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Facial paralysis can result in severe implications for the patients. However, stem cell biology has become an important field in regenerative medicine since the discovery and characterization of mesenchymal stem cells. Our aim was to evaluate the regeneration after facial nerve crush injury and application of human immature dental pulp stem cells (iDPSC). For this study 70 Wistar rats underwent a unilateral facial nerve crush injury and were divided into two groups: Group I (GI): Crushed; Group II (GII): Crushed and iDPSC, and distributed into study periods of 3, 7, 14, 21, and 42 postoperative days. Facial nerve regeneration was analyzed via functional recovery of whisker movement, histomorphometric analysis, and immunoblotting assay. The results show that GII had complete functional recovery at 14 days, while GI recovered after 42 days. Also, regarding the facial nerve trunk, GII presented histological improvement, evidencing better axonal and structural organization of the myelin sheath, and exhibited statistically higher values for the outer and inner perimeters and g-ratio. Nevertheless, GI exhibited statistically higher values for the thickness of myelin sheath. In the buccal branch, no differences were observed for all parameters between groups. At 42 days, both groups GI and GII were close to the levels observed for the control group. Concerning nerve growth factor expression, GII exhibited statistically greater values ( p < 0.05) compared with the control group at 7 days. In summary, a single injection of human iDPSC promoted a positive effect on regeneration of the facial nerve trunk after 14 days and provided an alternative to support regeneration following peripheral nerve injury.

This study was designed to evaluate the anti-inflammatory effects of a curcumin treatment on the knee of rats with induced osteoarthritis. Fifteen adult rats were used and divided in three groups: the osteoarthritis group (OAG), control group (CG–without induction of osteoarthritis), and curcumin-treated osteoarthritis group (COAG). Osteoarthritis was induced in the right knee of rats in the OAG and COAG by administering an intra-articular injection of 1 mg of zymosan. Fourteen days after induction, 50 mg/kg curcumin was administered by gavage daily for 60 days to the COAG. After the treatment period, rats from all groups were euthanized. Medial femoral condyles were collected for light microscopy and immunohistochemical staining. The expression of SOX-5, IHH, MMP-8, MMP-13, and collagen 2 (Col2) was analyzed. The COAG exhibited an increase in the number of chondrocytes in the surface and middle layers compared with that of the OAG and CG, respectively. The COAG also showed a decrease in the thicknesses of the middle and deep layers compared with those of the OAG, and an increase in Col2 expression was observed in all articular layers (surface, middle, and deep) in the COAG compared with that in the OAG. SOX-5 expression was increased in the surface and deep layers of the COAG compared with those in the OAG and CG. Based on the results of this study, the curcumin treatment appeared to exert a protective effect on cartilage, as it did not result in an increase in cartilage thickness or in MMP-8 and MMP-13 expression but led to increased IHH, Col2, and SOX-5 expression and the number of chondrocytes.

Midpalatine suture disjunction is a routine procedure in the orthodontic clinic; however, the cellular events involved in the procedure have not yet been completely explained. The aim of this study was to verify the tissue events, particularly those related to osteogenic differentiation, which occur in the region of the palatal suture after disjunction, by means of histologic and immunohistochemical analyses of the following noncollagenous proteins: BSP, OCC, OPN and ONC. In this study, 10 male Wistar rats aged two months and weighing approximately 250 g were used. The animals were divided into two groups of five animals: Group I – control (mini-implant placement) and group II – experimental (placement of mini-implant and disjunction spring made of 0.60mm steel wire, with an initial load of 2N (200 grams)). After 21 days, the animals were sacrificed and histological and immunohistochemical analyses were performed for the noncollagenous proteins. The use of the spring anchored to mini-implants promoted the disjunction of the median palatal suture, with a V-shaped opening, in which the base faced the superior region (at the nasal cavity) and the vertex was in the inferior region of the oral cavity (at the palatal bone). It could be concluded that after disjunction, there was presence of osteoblasts in an osteoid matrix in the region of the median palatal suture, and the immunohistochemical expression of the noncollagenous proteins increased in all the analyzed parameters, expression being most significant for ONC.

Assess morphologically the efficacy of constant dose (CD) or gradual dose (GD) in photobiomodulation therapy (PBMT) during the regeneration process of rats' mental nerve after compression lesion.Forty-eight male Wistar rats were used and divided into four groups (n = 12): negative control (NC): lesion by compression; positive control (PC): no lesion; GD: lesion by compression and PBMT with GD; and CD: lesion by compression and PBMT with CD. One day after the surgery, the groups GD and CD underwent PBMT daily in three equidistant points around the incision area. The parameters were wavelength of 808 nm, 100 mW, CD received treatment with 120 J/cmIt was observed that PBMT was able to accelerate the process of nerve regeneration presenting an increase in the number of myelinated fibers starting at 14 days of treatment for groups CD and GD, and at 21 days they were similar to PC. It was observed a better lamellar organization of myelin sheath at 7 days for GD and at 14 days for CD, similar to PC. Both GD and CD presented significant differences compared to NC and PC for thickness of the myelin sheath, outer perimeter, internal area, and number of myelin fibers.PBMT presented positive effect on the regeneration of nerve starting at 14 days, and after 21 days there was no difference between GD and CD.

Mesenchymal stem/stromal cells (MSCs) play crucial roles in maintaining tissue homeostasis during physiological turnovers and injuries. Very little is known about the phenotype, distribution and molecular nature of MSCs in freshly isolated human salivary glands (SGs) as most reports have focused on the analysis of cultured MSCs. Our results demonstrate that the cell adhesion molecule CD34 was widely expressed by the MSCs of human major SGs, namely parotid (PAG), sublingual (SLG) and submandibular (SMG) glands. Further, gene expression analysis of CD34+ cells derived from fetal SMGs showed significant upregulation of genes involved in cellular adhesion, proliferation, branching, extracellular matrix remodeling and organ development. Moreover, CD34+ SMG cells exhibited elevated expression of genes encoding extracellular matrix, basement membrane proteins, and members of ERK, FGF and PDGF signaling pathways, which play key roles in glandular development, branching and homeostasis. In vitro CD34+ cell derived SG-MSCs revealed multilineage differentiation potential. Intraglandular transplantation of cultured MSCs in immunodeficient mice led to their engraftment in the injected and uninjected contralateral and ipsilateral glands. Engrafted cells could be localized to the stroma surrounding acini and ducts. In summary, our data show that CD34+ derived SG-MSCs could be a promising cell source for adoptive cell-based SG therapies, and bioengineering of artificial SGs.

