Histopathological and histomicrobiological study of root canal therapy medication, comparison of calcium hydroxide versus gutta-percha with zinc oxide/eugenol in the teeth of dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anatomia comparada do lenho de Copaifera langsdorffii Desf. (Leguminosae-Caesalpinoideae) de floresta e cerradão

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mapeamento do biovolume de plantas aquáticas submersas a partir de dados hidroacústicos e imagem multiespectral de alta resolução

As plantas aquáticas têm papel fundamental no equilíbrio dos ecossistemas, porém seu crescimento desequilibrado pode obstruir canais, represas e reservatórios e afetar múltiplos usos da água. em relação a plantas aquáticas submersas, a utilização de medidas de controle torna-se mais complexa, em face da dificuldade em mapear e quantificar volumetricamente as áreas colonizadas. Nessas situações, considera-se que o uso de dados hidroacústicos possibilite o mapeamento e a mensuração dessas áreas, auxiliando na elaboração de propostas de manejo sustentáveis desse tipo de vegetação aquática. Assim, o presente trabalho utilizou dados acústicos e a técnica de krigagem para realizar a inferência espacial do biovolume de plantas aquáticas submersas. Os dados foram obtidos em três levantamentos ecobatimétricos realizados em uma área de estudos localizada no rio Paraná, caracterizada por condições favoráveis para proliferação de vegetação aquática submersa e dificuldade de navegação. Para delimitar as áreas caracterizadas pela presença de plantas aquáticas submersas, utilizou-se uma imagem multiespectral de alta resolução espacial World View-2. O mapeamento do biovolume das plantas aquáticas submersas nas áreas de ocorrência do fenômeno foi realizado a partir da inferência do biovolume por krigagem e do fatiamento dos valores inferidos em intervalos de 15%. A partir do mapa gerado, foi possível identificar os locais de maior concentração de macrófitas submersas, com predominância de valores de biovolume entre 15-30% e 30-45%, confirmando a viabilidade da utilização da krigagem na inferência espacial do biovolume, a partir de medidas ecobatimétricas georreferenciadas e com o suporte de imagem de alta resolução espacial.

Engenharia nos sertões nordestinos: o Gargalheiras, a Barragem Marechal Dutra e a comunidade de Acari, 1909-1958

In Brazil, between the late nineteenth and early decades of the twentieth, polytechnic engineers assumed an important role in discussing the establishment of a modern country. The problem of drought in northeastern Brazil gave the professionals performance, within an interventional process more mounts, the conception plans and measures for the purposeful integration of the territory afflicted. With the foundation of Inspetoria de Obras Contra as Secas (IOCS), in 1909, the actions to combat drought and would be institutionalized, them, studies performed out by technical and scientific committees would be systematically applied in the Brazilian Northeast. So, This work was central objective understand the historical process inplantation of a whole infrastructure of modern character by professional technical and their consequences within the Northeast Geographic space, in specific, in the municipality of Acari in the State of Rio Grande do Norte, in the first half of the twentieth century. The politics of the government, through technical education and scientific engineers polytechnics, would emphasize, during the twentieth century, the building of dams, and irrigation canals, wells, railways, highways, between other elements, that would soon transform the physical space-northeast, specifically, the territory acariense. These works began to contribute to the setting of man backcountry their land, promote the regular practice of agriculture even in periods of drought and, the integration, especially, economic of territory acariense the other producing regions of Rio Grande do Norte and the Northeast as well as promoting the modification of the landscape of the world backcountry. These actions functioned as elements of modernity and progress that transformed the space by favoring by favoring the formation of urban networks (urban) in this space

