Clinical and light microscopic observations of gingivitis and early ligature-induced periodontitis in the cynomolgus monkey.

Clinical and histological observations were made on gingivitis and ligature-induced periodontitis in 4 adult female cynomolgus monkeys (Macaca fascicularis) to define the changes occurring in the early periodontitis lesion. Silk ligatures were tied around selected posterior teeth and replaced weekly for 4 weeks. The changes from gingivitis to periodontitis induced by ligation, and back to a state of clinical health after ligature removal, scaling and polishing, were characterized by Plaque Index, Gingival Index, probing pocket depth, attachment loss, and histologic evaluation. A mild, chronic marginal gingivitis was the normal finding in the gingiva of posterior teeth. The inflammatory infiltrate in the connective tissue contained primarily lymphocytes. Hygienic measures once a week reduced the amount of infiltrate and the epithelial proliferation, but did not eliminate it. Placement of silk ligatures rapidly changed the clinical picture to a moderate or severe gingivitis, which presented an almost bizarre response of sulcular and oral epithelium, with an increase in polymorphonuclear neutrophil infiltration. Within 2 weeks there was significant probing attachment loss. The clinical response on removal of ligatures and plaque was almost as rapid as the onset. The animal model is useful for manipulating variables in ways not possible in the study of human periodontitis.     

Morphological studies on periodontal disease in the cynomolgus monkey

Histologic observations were made on the primate Macaca fascicularis in order to describe the features of both naturally-occurring gingivitis and gingivitis present at non-experimental sites when selected teeth were ligated to induce periodontitis. Semi-thin sections of glutaraldehyde-paraformaldehyde fixed, EDTA-decalcified, and epon-embedded specimens were used, supplemented by routine histologic methods.
The microscopic picture of the interdental areas was identical for the two types of gingivitis specimens and consisted of a chronic inflammatory reaction resembling the established lesion in humans. The highly infiltrated gingival tissue exhibited a predominance of plasma cells. Leukocytes were seen in pathways from the connective tissue, through the epithelium and to the surface of the plaque, and many neutrophils were interposed between the plaque and soft-tissue. The apical extent of the junctional epithelium was at or slightly below the cemento-enamel junction. Although perivascular inflammation was observed in the transseptal fiber region, the alveolar crest exhibited only evidence of normal bone remodelling.     

DNA probe detection of periodontal pathogens in HIV-associated periodontal lesions

Recent studies have shown that an atypical gingivitis and a rapidly progressive periodontal disease may be early-occurring opportunistic infections associated with human immunodeficiency virus (HIV) infection. This study examined the prevalence of selected periodontal pathogens associated with these HIV-related periodontal lesions. Subgingival plaque samples were obtained from both HIV-seronegative and HIV-seropositive homosexual men and from presumably uninfected heterosexual men. DNA probes were used to detect Actinobacillus actinomycetemcomitans, Bacteroides intermedius, Bacteroides gingivalis, Eikenella corrodens and Wolinella recta in the plaque. The healthy sites in both the seronegative and seropositive homosexual groups showed a greater prevalence of all test bacteria, except for E. corrodens, than did the heterosexual group. HIV-associated periodontitis sites showed a microbial profile qualitatively similar to that of conventional periodontitis, except that B. gingivalis was more prevalent in conventional periodontitis. In contrast, HIV-associated gingivitis sites exhibited a greater prevalence of all bacteria tested than conventional gingivitis sites. In fact, HIV gingivitis generally showed a bacterial profile similar to that of the HIV periodontitis lesions, except that W. recta was significantly more prevalent in HIV periodontitis. These data suggest that the HIV gingivitis lesion is a precursor to HIV periodontitis. Thus, early identification and prophylactic treatment of high-risk individuals may prevent the destruction of periodontal tissues.     