Stem cells are capable of generating various cell lines and can be obtained from adult or embryonic tissues for clinical therapies. Stem cells from deciduous dental pulp are among those that are easily obtainable from adult tissues and have been widely studied because of their ability to differentiate into a variety of cell lines in the presence of various chemical mediators. We have analyze the expression of several proteins related to the differentiation and proliferative potential of cell populations that compose the tooth germ of human fetuses. We evaluate 20 human fetuses of both genders. After being paraffin-embedded, cap and bell stages of tooth germ development were subjected to immunohistochemistry for the following markers: Oct-4, Nanog, Stat-3 and Sox-2. The studied antibodies showed nuclear or cytoplasmic immunnostaining within various anatomical structures and with various degrees of expression, indicating the action of these proteins during tooth development. We conclude that the interrelationship between these transcription factors is complex and associated with self-renewal and cell differentiation. Our results suggest that the expression of Oct-4, Nanog, Sox-2 and Stat-3 are related to differentiation in ameloblasts and odontoblasts.

Adult stem cells research has been considered the most advanced sort of medical-scientific research, particularly stem cells from human exfoliated deciduous teeth (SHED), which represent an immature stem cell population. The purpose of this review is to describe the current knowledge concerning SHED from full-text scientific publications from 2003 to 2015, available in English language and based on the keyword and/or abbreviations ‘stem cells from human exfoliated deciduous teeth (SHED)', and individually presented as to the properties of SHED, immunomodulatory properties of SHED and stem cell banking. In summary, these cell populations are easily accessible by noninvasive procedures and can be isolated, cultured and expanded in vitro, successfully differentiated in vitro and in vivo into odontoblasts, osteoblasts, chondrocytes, adipocytes and neural cells, and present low immune reactions or rejection following SHED transplantation. Furthermore, SHED are able to remain undifferentiated and stable after long-term cryopreservation. In conclusion, the high proliferative capacity, easy access, multilineage differentiation capacity, noninvasiveness and few ethical concerns make stem cells from human exfoliated deciduous teeth the most valuable source of stem cells for tissue engineering and cell-based regenerative medicine therapies.

Capybara is the largest rodent in the world and displays a seasonally dependent herbivore feeding behavior. Here, we present an anatomical contribution for understand this fact, by light, scanning, and transmission electron microscopy methodologies for tongue tissue analysis. The histological preparations revealed filiform, fungiform, vallate, and foliate papillae on the dorsal mucosa of the capybara tongue. The epithelial layer exhibited a lining of keratinized stratified squamous epithelial cells. The lamina propria was characterized by a dense connective tissue composed of the primary and secondary papillar projections. We also revealed the original aspects of the connective papillae. The shapes of the papillae varied by region of the tongue, and filiform, fungiform, vallate, and foliate papillae and subjacent layers of muscular fibers were observed. Pyriform taste buds occupying the epithelial layer of fungiform, vallate and foliate papillae were identified and the intracellular components of the taste buds and the intracorpuscular amyelinated nerve fibers were observed. The taste buds were characterized by the distribution of granular endoplasmic reticulum throughout the perinuclear area, the Golgi apparatus, and mitochondrial assemblies of various distinct diameters. Mitochondrial accumulation was also observed in the collagen bundle-surrounded amyelinated nerve fibers beside the basal cells. Therefore, these peculiar anatomical descriptions may contribute to understanding the adaptation of the feeding behavior of capybaras in a seasonally changing environment.

The aim of this study was to analyze the rat temporomandibular joint (TMJ) syno- vial membrane at different ages using light, scanning, and transmission electron microscopy. Under light microscopic analysis, the TMJ structures were observed such as condyle, capsule, disk, the synovial membrane collagen type, and cells distribution. In the scanning electron microscopy, the synovial membrane surface exhibited a smooth aspect in young animals and there was an increase with ageing in the number of folds. The transmission electron microscopic analysis showed more synoviocytes in the synovial layer in the young group and still a great number of vesicles and cis- terns dilation of rough endoplasmic reticulum in the aged group. In the three groups, a dense layer of collagen fibers in the synovial layer and cytoplasmic extensions were clearly seen. It was possible to conclude that synovial membrane structures in aged group showed alterations contributing to the decrease in joint lubrication and in the sliding between disk and joint surfaces. These character- istic will reflect in biomechanics of chewing, and may cause the TMJ disorders, currently observed in clinical processes. Microsc. Res. Tech. 75:1522-1527, 2012. V C 2012 Wiley Periodicals, Inc.

Objetivo: verificar se o tratamento ortodontico com a tecnica Bioprogressiva de Ricketts provocou alteracoes beneficas ou nao nas proporcoes aureas avaliadas. Material e metodos: Resultados: Conclusao: durante o tratamento ortodontico em questao, a maior parte das proporcoes faciais iniciais que nao apresentavam valores proximos da proporcao divina, aproximaram-se dos valores considerados como ideais, havendo uma melhora estetica da face. a avaliacao cefalometrica mostrou que as proporcoes aureas (A-1/1-Pm; Xi-6/Xi-Pm e 6-1/6-PTV) apresentaram diferenca significativa entre os valores pre e pos tratamento e as proporcoes (FH-A/A-PM e Xi-Co/Xi-Pm) nao apresentaram nenhuma alteracao significativa entre o inicio e final dos tratamentos ortodonticos realizados neste estudo. Quatro proporcoes (FH-A/A-Pm; A-1/1-Pm; Xi-6/Xi-Pm; e 6-1/6-PTV) apresentaram aproximacao do valor aureo enquanto uma (Xi-Co/Xi-Pm) se distanciou desse valor. A terceira proporcao (Xi-6/Xi-Pm) foi a que apresentou o melhor restabelecimento em comparacao com o valor aureo. foram realizadas 54 telerradiografias em norma lateral, com as quais se obteve os cefalogramas antes e pos-tratamento ortodontico completo de uma amostra composta por 27 pacientes de ambos os generos, portadores de ma oclusao Classe II, divisao 1. Eles apresentaram uma media de idade de 10,5 e 16,5 anos no inicio e no final do tratamento ortodontico, respectivamente.

