Showing papers in "Journal of Oral Pathology & Medicine in 1975"

The pathogenesis of odontogenic cysts: a review

Abstract: The pathogenesis of the three common forms of odontogenic cyst is discussed. It is concluded that the dental cyst arises from proliferation of the epithelial rests of Malassez in a focus of inflammation stimulated by pulpal necrosis of the associated tooth. It enlarges by unicentric expansion from the hydrostatis pressure of its contents. The dentigerous cyst arises from pooling of inflammatory exudate, which is derived from the obstructed follicular veins of an unerupted tooth and accumulates between the reduced enamel epithelium and the crown of the tooth. It enlarges by unicentric expansion from the hydrostatic pressure of its contents. The odontogenic keratocyst arises by proliferation of the residues of the dental lamina, possibly as a hamartomatous abnormality. It enlarges by both multicentric expansion due to the proliferation of localized groups of epithelial cells in the lining and by unicentric expansion from the hydrostatic pressure of its contents.

The reaction of salivary substances with bacteria

Abstract: . Reactions between selected strains of oral streptococci and saliva were studied spectrophotometrically. The curves of absorbance (700 nm) versus those of time were sigmoidal for aggregating saliva-bacteria mixtures. When the logarithm of the ratio of the change in absorbance to the remaining absorbance was plotted against the reaction time, straight lines were obtained. At a fixed concentration of bacteria, the slope of these lines for a series of dilutions of a selected saliva sample was a parabolic function of the volume of saliva in the reaction mixtures. A model for the aggregation reaction was developed which explained the shape of these parabolic curves. The parameters of the model can be calculated from the experimental data and can be used to estimate the concentration of aggregation-inducing substances in undiluted saliva. A method for calculating the specific rate constant for the binding of free cells to aggregates was developed. This rate constant is a characteristic feature of a given aggregation reaction and can, in principle, be used to distinguish between aggregation-inducing substances of different molecular structures.

Ghost cell epithelium in odontomas.

Abstract: Eight cases from a series of 75 odontomas were found to contain ghost cell epithelium. Clinical, radiologic and histologic findings in these cases did not differ significantly from those of odontomas in general. The results obtained with several staining methods, including rhodamin B under fluorescent light, suggest that the ghost cells represent different stages in the process of ortho-, para- and aberrant keratin formation. Ghost cells should be viewed as the product of metaplastic transformation of the odontogenic epithelium with no significance for the prognosis and treatment of odontomas.

The histology of prolonged candidal infection of the rat's tongue

Abstract: . Long-term candidal infection of the rat's tongue has been found to produce marked epithelial hyperplasia with keratin trapped between the folds of hyperplastic epithelium. The epithelium showed atypia which did not amount to carcinoma in situ. Degenerative changes were found in the superficial layers of the lingual muscle beneath areas of candidal infection, and after a year, hyalinized fibrous tissue appeared to replace the damaged muscle.

Morphology of salivary calculi. The distribution of the inorganic component.

Abstract: . Different hypotheses concerning the pathogenesis of salivary calculi have been postulated on the basis of their morphology. In the present study, microradiography of plane-polished ground sections of a number of salivary calculi has shown that the morphology of salivary calculi varies considerably. The commonly accepted concept that salivary calculi emanate from an inorganic nucleus, which then successively grows by the apposition of alternating shells of organic and inorganic substances, could not be established by this study, as the microradiographs show that the distribution of mineral elements varied extensively from one calculus to another. Thus, whereas some calculi exhibited a lamellar structure, others consisted largely of homogeneous, irregular layers of alternatively high and low mineral content. The lamellar structure also showed great variation, extending in some cases over the entire diameter of the calculus. Some calculi lacked the lamination in their peripheral parts whereas, in others, lamination occurred only in the most peripheral zone. The structure of the central portions also showed a varied configuration. The calculi were often built up around one or more mineralized nuclei, often centrally located, while in some cases a mineralized nucleus was lacking. This report discusses some of the significant factors in the great variation in morphological features and therefore also in the pathogenesis of salivary calculi.

