摘要:

Initial Colonization and early plaque formation were studied using hydroxyapatite splint segments attached to buccal surfaces of maxillary molar and premolar teeth in six young adults given a low‐sucrose diet. Segments were removed at intervals of 2, 4, 6, 12, 24 and 48 hr. Bacteria were first regularly seen in 4 or 6 hr specimens where they occurred as individual cells or as small groups of cells. No structures resembling preformed aggregates or hemispherical bacterial “globules” could be demonstrated. The bacteria most frequently attached to the pellicle surface diectly by their cell wall and gram‐positive cocci were most abundant. Another mode of bacterial attachment to pellicle was by means of fine bifbrils or coarser thread‐like structures. Occasionally organisms were seen attaching to apatite surfaces without interjacent pellicle material and sometimes they appeared to be completely embedded in the pellicle. Bacteria colonizing on epithelial cells regularly displayed a “fuzzy coat”. Extensions of organic material from the pellicle surface sometimes made it difficult to distinguish between pellicle and plaque matrix. No clear indication of bacteria metabolizing the pellicle was seen. Trilaminar vesicles probably originating from the surface of degenerating cells were especially abundant in areas with Gramnegative bacteria. In areas with Gram‐positive cells the amount of plaque matrix was greater and a number of cells displayed surface threads. The outer surface of the plaque ordinarily did not show a layer of extracellular organic material although a granular laer could be seen in local areas. These findings lend support to a concept of plaque formation as a sequential build‐up resulting from selective attachment and growth of individual organisms rather than resulting from attachment of aggregates of bacteria or a passive entrapment of orga

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00194.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

The aim of the present study was to compare the structural composition of the gingiva of dogs which had not previously suffered from inflammation with that of gingiva which for 6 months had been inflamed, but subsequently healed. The experiments were carried out in eight dogs. After weaning, the dogs were daily subjected to tooth cleaning. When the animals were 10 months old a clinical examination was carried out after which the dogs were randomly distributed into two groups, A and B. Immediately after the clinical assessments, gingival biopsies were obtained from the premolars and molars of the dogsof Group A. The dogs of Group B were allowed to accumulate plaque during a 6‐month period after which the examinations were repeated and biopsies were sampled from predetermined areas of the dentition. Following biopsy the remaining teeth of the dogs of Group B were scaled. During the subsequent 6 weeks, the animals were daily subjected to tooth cleaning. The examinations were repeated and biopsies sampled on days 4, 7, 14, 21, 28 and 42. The biopsy material was subjected to morphometric analysis. The resuls showed that it is possible to shift a chronically inflamed gingiva into one which, from a clinical and structural point of view, is almost identical to a gingiva which has never been exposed to gross plaque accumulation. This shift was achieved by elimination of calculus and plaque and by the institution of a careful, daily practiced plaque control program. During healing, the inflammatory cell infiltrate in the connective tissue below the junctional epithelium gradually disappeared and became replaced by collagen. In comparison to inflamed gingiva during healing, the leukocyte content of the junctional epithelium was reduced, whle ee peg formations remained. In the connective tissue papillae beneath these rete pegs, vessels could be recognized. This gave the connective tissue of the healed gingiva a higher vascular content thatn that of a gingiva which had not previously suffered from inflammatio

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00195.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

The characteristic hemagglutination (HA) ofLeptotrichia buccaliswas used for measuring its attachment to various human cells and for determining if saliva contained hemagglutination inhibition (HI) factors. The microbial strain utilized displayed the chaacteristic EM morphology of L.buccalis. Sonicated preparations of the organism were tested for HA activity before and after adsorption with human cells. Buccal epithelial cells, red blood cells (RBC), HeLa and embryonic kidney cells all bound the HA fragments of the organisms. The bacterial fragments on the cells could be observed by fluorescent antibody testing. The fragments were released from the cells used for adsorption with chelators and upon addition of CaCl2 the HA activity returned. Whole saliva displayed hemagglutination inhibition activity in a manner suggesting a binding site interaction. The similarity of the HA activity of F.nucleatumis discussed as ae the relationships of cell binding to colonization of the organisms and immunopathology to host cells.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00196.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Lymphocyte membrane‐associated IgG subclass antibodies in human periodontal disease were studied to ascertain the elative presence of cytophilic IgG antibodies and the membrane Fc receptors which bind them. The experimental approach correlated the efect of incubating gingiva in tissue culture medium to remove cytophilic antibodies with the changes in the number of Fc receptors detectable after washing. The evidence indicated that the majority of lymphocytes in mild gingivitis lesions lacked cytophilic IgG antibodies as well as Fc receptors. IN severe gingivitis, the number of IgG subclass bearing lymphocytes increased to about half of the total lymphoid population, while the perentage of Fc receptor bearing cells remained qite low (12.3%± 3.2, S.E.). The majority of IgG subclass bearing lymphocytes had membrane IgG which serve as receptors for antigen; such cells are classically defined as bone marrow (B) derived lymphocytes and serve as the progenitor for plasma cells. Gingival specimens for patients with periodontitis were found to contain the highest percentage of Fc receptor bearing lymphocytes (38.3%± 12.6 S.E.) and cytophilic IgG antibodies. The findings indicae tha the clinical stages of human perodontal disease are characterized by different populations of infiltrating lymphocy