The microbiology of ligature-induced periodontitis in the cynomolgus monkey

The cultivable subgingival microflora in the cynomolgus monkey, Macaca fascicularis , was monitored during the ligature-induced progression of naturally occurring gingivitis to periodontitis. Clinical and microbiological observations were divided into four stages. Stage I, prior to ligature placement, was characterized clinically by chronic generalized gingivitis and microbiologically by Gram-positive cocci and rods with B. melaninogenicus ss. intermedius the dominant Gram-negative organism. Stage II, 1 to 3 weeks following ligature placement, exhibited slightly greater gingival inflammation but no clinical evidence of attachment loss. The subgingival flora showed a significant increase in motile and surface translocating Gram-negative rods, primarily Capnocytophaga species and Campylobacter sputorum . Stage III, 4 to 7 weeks following ligature placement, revealed increased pocket depth and radiographic evidence of alveolar bone loss. This stage was characterized by a Gram-negative anaerobic flora with B. asaccharolyticus as the dominant cultivable organism. Stage IV encompassed the remainder of the experimental period, 8 to 17 weeks, during which time no further change in the clinical parameters occurred and levels of B. asaccharolyticus decreased.
The subgingival microflora of ligature induced periodontitis in Macaca fascicularis closely resembled that reported for human periodontal disease and the episodic clinical pattern of attachment loss was associated with levels of Gram-negative anaerobes, primarily B . asaccharolyticus .     

Systemic manifestations of periodontitis in the non-human primate

This report describes our findings regarding the potential contribution of periodontitis to atherosclerotic processes using a nonhuman primate model. The goal of the investigations was to target general mechanisms which could describe the association of these disease processes, including: (i) systemic translocation of bacteria/products during periodontitis; (ii) alterations in systemic inflammatory biomarkers during periodontitis; and (iii) the relationship of periodontitis to serum lipids/lipoproteins. Increases in serum endotoxin (e.g. LPS) during ligature-induced periodontitis were observed in these animals. We determined serum levels of various acute phase reactants and chemokines (e.g. CRP, alpha 1-antitrypsin, haptoglobin, fibrinogen, IL-8). A number of these host factors were significantly increased during gingivitis and/or periodontitis. Finally, we observed specific changes in serum lipid levels (cholesterol, triglycerides, HDL, LDL) and lipoproteins (apoA-I) during periodontitis, which were exacerbated by exposure of the animals to a diet with elevated fat content. Thus, we have described systemic manifestations of periodontitis that include detection of bacterial products, inflammatory biomarkers, and dyslipoproteinemia consistent with an increased atherogenic risk.     

Gingivitis as a risk factor in periodontal disease

Background: Dental plaque has been proven to initiate and promote gingival inflammation. Histologically, various stages of gingivitis may be characterized prior to progression of a lesion to periodontitis. Clinically, gingivitis is well recognized.
Material & Methods: Longitudinal studies on a patient cohort of 565 middle class Norwegian males have been performed over a 26-year period to reveal the natural history of initial periodontitis in dental-minded subjects between 16 and 34 years of age at the beginning of the study.
Results: Sites with consistent bleeding (GI=2) had 70% more attachment loss than sites that were consistenly non-inflamed (GI=0). Teeth with sites that were consistently non-inflamed had a 50-year survival rate of 99.5%, while teeth with consistently inflamed gingivae yielded a 50-year survival rate of 63.4%.
Conclusion: Based on this longitudinal study on the natural history of periodontitis in a dentally well-maintained male population it can be concluded that persistent gingivitis represents a risk factor for periodontal attachment loss and for tooth loss.     

龋齿、牙周炎患牙和健康牙的菌斑生物膜特征

目的研究牙面菌斑生物膜特征与口腔疾病的关系。方法选择牙周健康而牙冠严重龋坏的龋齿5颗、无龋损而极度松动的牙周炎患牙6颗及正畸原因拔除的健康牙4颗,在扫描电镜下,观察分析龈上、龈下及移行生态区的菌斑生物膜特征。结果龋齿、牙周炎患牙和健康牙的牙面均观察到细菌混合物组成的菌斑生物膜,健康牙菌斑生物膜以球菌为主,放线菌和短杆菌少量;龋齿牙的龋坏处为坏死组织和细菌,龋边缘及龈沟处的球菌和短杆菌较健康牙多;牙周炎患者牙菌斑生物膜的细菌种类多,在龈上、龈下移行处可见典型的玉米棒状菌斑或以杆菌为主的紧密附着菌斑,龈下可见球菌、杆菌、梭菌及螺旋体等构成的复杂菌斑。结论龋齿、牙周炎患牙和健康牙菌斑生物膜细菌组成、集聚秩序和立体结构不同,菌斑生物膜的形成与细菌的附着、集聚、生长有关,也与局部病变密切相关。     

Cell-mediated immunity in juvenile periodontitis and levamisole treatment.

Immunostimulation with levamisole was attempted in eight patients with juvenile periodontitis and six reference patients with gingivitis but without loss of periodontal attachment. The following parameters were studied before and after levamisole treatment: gingival status, the concentration of serum immunoglobulins and complement, T and B lymphocyte ratio, leukocyte migration inhibition and lymphocyte transformation responses by dental plaque bacteria, PPD or PHA, and lymphocyte ATP-ase activity. In juvenile periodontitis cell-mediated immunity to dental plaque antigens seemed to be impaired, but the response was not restored by treatment with levamisole. There was no evidence of a broader suppression of cell-mediated immunity in juvenile periodontitis and there was no significant clinical effect of levamisole treatment. It is suggested that the apparent suppression of in vitro cell-mediated immunity to dental plaque bacteria in juvenile periodontitis is a secondary change, caused by a long-standing chronic infection.     

Selective modulation of bacterial attachment to oral epithelial cells by enzyme activities associated with poor oral hygiene

The present investigation explored the hypothesis that elevated levels of certain enzymes in the gingival crevicular environment of individuals with poor oral hygiene and/or gingival inflammation may modify the surfaces of epithelial cells and thereby modulate the types of bacteria which attach and colonize. Buccal epithelial cells treated with neuraminidase and certain proteases were used as a model for study. Bacteria studied included Streptococcus sanguis and Streptococcus mitis which have been associated with gingival health, Actinomyces species which are increased in plaque associated with developing gingivitis, and Bacteroides gingivalis, Bacteroides intermedius, and Actinobacillus actinomycetemcomitans which are associated with destructive periodontal diseases. Treatment of epithelial cells with the enzymes studied produced selective effects on their receptivity for bacteria. Neuraminidase treatment of epithelial cells greatly reduced the attachment of all strains of S. sanguis and S. mitis studied. In contrast, the number of Actinomyces viscosus, A. naeslundii and A. israelii cells which attached was significantly increased. Neuraminidase treatment also appeared to enhance attachment of B. intermedius and B. gingivalis. Treatment of buccal cells with trypsin, chymotrypsin or papain also selectively affected bacterial attachment. Such protease treatment greatly reduced the numbers of streptococci and A. viscosus cells which attached, while the numbers of B. gingivalis and B. intermedius were significantly increased. Treatment of epithelial cells with preparations of lysosomal enzymes derived from human PMNs produced similar selective effects. The changes in bacterial adhesion observed by the enzyme treatments studied are consistent with the shifts in the composition of the gingival crevice flora which occur when oral hygiene is terminated and gingivitis develops.     

Cell-mediated immunity in juvenile periodontitis and levamisole treatment

abstract — Immunostimulation with levamisole was attempted in eight patients with juvenile periodontitis and six reference patients with gingivitis but without loss of periodontal attachment. The following parameters were studied before and after levamisole treatment: gingival status, the concentration of serum immunoglobulins and complement, T and B lymphocyte ratio, leukocyte migration inhibition and lymphocyte transformation responses by dental plaque bacteria, PPD or PHA, and lymphocyte ATP-ase activity. In juvenile periodontitis cell-mediated immunity to dental plaque antigens seemed to be impaired, but the response was not restored by treatment with levamisole. There was no evidence of a broader suppression of cell-mediated immunity in juvenile periodontitis and there was no significant clinical effect of levamisole treatment. It is suggested that the apparent suppression of in vitro cell-mediated immunity to dental plaque bacteria in juvenile periodontitis is a secondary change, caused by a long-standing chronic infection.     

Association of uncultivated oral phylotypes AU126 and X112 with periodontitis

OBJECTIVE: To discuss the relationship between uncultivated pathogenic bacteria and periodontitis. SUBJECTS AND METHODS: Specific polymerase chain reaction (PCR) primers were designed for phylotypes AU126 and X112; PCRs were applied to determine the prevalence of these phylotypes in 35 patients with chronic periodontitis, 26 patients with plaque-induced gingivitis and 20 healthy control subjects. RESULTS: The specificity of each primer is validated on the basis of the results from sequence analysis of PCR products. AU126 and X112 were detected in the subgingival plaque samples in all the three groups. The prevalence of AU126 in subgingival plaque in chronic periodontitis (77.1%) and plaque-induced gingivitis (61.5%) is relatively higher than that in the healthy subjects (10.0%), and the difference is statistically significant (P < 0.01). The prevalence of X112 in subgingival plaque in periodontitis patients (85.7%) is higher than that in healthy subjects (30.0%), the difference (P < 0.01) being equally statistically significant. The difference between the chronic periodontitis group and the plaque-induced gingivitis group (50.0%) is statistically significant (P < 0.05). CONCLUSIONS: It might be assumed that the novel uncultivated AU126 phylotype could possibly be related to chronic periodontitis and plaque-induced gingivitis, and that X112 might play a role in the progress of lesion from gingivitis to periodontitis.     

Two-dimensional gel electrophoresis of dog crevicular fluid proteins

The ligature-induced periodontitis model was used in beagle dogs to compare and contrast profiles of crevicular fluid (CF) proteins collected from gingivitis and periodontitis sites. The protein profiles of CF and serum were determined by 2-dimensional gel electrophoresis (2-D PAGE) using a silver stain. 2-D PAGE showed that CF contained proteins with molecular weight 16 K or less and many proteins with molecular weights between 64 K and 16 K in the isoelectric pH between approximately 5.8 and 6.8. The number of such proteins was greater in samples collected from the ligated (periodontitis) side compared to the non-ligated (gingivitis) side. Thus, analysis by 2-D PAGE revealed differences between CF samples from gingivitis and ligature-induced periodontitis sites. This study suggests that analysis of human CF by 2-D PAGE may be useful in diagnosis and investigation of the pathogenesis of periodontitis.     

Differences between gingivitis and periodontitis associated microbial flora in the beagle dog

The predominant dental plaque flora was compared between two groups of adult beagle dogs, (1) ten with gingivitis and (2) ten with advanced periodontitis. Plaque from a maxillary third premolar was cultured under strict anaerobic conditions. Specimens comprising the marginal periodontal tissues were taken at the plaque sampling site and analyzed for some histological parameters of periodontal disease. The periodontitis dogs scored significantly higher for crevice depth, length of ulcerated crevice epithelium, area of inflamed connective tissue, and loss of attachment. Supragingival periodontitis plaque had significantly higher anaerobic to aerobic ratio, proportions and CFU of esculin negative streptococci, but lower proportions of Actinomyces viscosus . Subgingival periodontitis plaque had significantly higher anaerobic to aerobic ratio, microscopic counts of spirochetes, total viable CFU, proportions and CFU of esculin negative streptococci and Fusobacterium nucieatum , as well as CPU of Bacteroides asaccharolyticus , Gram negative bacilli and coccobacilli, but significantly lower proportions of A. viscosus and unspeciated actinomycetes. The total viable CFU, proportions and CFU of esculin negative streptococci correlated with all four histological parameters of periodontal disease. The CFU of B. asaccharolyticus , bacilli, and coccobacilli correlated with the length of ulcerated crevice epithelium and loss of attachment, but F. nucleatum only with the area of inflamed connective tissue and loss of attachment.     

Microbiological and clinical effects of a dentifrice containing zinc citrate and Triclosan in the human experimental gingivitis model

A partial mouth experimental gingivitis model was employed to establish the effect of a dentifrice containing 0.2% Triclosan and 0.5% zinc citrate on the development of chronic gingivitis. In addition, changes in the plaque flora associated with the developing gingivitis have been monitored. Following a period of stringent oral hygiene, volunteers were allocated to 1 of 2 treatment groups. A toothshield was constructed to fit 4 posterior mandibular teeth. During the 21-day experimental period test or placebo dentifrice was applied to the experimental teeth via the tooth shield. The toothshield also prevented plaque removal from those teeth during habitual brushing of the remaining dentition. Supragingival plaque was collected at baseline and day 21 for analysis of the total bacterial flora. At the end of the experimental period, plaque and gingivitis had developed in both groups. However, the test group had significantly less plaque and gingivitis than the placebo group. The microbiological data demonstrated that plaque from the test group contained significantly lower numbers of anaerobes compared to plaque from the placebo group. This was considered particularly significant as these bacteria are generally associated with chronic inflammatory periodontal disease. There was also a trend for the numbers of actinomyces to decrease in plaque from the test group but not in the placebo group.     