Crystalline structure of salivary calculi

Abstract: . The crystalline substances localized in different areas of salivary calculi were identified by using microradiographic and X-ray microdiffractometric techniques. All 19 calculi analyzed had a general pattern of apatite which was recognizable both in the center and at varying distances from the core. In addition to apatite patterns, six of the calculi gave a diffraction pattern of whitlockite, which in all but one case was located in the central part of the calculi. The influence of various factors on the distribution of the crystalline substances of apatite and whitlockite within the calculi is discussed.

Experimental salivary mucoceles in cat. A histochemical study.

Abstract: Ductal ligation of the sublingual gland induced mucocele formation in a high percentage of cats. Extravasated mucus was associated with all sublingual glands up to 20 days after ligation, and extravasation mucoceles were associated with 12 out of 27 sublingual glands between 7 and 365 days after ligation. Enzyme-histochemic examination revealed that the extravasated mucus induced a migration of macrophages and a fibroblastic reaction. It is thought that if these reactions are sufficiently intense in the early days after ligation, then continued spread of extravasated mucus and mucocele formation does not occur; however, if the extravasation is too great to be contained, a mucocele forms in which a balance develops between extravasation of mucus and its removal. Possibly the numerous macrophages in the mucoceles are involved in degrading mucus and facilitating its removal.

A qualitative and quantitative electronmicroscopic study of the structure of the adenoid cystic carcinoma of human minor salivary glands

Abstract: The fine structural characteristics of five adenoid cystic carcinomas of human minor salivary galnds and a quantitative assessment of the relative volumes occupied by morphologically defined cell types in these tumors are reported. We observed that the cyst-like spaces which give the characteristic cribriform pattern to the adenoid cystic carcinoma contain replicated basement membrane-like materail. Material comprisimg aggregates of fine tubules having a median diameter of 270 A, and rounded, electron dense bodies were noted within duct-like lumena of one tumor. In addition, dilatation of the intercellular spaces and squamous metaplasia were noted. From 500 electronmicrographs obtained by standardized techniques and used for the morphological part of the study, 175 were selected by a random sampling method and analyzed by the stereological technique of point counting. This method demonstrated that duct type cells occupied 75% by volume of the tumor in these glands; myoepithelial cells occupied 3%, acinar cells occupied 2%, and other tissues occupied 22% of the tumors. These proportions differ significantly (P less than 0.001) from our previously published figures for normal specimens of these glands.

Ultrastructural aspects of chronic oral candidosis

Abstract: . Human biopsy specimens from white patches on the mucosae of tongue and lips which had previously given positive cultures for Candida albicans were examined. The specimens were processed for electron microscopy by conventional techniques. The fine structure of the superficial layer of the epithelium revealed Candida albicans in extra- and intracellular sites. Penetration into the deeper layers was not observed. The fungus had a thick cell wall surrounded by an outer floccular layer. The cytoplasm of the superficial epithelial cells showed degenerative changes and fragmentation of tonofilaments in the immediate vicinity of the fungus. Microabscesses, formed by pools of neutrophils, were common in the upper spinous layer. In places, fungi and bacteria appear to have been phagocytosed by neutrophils and macrophages. The cells of the lower spinous and basal layers showed detachment of desmosomes, marked increase in intracellular glycogen, prominent lysosome-like dense bodies and abundant mitochondria of differing shapes. At the epithelial-connective tissue junction, fine filaments and collagen fibrils were intermingled throughout the basal lamina, forming multiple, highly electron-dense layers. A noticeable change in the connective tissue was the accumulation of numerous mast cells containing differently shaped granules filled with scrolls and dense strands of granular material. The terminal blood vessel exhibited leakage and numerous, concentric duplications of the basal lamina.

Enzyme histochemical studies on the formation of hyalin bodies in the epithelium of odontogenic cysts.

