Immunohistochemical detection of S-100 protein in human deciduous dental pulp.

S-100 protein was investigated in the temporary dental pulp by the immunoperoxidase technique, using the avidin-biotin complex method. The results showed that there was a strong positive reaction in the Schwann cells ensheathing axons and nerve fibers. The other cells within the pulp were immuno-negative. S-100 protein and the results of the present study are discussed.

Distribution of neural and neural-crest-related antigens in human dental pulp by immunohistochemistry.

Human teeth (formalin-fixed, demineralized and paraffin-embedded as well as frozen sections of human dental pulp) were examined by immunohistochemistry to detect the presence and distribution of a series of neural and neural-crest-associated antigens: S-100 protein, neuron-specific enolase (NSE), glial fibrillary acid protein (GFAP), myelin basic protein (MBP) and neurofilaments (NF). Although several experimental pieces of evidence support a neural crest derivation for dental papilla and odontoblasts with the histological method used in the present study, these structures were immunonegative for most of the markers employed in the present investigation. Indeed, mesenchymal cells as fibroblasts and endothelial cells were devoid of immunostaining. Schwann cells were strongly immunostained by S-100, NSE and GFAP. Nerve fibres running in the pulp showed a positive labelling for NF, S-100 and MBP antisera. It is concluded that the lack of labelling of pulp cells (excepting nerves) by the neural and neural-crest-associated antibodies could be due to a loss of capacity to express these antigens during differentiation. However, the possibility that these antigenic determinants are expressed but outside the limits of sensitivity of immunohistochemistry cannot be ruled out. Further studies, including molecular biology techniques, are required to clarify these alternatives.

Expression of intermediate filaments and actins in human dental pulp and embryonic dental papilla.

The localization of different cytoskeletal proteins (keratin, vimentin, desmin, actin, and alpha-smooth muscle actin) was examined by immunohistochemistry in normal human adult dental pulp and compared with dental papilla of tooth germs. Keratin and actin were localized in enamel organ. Vimentin and actin were observed in the dental papilla and in the adult dental pulp. Desmin and alpha-smooth muscle actin were present only in the vessel walls. These data are discussed paying particular attention to the origin and the peculiar functional characters of the dental papilla and pulp.

Comparative immunohistochemical analysis between jaw myxoma and mesenchymal cells of tooth germ.

The histogenesis of jaw myxoma is still debated. According to some authors it arises from the primitive mesenchymal components of developing teeth. In this study, we have studied the expression of S-100 protein and vimentin in dental follicle, dental papilla and periodontal ligament cells using monoclonal and polyclonal antibodies. Myxoma of the jaw expresses vimentin and S-100 protein. On the contrary, as compared to jaw myxoma, the normal developmental structures were immunonegative for S-100 protein but stained for vimentin. These results could indicate a difference in the derivation other than tooth mesenchyma.

The connective tissue cells of human dental pulp: an histologic and immunohistochemical study.

Twenty human healthy teeth were extracted for orthodontic purposes and processed for histological, and immunohistochemical examination. Odontoblasts were pseudostratified in depth of 1-8 cells in pulpward direction showing the zone of Weil and the cell-rich zone in coronal third pulp. In the central part of pulp tissue, fibroblasts were arranged as a network. These cells strongly immunoreacted with an antibody (monoclonal and polyclonal) directed against the intermediate filament vimentin. The product reaction was specifically located in the cytoplasm. Near vessels occasional lymphocytes and mast cells were also present. Collagen fibers formed a plexus below the cell-rich zone in middle and coronal pulp.

[Myxoma of the jaws]. / Il mixoma dei mascellari.

A review of the literature and two observations made by the Authors regarding maxillary myxoma allow a closer analysis to be made of this rare benign tumour which is, however, often recurrent in young adults. Maxillary myxoma is identified by the appearance of a non-inflammatory and often painless swelling which, in radiological terms, appears to have a zone of multilocular and sometimes unilocular osteolysis. In histological terms, this globular whitish-greyish gelatine-like tumour is made up of an abundant stroma which encloses star-shaped or fusiform cells and rare collagen fibres. Treatment should be conservative where possible since radical surgery does not preclude recurrence; follow-up should be regular and long in order to ensure an early diagnosis of recividation. Although it is considered an odontogenic tumour, the odontogenic nature of maxillary myxoma has not been undisputably ascertained. The term maxillary myxoma is therefore preferable to that of odontogenic myxoma.

