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At least 19 recordsLinked to original sources
PubMed1979

Effect of mechanical plaque control on development of subgingival plaque and initial gingivitis in neutropenic dogs.

Histologic, histometric and morphometric investigations were performed on the gingival tissues of three neutropenic dogs. Over a period of 4 d the animals had been subjected to daily toothcleaning of the left side of both jaws, whereas plaque accumulation and subsequent gingivitis occurred on the uncleaned teeth of the right side of both jaws. Observations and data revealed that subgingival plaque had formed in both sides and extended further apically (max. 0.6 mm) on the cleaned than on the uncleaned sides. In the responding gingival tissues, leukocytes of the junctional epithelium were more numerous and blood vessels of the marginal connective tissue occupied a greater volume on the cleaned sides when compared with the uncleaned sides. It is concluded that neutrophilic granulocytes normally help to prevent bacterial invasion into the dentogingival region, and that, in the presence of subgingival plaque, toothcleaning may aggravate the inflammatory response of the gingiva.

Agranulocytosis↗
PubMed1979

The infrabony pocket and its relationship to trauma from occlusion and subgingival plaque.

The role of trauma from occlusion and subgingival plaque in the pathogenesis of the infrabony pocket as observed in the radiograph was studied in 48 teeth which had to be extracted because of advanced periodontal disease. Prior to extraction the teeth were examined with regard to the degree of mobility and the direction of the horizontal components of the masticatory forces. Following extraction, the teeth were stained and examined under the stereomicroscope. When the tooth is adequately stained, the subgingival plaque and the remaining attachment fibers can be distinguished easily from the area of the junctional epithelium. The observations which were made on the extracted teeth were then correlated with what could be seen in the radiograph. The following major observations were made: In the depth of the infrabony pocket there was a close congruence between the front of the subgingival plaque and the borderline of the remaining attachment fibers, the distance varying between 0.2 and 2.0 mm. There was also a close relationship between the front of the subgingival plaque and the alveolar crest adjacent to the tooth as well as between the surface of the subgingival plaque and the opposite vertical wall of the infrabony pocket, the distances ranging between 1 and 3 mm. The horizontal forces were mainly or exclusively oriented bucco-lingually, whereas the infrabony pockets were located mesially or distally, i.e. parallel to the direction of the force and not at a right angle to it as observed in experimental studies. The mobility of the teeth adjacent to which infrabony pockets developed was normal in 42% of the cases, slightly increased in 31%, and only in 11% of the cases was it excessively increased. In 19 cases the infrabony pocket was located on one of the roots of lower molars which were removed by hemisection. In eight of the 12 cases, which were observed for periods from 1 to 10 years, the remaining root functioned well without further development of angular bone defects or infrabony pockets. All of them became markedly firmer as a consequence of successful periodontal treatment. Three of the four remaining roots were extracted because of periapical problems. There was no evidence to indicate that trauma from occlusion had been involved in the pathogenesis of the infrabony pockets.

Adult↗
PubMed1977

Subgingival plaque and loss of attachment in periodontosis as evaluated on extracted teeth.

The correlation between downgrowth of subgingival plaque and loss of attachment was evaluated on 27 teeth which had to be extracted because of advanced bone loss in 16 patients between ages 12 and 22. The diagnostic criteria were those used for periodontosis. The teeth were stained and examined under the stereomicroscope. There was a very high degree of congruence between the subgingival plaque front and the line of lost attachment on all the teeth, thus showing that plaque is strongly involved in the destruction of the attachment apparatus. On some of the vestibular and lingual surfaces where efficient supragingival plaque control had been maintained, there was no subgingival plaque and no loss of attachment, showing that subgingival plaque develops from supragingival plaque. The highest speed of apical growth of the subgingival plaque front in any one case was estimated to be about 5 mu per day, or about 1,8 mm per year. Such an unusually rapid advancement must be the combined effect of an extremely high invasiveness of some inhabitants of the plaque and some deficiency in the host's defense mechanism against the same organisms. The subgingival plaque was found to be very thin and only occasionally calcified to form calculus. Symptoms of inflammation, if any, were only seen at the gingival margin, giving the clinical impression of a noninflamatory, degenerative condition. This explains why the concept of diffuse atrophy has developed. The observations made in this material indicate that what has been diagnosed as periodontosis, in fact is a highly destructive juvenile periodontitis which should be so named. The high destructiveness depends on a host parasite imbalance rather than on a degenerative condition.

Adolescent↗
PubMed1979

The angular bone defect and its relationship to trauma from occlusion and downgrowth of subgingival plaque.