Abstract: Frozen sections of eight odontogenic cysts, including one keratocyst, were incubated to show the following enzyme activities: NADH2 diaphorase, NADPH2 diaphorase, glucose-6-phosphate dehydrogenase, acid phosphatase and leucine aminopeptidase. The disbribution of lipid was shown by the oil red 0 method. The activities of all three oxidative enzymes were strongest in epithelial cells bordering hyalin bodies and in basal cells in the epithelial lining. Hydrolytic enzyme activity was absent from all but the most superficial epithelial cells but was present in macrophages and, in lesser amounts, in granular material in the same sections. The granular material frequently contained lipid. The lack of hydrolytic enzyme activity in bordering epithelial cells is inconsistent with the theory that hyalin bodies form from degenerating blood vessels. High aerobic oxidative enzyme activity in the same cells also conflicts with the concept that the bodies are a keratinous product. The findings lend support to the theory that hyalin bodies are an epithelial secretion.

Studies on human dental plaque. 2. Immunochemical characteristics.

Abstract: From collected supragingival plaque, extracts were prepared for immunochemical analyses. Extracted sediments were examined by fluorescein-labeled antibodies for the presence of immunoglobulins. Precipitation with monospecific and polyvalent antisera revealed IgA, IgG, secretory component, C3, alpha2macroglobulin, lactoferrin, and albumin in the extracts. Gel filtration of pooled plaque extract yielded two fractions that contained the aforementioned proteins and a prominent, dialyzable third fraction that was immunochemically nonreactive. IgA, IgG, secretory component, and light chains were shown, by immunofluorescence, to be present in washed, pooled plaque sediment. Release of these immunoglobulins by urea treatment indicated their probable participation in immune complexes.

Studies on human dental plaque. 1. Physical and chemical characteristics and enzyme activities of pooled plaque extracts.

Abstract: . Human supragingival dental plaque was collected from patients with various degrees of caries and periodontal disease. Plaque extracts, prepared in five different solutions (four varied from pH 1.8 to 12.7; one contained urea), were analyzed by polyacrylamide gel electrophoresis, and tested for amylase and lysozyme enzyme activity. Because no qualitative or quantitative advantages of using the extremes of pH or urea were observed, all subsequent extracts were prepared in phosphate buffered saline at pH 7.3. Concentrated extracts were fractionated by gel filtration and characterized by polyacrylamide gel electrophoresis, peptide mapping, molecular weight estimation, determination of enzymatic activities and amino acid and carbohydrate analyses. Regions of similarity among the gels were revealed by comparing the electrophoretic patterns of pooled plaque extract, normal serum and whole saliva. The elution pattern of pooled plaque extract from a standardized Sephadex G-200 column indicated the presence of both high and low molecular weight proteins that might have correlated with the components of normal serum and saliva. A predominant and dialyzable third fraction had no correlate in either serum or saliva. The small peptides in this fraction were subjected to amino acid, carbohydrate and peptide map analyses. The most abundant amino acids were alanine, glutamic acid, glycine, valine, leucine, lysine and serine. These small components contained no neutral or amino sugars. Pooled plaque extract and the small peptides exhibited similar peptide maps.

Ultrastructure of the oral epithelium in leukoplakia associated with tylosis and esophageal carcinoma.

Abstract: Ultrastructural studies have been carried out on epithelium taken from the oral lesions of tylosis-related leukoplakia and preleukoplakia in a group of patients known to be at high risk for esophageal carcinoma. Several structural abnormalities are described; in particular, the presence of intranuclear electron dense particles 90 nm in diameter. Similar particles have been found in the nuclei of epithelial cells from an esophageal carcinoma developing in one of the patients under study.

The nature of epithelial proliferation in apical granulomas.

Abstract: . Small sections of granulomas containing proliferating epithelium were incubated with a radio-opaque marker (Thorotrast®) and tissue culture medium. Electron microscopic examination demonstrated that some epithelial cells had the potential to take up the marker whereas in control sections of apical cysts this did not occur. The implications of these results are discussed.

Experimental allergic sialoadenitis. VII. Reactivity of the parotid gland to antigenic challenge in passively immunized rats.

Abstract: Rats were passively immunized by an intraperitoneal injection of homologous anti-BSA serum and their salivary glands were challenged 20 min or 24 hours later with BSA by the intraductal route. Immune complex sialoadenitis developed only when challenge was early. It is concluded that immunoglobulins are transferred from the circulation into the salivary glands and are relatively rapidly cleared by a mechanism yet unknown, possibly by salivary flow.

