摘要:

Tetracyclines have recentlybeen shown to inhibit the activity of some but not all mammalian matrix metalloproteinases believed to mediate periodontal destruction. However, the specificity of this effect, which could have significant therapeutic implications for different periodontal diseases, has not been examined in detail. Doxycycline and 4de‐dimethylaminotetracycline (CMT‐1) have been tested in vitro for their ability to inhibit human neutrophil and fibroblast interstitial collagenases and collagenase in human gingival crevicular fluid (GCF). The GCF samples were obtained from systemically healthy and insulin‐dependent diabetic adult Periodontitis patients and from localized juvenile Periodontitis (UP) patients. The concentrations of these 2 tetracyclines required to inhibit 50% of the collagenase activity (IC50) were found to be 15 to 30 μM for human neutrophil collagenase and for collagenase in GCF of systemically healthy and diabetic adult Periodontitis patients. These concentrations approximate the tetracycline levels observed in vivo during treatment with these drugs. In contrast, human fibroblast collagenase and GCF collagenase from UP patients were both relatively resistant to tetracycline inhibition; the IC50for doxycycline and CMT‐1 for these 2 sources of collagenase were 280 and 500 μM, respectively. Based on these and other findings, we propose the following: 1) that systemic levels of tetracycline may inhibit connective tissue breakdown by inhibiting neutrophil collagenase; 2) that tetracyclines do not inhibit fibroblast‐type collagenase, which may help explain their lack of effect on normal connective tissue remodeling; 3) that tetracycline inhibition of collagenases may serve to identify the cellular origin of the enzyme; and 4) that tetracyclines can also prevent the oxidative activation of latent human procollagenases. With regards to therapy, the anti‐collagenase property of tetracyclines may be an effective adjunct in targeting tissue breakdown in systemically healthy and diabetic adult Periodontitis patients. However, in juvenile Periodontitis the anticollagenase property of tetracyclines may be less important than the antimicrobial activity of the drug because of the relative resistance of fibroblast‐type collagenase to tetracycline inhibition.J Periodontol 1993; 64:82–88.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.82

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

In a random sample of subgingivaldental plaque samples from 375 blacks and 300 whites aged 65 and older, immunofluorescence assays for 3 target pathogens includingActinobacillus actinomycetemcomitans, Porphyromonas gingivalis, andPrevotella intermedia, and BANA enzyme analysis were carried out. Blacks had significantly greater proportions ofP. gingivalisandP. intermediain their subgingival plaque and had significantly higher BANA scores. These assay results were investigated for concordance with each other and with 2 cariogenic salivary bacteria,Streptococcus mutansand lactobacilli. In general for both races, the periodontal pathogens were more likely to occur in combination with each other than with eitherS. mutansor lactobacilli.P. gingivalisandP. intermediawere more frequently associated with each other than withA. actinomycetemcomitans. There was a significant negative concordance between BANA andA. actinomycetemcomitansin whites and a significant positive concordance between BANA andP. intermediain blacks.J Periodontol 1993; 64:89–94.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.89

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

The presence of basement membranecomponents on the forming root surface suggests a role for this structure during cementoblast differentiation. The purpose of this study was to investigate the role of root‐associated basement membrane (RBM) in murine cementogenesis using tissue separation and recombination techniques. Root dentin specimens, with or without RBM, were combined with dental sac tissue, cultured for 2 weeks, harvested, and examined by light, immunofluorescence, and electron microscopy. Recombinations in which RBM was preserved on the root dentin surface were characterized by formation of an adherent mineralized tissue resembling acellular cementum; recombinations in which RBM was excluded were characterized by formation of mineralized tissue which did not adhere to the root dentin surface. These results suggest that formation of an adherent mineralized tissue on the developing root dentin surface is dependent upon the presence of indigenous basement membrane components.J Periodontol 1993; 64:95–102.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.95

