Anales de la Facultad de Odontologia最新文献

The structural, ultrastructural and histochemical studies of tongues of human fetuses of 8 to 32 weeks development, were carried out to evaluate the possible chronologic coincidences in the differentiation process of the histologic components during organogenesis. From week 8 to 32, the epithelium increased its cellular layers, becoming flat, stratified, with parakeratinized areas, abundant desmosomes, tonofilaments and scarse intracellular granules. Chorionic fibers increased concomitantly, decreasing mucosubstances. Rudimentary papillae appeared on the dorsal surface of the tongue at 8 weeks, the fungiform ones being evident at 12 weeks. Glycoproteins in the basament layer became evident along with the papillary differentiation, reaching their definitive form at 20 weeks. Myoblasts were observed at 20 weeks. Glandular buds were noticed at the early age studied as were rich in glycogen inclusions and transversal striations were at 20 weeks the structural and ultrastructural differentiated acini, with PAS positive, metachromatic and alcianophilic secretions. The cytochemical changes observed are indicative of the cell differentiation process and tissues participating in the histogenesis present a similar rhythm of differentiation and growth.

A comparative analysis of the in vitro quelating effect of Endodent, Largal Ultra and Salvident was done evaluating the decrease of dentine weight that they produced. The samples of dentine, each time included in the same volume of the three agents during 24 and 48 hours. Largal Ultra was in the 100% of the cases, the quelating that more decrease of weight produced.

The purpose of this study was to assess the reliability of toluidine blue stain in determinating the biopsy site in 65 patients with red and white oral lesions. These patients were studied by comparing toluiding blue dye uptake clinically with a simultaneous biopsy. The microscopic analysis resulted in a false positive rate of 10.5% (previously we had established that the 6% were inflammatory lesions, always positive). We did not find false negatives. The reliability of the toluidine blue technique was 95.38%.

The Streptococcus mutans counts--added to lactobacili depicting test--are an useful instrument in cariology when determining the risk groups. In studies concerning a large number of patients the S. Mutans count in saliva test are the most accesible. Nevertheless, they are very expensive and also complicate to carry out. Simplified techniques which depict S. Mutans on the basis of adherence tests have been perfected. The most suitable from them, taking into account our working conditions, is the Matsukubo test. We deemed it interesting to correlate this test and the Gold medium count. The study has been carried out with three different populations using both techniques at the same time. As per the correlation indices obtained we conclude that the Matsukubo technique and the count have a significant correlation between them. Due to its low cost, the simplicity of its realization, as well as its easy reading it can be effectively used as a primary procedure when studying populations large in number. Through this method selection will be made of the patients to be studied applying more precise microbiological techniques.

The metastasizing pleomorphic adenoma of the salivary glands is a rare variant of pleomorphic adenoma with a benign microscopical appearance, but malignant biological behaviour and production of metastasis. The histopathological study with the routine techniques is not enough for disclosing the nature of these tumors and they are most of the times underdiagnosed as benign. The correct diagnosis, almost always too late, is evident after several recurrences and the detection of metastatic foci. The number of nucleolar organizing regions (NORs) detected with the silver colloid method can be used in histopathology to determine the degree of cell activity. We report the findings in a case of metastasizing pleomorphic adenoma of the submandibular gland. This technique demonstrated to be useful for the diagnosis and characterization of the metabolism of these tumors.

A children's population, aged from 2 to 5 years, was studied for three years. Bacteriological and clinical criteria were followed, with a determination of the M. st level in non-stimulated saliva in the age-groups of 3, 4 and 5 years. We found, as Alaluusua did, a correlation between the M. st level in saliva and the number of caries. With this study, a large number of caries-free children had a low M. st level. The largest amount of caries appears in children with a high M. st level. The highest caries incidence in this population appears at the 4 year children group. It has to be remembered that this is an age-group with specific characteristics. Caries is a disease depending on many factors and the M. st level would be very significant to an early detection of risks, but should be evaluated considering all the parameters as a whole. Its predictive value is not sufficient by itself but it has an unquestionable value when detecting risk patients of an early age. Therefore, treatment has to be the result of an etiological diagnosis addressed to prevention after an evaluation of all the factors related with the caries disease.

This techniques using Rogosa agar modificated with green of bromocresol, placed into tubes (10 ml) containing 4 ml, was developed for qualitative estimation in saliva of lactobacilli in a quick form. We spotted with a pipette 0.1 ml of saliva dilution into different tubes with the culture medium previously mentioned. The tubes were incubated at 37 degrees C for 24 and 48 hours. The results obtained showed a great agreement with the number of latobacilli in the agar.

The number of roots and cannals were observed and studied in upper bicuspids. For the study of the root cannals was used a diafanization technique. The results were prosessed by stadistic analysis and compared with those published. By the observation, in this work, was stated that the first upper bicuspid has one root and two cannals in the most of the cases. This situation was confirmed by stadistic analysis. Conclusions were extracted refering them to the clinical application.

We processed 28 samples of human gingiva in health or paradential illness, of 15 patients between 20 to 67 years old. In 306 histologies cuts we made different staining to light microscope. We analyzed presence, distribution, diameter and relations of the elastic, elaunin and oxytalan fibers. The patron of distribution fibrilar of the elastic system gingival was different than other zones of the body. The description had made in three zones of the gingival connective tissue: deep, subpapilar and papilar zones. The elastic fibers had less numerous and larger diameter than the elaunin y oxytalan ones. Their repair was irregular. The elaunin followed the colagen fibers. The oxytalan formed delicates nets in the lodge of connective tissue, inflamatories infiltrates and interfibrilar spaces. They came to the basal membrane perpendicularly or oblicualy, isolated or in little bundles. The fibers of elastic system increased principaly in inflamed gingiva of teeth with overburden, though they supported the low proportion that exist at health gingiva. They appeared at the little vases wall and were increased at zones next to edentate spaces. The analogy and close entail between the elaunin and oxytalan fibers to colagen ones, made think in a relation of reenforcement of colagen, increased at paradential illness.

The existence, frequency and origin of the middle superior alveolar nerves was studied in 100 cases. 40 dried bones and 40 formaldehyded bones with the nerves in situ, were observed by transilumunation; and 20 hemi sectioned heads were disected with the help of transilumination. The middle superior alveolar nerve was found in 57 cases, in 35 arose from the Maxillary nerve trunk in the infraorbital canal and in 22 arose from the Maxillary nerve trunk in the tuberosity face of the maxillary bone, very near of the beginning of the infraorbital canal. A enlarged review of the literature and the comparison with our findings, was made too.