[Psychogenic oral paresthesia]. / Les paresthésies buccales psychogènes.

Psychogenic oral paresthesia represent a proteiform condition, more and more frequent. The failure to recognize it can lead to unjustified investigations or/and procedures. These manifestations are secondary to a psychic problem which varies in severity. In most cases, the establishment of a trust relationship, explanations to the patient and eventually a psychotherapy are sufficient to eliminate the symptoms. In severe cases, a psychotherapy or a psychiatric treatment are almost always necessary.

[Focal epithelial hyperplasia]. / Iperplasia epiteliale focale.

Five cases of "focal epithelial hyperplasia" (FEH) of the oral mucosa observed in Switzerland are reported. The patients were of Turkish and North African extraction. The lesions of FEH were multiple, painless, located at various sites of the oral mucosa including the tongue in the form of either soft papules or hard nodules. Evidence of a human papilloma virus origin was ascertained. Among the 1067 cases reported in the literature and reviewed for this study, this condition has been described to occur among American Indians, Eskimos and North African, also in Israeli and European cases the disorder was often reported in individuals of Turkish or North African extraction.

Felodipine-induced gingival hyperplasia: a clinical and histologic study.

This paper reports, for the first time, gingival hyperplasia in a patient treated with felodipine, a drug which belongs to the group of calcium ion antagonists. The observed gingival overgrowth was most significant in the area of interdental papillae of the anterior region of the mouth. The described hyperplastic tissue was characterized by a firm and pale appearance, with a normally stippled pattern. Histopathologically, a conspicuous increase of fibrous connective tissue, as well as an inflammatory infiltrate and hyperplasia of the overlying epithelium were observed. Consequently, the present observation adds another drug to the list of substances capable to induce gingival hyperplasia.

[Lichen planus. Clinical diagnosis, epidemiology and pathogenesis]. / Lichen planus. Diagnosi clinica, epidemiologia e patogenesi.

Lichen planus is a common mucocutaneous disease of unknown etiology which was initially described a century ago. The specific etiology remains unclear. A number of relationships between lichen planus and other conditions have been noted. The lesions occur most commonly on the buccal mucosa. Gingival involvement occurs in approximately 10% of reported cases. The appearance of lichen planus is extremely variable which leads to confusion with other clinically similar disease entities.

[Intramandibular inclusions of salivary gland tissue]. / Inclusioni intramandibolari di tessuto ghiandolare salivare.

Salivary gland tissue inclusions in the mandible appear as well delimited radiolucency areas, asymptomatic, usually located in the mandibular angle and sometimes in the premolar canine and symphysis regions. The examination of 8,500 radiographs has demonstrated an incidence of one radiolucent area at the mandibular angle every 500 radiographs. Our result is slightly inferior to the mean reported in the literature. Seven cases were examined. Six of them have been treated surgically and histologically. At exploration a defect in the lingual cortical plate was found. The cavities were filled by salivary gland tissue. The contents of the cavities were attached via the lingual cortical defect to the near salivary gland. The cause of such radiolucency situated in the mandibular angle seems to be an altered resorption and apposition process of the bone triggered by a modification of the salivary glands elasticity; on the contrary, the salivary inclusions in the symphysis region is referred to as embryonic origin. In the literature different terms are used often in relation with a pathogenetical hypothesis; in this paper we suggest rather a description terminology such as intramandibular salivary tissue.

Immunohistochemical staining for vimentin filaments and S-100 protein in myxoma of the jaws.