The nerve terminals of intrinsic muscular fibers of the tongue of adult wistar rats was studied by using silver impregnation techniques, transmission electron microscopy (TEM), and high resolution scanning electron microscopy (HRSEM) to observe the nerve fibers and their terminals. Silver impregnation was done according to Winkelman and Schmit, 1957. For TEM, small blocks were fixed in modified Karnovsky solution, postfixed in 1% buffered osmium tetroxide solution, and embedded in Spurr resin. For HRSEM, the parts were fixed in 2% osmium tetroxide solution with 1/15 M sodium phosphate buffer (pH 7.4) at 4°C for 2 h, according to the technique described by Tanaka, 1989. Thick myelinated nerve bundles were histologically observed among the muscular fibers. The intrafusal nerve fiber presented a tortuous pathway with punctiform terminal axons in clusters contacting the surface of sarcolemma. Several myelinated nerve fibers involved by collagen fibers of the endoneurium were observed in HRSEM in three-dimensional aspects. The concentric lamellae of the myelin sheath and the axoplasm containing neurofilaments interspersed among the mitochondria were also noted. In TEM, myofibrils, mitochondria, rough endoplasmic reticulum, Golgi's apparatus, and glycogen granules were observed in sarcoplasm. It is also noted that the sarcomeres constituted by myofilaments with their A, I, and H bands and the electron dense Z lines. In areas adjacent to muscular fibers, there were myelinated and unmyelinated nerve fibers involved by endoneurium and perineurium. In the region of the neuromuscular junction, the contact with the sarcolemma of the muscular cell occurs forming several terminal buttons and showing numerous evaginations of the cell membrane. In the terminal button, mitochondria and numerous synaptic vesicles were observed. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc.

Background: Data associating palatine mucosa, microvascular architecture, aging and diabetes mellitus are few, so the aim of the present study was to examine these conditions structurally and ultrastructurally. Methods: We used 18 female rabbits, aged about 2 years at the beginning of the experiment, distributed into 2 groups: aging diabetic and aging animals, prepared by three different methodologies: light microscopy, scanning electron microscopy and transmission electron microscopy. The samples were stained with hematoxylin-eosin for light microscopy, and for scanning electron microscopy, we used Mercox® Cl-2B vascular corrosion casts. For transmission electron microscopy, the specimens were fixed and embedded in Epon 812 resin. Results: Under light microscopy, we noted small amounts of underdeveloped connective papillae and significant flattened areas through the epithelium-connective tissue interface in the aging diabetic group. Larger blood vessels were deeply located in the palatine mucosa, branching off in the direction of the epithelium-connective tissue interface. Capillaries followed the interface contour. In both groups, vascular corrosion casts revealed capillaries sprouting out in disorganized rows but parallel between themselves. ‘Hair-pin’ capillary loops and convoluted capillary loops were noted. Conclusion: The aging diabetic group showed rarefying microvasculature areas with complex tortuous capillary loops. Transmission electron microscopy results showed that the aging diabetic group presented small cytoplasmatic projections directed to the vessel lumen and micropinocytic vesicle, i.e. caveolas. Epithelium-connective tissue interface, connective papillae, microangioarchitecture, and information about endothelial cells alterations were observed in the aging diabetic and aging animals.

Summary The aim of this study was to examine the microvasculature of the anterior and medium portions of the hard palatine mucosa in the adult gerbil ( Meriones unguiculatus ) using scanning electron microscopy. The vascular corrosion casts were obtained by injection of Mercox ® CL-2B synthetic resin and tissue corrosion was performed using sodium hydroxide solution. These casts revealed the presence of capillary loops in the palatine plicae and a smoother/flatter vascular network in the interplicae areas. The capillary loops consisted mainly of anteriorly oriented hair-pins and we also verified a differentiation in the shape of endothelial cell nuclei, which were elongated in arterial and circular in venous vessels.

The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae.

This research investigated the morphological, morphometric, and ultrastructural cardiomyocyte characteristics of male Wistar rats at 18 months of age. The animals were euthanized using an overdose of anesthesia (ketamine and xylazine, 150/10 mg/kg) and perfused transcardially, after which samples were collected for light microscopy, transmission electron microscopy, and high-resolution scanning electron microscopy. The results showed that cardiomyocyte arrangement was disposed parallel between the mitochondria and the A-, I-, and H-bands and their M- and Z-lines from the sarcomere. The sarcomere junction areas had intercalated disks, a specific structure of heart muscle. The ultrastructural analysis revealed several mitochondria of various sizes and shapes intermingled between the blood capillaries and their endothelial cells; some red cells inside vessels are noted. The muscle cell sarcolemma could be observed associated with the described structures. The cardiomyocytes of old rats presented an average sarcomere length of 2.071 ± 0.09 μm, a mitochondrial volume density (Vv) of 0.3383, a mitochondrial average area of 0.537 ± 0.278 μm(2), a mitochondrial average length of 1.024 ± 0.352 μm, an average mitochondrial cristae thickness of 0.038 ± 0.09 μm and a ratio of mitochondrial greater length/lesser length of 1.929 ± 0.965. Of the observed mitochondrial shapes, 23.4% were rounded, 45.3% were elongated, and 31.1% had irregular profiles. In this study, we analyzed the morphology and morphometry of cardiomyocytes in old rats, focusing on mitochondria. These data are important for researchers who focus the changes in cardiac tissue, especially changes owing to pathologies and drug administration that may or may not be correlated with aging.