Sixty-four sets of human teeth were collected with the aim of evaluating the role of trauma from occlusion in the etiology of destructive periodontal disease. Before the jaws were taken out, a careful bite analysis was carried out. After fixation of the jaws, impressions were taken and plaster of Paris models were made. Finally, a set of 14 radiographs were taken. On the basis of the "clinical" records postmortem, the study models and the radiographs, the jaws were sectioned. Only mesio-distal sections were included in the present analysis. The total number of interdental spaces examined was 106. The following observations were made: 1. Before any loss of periodontal fiber attachment has taken place, the configuration of the interdental septum is entirely dependent on the location of the cemento-enamel junction (CEJ) of the two neighboring teeth. The alveolar crest does not approach the apical border of the junctional epithelium closer than about 1 mm. Thus, if the CEJ is located at different levels on two neighboring teeth, the marginal termination of the interdental septum will be oblique, forming an acute angle with the "lowest" tooth. 2. Loss of periodontal fiber attachment could invariably be related to the apical growth of subgingival plaque, and downgrowth of plaque was always associated with an inflammatory process which involved lysis of the attachment fibers within a distance varying between 0.2 and 1.8 mm from the apical border of the plaque. Subsequently, the JE proliferated down to cover the denuded root surface. 3. Reduction in height of the alveolar crest could also be related to the downgrowth of plaque. The distance from plaque to bone was never found to be less than 0.5 mm and never more than 2.7 mm. The configuration of the interdental septum always seemed to be determined by the level of the plaque on the two neighboring tooth surfaces. Thus, if the plaque had reached the same level on both sides, the crest of the interdental septum assumed a horizontal outline; if plaque had proliferated down to different levels, the crest of the interdental septum was oblique and an angular defect hereby established. 4. In the present material no evidence was found to indicate that functional (traumatic) forces can act as a co-factor in the causation of angular defects. In fact, such defects were found equally often adjacent to "nontraumatized" as to "traumatized" teeth. 5. Infrabony pockets were invariably associated with downgrowth of subgingival plaque.

Dental Occlusion, Traumatic↗
PubMed1977

A scanning electron microscopic study of the relationship between the most apically located subgingival plaque and the epithelial attachment.

Twelve teeth with chronic periodontitis were extracted and examined in the scanning electron microscope. Subgingival plaque in deep pockets was usually covered by a surface coating, which was absent in the apical part. The apical plaque displayed an organized structure, although varying form one tooth to another. The microorganisms were sometimes overlapping the epithelial cell remnants. Coccal forms were seldom found, but on a morphologic basis, rod-like, filamentous, spiral and branching forms were identified. Both bacteria and spirochetes seemed to have the capacity to invade the epithelial remnants on the tooth surface. The epithelium in direct contact with the microorganimsm showed a widening of the intercellular spaces and a change in surface morphology. This was in contrast to cell layers more distant from the plaque, which appeared normal and homogeneous. Similar reactions were also seen in gingival epithelial-like cell cultures infected with plaque of human origin.

Bacteria↗
PubMed1977

Interaction of inflammatory cells and oral microorganisms. IV. In vitro release of lysosomal constituents from polymorphonuclear leukocytes exposed to supragingival and subgingival bacterial plaque.

The deposition of bacterial plaques on tooth surfaces appears to be responsible for the initiation and progression of periodontal disease. In this study, human peripheral blood polymorphonuclear leukocytes (PMNs) actively released lysosomal constituents upon in vitro exposure to either viable or irradiated, supragingival or subgingival dental plaque. Plaques were obtained from the PMN donors (autologous plaque) or from pooled samples (homologous plaque) secured from patients with periodontal lesions. Fresh sera from PMN donors amplified the release reactions to supragingival and subgingival plaques. Heated (56 degrees C, 30 min) sera also enhanced release reactions, but not as consistently as fresh serum. It was postulated that modulation of PMN release by serum is mediated by complement components and/or antibodies to plaque bacteria. Electron microscopic observations indicated that degranulation and discharge of PMN lysosomal enzymes may be associated with phagocytosis of gram-positive and gram-negative plaque bacteria and with reverse endocytosis of lysosomes from cells contacting relatively large masses of aggregated plaque bacteria. These data suggest that PMN lysosome release in response to plaque may serve as a potential mechanism of tissue injury in the pathogenesis of gingival and periodontal inflammation.

Bacteria↗
PubMed1977

Plaque control in the treatment of juvenile periodontitis.

