril. Collagen type V was not found in the subepithelial basement membrane and the immediately adjacent stroma. Collagen type VI was detected in a loose reticular network of unhanded microfilaments that were morphologically distinguishable by knoblike protrusions every 100–110 nm. These microfilaments were found in the vicinity, but not as an intrinsic component, of the subepithelial basement membrane. Single filaments of collagen type VI filaments appeared to form bridges between neighboring cross‐striated major collagen fibrils, suggesting an interconnecting role for this collagen type. The method presented appears to be excellently suited to study the normal and pathological supramolecular organization of the oral extracellular

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01637.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Fibroblasts are the principal cell type in the soft connective tissues of the periodontium; they perform important functions in development, physiology, and disease. A growing number of reports have indicated site‐specific phenotypic variation of fibroblasts. Heterogeneity of metabolic traits has been demonstrated in cells from healthy and diseased tissues. The tissue distribution and relative proportions of fibroblast subpopulations have a significant impact on the regulation of connective tissue function in health and diseas

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01638.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Lipopolysaccharide (Y4 LPS) isolated fromActinobacillus actinomycetemcomitansstrain Y4 induced bone resorption in BALB/c mouse calvaria organ culture. The calcium release from LPS‐low responsive C3H/HeJ mouse calvaria by Y4 LPS was very low. Indomethacin almost completely inhibited prostaglandin E2(PGE2) production by Y4 LPS‐stimulated BALB/c mouse calvaria, but did not suppress interleukin‐1 (IL‐1) release from the calvaria, and partially suppressed the bone resorption. Dexamethasone strongly inhibited the PGE2and IL‐1 production by Y4 LPS‐stimulated BALB/c mouse calvaria. as well as Y4 LPS‐induced bone resorption. Dexamethasone inhibited expression of membrane IL‐1 on osteoblastic cells stimulated with Y4 LPS, but indomethacin did not. Furthermore, anti‐IL‐1 serum partially suppressed the calcium release from Y4 LPS‐stimulated BALB/c mouse calvaria. These results suggest that both PGE2and IL‐1 participate in Y4 LPS‐induce

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01639.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Quantification of osteoclast resorption, a good index of periodontitis destruction, is primarily based on osteoclast identification. As their identification is sometimes dubious, we compared osteoclastic counts in hamster specimens processed for either routine histology or tartrate‐resistant acid phosphatase (TRAP) staining. No difference was found between the two approaches concerning the number of osteoclasts. However the mean bone‐osteoclast interface was higher in the TRAP‐stained specimens (+ 30%, p<0.02). As osteoclast precursors are also TRAP+ cells, they were quantified too. Compared with controls, there was a dramatic increase (p<0.0001) in periodontitis‐affected animals. Precursors were strongly correlated to active osteoclasts (r = 0.97). Our data suggest that precursors are recruited only when the disease is active in a giv

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01640.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Relative avidities of antibodies toPorphyromonas (Bacteroides) gingivalisin the sera of 15 patients having adult periodontitis and 15 healthy subjects were evaluated using an ammonium thiocyanate‐dissociated ELISA. Graded concentrations of ammonium thiocyanate were added to a single dilution of serum in order to dissociate low avidity antibody binding toP. gingivalis. The concentration of thiocyanate resulting in 50% reduction in binding (absorbance) was termed the ID50for that serum. When IgG‐class antibodies were examined, the ID50of anti‐P. gingivalisantibodies in the sera of patients was significantly elevated (0.96M vs 0.71M; p<0.01, Student's t‐test). In contrast, when IgM‐class antibodies were examined no significant differences in ID50between patients and controls were found forP. gingivalis(0.54M vs 0.53M). While the ID50values of patient antibodies were found to be elevated relative to those of healthy controls, comparison with antibodies from rabbits immunized withP. gingivalisand with ID50values from other human studies suggests that adult humans, in general, produce very low‐avidity antibodies toP. gingivalis. It is suggested that the presence of low‐avidity antibodies contributes to the pathology associated with period

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01641.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

This paper presents a computer model of periodontal breakdown based on 1/f noise. The model is multifactorial and simulates the disease advancing with age in bursts and remissions, as seen in previous epidemiologic studies. Changing the weight of some parameters changed the simulated periodontal breakdown dramatically, disclosing antagonistic and synergistic effects between the causal factors.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01642.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

A single‐blind investigation was designed to study the effects of piroxicam in preventing gingival inflammation and plaque formation in beagle dogs. Twelve 1‐year‐old beagles were brought to optimum oral hygiene and gingival health. Thereafter, they were fed a moist plaque‐promoting diet and were divided into three groups. The first group received daily administration of 1.0 ml placebo gel (methylcellulose) painted on the teeth. The second group received 1.0 ml of gel containing 2 mg/ml piroxicam and the third group received 1.0 ml liquid containing 2 mg/ml of piroxicam. Placebo and test solutions were applied daily, and dogs were examined biweekly for evaluation of plaque accumulation, gingival inflammation, bleeding upon gentle probing and tooth staining. Data were analyzed using the Krushkal‐Wallis test. Over the treatment period, plaque accumulation was substantial in all three groups and was not significantly different between the three groups. By week 2, the gingival index in the piroxicam‐treated dogs was significantly lower than that of the placebo‐treated group and remained so throughout the study, with the exception of wk 6 and 12 in the topical gel‐treated group. Mean percent bleeding sites were also significantly less in the piroxicam‐treated groups than in the control dogs. Staining of the teeth increased for all groups over the 16‐wk treatment period. These data indicate that piroxicam can significantly inhibit the development of gingival inflamma

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01643.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Porphyromonas gingivalisfrom the human oral cavity was serologically characterized using absorbed and unabsorbed rabbit antisera. The reference strains were ATCC 33277, W50, W83, 381 and hara 1. The 432 isolates were from periodontal pockets of 63 patients with adult periodontitis. Using sonicated antigens, four serotypes were identified by immunodiffusion tests and immunoelectrophoresis. Each patient harbored only one serotype ofP. gingivalis, and serotypes I and IV predominated. The incidence of serotype I was four times higher than that of serotype II, and approximately seven times higher than that of serotype III. The collagenolytic and some proteolytic enzymes of representatives of each serotype were assessed. Although all strains produced these enzymes to some degree, some differences in their levels were observed. Serotype II strains were more collagenolytic than serotypes I or III, and serotype III exhibited lower activities of N‐CBz‐glycyl‐glycyl‐arginyl peptidase than other serotypes. Antibiotic sensitivity was also compared with antimicrobial disks, and serotype IV strains exhibited high sensitivity to the four antibioti

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01644.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01645.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY