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151.
The etiology of a form of periodontal disease in domestic cats known as plasma cell gingivitis-pharyngitis is not understood. Actinobacillus actinomycetemcomitans and Bacteroides species have been strongly implicated as the cause of periodontitis in humans and other mammalian species, and most affected patients manifest serum antibodies reactive with the infecting bacteria. We and others have isolated Bacteroides species from the oral flora of cats. Using enzyme-linked immunosorbent assay (ELISA) and immunoblot procedures, we measured serum antibodies in affected and control cats reactive with human isolates of A. actinomycetemcomitans, B. gingivalis, and B. intermedius, and purified lipopolysaccharide (LPS) from these and other species, and Bacteroides of cat origin. Affected cats had serum antibody titers reactive with these Gram-negative anaerobic bacteria that were significantly elevated relative to those of normal control cats. The quantitatively major antigens recognized by cat serum antibodies are proteins; this contrasts sharply with serum antibodies from humans with juvenile periodontitis, where LPS is the quantitatively major antigen fraction. Our data support the idea that plasma cell gingivitis-pharyngitis in cats may have a bacterial etiology, and that Gram-negative anaerobes similar to those that cause periodontitis in humans and other mammals may be involved.  相似文献   
152.
Angiolipoma of the tongue: report of a case   总被引:1,自引:0,他引:1  
Angiolipoma is a rare variety of lipoma in the maxillofacial region. Only eight cases have been documented so far. A case in which an angiolipoma occurred within the tongue of a 49-year-old man is described here. The difference from earlier cases occurring in the tongue is noted. Close follow-up has, as yet, revealed no recurrence.  相似文献   
153.
The purpose of this investigation was to evaluate the histologic response to replamineform (porous) hydroxyapatite grafts in chronically inflamed, surgically created, periodontal pockets in Rhesus monkeys. Forty-eight subcrestal defects were surgically created in 8 Rhesus monkeys. Orthodontic wires were adapted to the base of the defects and left in place for 8 weeks. The defects were randomly assigned a treatment modality so that 8 granular porous and 8 block porous hydroxyapatite grafts were done. Eight sites were left as unoperated controls. Twenty-four contralateral sham-operated sites were treated by open curettage. Histometric measurements of the length of regenerated connective tissue attachment were recorded. Block hydroxyapatite, granular hydroxyapatite, and sham-operated sites exhibited similar amounts of regenerated connective tissue attachment, which was significantly greater than that which occurred in unoperated controls. Newly formed bone was observed within the porous channels of the hydroxyapatite grafts as well as in direct apposition on the surface of implant particles. New bone, cementum, and periodontal ligament was observed in grafted sites and in defects treated by open curettage. In some instances healing occurred by means of a long junctional epithelium. Histology confirmed that unoperated defects remained as unhealed, inflamed periodontal pockets. The results of this study suggest that porous hydroxyapatite grafts have the potential to regenerate the attachment apparatus in primates.  相似文献   
154.
The relationship between oxide adherence and porcelain-metal bonding   总被引:4,自引:0,他引:4  
The lack of a reliable bond test has hindered the elucidation of the mechanism for porcelain-metal bonding in dental systems, because a test capable of detecting differences among porcelain-metal bonds of various qualities is required before the reasons for these differences may be ascertained. A method was developed in the present study whereby specimens of alloys with differing physical properties may be deformed to a constant strain to yield a fracture surface suitable for measurement of the area fraction of retained porcelain by an x-ray spectrometric technique described previously. The method proved sufficiently discriminating that significant differences could be found in 48 of the possible 66 comparisons among alloys and treatments. Linear regression analysis revealed a strong correlation (r2 = 0.947) between the area fractions of retained porcelain measured in the present study and the oxide adherence strength values measured previously. This strong correlation, when considered in light of the literature evidence for the presence of an oxide layer at the porcelain-metal interface, provides compelling support for the oxide layer theory of porcelain-metal bonding in dental alloy systems.  相似文献   
155.
Oral examinations were performed on 5 patients with hypophosphatemic bone disease (HBD) (2 males and 3 females), 14 patients with X-linked hypophosphatemia (XLH), and 4 affected XLH relatives (6 males and 12 females). The control subjects were the unaffected siblings and parents of the patients and unrelated healthy, gender- and age-matched subjects. Serum phosphorus values were the same by disease type and gender in patients with HBD and XLH. They shared certain dental abnormalities, in particular pulpal necrosis and large pulp spaces. However, only patients with XLH had Class III malocclusions and mild enamel defects, and males with XLH had more severe occlusal and enamel defects than females with XLH. Different dental phenotypes are further evidence that XLH and HBD are different diseases. The dental abnormalities were not prevented by treatment, instituted early in life, which raised serum phosphorus to the near normal range.  相似文献   
156.
157.
The expression of cytokeratin (40-52 kD), carcinoembryonic antigen (CEA), vimentin, neuron-specific enolase (NSE), S-100 protein, glial fibrillary acidic protein (GFAP) were investigated in 20 cases of pleomorphic adenoma of the salivary glands and 10 cases of normal salivary glands, in order to analyze and correlate the antigens' expressions with the probably histogenetic mechanisms of the various histopathological differentiations in pleomorphic adenoma of the salivary glands and their probably original cells in normal salivary glands. Immunohistochemistry has provided some evidence for the relationship of the tumor cells to normal salivary glands: In the normal glands, the acinic cells exhibited cytokeratin, CEA and focal, predominantly nuclear S-100 protein staining. In both normal glands and pleomorphic adenomas, the duct-lining cells were immunoreactive for cytokeratin, CEA and had both cytoplasmic and nuclear S-100 positivity; The myoepithelial cells of the normal glands as well as the periduct cells, epithelial nests/cords, squamous metaplasia and the stellate/spindle/cartilaginous cells in the myxomatous-chondroid areas of the pleomorphic adenoma contain immunoreactive vimentin, NSE, S-100 proteins and GFAP, and lesser amounts cytokeratin (40-52 kD)/CEA. The varicosities of the terminal axon may lie directly on the basal membrane, or penetrate the basal membrane and lie in direct contact with the effector cells (duct-acinar-myoepithelial cells) of the salivary glands. The peripheral neurons and axons of the autonomic nervous system were identified by vimentin, NSE, S-100 proteins and GFAP. The combination of epithelial cytokeratin and nervous system-related vimentin, NSE, S-100 and GFAP immunostaining in myoepithelium of the normal glands and in all component elements (particularly the periduct cells) of pleomorphic adenoma reflects pleomorphic adenoma of the salivary glands is an epithelial tumor, the probably original cells or the probably histogenetic mechanisms of the various histopathological differentiations is correlated not only with "duct-acinar-myoepithelial cells" but also with the neuroectoderm in the normal salivary glands."  相似文献   
158.
159.
Cigarette smoking is a major risk factor in the development and further progression of periodontitis. However, little is known regarding the pathogenesis of smoking-related periodontal diseases. The purpose of this study was to examine the effects of nicotine, alone and in combination with lipopolysaccharide (LPS), on monocyte secretion of bone-resorbing factors, PGE2 and IL-1β. Peripheral blood monocytes (PBM) were isolated by counterflow centrifugal elutriation from 15 healthy, non-smoking donors. PBM were incubated for 24 h in RPMI 1640 containing nicotine (0, 50 μg/ml, I μg/ml, 10 μg/ml and 100 μg/ml) with or without 10 μg/ml Porphyromonas gingivalis LPS or Escherichia coli LPS. Culture supernatants were assayed for PGE2 and IL-1β by ELISA. None of the nicotine preparations resulted in significant PBM secretion of PGE2 and IL-1β above that of unstimulated cultures. However, PGE2 release was potentiated 1.7-fold by the combination of P. gingivalis LPS and 10 μg/ml nicotine relative to P. gingivalis LPS alone (p<0.05, one-way ANOVA). Prostaglandin E3 release also was potentiated 3.5-fold by P. gingivalis LPS and 100 μg/ml nicotine relative to P. gingivalis LPS alone (p<0.00001, one-way ANOVA) and 3.1-fold by E. coli LPS and 100 μg/ml nicotine relative to E. coli LPS alone (p<0.00001, I. one-way ANOVA). IL-1β secretion was lower for either LPS plus 100 μg/ml nicotine relative to LPS alone, although not significantly. These data demonstrate upregulation of LPS-mediated monocyte secretion of PGE2 by nicotine and suggest a potential role for nicotine in periodontal disease pathogenesis.  相似文献   
160.
Toothbrushing force in relation to plaque removal   总被引:1,自引:0,他引:1  
Abstract This was a 2-part study. The purpose of the 1st part was to examine the relationship between brushing force and plaque removal efficacy comparing a regular manual toothbrush (M) with an electric toothbrush the Braun Oral-B Plak Control* (B). The study consisted of a single oral prophylaxis followed by 5 experiments which differed solely in respect to toothbrushing force. At baseline (after 24-h plaque accumulation), the amount of dental plaque was evaluated and subsequently, the subject's mouth was brushed by a dental hygienist. Brushing was carried out in a random split-mouth order. Either the 1st and 3rd quadrants or the 2nd and 4th quadrants were brushed with 1 toothbrush and the 2 remaining quadrants with the other. The available time for the brushing procedure was 2 min. After brushing, the amount of remaining dental plaque was assessed. The force used in experiment 1 through 5 was 100, 150, 200, 250, 300 g, respectively. The results show that when brushing force is increased, more plaque is removed with either of the two brushes. Except for the high brushing force (300 g), the electric toothbrush removed more plaque than the manual brush. The purpose of the 2nd part was to evaluate the habitual brushing force which individuals use with various toothbrushes. Besides a manual toothbrush (M), 3 electric toothbrushes were examined, the Rotadent® (R). Interplak® (I) and Braun® (B). 20 subjects were selected on the basis of being ‘good brushers” (plaque score at screening <25%). At baseline, each subject randomly received 1 of the 4 brushes. They were allowed a training period of 3 weeks at the end of which they were asked to abstain from brushing for at least 24 h. The plaque (Turesky modification of the Quigley & Hein) was scored, after which the subjects brushed their teeth (2 min) with the assigned toothbrush equipped with a strain gauge. A computer set–up measured (100 Hz) and calculated the mean brushing force. After brushing, the amount of remaining plaque was assessed. The design of the study was a 4-way cross-over. The results show that with a manual brush, considerably more force is used than with the electric brushes (R=96. 1 = 119. B= 146, M=273). No significant relation between brushing force and plaque removal was demonstrated for any of the brushes.  相似文献   
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