With the purpose of establishing to what extent "periodontosis" responds to total plaque control, 21 such patients were observed over periods ranging from 8 to 34 years. Total plaque control in the present context means complete removal of all supragingival plaque by the patient and complete removal of all subgingival plaque by the dentist. The results were evaluated in terms of the number of lost teeth and the percentage of lost attachment during the observation period. It was observed that "periodontosis" cases responded to total plaque control in the same way as do ordinary cases, but with periodontosis, incomplete plaque control on any teeth led to extremely rapid bone loss and eventually to extraction. The reason for this is the unusually rapid apical migration of the subgingival plaque which is the most typical feature of the juvenile periodontitis. Some attachment and some teeth were lost in most of the patients, but a sufficient number of teeth with a sufficient amount of supporting tissue were maintained to provide a set of natural teeth that functioned well. This study shows that the reduced resistance to the invasion of subgingival plaque can be compensated for by a correspondingly strong emphasis on total plaque control. The term "periodontosis" is misleading, and should be replaced by the name "juvenile periodontitis" as suggested by Lehner et al. (1974).

Adult↗
PubMed1979

Effect of experimental neutropenia on initial gingivitis in dogs.

The role of neutrophilic granulocytes in the loss of gingival collagen has been studied by inducing experimental neutropenia during initial gingivitis in beagle dogs. Neutropenia was induced for 4 d in three animals with normal gingiva by repeated injections of rabbit anti-neutrophil serum. During neutropenia microbial plaque was allowed to form on the teeth. Samples of junctional (crevicular) leukocytes and gingival fluid were taken on days 0 and 4. Block biopsies of buccal gingiva were obtained on day 4. Stained semi- and ultrathin sections were used for histometric and stereologic tissue analysis. Gingival fluid flow increased from day 0 to day 4 in all dogs while junctional leukocytes increased in one dog only. Subgingival plaque had formed in most biopsies, and in the junctional epithelium very few neutrophilic granulocytes were present. In the coronal connective tissue subjacent to the junctional epithelium lymphoid cells, structurally abnormal neutrophilic granulocytes and monocytes/macrophages were diffusely scattered. The gingival collagen appeared mainly displaced by the inflammatory cells rather than dissolved. The data suggest that neutrophilic granulocytes may contribute to the loss of gingival collagen during initial gingivitis in dogs. The neutrophils also seem to be of importance for the limitation of subgingival plaque growth along the tooth surface.

Agranulocytosis↗
PubMed1979

Medium for selective isolation of Fusobacterium nucleatum from human periodontal pockets.

A selective medium, CVE agar, was developed for the isolation of Fusobacterium nucleatum from subgingival plaque of periodontally diseased patients. The medium contained 1.0% Trypticase (BBL Microbiology Systems), 0.5% yeast extract, 0.5% NaCl, 0.2% glucose, 0.02% L-tryptophan, 1.5% agar, and 5% defibrinated whole sheep blood. Erythromycin and crystal violet were added as the selective inhibitory agents at concentrations of 4 and 5 micrograms/ml, respectively. The medium permitted almost total recovery of F. nucleatum when compared with a nonselective medium and suppressed the recovery of most remaining species by nonselective medium and suppressed the recovery of most remaining species by 6 to 8 orders of magnitude. Microorganisms suppressed to a lesser degree included Selenomonas sputigena, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and some strains of Peptostreptococcus. The distinct colonial morphology of F. nucleatum on CVE agar made differentiation relatively easy when contaminants were present. With this medium, F. nucleatum was enumerated from 278 subgingival plaque samples and accounted for less than 1.0 to greater than 25% of the cultivatable microbiota.

Adolescent↗
PubMed1979

Simplified technique for sonication and processing of dental plaque samples.

A simplified method for processing dental plaque samples was devised and compared to previously used methods. Analysis of 36 nonstandardized subgingival plaque samples from various states of periodontal health and disease and 12 standardized supragingival plaque samples demonstrated that there was no significant difference between the recovery offered by the two techniques. Comparable recovery, increased convenience, and adaptation to the clinical setting suggests that implementation of this simplified technique may be of great value.

Aged↗
PubMed2026

"Clinical efficacy and expression of antimicrobial resistance genes after using a novel herbal mouthwash compared to chlorhexidine: A Randomised controlled trial in generalised gingivitis patients".

