Cementogenesis and soft tissue attachment after citric acid treatment in a human. An electron microscopic study.

The four maxillary incisors and two maxillary premolars of a 25-year-old male patient were used to study epithelial and connective tissue attachment 67 days and 164 days after flap surgery and cutting of an horizontal intradentinal groove near the buccal cervical region. Three teeth were topically conditioned for 3 minutes with citric acid pH = 1. The three other teeth were used as controls. The histologic examination was carried out in double-blind conditions; the examiners did not know which specimens were acid treated until the end of the study. Two of the three cases treated with citric acid showed improved healing conditions, when compared to the controls; a more coronal position of the epithelial attachment in the dentin nick as well as a relatively important gain in connective tissue attachment. Two types of connective tissue attachment were observed. The first consisted of an attachment to dentin, without cementum formation and was characterized by a mineralization of decalcified dentin collagen spliced with collagen, newly secreted by fibroblasts. The second type involved cementum formation. Topical citric acid treatment, however, can not be considered as a completely reliable clinical procedure since in one experimental case the type of attachment observed was not better than that seen in the control.

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.

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.

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.

[Cowden disease: report of 8 cases in 2 families (author's transl)]. / Maladie de Cowden: a propos de 8 cas familiaux.

These 8 cases of multiple hamartoma syndrome are the first reported in Switzerland. Two men aged respectively of 65 and 28 years presented a cobblestone appearance of the gingiva and of the tongue ("pebbly tongue"), which suggested Cowden disease. This diagnosis was confirmed by the discovery of numberous skin lesions, a thyroid goiter, gastrointestinal polyposis, and a mild skelettal dysmorphosis. The older patient had a grade one carcinoma of the bladder; his son and his daughter presented the syndrome, which was also discovered in the family of the second patient (his father, his brother, his sister and one of her daughters). The ultrastructural study of two skin biopsies demonstrated anomalies of the fibroblasts and collagen fibers.

[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.

[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.

[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.

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.

[The intraepithelial carcinoma of the mouth mucosa and its anatomo-clinical variants]. / Le carcinome intraépithélial de la muqueuse buccale et ses variantes anatomo-cliniques.

Contrary to common opinion the intraepithelial cancer of the buccal mucosa presents clinical symptoms, but they are discreet and different from those observed in an invasive carcinoma. Usually, there is leucoplakia with an erythema and an irregular keratosis or a punctuated one. There is an erythematous variation (Queyrat's erythroplasia) which is without keratinasation. Only histological evidence can confirm the diagnosis cancer. It should be differentiated against Bowen's disease and the light, intermediated and severe dysplasias.

[The evolution of implantology --trends toward a new concept]. / Evolution de l'implantologie - tendances vers und nouvelle conception

The development if implantology during the recent years, relative to the tissue tolerance of various implant materials seems to have improved the chances of success. The disastrous results of prior years have been due to improper techniques leading to unstable biostability between tissue and implant material surface. This insufficiency of biocompatibility is not only biochemical, but also biomechanical as a consequence of very differing physical properties of osseous tissue and implant material. By increasing the surface of the implant material, making it porous, a penetration of fibres and a neoformation of bone could be observed. Thus a conjunctive attachment forms thus securing a closure of tissue around the emerging abutments. At this level, the implant must be considered under the periodontal angle. Marginal irritation must at any price be avoided, thus reducing the chance of epithelial growth into depth. Materials responding to the demands of biocompatibility are certain forms of porcelain, vitrified carbon, titanium, calcium aluminate.

[Early detection of pemphigus vulgaris: role of the dentist]. / Dépistage précoce du pemphigus vulgaire: rôle du médecin-dentiste.

Means to detect pemphigus vulgaris at an early stage are described. Its grave evolution in absence of treatment makes an early diagnosis imperative. The first signs are frequently localized in the oral mucosa and sometimes the disease remains confined to this mucosa only. Efficient and early therapy may favourably influence the course of disease, and the dentist is in a prime position to detect the characteristic lesions.

[Oral manifestations of Letterer-Siwe disease. Clinical and histological study of lesions centered in the mouth of a infant with acute and disseminated histiocytosis X]. / Manifestations buccales de la maladie de Letterer-Siwe. Etude clinique et histologique des lésions siégeant dans la bouche chez un nourisson atteint d'Histiocytose aiguë et disséminée.

The clinical, radiological and histological aspects of acute histiocytosis X of Letterer-Siwe disease are reviewed after personal observation of such cases. In spite of many advanced hypotheses the etiopathogenesis of Histiocytosis X is wide open to research. The diagnosis became possible by the discovery of histiocyte cells of a special order, the X-bodies, under the E. M. Recent research allows a classification of Letterer-Siwe disease, Hand-Schüller-Christian disease, and the eosinophilic granuloma under the same nosologic grouping. Finally, the prognosis of the Letterer-Siwe disease-so far much in the dark-may be improved by a properly conducted therapy.

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.