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

The purpose of this studywas to compare the effectiveness of polylactic acid (PLA) granules as an alloplastic grafting material to that of decalcified freeze‐dried bone allograft (DFDBA) and a flap procedure for debridement without graft (FPD) when treating periodontal intrabony defects. Ten patients presenting with advanced adult Periodontitis, including at least 3 similar periodontal osseous defects (2‐ and 3‐walled), comprised the study group. After completion of a hygienic phase of treatment, measurements were made with calibrated periodontal probes and Stents to determine soft tissue recession, probing pocket depths, and probing attachment levels. Each defect was surgically exposed and hard tissue measurements were obtained. Defects were treated with one of the 3 methods above chosen randomly prior to the surgical appointment. Six months postsurgery, soft tissue measurements were repeated and all sites were surgically reentered to obtain hard tissue measurements. All surgical sites healed without clinical complication. The initial pocket depths and initial depth of osseous defects were compared between the groups using ANOVA and no significant differences were found. A mean osseous defect fill of 0.4 mm (11.2%) occurred with the flap procedure for debridement, 3.0 mm (65%) with DFDBA, and 0.1 mm (2.2%) with PLA. Mean crestal bone loss was 1.30 mm for FPD, 0.60 mm for DFDBA, and 1.55 mm for PLA. No statistically significant differences were found in soft tissue recession between groups or in the osseous defect measurement between PLA and FPD. A statistically significant improvement (P<0.001) was found in the fill of the osseous defects when using DFDBA compared to the initial defect depth and to the other 2 groups. Probing depths decreased a mean of 3.4 mm with FPD, 4.15 mm with DFDBA, and 1.8 mm with PLA. DFDBA produced the greatest amount of osseous defect fill, FPD less fill, and PLA the least amount of fill.J Periodontol 1993; 64:103–109.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.103

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

This study showed histopathological findingsof the extracellular matrix in healthy, inflamed, and hyperplastic human gingiva with immunohistochemical techniques. The distribution of collagen types V and VI, as well as of glycoprotein fibronectin, shows that they are extracellular matrix structural components which differentiate the tissue pathology. The orientation of the collagen fibers, the intensity of the fluorescent staining, the thickness of the fibrillar component, and the topographical localization of the connective tissue proteins are important parameters for tissue morphology. Therefore, bacterial deposits and the pharmacodynamic properties of drugs associated with gingival hyperplasia lead to an alteration of the matrix compared to the healthy tissues. This may be important in the tissue pathology in cases when the medical history of the patient is not known, as well as in forensic medicine.J Periodontol 1993; 64:110–119.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.110

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

Rapidly progressive periodontitis(RPF) has been suggested as a distinct clinical entity within the spectrum of early onset Periodontitis. Immunological mechanisms have been considered in the pathogenesis of RPP. This study was designed to evaluate the distribution and phenotypic properties of the lymphocyte populations within the affected gingival tissue of patients with RPP. Biopsies were obtained from 16 patients between 22 and 33 years of age. The tissue samples were processed for both histopathological and immunohistochemical examinations. Gingival tissue T lymphocytes (CD3+), helper T cells (CD4+), suppressor‐cytotoxic T cells (CD8+), and cells positive for HLA‐DR antigen were identified using monoclonal antibodies with an immunoperoxidase technique. Intracytoplasmic immunoglobulin‐containing cells were also stained immunohistochemically with polyclonal antibodies. CD3+cells were mainly located beneath the pocket epithelium. CD4+and CD8+cells were evenly distributed within this T‐cell infiltrate with a CD4+/CD8+ratio of 1:12. Numerous HLA‐DR+cells were also observed in the lymphocytic infiltrates. The majority of mononuclear cells located throughout the stroma were IgG+plasma cells. Our results indicate that RPP patients present an IgGbearing plasma cell dominated lesion with equal participation of both T‐cell subpopulations. These findings suggest that activation and proliferation of B‐cells play an important role in the pathogenesis of periodontal diseases.J Periodontol 1993; 64:120– 127.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.120

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

The purpose of this studywas to evaluate the potential of cryopreserved cancellous bone allograft (CCBA) in the treatment of intraosseous periodontal defects compared to surgical debridement alone (DEBR). Cancellous bone was procured from femur heads that had been extracted for hip prosthesis procedures and cryopreserved in liquid nitrogen (–196°C) in a tissue bank. Ten patients without systemic disorders and advanced periodontal disease (at least 2 intraosseous defects) participated in this investigation. Measurements from the cemento‐enamel junction were made after initial therapy for clinical attachment level; also gingival recession, probing pocket depth, plaque index, and gingival index and, at the time of surgery, alveolar crest height and osseous defect depth were measured. All measurements were repeated at 1 year‐reentry. Sixteen defects were debrided and grafted (test sites) and 13 defects were debrided only (control sites). Soft tissue measurements showed no statistical differences between the 2 groups. Defect fill was significantly greater with CCBA (1.75 mm) than with DEBR (0.56 mm). Defect depth reduction was 2.06 mm for CCBA and 0.78 mm for DEBR. These values correspond to a percent‐defect resolution of 60% for CCBA and 29% for DEBR. Hard tissue measurements showed significant differences between the 2 groups. CCBA seems to be effective in the short‐term treatment of intraosseous periodontal defects.J Periodontol 1993; 4:128–132.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.128