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00197.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Experiments were performed to study the effect of stimulation of salivary antibody on the progress of periodontal bone loss in monoinfected rats. Animals were immunized with formalin‐killedS. mutans,A. naeslundiiorA. viscosusin the region of each major salivary gland and then inoculated orally with live homologous organism. Salivary and serum antibody activities were measured by microagglutination. The contribution of IgA to the activity in saliva was further assessed by antiglobulin augmentation with class specific antiglobulin eagents directed to rat immunoglobulins. In certain experiments the presence of delayed hypersensitivity was investigated by skin testing. Periodontal bone loss was assessed by measurement of both horizontal and vertical bone loss. Estimation of the number of bacteria colonizing the teeth at the termination of each experiment was also made. Inexperiments withS. mutansorA. naeslundii, when relatively high levels of salivary antibody directed to the homologous organism were elicited by local injection, definite trends toward reductions in periodontal bone loss occurred. Serum antibody was also present in immunized animals. Fewer bacteria were generally recovered from immunized rats than from sham‐immunized rats. Delayed hypersensitivity toA. viscosuswas accompanied by an increase in vertical bone loss. It is suggested that inflammatory lesions contributing to periodontal disease might be modified by manipulation of the host's immune sys

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00198.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

In four patients with juvenile periodontitis (group A), five adults with advanced periodontitis (group B), and in four controls (group C) the concentration of serum immunoglobulins, serum complement (C3C4, and C5) T and B lymphocyte ratio, leukocyte migration inhibition and lymphocyte transformation responses to dental plaque bacteria (A. viscosus, B. melaninogenicus, F. nucleatum, and V. parvula) and PPD or PHA, and lymphocyte ATP‐ase activity were assessed before and during development of experimental gingivitis.All the patients in group A and B Had completed extensive periodontal treatment, and at the time of the experiment the periodontal conditions were excellent. Plaque accumulation and gingival inflammation were assessed and blood samples were drawn: at day 0; after plaque accumulation for 14 d (no oral hygiene) (period I); after 14 d with optimal oral hygiene (period II); after plaque accumulation for 14 d (no oral hygiene) and concomitant immunostimulatory treatment with levamisole (period III); after 14 d with optimal oral hygiene. After period I, gingival inflammation and increased gingival fluid flow developed in all groups; however, in group C some of the clinical and immunological responses were slightly enhanced as compared wiht group A and group B. On the other hand, after period III (plaque accumulation + levamisole) more pronounced clinical and immunological changes were recorded in group A and B than in group C, including a significant rise in gingival fluid flow, LIF production, and lymphocyte ATP‐ase activity. The present study has supported the asumption that a state of immunodeficiency can be an underlying, predisposing factor for juvenile periodontitis. The results, however, give only vague information on the nature of this defici

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00199.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Several cationic, mixed and amphoteric surfactants were tested for their antimicrobial activity and ability to inhibit the formation of in vitro plaque by oral microorganisms. All had antimicrobial activity against Actinomyces viscosus. Actinomyces naeslundii and Streptococcus mutans. Cationic surfactants were comparable to chlorhexidine in antimicrobial activity but were less effective in inhibiting plaque formation. Amphoteric surfactants were less effective than other detergents in antibacterial activity and had very limited capacity for the inhibition of plaque formation. Comparison of drug structure provides evidence that surfactant substantivity to saliva‐coated enamel is a cation active process. Saliva was found to have an antagonistic effect on the activity of cetylpyridinium chloride but not on Triburo

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00200.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1978.tb00201.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY