Modifications of the dental pulp in marginal periodontitis. Electronomicroscopical contributions.

Histological studies on teeth with marginal periodontitis, but without cavity lesions have shown a frequent apparition of modifications in the pulp tissue structure. In this study, by using the electron microscopy method, we have shown a series of interesting aspects of the intimate modifications that appear on the level of all components of the pulp tissue. The observations show that the degree of affecting can be correlated to the type of marginal periodontitis, and at the same time they contribute to a right evaluation of the defensive abilities of the pulp of the teeth with marginal periodontitis.

Detection of plasma cell immunoglobulins in tissue sections optimally fixed for ultrastructural immunocytochemistry.

We describe the ultrastructural localization of plasma cell immunoglobulins in vibratome sections of popliteal lymph nodes. Fixation with glutaraldehyde-paraformaldehyde gave better tissue and antigen preservation than paraformaldehyde or periodic acid lysine-paraformaldehyde; biotinylated Fab fragments of sheep anti-mouse IgG-streptavidin-biotinylated horseradish peroxidase (HRP) or Fab-HRP conjugates gave similar results. With both immunoreagents, excellent tissue preservation and antigen detection was observed in the first layer of cells sectioned with the vibratome. Conjugates of anti-mouse IgG with HRP did not show any staining. Peroxidase stain was observed in the nuclear envelope, cisternae of the rough endoplasmic reticulum, and the Golgi apparatus complex. In the Golgi apparatus, staining was seen consistently in cisternae of the cis face and in adjacent vesicles; the trans cisternae showed weak or no stain, and adjacent vesicles, "coated" vesicles, and granules were not stained. This study shows that high quality of tissue preservation and antigen detection, by both light and ultrastructural immunocytochemistry, is feasible in tissue fixed with glutaraldehyde-paraformaldehyde followed by vibratome sectioning and immunostaining with Fab-biotin-streptavidin-biotin-HRP, or Fab-HRP.

The distribution of plasma cells in naturally occurring periodontitis lesions in rats. A light and electron microscopic study.

Plasma cells are widely distributed in inflamed periodontal tissues, the adjacent periodontal ligament and nearby alveolar bone spaces, of old rats (20 and 27 months) raised on a conventional diet in a normal laboratory environment. Electron microscopy revealed three morphologic types (or perhaps stages) of these cells based on the arrangement and content of the granular endoplasmic reticulum. Close contact between plasma cells and other cell types, such as lymphocytes, macrophages and fibroblasts, were commonly observed. It is suggested that plasma cell infiltration is a widespread and prominent feature of naturally occurring periodontitis in old rats, resembling the condition known to exist in humans, monkeys and dogs. The occurrence of large numbers of apparently fully differentiated plasma cells in otherwise normal alveolar bone marrow is discussed.

Histopathological and ultrastructural findings in a case of Papillon-Lefèvre syndrome.

Gingiva from a 3-year-old Iranian boy suffering from Papillon-Lefèvre syndrome was examined by light and electron microscopy. Deep pockets associated with predominantly Gram-negative plaque were present. The gingival lesion was dominated by plasma cells, many of which were degenerate. Russell bodies were a prominent feature. No defect of epithelium was detected.

Russell bodies in dental pulp of permanent human teeth.

OBJECTIVES: We sought to characterize the prevalence of Russell bodies in specimens clinically diagnosed as pulpitis. STUDY DESIGN: Forty-five teeth with symptomatic irreversible pulpitis were extracted, fixed, and demineralized. Five nonsymptomatic human teeth extracted for orthodontic purposes were used as controls. All teeth were then processed for light microscopy, for which they were stained variously, or for transmission electron microscopy (TEM). RESULTS: There was no evidence of Russell bodies in the pulp of 5 nonsymptomatic human teeth. Russell bodies, however, were detected in 31/45 (69%) of pulpitis specimens examined by light microscopy. The basic stains safranin and fucsin gave better visualisation of them than other staining procedures. All pulpitis specimens were histologically characterized as having the features of chronic inflammation. Of 5 specimens of pulpitis teeth evaluated by TEM, all exhibited Russell bodies. There was no morphological distinction among the Russell bodies when view either by light or electron microscopy. These structures appeared either within rough endoplasmic reticulum (RER) or they were found in extracellular stroma, suggesting their association with the lysis of cells. CONCLUSIONS: Russell bodies are prevalent in pulpitis samples with histological features of chronic inflammation, but are not found in all such samples. Russell bodies may not have been frequently detected in the past due to the types of stains employed in histolopathological study of pulps. The mechanistic basis of the association of Russell bodies with the symptoms of irreversible pulpitis is not clear.

Respiratory scleroma: a clinicopathologic and ultrastructural study.

Respiratory scleroma (rhinoscleroma) is a chronic granulomatous infection produced by Klebsiella rhinoscleromatis, a gram-negative aerobic coccobacillus. This disease is endemic to Africa, Central and South America, South Central and Eastern Europe, the Middle East, and China. Sporadic cases have been reported in the United States, especially in persons who migrated from the aforementioned areas. The majority of cases affect the nose, but extension to the soft and hard palate, upper lip, and maxillary sinuses also is frequent. This study comprises 11 patients (6 females and 5 males) with respiratory scleroma identified over a 6-year period in Guatemala. Their ages ranged from 16 to 60 years. Light microscopy showed a dense plasmacytic infiltrate, Mikulicz histiocytes, and Russell bodies within the plasma cells. Ultrastructural study revealed Mikulicz histiocytes, cytoplasmic vacuoles containing bacilli, and so-called A and B granules. We favor the term respiratory scleroma for this lesion because it affects not only the nose but also the upper and lower respiratory tracts as well as the mouth.

[Activation of the immune system in periapical infection. 1. Lympho-monocytoid and plasma cellular elements of reactive soft tissue cells]. / Attivazione del sistema immunocompetente nella patologia del periapice infetto. Nota 1: elementi cellulari della serie linfomonocitoide, plasmacellulare e propri dei tessuti molli reattivi.

The authors have carried out a study on the immunitary mechanisms which stimulate and avoid eventual alterations of infected periapex. Above all the aim of this first study has been the microscopic and ultrastructural valuation of the cellular components that characterize the process of chronic phlogosis of periradicular tissue, lymphocytes T and B, plasmacells and macrophages, and of those even more typical of the soft reactive tissues, fibroblasts and epithelial cells. It's just the interaction among these immunocompetent cells which determines the structural change of the periapical bone whose most common image of radiotransparence make it possible to diagnose the sufference of the pulpo-periapical system.

[An increase of plasma cells in the regenerated mucous membrane of maxillary sinus. Experimental study]. / Aumento de células plasmáticas en la mucosa regenerada del seno maxilar. Estudio experimental.

In ten albino New Zealand rabbits we studied in the regenerated mucosa of the maxillary sinus what happens after three months of radical removal of sinus mucosa. The study was realized by light and electronic microscopy, with special attention to the plasma cells around the submucosal glands. There is an increased of plasma cells, in a proportion of 10:1.

Immunological and ultrastructural characterization of plasma cells of human periapical chronic inflammatory lesions (granulomas).

Despite many studies on the topic, plasma cells found in human periapical chronic inflammatory lesions (granulomas) continue to present unresolved issues. In this study, we tried to assess quantitatively and qualitatively the nature of plasma cells of 4 human periapical granulomas. Samples were analyzed for relative amounts of IgG-, IgM-, IgA-, and IgE-positive plasma cells by immunohistochemistry, and for morphological changes by transmission electron microscopy (TEM). By immunohistochemistry, many plasma cells stained positively with anti-IgG and anti-IgM antibodies; fewer cells reacted with anti-IgE and anti-IgA. Russell Bodies, controversial aspects of plasma cell maturation, showed positive reactivity of the superficial layer only to antibodies against IgG and IgM. By TEM analysis, phenotypes of normal and dysfunctional plasma cells (Mott cells) were evident. Russell Bodies appeared as intra- or extracellular round vesicles, with an homogeneous internal core, and an external membrane, resembling rough endoplasmatic reticulum (RER). We can conclude that mucosal immune response is not the predominant type in the periapical lesions examined. Positive immunoreaction for IgG and IgM of Russell Bodies may be due to the residual RER membrane, whereas components of yet unidentified nature may occupy the internal core.

[Ultrastructural morphological observation on the plasma cells in periodontitis-affected human gingival tissue].

The transmission electron microscope was used to demonstrate the mechanism of immunoreaction in periodontitis-affected gingival tissue. The result showed that the number of plasma cells (PC) was the highest in infiltrated inflammatory cells and with degeneration. According to the variation of ultrastructural features of nuclei; plasma membrane (PM) and cisternae (Ci) of rough endoplasmic reticulum (RER), PC were classified into 4 stages. The chromatin of their nuclei varied from normal, to marginal concentrated, pyknosis, and karyorrhexis. The PM appeared intact, partial loss, to complete loss. The Cisternae showed varying degree of dilatation and the RER was broken into numerous discrete vesicles. The electron density of cisternae varied from low to high, and again low. The number of Russell's bodies varied from rare to increase, and then rare again. At last degenerated PC underwent apoptosis. The results show that the adult periodontitis is related to humoral immunity.

[Clinical and ultrastructural observations of juvenile periodontitis].

In this study, clinical data of 7 cases of juvenile periodontitis were analyzed in company with electron microscopic observations. It consisted of 6 females, and 1 male, aged from 12 to 18 years old. TEM showed chronic inflammation of the pocket walls, marked plasma cell and lymphocyte infiltration. Plasma cells revealed abundant dilated rough endoplasmic reticulum and were classified into three types. Numerous bacteria were found in lamina propria in one case, without any signs of phagocytosis. The collagen fibers were fragmented, dissolved and arranged out of order. The characteristics of clinical history, and the ultrastructural changes of the periodontal pocket were analyzed and discussed.

[Aspects of distribution of plasma cells at the advancing front of the lesion in chronic periodontitis: a quantitative ultrastructural study]. / Etude ultrastructurale de la distribution des plasmocytes au sein de la partie la plus apicale de lesions parodontales chroniques.

The aim of this study was to compare the distribution of plasma cells within the soft tissue walls of interdental deep pockets from patients with adult (AP) and juvenile/post-juvenile (JP/PJP) periodontitis. Biopsies from 20 patients and 3 control volunteers were examined: 5 with treated AP, 5 with untreated AP, 5 with treated JP/PJP and 5 with untreated JP/PJP. No plasma cells were seen within the epithelium from any of the biopsies examined, and they were very sparse within the connective tissue from the control specimens. In all the pathological specimens examined there was marked tissue destruction. The percentage density of plasma cells tended to be statistically significantly higher in JP/PJP than in AP, and in untreated than in treated lesions. The statistical analysis showed also that plasma cells were more abundant in a layer deep to the neutrophils lining the basement membrane. Plasma cells were also more abundant in areas of extensive histological inflammation. The plasma cells were often degenerate and such degeneration appeared more evident in JP/PJP and in areas of connective tissue devoid of vascular tissue. These findings appear to indicate an association between increase of collagen destruction and increase in plasma cell percentage density. This may relate in turn to an increase in penetration and/or virulence of components of the subgingival plaque following an increase in tissue permeability. The scarcity of Russell bodies within the plasma cells would suggest that immunoglobulin production and secretion are normal.

The hyaline cell: a distinctive feature of "mixed" salivary tumours.

We have identified and described a distinctive type of cell which is characteristic of the "mixed" salivary tumour. This "hyaline cell" or plasmacytoid cell is particularly common and conspicuous in "mixed" tumours of the palate and other sites in the mouth. It occurs also in tumours of the major glands, but with much lesser frequency. The hyaline cell is found in "mixed" salivary-type tumours in other sites, e.g. the skin. It is not present in the other types of salivary tumour, notably adenoid cystic carcinoma, adenolymphoma, mucoepidermoid and acinic tumour. Ultrastructural study suggests that the hyaline cell is an indicator of myoepithelial differentiation. Current concepts of the acceptable pathways of myoepithelial differentiation in "mixed" tumours are discussed briefly. The specificity of the hyaline cell will probably prove valuable in separating "mixed" tumours from monomorphic adenomas, thus retaining the identity of the latter. The hyaline cell is almost as distinctive a feature of "mixed" tumours as is myxochondroid tissue and its specificity is of practical value in the diagnosis and classification of salivary tumours.

New findings of a lamina densa in relation to plasma cells.

In an ultrastructural study of oral lesions in lichen planus, it was found that some plasma cells have an associated lamina densa. Subsequently, similar appearances have been found in pemphigus vulgaris, in the inflammatory cell infiltrates in dental granulomas and cysts and in a patient with Ehlers-Danlos syndrome. The lamina densa was mainly present adjacent to those parts of the membrane of the plasma cell that were invested with fibrillar connective tissue. The lamina was similar in thickness and electron density to that surrounding Schwann cells and endothelial cells. It is believed that lamina densa has not previously been reported in relation to plasma cells. It is of interest that in all other situations in which lamina densa has been described, the cells are considered to be part of the normal cell population of the tissue, whereas plasma cells are not regarded as part of the resident population of connective tissue.

Localised myeloma with osteogenesis and Russell body formation.

A case of an osteosclerotic myeloma of the mandible is described. Bone formation took the form of prominent sunray spiculation and radiologically mimicked an osteosarcoma. No other well-documented solitary lesion of this type could be found in the English literature. In addition, this tumour contained an abundance of intracytoplasmic Russell bodies and also produced a paraprotein. The paraprotein peak disappeared after resection.

A comparison of secondary palate development with different in vitro techniques.

Palatal processes from 14-day fetal C57BL mice were cultured under varying conditions for 48 hours and prepared for light and electron microscopy. Disruption of the epithelium along the medial border occurred when single palatal processes were explanted onto Millipore filters, plasma clots, or lens paper in subjacent contact with nutrient medium. Paired processes under the same culture conditions demonstrated typical midline epithelial disruption and mesenchymal fusion. Regions of mesenchymal necrosis occurred in processes grown on nutrient agar in a dish or submerged in nutrient medium. In similar cultures medial epithelial disruption did not occur in single processes and mesenchymal fusion of paired processes was either delayed or did not occur. Disruption of the epithelium along the medial border in single palatal processes, and mesenchymal fusion in paired palatal processes, occurred when palates were grown on nutrient agar supported above but in contact with nutrient medium. The results indicated that responses of palatal epithelium and mesenchyme may be altered by different in vitro procedures. These observations emphasize that many factors must be considered in interpreting developmental changes in palatal processes grown in vitro.

Penetration, clearance and retention of antigen en route from the gingival sulcus to the draining lymph node of rats.

We investigated the penetration and clearance of antigen in the rat gingiva and the antigen-specific antibody response in the draining lymph nodes. Rats were primarily immunized into the alveolar submucosa with horseradish peroxidase (HRP) in complete Freund's adjuvant. Ultrastructural demonstration of antigen and specific antibody was performed by incubation of cryosections in an HRP solution, followed by peroxidase cytochemistry. Anti-HRP antibody-containing cells were observed in the draining lymph nodes from 2 to 9 weeks after immunization. The bulk of these cells were located in the medullary cords. The extracellular antibody and antibody-containing cells were also found in germinal centers (GCs) from 3 to 9 wk, and 3 wk, respectively, after immunization. The results suggest that the specific antibody response was most enhanced 3 wk after primary immunization. Therefore, at this time we further challenged rats with the topical application of HRP to the gingival sulcus. The results showed that antigen penetrated through the junctional epithelium into the underlying connective tissue and from here was cleared by macrophages or via the lymphatics. In the draining lymph nodes, antigen first appeared in the subcapsular sinus and eventually became retained within GCs. Between 3 and 5 days, the GCs of challenged rats contained more mature-type anti-HRP antibody-containing cells than those of non-challenged rats. The sequence of events observed suggests that antigen challenge applied topically to the gingival sulcus can induce the active GC reaction in the draining lymph nodes of immunized rats.

Multiple myeloma: a study of 10 cases.

The clinical, radiographical, biochemical, microscopical and ultrastructural features of 10 cases of multiple myeloma were studied. The skull and jaw regions were frequently involved by the disease and although the diagnosis remains multidisciplinary, microscopical parameters differentiating a myelomatous bone marrow infiltrate from a reactive plasmacytosis are discussed. Biochemical and microscopical factors influencing the prognosis are highlighted and significant ultrastructural findings include erythrophagocytosis, cytoplasmic nuclear asynchrony of plasmablasts and intranuclear viral like inclusions.

Ultrastructural localization of acid phosphatase activity in plasma cells containing Russell's bodies in periodontitis.

Acid phosphatase activity was examined ultracytochemically in gingival specimens to elucidate the response of plasma cells to Russell's bodies. The acid phosphatase activity was discernible in lysosomes of various morphology, some of which contained Russell's bodies. The acid phosphatase activity was stronger in the peripheries of such lysosomes, but weak activity was also found inside Russell's bodies. These findings indicated that at least some of Russell's bodies formed within the plasma cells were degraded in autophagolysosomes.

Changes in the fine structure of the human dental pulp subsequent to carious exposure.

Sections of human pulp tissue taken from the region of a carious exposure in four young patients each having a clinical history of spontaneous dental pain were examined with the electron microscope. All the tissues examined exhibited a generalized edema, and an infiltration with lymphocytes, plasma cells, polymorphonuclear leukocytes and macrophages. Varying degree of lysis of pulp and inflammatory cells were evident. The unmyelinated nerve axons of the pulp appeared to be least affected. Extracellular lysosomes were present in many of the necrotic areas. Edematous vacuoles were noted in two of the pulp specimens. In some of the sections these vacuoles appeared to be responsible for a physical distortion of adjacent unmyelinated nerve axons. It was postulated that such distortion may be a contributing factor to the pain of pulpitis. In another of the pulp specimens, micro-organisms were found intracellularly and extracellularly. Intracellularly they were present within the cytoplasm of polymorphonuclear leukocytes and macrophages and exhibited evidence of lysis. Only two morphological forms, a gram positive rod, and a gram positive coccus were identified.