OBJECTIVES: Chlorhexidine, the gold-standard mouthwash, has several disadvantages, like promotion of antimicrobial resistance. Herbal mouthwashes are emerging as alternatives to chlorhexidine. However, its impact on antimicrobial resistance remains unclear. The aim of the study was to compare the clinical efficacy and the expression of antimicrobial resistance genes of chlorhexidine with a novel herbal mouthwash. DESIGN: Sixty patients with generalised gingivitis were randomly assigned to two groups using block randomisation. After professional mechanical plaque removal patients were instructed to use either chlorhexidine or a novel herbal mouthwash (patented composition) for two weeks. Tetracycline resistance (tetM) and macrolide efflux (mefI) gene expression in subgingival plaque were analysed using real-time polymerase chain reaction. Intragroup comparisons were performed with a paired t-test and Wilcoxon signed-rank test for parametric and nonparametric data. Intergroup comparisons employed unpaired t-test, chi-square test, and Mann-Whitney test. RESULTS: A significant reduction in bleeding, plaque, pocket depth and and patient reported outcomes were noticed in both groups. But reduction in plaque was more significant in chlorhexidine group. tetM and mefI genes significantly upregulated in the chlorhexidine group, while it was downregulated with herbal mouthwash (fold change 1.79 ± 0.74 and 0.60 ± 0.43 for tetM, and 1.83 ± 0.87 and 0.51 ± 0.44 for mefI). However, patients' perception of taste, freshness, and overall satisfaction was better in the chlorhexidine group. CONCLUSIONS: The increased expression of antimicrobial resistance genes following chlorhexidine use warrants careful consideration. Herbal mouthwash is an effective, safer alternative with comparable clinical benefits and less impact on antimicrobial resistance.

Humans↗
PubMed1978

Attachment of Bacteroides melaninogenicus subsp. asaccharolyticus to oral surfaces and its possible role in colonization of the mouth and of periodontal pockets.

This investigation examined the ability of cells of Bacteroides melaninogenicus subsp. asaccharolyticus 381 to adhere to surfaces that might be important for its initial colonization of the mouth and its subsequent colonization in periodontal pockets. Of 48 asaccharolytic strains of B. melaninogenicus, 47 agglutinated human erythrocytes, whereas none of 20 fermentative strains, which included reference cultures of the subspecies intermedius and melaninogenicus, were active. Electron microscopy indicated that both asaccharolytic and fermentative strains possessed pili; hence, the presence of pili did not correlate with the hemagglutinating activities of B. melaninogenicus strains. Both asaccharolytic and fermentative B. melaninogenicus strains suspended in phosphate-buffered saline adhered in high numbers to buccal epithelial cells and to the surfaces of several gram-positive bacteria tested, including Actinomyces viscosus, A. naeslundii, A. israelii, Streptococcus sanguis, and S. mitis. B. melaninogenicus subsp. asaccharolyticus 381 also attached, but in comparatively low numbers, to untreated and to saliva-treated hydroxyapatite. Addition of clarified whole saliva to suspensions of strain 381 almost completely eliminated adherence to buccal epithelial cells and to hydroxyapatite surfaces, but saliva had no detectable effect on attachment to gram-positive plaque bacteria. Both fermentative and nonfermentative strains of B. melaninogenicus also attached in high numbers to crevicular epithelial cells derived from human periodontal pockets, but normal human serum strongly inhibited attachment. Serum also inhibited attachment of strain 381 to saliva- and serum-treated hydroxyapatite, but it had little effect upon attachment to gram-positive bacteria. These observations suggested that salivary and serum components would strongly inhibit the attachment of B. melaninogenicus cells to several oral surfaces, but not to the surfaces of certain gram-positive bacteria commonly present in human dental plaque. This was confirmed by an in vivo experiment in which streptomycin-labeled cells of B. melaninogenicus 381-R were introduced into the mouths of two volunteers. After 10 min, several hundred-fold higher numbers of the organism were recovered from preformed bacterial plaque present on teeth than from clean tooth surfaces or from the buccal mucosa and tongue dorsum. High numbers of B. melaninogenicus cells were also recovered from preformed plaque after 150 min, but virtually no cells of the organism were recovered from the other surfaces studied. These data suggest that the presence of dental plaque containing Actinomyces and other gram-positive bacteria may be essential for the attachment and colonization of B. melaninogenicus cells after their initial introduction into the mouth. Similarly, the presence of subgingival plaque containing gram-positive bacteria may be necessary for its secondary colonization in periodontal pockets.

Adult↗
PubMed1977

Surgical pocket therapy.

(1) Periodontal pockets can be treated successfully by several modalities of surgery. (2) Periodontal pocket walls do not have to be eliminated surgically in order to stop the progress of periodontal disease. (3) A residual defect which can be probed beyond 3 mm at the site of a previous peridontal pocket, does not signify a progressive lesion as long as it does not appear inflamed or contain, exudate and bleeds when probed. (4) The most important aspect of all pocket therapy is to make the exposed root surface biologically acceptable to the surrounding soft tissues. (5) The gingiva should be so closely adapted to the teeth at the end of the healing following treatment that subgingival plaque does not colonize to the extent of being recognizable clinically. (6) Frequent professional prophylaxis is of paramount importance for success of all pocket therapy.

Alveolar Process↗