The myotendinous junction (MTJ) is a major area for transmitting force from the skeletal muscle system and acts in joint position and stabilization. This study aimed to use trans- mission electron microscopy to describe the ultrastructural features of the MTJ of the sternomas- toid muscle in Wistar rats from newborn to formation during adulthood and possible changes with aging. Ultrastructural features of the MTJ from the newborn group revealed pattern during devel- opment with interactions between muscle cells and extracellular matrix elements with thin folds in the sarcolemma and high cellular activity evidenced through numerous oval mitochondria groupings. The adult group had classical morphological features of the MTJ, with folds in the sar- colemma forming long projections called ''finger-like processes'' and sarcoplasmic invaginations. Sarcomeres were aligned in series, showing mitochondria near the Z line in groupings between col- lagen fiber bundles. The old group had altered ''finger-like processes,'' thickened in both levels of sarcoplasmic invaginations and in central connections with the lateral junctions. We conclude that the MTJ undergoes intense activity from newborn to its formation during adulthood. With increas- ing age, changes to the MTJ were observed in the shapes of the invaginations and ''finger-like proc- esses'' due to hypoactivity, potentially compromising force transmission and joint stability. Microsc. Res. Tech. 75:1292-1296, 2012. V C 2012 Wiley Periodicals, Inc.

The microvascular system arrangement of the palatine mucosa in young rabbits was studied using vascular corrosion casts. Specimens were obtained by injecting low viscosity resin. Superficial microvessels were observed mainly by scanning electron microscopy (SEM). The blood microvessels showed differing features in the areas considered palatine rugae, inter-rugal areas and posterior region of the palatine raphe. Larger vessels were noted in deeper layers. Several capillary loops were distributed all over the palatine rugal surface. In spite of being a young animal, the rabbit's palatine mucosa demonstrated a complex angioarchitecture.

Objectives: Limbal stem cells (LSC) are self-renewing, highly proliferative cells in vitro, which express a set of specific markers and in vivo have the capacity to reconstruct the entire corneal epithelium in cases of ocular surface injury. Currently, LSC transplantation is a commonly used procedure in patients with either uni- or bilateral total limbal stem cells deficiency (TLSCD). Although LSC transplantation holds great promise for patients, several problems need to be overcome. In order to find an alternative source of cells that can partially substitute LSC in cornea epithelium reconstruction, we aimed at investigating whether human immature dental pulp stem cells (hIDPSC) would present similar key characteristics as LSC and whether they could be used for corneal surface reconstruction in a rabbit TLSCD model. Materials: We used hIDPSC, which co-express mesenchymal and embryonic stem cell markers and present the capacity to differentiate into derivative cells of the three germinal layers. TLSCD was induced by chemical burn in one eye of rabbits. After 30 days, the opaque tissue formed was removed by superficial keratectomy. Experimental group received undifferentiated hIDPSC, while control group only received amniotic membrane (AM). Both groups were sacrificed after 3 months. Results and conclusions: We have demonstrated, using immunohistochemistry and reverse transcription–polymerase chain reaction, that hIDPSCs express markers in common with LSC, such as ABCG2, integrin β1, vimentin, p63, connexin 43 and cytokeratins 3/12. They were also capable of reconstructing the eye surface after induction of unilateral TLSCD in rabbits, as shown by morphological and immunohistochemical analysis using human-specific antibodies against limbal and corneal epithelium. Our data suggest that hIDPSCs share similar characteristics with LSC and might be used as a potential alternative source of cells for corneal reconstruction.

Background: There is general consensus that the effects of intrinsic aging on the oral mucosa are relatively small, though potentially important to understanding the pathologies present in the aged animals. Objective: In this paper, the development of dorsal surface of rat tongue was examined using transmission electron microscopy (TEM) and high-resolution scanning electron microscopy (HRSEM) in order to understand the age-related structural and ultrastructural changes experimentally. Methods: In this study, we used female rats 75 and 720 days old (adult and aging). Tissues of rat tongue were prepared and the specimens submitted to HRSEM and TEM techniques. Results: The analysis of HRSEM and TEM demonstrated that the same characteristic keratinous epithelium was found in aging animals, however with some modifications. Conclusion: We agree that there are obvious changes in the oral mucosa with aging and these modifications can be observed starting from the ultrastructural aspects.

As características tridimensionais dos componentes intracelulares de células acinares e de ductos foram reveladas usando o método ósmio-DMSO-ósmio. As amostras foram maceradas em solução de tetróxido de ósmio diluído após a fratura na solução de dimetil sulfoxido. As lamelas do retículo endoplasmático granular são reveladas entremeadas por várias mitocôndrias. As lamelas do retículo endoplasmático granular são localizados ao redor dos núcleos na porção basal e estas estruturas são observadas em imagens tridimensionais de microscopia eletrônica de alta resolução.

Togue mucosa surface of 3-day postnatal rats was examined under transmission electron microscopy (TEM) and high-resolution scanning electron microscopy (HRSEM). For HRSEM analysis, the specimens were fixed in the same solution for 24 h, postfixed in 2% osmiun tetroxide, critical-point dried and coated with platinum-palladium. For TEM analysis, the specimens were fixed using modified Karnovsky solution and embedded in Spurr resin. The results revealed the presence of numerous microplicae in the membrane surface of keratinized epithelial cells to which groups of bacteria were attached. These bacteria were staphylococcus and coccus organized either in rows or at random, which were visualized in three-dimensional HRSEM images. At high magnification, the TEM images revealed the adhesion of bacteria to the cell membrane through numerous filamentous structures comprising the glycocalyx. The fine fibrillar structures rising from each bacterium and from cell membrane were clearly seen. These characteristics on bacteria structure may be used for future control or prevention of bacterial diseases and for installation of the oral native flora. A superfície lingual de ratos de três dias de idade foi examinada em microscópia eletrônica de transmissão (MET) e em microscópia eletrônica varredura de alta resolução (MEVAR). Para o método de MEVAR, os espécimes foram fixados na mesma solução por 24 h, pós fixados em solução de tetróxido de ósmio a 2%, secos em ponto crítico e cobertos com platina- paládio. Para análise em MET, os espécimes foram fixados utilizando-se solução de Karnovsky modificada e emblocadas em resina Spurr. Os resultados mostraram a presença de numerosas micropregas na membrana superficial das células epiteliais queratinizadas, nas quais estavam aderidos grupos de bactérias. Estas bactérias eram estafilococos e cocos, organizados em fileiras ou a esmo, e puderam ser observadas em imagens tri-dimensionais em MEVAR. Em maiores aumentos, as imagens em MET revelaram a adesão de bactérias nas células por meio de numerosas estruturas filamentares compondo o glicocálice. As delicadas estruturas filamentares na periferia das bactérias e das células foram nitidamente identificadas. Estas características da estrutura bacteriana podem ser utilizadas, no futuro, para controle e prevenção de doenças bacteriana, bem como para a instalação da flora oral nativa.

The aim of this study has been to determine the ultrastructural characteristics of the minor palatine salivary glands on the seventh day of development and to demonstrate wether their secretion is mucous, serous or seromucous by light, transmission and scanning electron microscopy. This study has shown that the palatine gland acinar cells are predominantly mucous with some serous units. These cells contain electron dense (serous) and low electron dense (mucous) granules in the apical portions. The cytoplasmatic organelles like mitochondria, Golgi apparatus and rough endoplasmic reticulum are localized in a supranuclear portion. We could also observe the flattened myoepithelial cells surrounding the basal part of the acini with myofilaments, Golgi apparatus and mitochondria. Desmosomal junctions and membrane interdigitations are present between the acinar and the myoepithelial cells. A basal lamina, divided in two layers, an electron dense and an electron lucent is present between the glandular stroma which is composed of dense connective tissue and the endpieces.

The three-dimensional angioarchitecture of young and aging rabbit tongues were studied using a vascular corrosion cast method. The vascular network of different lingual papillae were observed by scanning electron microscope (SEM). Young animals showed filiform papillae distributed all over considered area, with fungiform ones among them. In comparison to developed specimens, young rabbits demonstrated dense and higher organization of microvascular network.

The sensory nerve endings of the rat cheek mucosa were studied using the transmission electron microscopy. The specimens were fixed in modified Karnovsky solution and embedded in Epon resin. The sensory nerve endings showed a central terminal axon containing numerous mitochondria, neurofilaments, microtubules and clear vesicles. The proximal part of corpuscle revealed the cytoplasmic extensions of lamellar cells and the perineural cells. The fine bundles of collagen fibers are identified in the interlamellar spaces and the external part of corpuscle. Numerous concentric lamellae showed caveolae, interlamelar spaces filled with amorphous material, desmosome-type junctions between adjacent lamellae and the inner lamellar cells and the axoplasmic membrane. These fine structures are important to recognise and understand the morphological characteristics in the oral mucosa. As terminações nervosas sensitivas da mucosa da bochecha de ratos foram estudadas utilizando-se microscopia eletrônica de transmissão. As amostras foram fixadas em solução de Karnovsky modificada e inclusas em resina do tipo Epon. As terminaçãos nervosas sensitivas mostraram um axônio central terminal contendo numerosas mitocôndiras, neurofilamentos, microtúbulos e vesículas claras. A porção proximal dos corpúsculos revelaram projeções citoplasmáticas de células lamelares e células perineurais. Delgados feixes de fibras colágenas foram identificados nos espaços interlamelares e na região externa dos corpúsculos. Numerosas lamelas concêntricas apresentavam caveolas, espaços interlamelares preenchidos por material amorfo, desmossomos do tipo juncional entre lamelas adjacentes e células lamelares internas e membrana axolplásmatica. Essas estruturas delgadas mostram-se importantes na identificação e estudo das características da mucosa oral.

The dentin structure of non-erupted human deciduous mandibular and maxillary central and lateral incisor teeth was studied employing light and scanning electron microscopy. For light microscopy, nitric-acid-demineralized and ground sections were used. The sections were stained by hematoxylin-eosin, picrosirius and azo-carmim methods, and ground specimens were prepared using a carborundum disk mounted in a handpiece. For SEM study, teeth were frozen in liquid nitrogen and fractured at longitudinal and transversal directions. Structurally, demineralization and ground methods revealed tubules with primary and secondary curvatures, canaliculi, giant tubules, interglobular dentin, predentin, and intertubular dentin. Scanning electron microscopy showed three-dimensional aspects of dentinal tubules, canaliculi, peritubular dentin, intertubular dentin, and predentin. This study contributes to knowledge about dentin morphology showing characteristics of teeth not yet submitted to mastication stress. A estrutura de dentina de dentes incisivos decíduos central e lateral não erupcionados humanos de mandíbula e maxila foi estudada empregando os métodos de microscopia de luz e eletrônica de varredura. Para a microscopia de luz foram utilizadas a solução de ácido nítrico para a desmineralização e cortes espessos por desgaste. Os cortes foram corados pelos métodos de hematoxilina-eosina, picrosirius e azo-carmin e os cortes espessos foram preparados utilizando-se de disco de carborundum montado em caneta de mão. Para a microscopia eletrônica de varredura, os dentes foram fraturados transversal e longitudinalmente mediante a congelação em nitrogênio líquido. Os métodos de desmineralização e de desgaste em cortes espessos revelaram estruturalmente, túbulos dentinários com curvaturas priomarias e secundárias, canalículos, túbulos gigantes, dentina interglobular, predentina e dentina intertubular. A microscopia eletrônica de varredura mostrou os aspectos tridimensionais dos túbulos dentinários, canalículos, dentina peritubular, dentina intertubular, e predentina. Este estudo contribui para o conhecimento sobre a morfologia dentinária mostrando características de dentes não submetidos às forças mastigatórias.

A few papers have been related to young animal's angioarchitecture. This study tries to contribute to research about development of three-dimensional distribution in masticatory mucosa. The vascular corrosion casts were obtained using low viscosity resin - Mercox® CL-2B. We could note specific networks at dome of palatine rugae, inter-rugae areas and labial mucosa. Capillary loops were observed only at transverse palatine rugae Pocos trabajos han relatado la angioarquitectura de animales jóvenes. Este estudio contribuye con las investigaciones acerca de la distribución tridimensional de la mucosa palatina en conejos jóvenes usando MEB. La corrosión vascular del molde fue obtenida usando resina de baja densidad - Mercox® CL-2B. No pudimos observar redes específicas en la cúpula de los pliegues palatinos, en los interpliegues y mucosa labial. Fueron observados solamente loops capilares y pliegues transversos palatinos

Se analizaron tridimensionalmente las caracteristicas de la interfase del tejido epitelio-conectivo en la superficie de huellas dactilares de mono Cebus apella, empleando el microscopio electronico de barrido. El nucleo del tejido conectivo (NTC) y las papilas epiteliales se examinaron en las tres dimensiones. Las muestras fueron fijadas en solucion histologica Bouin para los preparativos y en Karnovsky modificada para examinar y observar en el microscopio electronico de barrido. Despues del tratamiento en solucion de NaOH al 10%, durante 3 a 5 dias, la superficie de las huellas dactilares revelaron una distribucion de NTC de lamina propia in situ mostrando imagenes en tres dimensiones originales con microscopio electronico de barrido. Las disposiciones lineal y circular del NTC estan claramente identificadas. Cada papila senalada presenta una gran base y la disposicion longitudinal de gruesos haces de fibras de colageno y, en algunas zonas con formaciones de un complejo reticular. Los surcos longitudinales entre las papilas senaladas mostraron una densa capa de tejido conectivo con NTC bajos o de forma laminar. La presencia de numerosos foramenes de las glandulas sudoriparas se observaron en tres dimensiones.

As características das células musculares e da junção miotendínea do músculo pterigóideo mediai de ratos adultos e com envelhecimento foram estudadas, empregando-se as técnicas de microscopia de luz e eletrônica de varredura e de transmissão. A microscopia de luz mostrou que as fibras musculares inserem-se na superfície óssea mandibular através de tecido colágeno composto por numerosos fibroblastos. Os cortes examinados sob luz polarizada revelaram a presença de fibras colágenas tipo\' e li\' nesta região. Além disso, puderam-se notar os capilares sangüíneos em grande número. Observações ao microscópio eletrônico de varredura ressaltaram as estriações presentes no músculo esquelético. O tecido conjuntivo que constitui o endomísio foi notado quando as amostras foram tratadas com solução de hidróxido de sódio e foi possível observar os diferentes diâmetros apresentados pelas fibras musculares. A microscopia eletrônica de transmissão evidenciou o alinhamento dos sarcômeros e as concentrações de mitocôndrias junto à lâmina basal na terminação da fibra muscular. O estudo da junção miotendínea dos ratos adultos e com envelhecimento identificou as fibras colágenas e os feixes de miofibrilas formando interdigitações que promovem o aumento da superfície de contato nesta região. Os aspectos observados nos músculos de ratos adultos mostraram-se bastante similares aos encontrados nos ratos com envelhecimento. The mediai pterygoid muscle cells and myotendinous junction characteristics of adult and aging rats were studied, using light microscopy and scanning and transmission electron microscopy techniques. The Iight microscopy showed the muscle fibers inserting in the mandible surface through collagen tissue and numerous fibroblasts. The samples examined in polarized light revealed the presence of type I and 11I collagen fibers in this site. Furthermore, the numerous blood capillaries could be noticed. Observations at the scanning electron microscope evidenced strias present in the skeletal muscle. The connective tissue that constitutes the endomysium could be noticed when the samples were treated with sodium hydroxide solution and it was possible to observe the muscle fibers different diameters. The transmission electron microscopy revealed the sarcomeres alignment and the mitochondria concentration by the basal lamina in the muscle fiber termination. The adult and aging rats myotendinous junction study showed the collagen fibers and the myofibrils bundles developing finger-like processes that increases the contact areas in this site. The aspects seen in adult rats pterygoid muscles were very similar to the ones seen in the aging rats.