Lanthanum staining of cell surface and junctional complexes in normal and malignant human oral mucosa.

Abstract: Biopsies from normal and malignant human oral epithelium were studied electron histochemically using lanthanum nitrate for a selective demonstration of junctional complexes at the plasma membrane of adjacent cells. The heavy metal complex was found to settle irregularly, sometimes in intimate proximity to the epithelial cell, in areas corresponding to the glycocalyx, gap junctions, desmosomes and nonspecific contact areas. Tight junctions were rarely seen. The lack of these morphological adhesive areas, the desosomal detachment seen between cancer cells and the increased lanthanum-positive cell surface may be possible factors responsible for the dissociation of oral malignant cells.

Histochemistry of the keratohyalin granules in human oral leukoplakia

Abstract: The keratohyalin granules from 25 human oral leukoplakias, showing benign hyperorthokeratosis histologically, were examined employing a series of histochemical techniques. The tissues were fixed in 10% neutral buffered formalin, 80% methanol, or Carnoy's fluid. The keratohyalin granules stained intensely with Pauly's reagent, Congo red and Harris hematoxylin, indicating the presence of proteins. This was confirmed by abolishing the staining reaction by pretreatment with proteolytic enzymes. The keratohyalin granules also reacted with methyl green-pyronin by staining pink at their peripheries; this staining was abolished by pretreatment with ribonuclease, indicating the presence of ribo-nucleotides. The keratohyalin granules partially stained with toluidine blue and colloidal iron, indicating the presence of acidic polysaccharides. The keratohyalin granules did not react with the Feulgen reagent, suggesting the absence of DNA. Our studies indicate that the keratohyalin granules in human oral leukoplakia are primarily protein(s) complexed with polyribonucleotides. The presence of a carbohydrate moiety suggests the possibility of a protein-polysaccharide component in the granules.

Studies on human dental plaque. 3. Variation of protein constituents among individuals.

Abstract: . Separate plaque samples (collected from 13 patients who had experienced caries and various degrees of periodontal disease) were each dispersed in 1 ml of distilled water, homogenized and lyophilized. Each lyophilisate was extracted in 1 ml of buffered saline, concentrated and analyzed. Enzyme activity studies revealed amylase in all plaque samples. Lysozyme was present occasionally. By radial immunodiffusion, IgG and IgA were shown to be in plaque extracts of some patients. Immunofluorescence examination of the sediments of individual plaque samples revealed that IgG and IgA occurred frequently. Polyacrylamide gel electrophoresis patterns of the extracts of plaque from different individuals exhibited marked variability despite some zones of similarity. Peptide maps of the dialysable material of the individual plaque extracts were remarkably similar.

Cytological and histological keratinization studies in leukoplakias of the mouth.

Abstract: . A correlative histocytological study for keratinization was done in 446 cases of oral leukoplakia. Cytologically, keratinization could be correctly identified in 91 % of leukoplakias exhibiting orthokeratosis, 73 % of leukoplakias exhibiting parakeratosis, and 78 % of cases showing both types of keratinization. Cytologically, orthokeratosis was present in 83 % of individuals with homogeneous leukoplakia and in 69 % with ulcerated leukoplakia, while parakeratosis was present in 7 % of homogeneous leukoplakias and in 19 % of ulcerated leukoplakias. A higher frequency of dysplasia was observed in smears and their corresponding histological sections for those cases which had revealed only parakeratosis in the cytological examination and for both orthokeratosis and parakeratosis as compared to those showing only orthokeratosis. It is suggested that the cytological method is a reliable method for studying oral keratinization and is of value to the clinician in identifying the type of leukoplakias which may need to be biopsied for further surveillance.

A histological study of tooth allografts transplanted to untreated and immunologically prepared mice.