Gingivitis

Gingivitis is caused by substances derived from microbial plaque accumulating at or near the gingival sulcus; all other suspected local and systemic etiologic factors either enhance plaque accumulation or retention, or enhance the susceptibility of the gingival tissue to microbial attack. Microbial species specifically associated with gingival health include Streptococcus sanguis 1, S. D-7, and Fusobacterium naviforme. Bacteria involved in the etiology of gingivitis include specific species of Streptococcus, Fusobacterium, Actinomyces, Veillonella, and Treponema and possibly Bacteroides, Capnocytophaga, and Eikenella. Microbial colonization and participation is sequential, with the complexity of the associated flora increasing with time. The pathogenesis has been separated into the initial, early, and established stages, each with characteristic features. The initial lesion is an acute inflammation which can be induced experimentally by application of extracts of plaque bacteria to normal gingiva. The early lesion is characterized by a lymphoid cell infiltrate predominated by T lymphocytes, characteristic of lesions seen at sites of cell-mediated hypersensitivity reactions. The early lesion can be induced by application of purified contact antigens to the gingival tissues of previously sensitized animals. As the clinical condition worsens, the established lesion appears, predominated by B lymphocytes and plasma cells. Established lesions may remain stable for indefinite periods of time, they may revert, or they may progress. Periodontal destruction does not result from the conversion of a predominantly T cell to a predominantly B cell lesion as has been suggested, but rather from episodes of acute inflammation. Clinical manifestations of gingivitis are episodic phenomena characterized by discontinuous bursts of acute inflammation. Most lesions are transient or persistent but not progressive. Attachment loss may precede alveolar bone loss and may occur without the manifestations of a concurrent or a precursor gingivitis. On the other hand, the evidence indicates that a portion of gingivitis lesions can and does progress to periodontitis. Gingivitis and the periodontal microflora differ in children and adults. Clinical signs of gingivitis either do not appear as plaque accumulates, or they are greatly delayed in children, and the inflammatory infiltrate consists mostly of T lymphocytes. The conversion to a B cell lesion does not appear to occur. The evidence supports the conclusion that gingivitis is a disease, and that control and prevention is a worthwhile goal and a health benefit.(ABSTRACT TRUNCATED AT 400 WORDS)     

Distribution of certain subgingival microbial species in selected periodontal conditions

Nine commonly encountered subgingival species were enumerated in subgingival plaque samples from periodontally healthy, gingivitis, and adult and juvenile periodontitis subjects employing two elective and three selective media. Samples were also obtained for darkfield microscopy. Results indicated that Eikenella corrodens and Fusobacterium nucleatum were usually elevated in proportions in sites with gingivitis or destructive periodontal disease. Capnocytophaga gingivalis was associated with gingivitis whereas Capnocytophaga ochracea was found in higher proportions in subgingival plaques of subjects with juvenile periodontitis. Previous association of Actinobacillus actinomycetemcomitans with juvenile periodontitis was confirmed. Spirochetes and other motile organisms were found more frequently and in higher proportions in the three disease states and were very strongly correlated with pocket depth. Motile organisms were also positively correlated with levels of plaque and redness in contrast to cocci which showed a strong negative correlation with all clinical parameters recorded.     

Susceptibility to gingivitis: a way to predict periodontal disease?

Clinical studies suggest that gingival inflammatory response to plaque accumulation may vary between individuals. Evidence seems to indicate that there is an association between susceptibility to gingivitis and susceptibility to periodontitis. Recently, among participants in a large scale experimental gingivitis trial, we were able to identify and characterize subjects that differ significantly in their gingival inflammatory response to plaque accumulation. Research efforts are being focused on the effect of genetic, anatomic and environmental host-related factors which may be implicated in the pathogenesis of the gingival inflammatory process, and whether susceptibility to periodontitis and susceptibility to gingivitis may partly share common risk factors. In this respect, it is possible that identification of factors related to increased susceptibility to gingivitis may help identify, at an early age, subjects at risk of periodontitis.     

Rapidly progressive periodontitis combined with plasma cell gingivitis: a case report

A case of rapidly progressive periodontitis combined with plasma cell gingivitis with marked enlargement of the gingiva was presented. Clinically, in the plasma cell gingivitis, the gingiva appear red, friable and bleed easily; usually it does not induce loss of attachment. Histologically, a dense infiltration of the normal plasma cells in the connective tissue is a common finding. A hypersensitivity reaction to some antigens, often flavorings or spices, is generally recognized. In this case, a rapidly progressive loss of attachment was observed, so rapidly progressive periodontitis was diagnosed. Differential diagnosis of the plasma cell gingivitis could be determined by histological and ultrastructural examination. Allergens, however, could not be identified. Conventional periodontal therapy, including intensive plaque control, could not cure the plasma cell gingivitis completely but recurrence of gingival enlargement and loss of attachment could be well controlled.