Estudo das superfícies dorsal e ventral da língua e da superfície de interface epitélio-tecido conjuntivo de Bradypus torquatus, foi realizado empregando-se os métodos de microscopia de luz e microscopia eletrônica de varredura. As línguas de Bradypus torquatus foram removidas, dissecadas e seccionadas em 3 partes: rostral, média e caudal e tratadas pelos métodos de microscopia de luz e eletrônica de varredura. Os resultados revelaram que a língua apresenta um ápice arredondado, um corpo e uma raiz. A mucosa dorsal mostra três tipos de papilas linguais: filiformes, fungiformes e vaIadas e uma superfície inferior lisa. Histologicamente, observou-se que a superfície dorsal da língua contém as papilas filiformes, fungiformes e vaIadas, distribuídas nas regiões rostral, média e caudal. A camada epitelial é de espessura variável e possui os estratos basal, espinhosa, granular e córnea, mostrando as células epiteliais. A lâmina própria é caracterizada por um tecido conjuntivo denso formando as projeções papilares longas, curtas e arredondadas. As imagens tridimensionais obtidas pela microscopia eletrônica de varredura, mostraram numerosas papilas filiformes localizadas essencialmente nas regiões rostral e média. Poucas papilas fungiformes estão presentes na superfície dorsal da língua, tendo na maioria localizada nas margens da extremidade rostral da língua, exibindo as formas arredondadas e baixas. Elas são cobertas de células epiteliais queratinizadas. Na região caudal notou-se duas papilas vaIadas, contendo valas profundas e a superfície coberta de epitélio escamoso estratificado onde pode ser identificados poros gustativos. Nas papilas fungiformes identificou-se vários poros gustativos na superfície. As amostras tratadas com a solução de hidróxido de sódio e examinado ao microscópio eletrônico de varredura, revelaram após a remoção total da camada epitelial, o tecido conjuntivo denso em disposição original apresentando papilas conjuntivas de diferentes formas e tamanhos. As regiões rostral e média evidenciaram numerosas papilas correspondentes às filiformes e fungiformes e na região caudal, a papila conjuntiva da papila vaIada apresentou uma forma alongada. Na superfície foram notadas pequenos forames de ductos de glândulas salivares e projeções papilares maiores e menores em aspectos tridimensionais. Na superfície de interface epitélio-tecido conjuntivo, foram notados espessos feixes de fibras colágenas. Cortes corados por Picro-sírius e analisados por meio de microscopia de luz polarizada evidenciaram a coloração de papilas conjuntivas em aspecto vermelho indicando a presença de fibras colágenas do tipo I e fibras colágenas de coloração esverdeada, tipo III. The study of the dorsal and lingual surfaces and the surface of interface epithelium-connective tissue of Bradypus torquatus\'tongue was performed employing the light and scanning electron microscopy techniques. The tongue of Bradypus torquatus were removed, dissected and sectioned in three parts: rostral, medium and caudal regions and prepared by light and scanning electron microscopy methods. The results revealed that the tongue present a round apex, dorsum and a root. The dorsal mucosae showed three lingual papillae: filiforms, fungiforms and vallate and a ventral smooth surface. Histologically, it was observed that the dorsal surface of tongue contains the filiform, fungiform and vallate papillae located in the rostral, medium and caudal regions.The epitheliallayer is variable in thickness and possess the basal, spinosum, granular and queratinized layers, showing the epithelial cells. The lamina propria is characterized by a dense connective tis sue forming the long, short and rounded papilar projections. The three-dimensional images obtained by scanning electron microscopy, showed numerous filiform papillae located essentially in the rostral and medium regions. Few fungiform papillae are present in the dorsal surface of tongue, usually located in the border of rostral apex of tongue exhibiting the rounded and low in formo They are covered by queratinized epithelial cells. In the caudal region was noted two vallate papillae containing a deep vala and the surface was covered by stratified squamous epithelial cells. The superior third of surface of vallate papillae was covered by stratified squamous epithelial cells where may be identified the gustatory taste pores. In the fungiform papillae, several taste pores are located on the surface. The samples treated with NaOH solution and examined by scanning electron microscopy revealed afier removal of epitheliallayer, the dense connective tissue- in original disposition, presenting different sizes and shapes of conjuntive papillae. The rostral and medium regions envidentiated numerous papillae corresponding to the filiform and fungiform papillae and in the caudal region, the connective tissue papillae of vallate papillae presented a round formo On the surface were noted small foraminae of lingual salivary gland ducts and small and great papillary projections in three-dimensional images. AIso, on the surface of interface epithelium-connective tissue, were noted thick bundles of collagen fibers. The specimens stained with Picrosirius and examined by po larized light microscopy revealed the connective tissue stained in red colour indicating the collagen fibers type I and the type III, those stained in green colour collagen fibers.

Em nossos dias, a Cirurgia e Traumatologia Buco-Maxilo-Facial busca novas terapêuticas tendo como meta uma rápida reparação, osteointegração e regeneração dos tecidos ósseos e periodontais. Uma diminuição do tempo de reparação em fraturas e cirurgias ortognáticas, uma reparação normal de defeitos ósseos de tamanho crítico sem a utilização de enxertos e a redução do tempo de osteointegração de implantes possibilitará redução da morbidade, dos custos e uma reabilitação protética com menor período de tempo. Uma alternativa recente é a utilização de Fatores de Crescimento Semelhante a Insulina (IGFs) para a estimulação da proliferação e reparação tecidual. Os resultados observados na revisão de literatura indicam que as futuras terapias com IGFs propiciarão um avanço em relação à velocidade de reparação óssea, reparação em defeitos ósseos de tamanho crítico e em implantes imediatos. In our days, the Oral and Maxillofacial Surgery search new techniques to goal a quick repair, osteointeration and regeneration of bone and periodontal tissues. A diminution of time healing of bone fractures and ortognatic surgery, a normal healing in critics bone defects without grafts and a decrease time of osteointegration will make possible a low morbidity and a rapid protetic rehabilitation. An newly alternative is the use of Insulin Like Growth Factor (IGFs) to estimulate the tissue proliferation and healing. The results discovered in literature review indicate that future therapies with IGFs provide an advance in speed of bone healing, healing critical bone defects and immediate implants.

A parestesia é um distúrbio neurosensitivo causado por uma lesão no tecido nervoso. Ela tem uma incidência pouco freqüente após as cirurgias de terceiros molares inferiores; no entanto para o cirurgião dentista é de grande relevância. A literatura comenta sobre os tipos de lesão nervosa, causas e alternativas de tratamento não conservadores ligados à neuromicrocirurgia que são relacionados nesses casos. Nesse trabalho procurou-se estabelecer a classificação da lesão ao nervo alveolar inferior que ocorre nas exodontias de terceiros molares inferiores, entender os mecanismos fisiológicos, as causas principais que levam à ocorrência desse distúrbio e estudar as técnicas de neuromicrocirurgia, com suas indicações e contra-indicações para os tipos de lesão nervosa. Paresthesia consists of a neurosentitive disturb resulting from nerve tissue injury. It is less likely to occur following lower third molar surgeries, despite being highly relevant for dentists. The literature comments on the types of nerve injuries, its causes and related non-conservative treatment procedures involving neuromicrosurgery in such cases. This essay is an attempt to establish the types of nerve injury classification that occur following lower third molar surgery involving the inferior alveolar nerve, understand the physiological mechanisms, the main causes that result in such disturbance, and study the neuromicrosurgery procedures, their indications and non-indications concerning types of nerve injury.