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

The purpose of this clinical trialwas to evaluate the effect of tetracycline root preparation on guided tissue regeneration in the treatment of Class II furcation defects. Nine pairs of defects with horizontal clinical attachment level value ≥5 mm comprised the study group. Measurements were made to determine presence of plaque, gingival condition, probing depth, and vertical and horizontal clinical attachment level. Defects from each pair were randomly assigned for treatment with an expanded polytetrafluoroethylene membrane (e‐PTFE) and tetracycline root conditioning (100 mg/ml) or the membrane alone. The membranes were removed 4 to 6 weeks postsurgery. Patients were then seen monthly for the duration of the study. Six months postsurgery, all clinical measurements were repeated. Following either treatment, improvement was observed in all clinical parameters, particularly in horizontal clinical attachment level. However, there was not a statistically significant difference in the improvement observed between sites treated with guided tissue regeneration in conjunction with tetracycline as compared to membrane placement alone. Further studies are needed to fully evaluate tetracycline root preparation in conjunction with regenerative therapy.J Periodontol 1993; 64:133–136.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.133

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

Substantivity of tetracyclineHCl and Chlorhexidine digluconate was assessed in extracted teeth. Fifty periodontally compromised teeth scheduled for extraction with probing depths ranging between 6 and 12 mm were root planed and then irrigated in situ with 1 of 4 solutions: tetracycline HCl at concentrations of 10 or 50 mg/ml, 0.12% Chlorhexidine digluconate, or 0.9% sterile saline. Each tooth was exposed to 150 ml of the respective irrigation solution. Following extractions, the teeth were transferred to tris buffered saline and incubated at room temperature for 22 days. Incubation solutions were replaced at 24‐hour intervals. Removed solutions were examined for desorbed antimicrobial activity using a microtiter assay in which bacterial growth was evaluated by optical density readings. Tetracycline HCl 50 mg/ml exhibited significantly greater antimicrobial activity than Chlorhexidine digluconate for 12 days and greater than saline for 16 days. Tetracycline HCl 10 mg/ml exhibited significantly greater antimicrobial activity than Chlorhexidine digluconate and saline for 4 days. Chlorhexidine digluconate did not exhibit any significant antimicrobial activity at any time point. Our findings demonstrate longlasting substantivity of tetracycline HCl, but not Chlorhexidine digluconate, by teeth exposed to a single episode of pocket irrigation of their periodontally‐exposed roots. The amount of antimicrobial activity retained is proportional to the concentration of tetracycline HCl used for irrigation.J Periodontol 1993; 64:137–141.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.137

出版商:Wiley    

年代:1993

数据来源: WILEY

摘要:

Periodontal regeneration is thoughtto require the migration and proliferation of periodontal ligament cells. Evidence suggests that the Polypeptide growth factors PDGF, IL‐1, and TGF‐β are mediators of these cellular events in wound healing. The purpose of this study was to determine the effects of these growth factors on human periodontal ligament (PDL) cell mitogenesis, and to identify the regulatory influences of TGF‐β on the response to PDGF and IL‐1. Confluent, quiescent human PDL cells were cultured in vitro and treated with the Polypeptide growth factors PDGF‐AA and ‐BB, IL‐1β, and TGF‐• in both a dose and time‐dependent manner. Mitogenic activity, as a measure of proliferative potential, was determined by the quantitation of3H‐thymidine incorporation during DNA synthesis. The results of this study demonstrated that both PDGF‐AA and ‐BB enhance mitogenic activity in a dose‐dependent manner over a concentration range of 1.0 to 50.0 ng/ml. IL‐1β (0.01 to 1.0 pM) resulted in no mitogenic enhancement, and at high concentrations (10.0 to 100.0 pM) demonstrated an inhibitory effect. TGFβ produced a significant increase (P<0.01) in mitogenic activity (although relatively much less than PDGF) in a delayed, bimodal, dose‐dependent manner over a concentration range of 0.01 to 20.0 ng/ml, with a maximal response at a concentration of 1.0 ng/ ml. Additionally, incubation with TGF‐β at 1.0 ng/ml prior to the addition of PDGF significantly enhanced (P<0.01) the mitogenic response to both PDGF‐AA and PDGFBB. In contrast, incubation with TGF‐β at a higher concentration (10.0 ng/ml) prior to PDGF addition resulted in a decreased (P<0.05) mitogenic response to PDGF‐AA, while enhancing (P<.01) the response to PDGF‐BB. This study demonstrates that PDGF‐AA and PDGF‐BB are major mitogens for human PDL cells in vitro, and supports a role for TGF‐β as a regulator of the mitogenic response to PDGF in these cells.J Periodontol 1993; 64:142–148.

ISSN:1049-8885    

DOI:10.1902/jop.1993.64.2.142

出版商:Wiley    

年代:1993

数据来源: WILEY