Angioarchitectural arrangements in corrosion cast of the nasal septum of the Mongolian gerbil.

The three-dimensional architecture of the vascular network of the nasal septum of the gerbil rat was studied using the corrosive resin cast technique. The angioarchitecture of the nasal septum observed with scanning electron microscopy (SEM) showed that a vascular network is disposed in the lamina propria. The capillaries, arterioles, venules and arteries were closely observed in different areas of the nasal septum mucosa.

Scanning electron microscopy of the rat tongue mucosa with special attention to the bacteria on epithelial cell membranes.

The authors examined the filiform and fungiform papillae surfaces of rat tongue by scanning electron microscopy showing the numerous groupings of bacteria on the epithelial cell membranes. The fungiform papillae were round in shape and present few bacteria. The epithelial cell of filiform papillae revealed numerous streptococci. The grouping of the bacteria are attached on the epithelial cell membrane, demonstrating three-dimensional SEM images.

Celecoxib treatment does not alter recruitment and activation of osteoclasts in the initial phase of experimental tooth movement.

In a previous study, we reported that the short-term treatment with celecoxib, a non-steroidal anti-inflammatory drug (NSAID) attenuates the activation of brain structures related to nociception and does not interfere with orthodontic incisor separation in rats. The conclusion was that celecoxib could possibly be prescribed for pain in orthodontic patients. However, we did not analyze the effects of this drug in periodontium. The aim of this follow-up study was to analyze effects of celecoxib treatment on recruitment and activation of osteoclasts and alveolar bone resorption after inserting an activated orthodontic appliance between the incisors in our rat model. Twenty rats (400-420 g) were pretreated through oral gavage with celecoxib (50 mg/kg) or vehicle (carboxymethylcellulose 0.4%). After 30 min, they received an activated (30 g) orthodontic appliance, set not to cause any palate disjunction. In sham animals, the appliance was immediately removed after introduction. All animals received ground food and, every 12 h, celecoxib or vehicle. After 48 h, they were anesthetized and transcardiacally perfused through the aorta with 4% formaldehyde. Subsequently, maxillae were removed, post-fixed and processed for histomorphometry or immunohistochemical analyses. As expected, incisor distalization induced an inflammatory response with certain histological changes, including an increase in the number of active osteoclasts at the compression side in group treated with vehicle (appliance: 32.2 ± 2.49 vs sham: 4.8 ± 1.79, P<0.05) and celecoxib (appliance: 31.0 ± 1.45 vs sham: 4.6 ± 1.82, P<0.05). The treatment with celecoxib did not modify substantially the histological alterations and the number of active osteoclasts after activation of orthodontic appliance. Moreover, we did not see any difference between the groups with respect to percentage of bone resorption area. Taken together with our previous results we conclude that short-term treatment with celecoxib can indeed be a therapeutic alternative for pain relieve during orthodontic procedures.

Sustained release carriers used to delivery bone morphogenetic proteins in the bone healing process.

Bone morphogenetic proteins (BMPs) are multi-functional growth factors belonging to the transforming growth factor beta superfamily, especially BMP-2, induce bone formation in vivo, and clinical application in repair of bone fractures and defects is expected. However, appropriate systems to delivery BMPs for practical use need to be developed with the objective to heal cartilage and bone-related diseases in medical, dental and veterinary practice. Thus, the aim of this article was to present an overview of the principals carriers used to delivery BMPs and alternative delivery systems for these proteins.

Histological and histomorphometrical alterations of the periodontal ligament in gerbils submitted to teeth extraction.

This study verified the effect of unilateral teeth extraction on the periodontal ligament in gerbils (Meriones unguiculatus). Ten adult male gerbils weighing about 50 g had induced occlusal alterations by upper left molar extractions while the other ten animals, only submitted to surgical stress, were considered as controls. The periodontal ligament was characterized by qualitative and quantitative analysis, histological description and histomorphometric quantification. Significant alterations were observed on the left side of the experimental group (P < 0.05), the hypofunctional region, when it was compared with the contralateral side and the corresponding region of the control group. Two months after occlusal alterations induced by unilateral teeth extraction, atrophic histological alterations and a decrease in the periodontal space on the ipsilateral side characterized the periodontal ligament. In this study it was possible to conclude that the gerbil can be used in experimental models attempting to correlate the periodontium's biological response to various mechanical stresses, as the periodontal ligament was shown to be highly sensitive to occlusal alterations.

Morphologic analysis of the "spina mentalis" in adult mandibles of Brazilian whites and negroes.

This study was carried out to verify the morphology of the spina mentalis. We observed 275 human adult mandibles of both sexes and ethnic groups. An analysis of the results allows the following conclusions: 1. The spina mentalis exists in 90.04% +/- 1.8 of the mandibles of Whites and Negroes; 2. The typical form with four tubercles, as described by some authors, is rarely found; 3. In most cases it characterized by the presence of two upper tubercles (27.27% +/- 7.2); two superior tubercles and one inferior (24.72% +/- 6.7), and one elongated median tubercle (24.0% +/- 6.6); 4. The forms and volumes of the tubercles are very irregular and seem not to depend on age, sex or ethnic group; 5. The spina was absent in 9.8% +/- 3.2 of the cases, especially in mandibles of White teethless individuals; 6. An hypertrophic spina mentalis, generally formed at the expenses of the upper tubercle, is observed in only 1.45% +/- 0.5 of the cases.

About the existence and endings of nerve fibres in the Cebus apella monkey's upper lip.

In the present research, fibres and nerve endings of upper lip of the Cebus apella monkey have been studied. Upper lip of 8 Cebus apella were analysed. The pieces were prepared according to the technic of Castro's silver impregnation and submitted to serial sections 8 micra thick. Our results permit to conclude that the Cebus apella monkey's upper lip has a great number of free nerve endings, between connective and epithelial layers in the mucosa and in the skin. The aspects of nerve fibres and their free and organized endings, like Meissner's corpuscles, in the upper lip mucosa of the monkey, allow comparison of similarity with those of man. The nerve endings in the lip skin of the Cebus monkey are also abundant, characterizing the hair follicles and sebaceous glands innervation and the free nerve endings encountered in the connective tissue as well as in the sub-epithelial layer.

Morphological observations of the sensory nerve endings of the Calomys callosus' lingual mucosa, employing the silver impregnation method

Estudaram-se as características morfológicas das terminaçöes nervosas sensitivas da mucosa lingual de Calomys callosus, empregando-se a técnica de impregnaçäo pela prata. Para a obtençäo das peças, cada animal foi anestesiado com injeçäo intraperitonial de tionembutal sódico. As peças foram fixadas em soluçäo de formalina a 10 por cento por um período de 20 dias à temperatura ambiente e cortes espessos de 40-60 micrometros foram obtidos em criostato Linde. As preparaçöes foram coradas pela técnica de impregnaçäo pela prata. De acordo com os nossos resultados podemos concluir que: 1) todas as regiöes (anterior, média e posterior) da mucosa dorsal da língua de Calomys callosus possuem terminaçöes nervosas sensitivas; 2) as terminaçöes nervosas podem ser simples ou complexas localizando-se no tecido conjuntivo da lâmina própria ou no interior das papilas conjuntivas das papilas filiformes, fungiformes e valadas, 3) as terminaçöes nervosas livres no interior das papilas fungiformes dispöem-se longitudinalmente ou formando uma rede complexa de fibras nervosas terminais