INTRODUÇÃO: O desenvolvimento das glândulas salivares envolve um processo coordenado de interações moleculares complexas, nas quais as integrinas têm papel fundamental. As integrinas são uma família de receptores transmembrânicos, heterodímeros, compostos por duas subunidades: alfa e beta que estão ligadas de forma não covalente e dependentes de cations bivalentes. Estes heterodímeros medeiam sinais intra e extracelulares envolvidos na organização das células em tecidos e órgãos durante seu desenvolvimento. Em particular a integrina beta1 está envolvida na proliferação e diferenciação de células no desenvolvimento dos tecidos epiteliais. OBJETIVOS: Para compreender o papel da integrina beta1 no desenvolvimento das glândulas salivares humanas, estudamos a sua expressão por meio da hibridização in situ em tecido fetal humano em desenvolvimento. MATERIAL E MÉTODOS: A hibridização in situ com o método chromogenic in situ hibridization (CISH) foi utilizada para investigar a expressão genética da integrina beta1 em espécimes de glândulas salivares em desenvolvimento derivados de 30 fetos humanos em vários estágios gestacionais (de 825 semanas de vida intrauterina). Os resultados obtidos com a hibridização in situ foram relacionados com os aspectos morfológicos das glândulas salivares em desenvolvimento em cada fase da evolução da morfogênese glandular, por meio de análise qualitativa. RESULTADOS: Expressão da integrina beta1 foi detectada em raras células na fase prebotão. A expressão dessa molécula foi detectada em mais estruturas com a evolução do desenvolvimento morfogenético das glândulas salivares. CONCLUSÕES: A expressão a integrina beta1 parece ser regulada de forma temporoespacial e é associada ao estabelecimento do fenótipo maduro das glândulas salivares INTRODUCTION: Salivary gland development entails coordinated processes involving complex molecular interactions in which integrins have a fundamental role. The integrins are a family of heterodimeric transmembrane receptors comprising alpha and beta subunits that mediate intercellular and extracellular signals involved in the organisation of cells in tissues and organs during development. The beta1 integrin in particular have been implicated in proliferation and differentiation of cells involved in the development of epithelial tissues. OBJECTIVE: To understand the role of beta1 integrin in salivary gland development we have studied its expression in human foetal tissues. MATERIAL AND METHODS: In situ hybridisation CISH technique was used to compare the expression and localisation of integrin beta1 with differentiation markers in developing human salivary glands obtained from foetuses of 825 gestational weeks. RESULTS: Integrin beta1 first appeared during bud stage in a few cells and its distribution increased as salivary gland morphogenesis progressed. CONCLUSIONS: The developmentally regulated expression of integrin beta1 in association with the establishment of a mature phenotype of salivary glands is suggestive of its role in salivary gland morphogenesis

A ordem Cetacea compreende golfinhos e baleias, mamíferos totalmente adaptados ao ambiente aquático. A língua de duas espécies de cetáceos, Pontoporia blainvillei e Sotalia fluviatilis, foram utilizadas para descrição da morfologia das papilas linguais e da superfície de interface epitélio-tecido conjuntivo da lâmina própria, empregando as técnicas de microscopia de luz e eletrônica de varredura. As línguas foram fixadas e divididas em três porções: rostral, médio e caudal e processadas conforme os protocolos das técnicas utilizadas. A língua da Pontoporia blainvillei e Sotalia fluviatilis estava revestida por um epitélio estratificado queratinizado, sendo possível observar as camadas basal, espinhosa, granulosa e córnea. Pode-se notar que na língua, o tecido conjuntivo denso apresentava vasos sanguíneos e profundamente relacionado com o tecido muscular. A superfície de interface epitélio-tecido conjuntivo da lâmina própria apresentou papilas conjuntivas de várias formas. Elas correspondem às papilas filiformes e valadas, mostrando feixes de fibras colágenas em disposição original. Na microscopia de luz polarizada revelou-se fibras colágenas do tipo I e III. No terço médio e caudal de ambas as espécies foram encontradas ácinos de glândulas salivares. As amostras tratadas com solução de hidróxido de sódio, tiveram a camada epitelial removida, e as papilas conjuntivas foram observadas em aspecto tridimensional. Foi possível observar que a superfície dorsal de ambas as espécies é totalmente recoberta por papilas conjuntivas de aspecto filiforme. Observa-se também a presença dos forames dos ductos das glândulas salivares nas porções média e caudal da língua, sendo eles mais numerosos nos filhotes. Morfometricamente, as papilas conjuntivas apresentaram maior comprimento na espécie Sotalia fluviatilis do que na Pontoporia blainville. Foi observado somente na espécie Pontoporia blainvillei estruturas conjuntivas arredondadas na região média e caudal. Embora as áreas dessas estruturas tenham sido maiores na região caudal que na média, estatisticamente estes resultados não foram significativos (P>0,05). The Cetacea order comprises dolphins and whales, mammals totally adapted to the aquatic ambient. The tongue of two cetaceans species, Pontoporia blainvillei and Sotalia fluviatilis, was studied for description of the morphology of the lingual papillae and of interface epithelium the connective tissue surface, using the light and scanning electron microscopic techniques. The tongues were fixed and divided in three portions: rostral, medium and caudal and treated according to the protocols of techniques used. The tongues of the Pontoporia blainvillei and Sotalia fluviatilis were covered by keratinized stratified epithelium, being that is possible to verify the basal, spinosa, granular and cornetiel ayers. In the tongue the dense connective tissue of lamina propria showed blood vessels and muscular layer was deeply related. The interface epithelium-connective tissue surface of the lamina propria presented connective tissue papillae which are various in shape. They correspond to the filiform and vallate papillae showing the collagen fibers bunches in original disposition. In the polarized light microscopy revealed collagen fibers type I and III. In the medium and caudal third of both species various groupins of salivary gland acini. The samples treated with sodium hydroxide solution, the epithelial layer was removed and the connective tissue papillae were observed in three-dimensional SEM images. It was possible to observe that the dorsal surface of the both species is totally covered by connective tissue papillae of filiform aspect. We observed also the presence of the ducts of the salivary glands in the media and caudal portions of the tongue, being them more numerous in pups. Morphometric analysis showed that the connective tissue papillae presented larger length in the Sotalia fluviatilis than in the Pontoporia blainville samples. The round connectives structures in the media and caudal portions were observed only the Pontoporia blainvillei species. Although, the areas of those structures have been major in the caudal region than media, and these results were not signifficant (P>0,05).