Two jaw myxomas have been analyzed by a panel of antibodies to characterize this tumour type. Vimentin, but not keratin, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), neurofilament (NF), desmin and Factor VIII-related antigen (FVIII-AG), demonstrated positivity in the cytoplasm of the neoplastic cells. Moreover, an antibody against S-100 protein also showed a strong positive reaction in the cytoplasm of the tumour cells examined. Thus directly indicating a mesenchymal derivation for odontogenic myxoma, and is the first demonstration of S-100 protein within the cells of this tumour type.

Retinoid-binding proteins in human oral mucosa.

Vitamin A affects epithelial differentiation and growth via at least 3 different binding proteins. The specific delivery of extracellular retinol to target cells is performed by plasma retinol-binding protein (RBP) while cellular retinol- and retinoic acid-binding proteins (CRBP and CRABP) are implicated in the cellular action of the 2 natural retinoids. We have studied the levels of these 3 binding proteins by gel filtration and polyacrylamide electrophoresis in human oral mucosa, epithelium and chorion and compared it to those found in keratinizing human epidermis. The levels of CRABP in oral epithelium were markedly higher (about 4 times) than that of epidermis whereas CRBP was in a similar amount in epithelium chorion, dermis and epidermis. RBP with preserved affinity for retinol, was present in the epithelium of oral mucosa whereas only degraded RBP was detected in epidermis. These results suggest (i) a higher specific retinol delivery and (ii) a distinct cellular metabolism of retinoic acid in the oral epithelium as compared with epidermis. Since cornification occurs when keratinocytes are deprived of retinol, it might be that our observations are linked to the absence of cornification in the human oral mucosa. Further, high levels of CRABP in mucosal epithelium might have therapeutical implications because the synthetic retinoids used in human therapy bind to CRABP.

Fibrinolytic alveolitis and its prevention.

This study aimed at testing the clinical efficacy of a topical prevention of FA, the sample comprising 300 cases of extractions. A sponge was inserted in the socket of each of them, dividing the sample into 3 equal groups: group A (gelatine), group B (gelatine + Solcoseryl) and group C (gelatine + Solcoseryl + propyl-hydroxy-benzoic-acid). The global incidence of FA was a comparatively high, 7.6%, which could be related to the pool of patients included in the study as to the presence of teeth and techniques more prone to complications. No specific clinical characteristic has been isolated (distribution within sex, age, teeth, etc.) which could contradict data collected from other authors. The incidence was lower in the groups B (3%) and C (7%) as compared to group A (13%), but only sponges of group B demonstrated a clinical and statistical efficacy, according to the high number of lower third molar extractions. In contrast, the addition of Solcoseryl proves efficient and does not delay healing, according to previous histological studies. This last characteristic has to be confirmed in the experimental conditions described in our study, as has its mode of action. The ultimate mechanism of FA has still, in our opinion, to be better defined well before the restatement of a topical prevention of FA.

[Focal epithelial hyperplasia: first cases in Switzerland and review of the literature]. / L'hyperplasie épithéliale focale: premiers cas suisses et revue de la littérature.

Three cases of 'focal epithelial hyperplasia' (FEH) of the oral mucosa observed for the first time in Switzerland are reported. The patients were of Turkish and North African extraction. The lesions of FEH were multiple, painless, located at various sites of the oral mucosa including the tongue, in the form of either soft papules or hard nodules. Evidence of a human papilloma virus origin was ascertained. Among the 1,067 cases reported in the literature and reviewed for this study, this condition has been described to occur among American Indians, Eskimos and Cape Coloureds; also in Israeli and European cases the disorder was often reported in individuals of Turkish or North African extraction.

[Osteoblastoma of the jaws. 2 cases and a review of the literature]. / Ostéoblastome des maxillaires. Deux observations et revue de la littérature.

The authors report on two cases of osteoblastoma: one of the maxilla in a twenty-two year old woman, the other of the mandible in a thirty-eight year old woman. In the two cases, the lesions were discovered after a systematic X-ray examination and they were treated by curettage. To date, sixty-seven cases of jawbone osteoblastoma and eleven cases of osteoid osteoma, a lesion which resembles and is perhaps similar to the osteoblastoma, have been reported in the literature. The authors develop the differential diagnosis and study the relationship between these two varieties of a same tumor or pseudo-tumor.