Abstract: . Ten-day-old mouse teeth were grafted subcutaneously into adults of an unrelated strain which were either untreated or had rejected a skin graft from the same strain as the tooth donors. First set allografts degenerated rapidly after grafting and were only sparsely repopulated subsequently. No cell-mediated Immune response was observed. In contrast, second set allografts were heavily infiltrated with mononuclear leukocytes which persisted throughout the study, although the coronal pulp was never involved. It was suggested that first set allografts did not suffer a cell-mediated response because rapid degeneration of the cellular components removed the immunogenic target tissue before the host response could be effected.

Cyclic AMP content of gingival fluid in women taking oral contraceptives.

Abstract: . Gingival fluid samples were collected from 12 healthy adult women who ranged in age from 19 to 34 years. Seven subjects with normal menstrual cycles who received no medications acted as controls while five subjects who had been using oral contraceptives for a minimum of 17 months constituted the experimental group. The women using birth control pills showed a 53% increase in the gingival fluid volume versus the controls. Radioimmunoassay revealed a mean concentration of cyclic adenosine monophosphate (cAMP) in the gingival fluid of 3.8.10−6 M in the controls and 1.9.10−6 M in subjects using oral contraceptives, although the total amount of cAMP present in the fluid from both groups was equal. These gingival fluid cAMP levels were a hundredfold higher than those measured in serum and saliva.

Ultrastructural observations of the oral mucosa in Anderson‐Fabry disease

Abstract: Electron microscopic study of oral mucosa from a patient with Anderson-Fabry disease (glycosphingolipid lipidosis) revealed lamellar and membranous osmiophilic intra-cytoplasmic inclusions having a periodicity of 45 nanometers These were observed chiefly in reticulo-endothelial cells as membrane bound and occasionally unbound bodies They could also be observed within the cytoplasm of squamous epithelial cells, particularly of the stratum germinativum Morphologic features in endothelial and epithelial cells are described

The fibrous epulis in the dog.

Abstract: The pathology of the fibrous epulis in the dog is described and found to be comparable to that seen in humans. Emphasis is placed on the apparent relationship between the hyperplasia of the covering epithelium and calcification of the connective tissue component, and a theory to explain this relationship is proposed.

Identification of hamster thymus-derived lymphocytes employing rabbit anti-hamster brain serum.

Abstract: . Rabbit anti-hamster brain sera prepared from the brains of Syrian and Chinese hamsters were evaluated for their potential to identify thymus-derived lymphocytes present in these animals. The unabsorbed antisera were cytotoxic in vitro for both homologous and heterologous thymocytes and splenocytes. Following absorption with hamster liver and erythrocytes, the antisera remained toxic for thymocytes, but were less toxic for splenocytes. Comparative testing of both the rabbit anti-Syrian and anti-Chinese brain sera with rabbit anti-C3H mouse brain serum indicated that considerable cross-reactivity exists between the different anti-brain sera. The in vivo administration of any of the antisera to C3H mice resulted in a lowered titer to the thymus-dependent sheep erythrocyte antigen response as measured by the hemolysis-in-gel technique. In vitro treatment with the anti-brain sera had no effect on plaque-forming cells present in the spleen.

Ultrastructural characteristics of mast cells from a canine mastocytoma maintained in vitro

Abstract: . Mast cells obtained from a canine mastocytoma were maintained in cell culture for a period of 11 weeks. Samples of these cells were harvested for electron microscopic examination after 9 weeks in vitro. Although the overall morphologic appearance was sufficient to allow their identification as mast cells, the tumor cells differed in several respects from descriptions of normal tissue mast cells. In contrast to normal tissue mast cells, the tumor cells exhibited peripheral accumulations of microfilaments, randomly dispersed microtubules, and small clusters of smooth endoplasmic reticulum. The tumor mast cells also presented three different granule types: spherical granules with an amorphous and electron dense matrix; irregularly shaped granules possessing a limiting external membrane and an internal matrix containing laminated and/or coiled structures; and granules containing loosely coiled, unorganized membrane structures similar in appearance to myelin whorls. The canine mastocytoma is an excellent source of mast cells as they can be obtained in large numbers without contamination by extraneous cell types and the cells can be maintained in vitro for extended periods of time.