Vicus Judæorum: os judeus e o espaço urbano no Recife neerlandês

This work broaches the participation of the Jewish community in the urban expansion of Recife, Brazil, during the Dutch period (1630-1654). With the arrival of the Dutch, the village of Olinda, former capital of Pernambuco, was destroyed and Recife received the juridical statute of city (stad), becoming the capital of Dutch Brazil or New Holland. It became the main West Indians Company s entrepot in South Atlantic, serving as naval base, port of call for ships, and point of export of the sugar production of Pernambuco, and import of European goods and African slaves. In order to such administrative, military and economic functions be carried out, the sand isthmus where Recife used to stay, and the fluvial island of Antônio Vaz, received improvements of many sort. The Dutch hydraulic technology was put in practice, with a posture of opposition between civilization and nature. Among military works and production of urban equipments, the rivers shores were land-filled, canals were built, bridges were lifted, and hundreds of buildings were erected. The civil Dutch population of Recife engaged in the process of production of physical space, which brought a sense of collective action towards the formation of the urban, or burgher, community. From the physical to the social space, there was an effort towards Dutch cultural standards in the urban environment. The Zur Israel Jewish community, formed by private civilians, it is, nonemployees of the WIC, engaged in those processes. It produced physical space through the land-filling and improvement of non healthy areas, and was also responsible for the construction of a significant section of the town s buildings and some of urban equipments, such as stores, markets and slave-warehouses, making more dynamic their economical activities. But their social traffic was due to the adaptation of their behavior to the standards of Dutch sociability. Thus, the community body made itself part of the social body. Disposing of internal selfregulation, it produced spaces with their cultural references cemetery, synagogue, texts enjoying benefits of the government. Zur Israel inscribed itself in the universal history of the Jews as the first community of Americas, and had a fundamental part on the emancipation of Jews within Western society

Comprovação da real comunicação entre o endodonto e o periodonto através do canal cavo inter-radicular e sua prevalência em molares inferiores humanos

The neurovascular system of the pulp and of the periodontium is interconnected and among the possible intercommunications between these two tissues, there is the cavo inter-radicular canal. It is a small canal that goes through any inter-radicular dentine and arises in the furca region of the multi-radicular teeth. Its predominance has been studied in the literature, by several methodologies, with divergent results. The objective of this work was to establish, in vitro, the predominance of the cavo inter-radicular canal, in human lower molars, through the diaphanization technique and dye leakage. For this research, 140 teeth (100 first and second 40 lower molars) were selected, extracted due to different reasons, belonging to a teeth bank of the Endodontics discipline of the Dentistry College at Federal University of Rio Grande do Norte. The teeth were preserved in formol until the moment of use and immersed in physiological solution. Had the endodontic access fulfilled and the whole external surface, except for the furcation, sealed with two layers of nail enamel. The cleaning of the pulpar chamber floor was carried out with sodium hypochlorite solution 5%, being this solution renewed every 5 minutes, during 1 hour. The teeth were immersed in Indian dye and, after drying of the dye, they had their crowns split up in the amelo-cemental junction. Then, they were examined in a stereomicroscope, where marks of the coloring were observed in the furcation and on the pulpar floor. After this recording, the sample was diaphanized and with the transparent teeth, it was possible to observe in the stereomicroscope, the true inter-radicular canals. As a result of this experiment, the presence of these canals was observed in 13 % of the first and 7, 5 % of the second evaluated molars. The study showed that both the presence of the cavo inter-radicular canal is real and the diaphanization and dye leakage is an efficient method for this type of research

Controle democrático no capitalismo contemporâneo: limites e contradições

This study examines the determinations of the structural crisis of capital in the democratic control effected on the councils of rights and policies. Therefore the research aimed to apprehend and analyze the conjunctural and structural determinations and cyclical changes that incide on democratic control established by the Federal Constitution of 1988. The specific objectives turned to: (1) identify and analyze the theoretical and political fundamentals of democratic control in the production of social service in ENPESS 2010, in the productions of CFESS and the journal social services and society, (2) apprehend and analyze the possibilities, limits, contradictions and social direction of democratic control in contemporaneity and (3) identify and analyze the major political forces that constitute support and opposition to the exercise of democratic control. To approximate to the intended objectives the way theoretical and methodological covered was based in a perspective of totality that allows the apprehension of the object of study in their contradictory dimensions of universality, particularity and singularity. The results enabled to develop critical analysis of theoretical production of the Brazilian social service on the subject, having as snip studies of the journals social service and society; works of ENPESS 2010 and CFESS positioning. It was found, so in analysis undertaken, the spaces of democratic control suffer inflections of capital that shape their practices and social direction. In theoretical productions chosen, identified the prevalence of democratic control studied under an endogenous perspective to participatory canals, with incipient connections to the structural/conjunctural determinations of a historical period of crisis and seeks to restore the hegemony of capital. The positioning of the CFESS tends to recognition of democratic control in its contradictory dynamics recognizing the limits imposed by the sociability of the capital at the present time

Avaliação da eficiência da técnica de obturação pela compressão hidrùlica vertical após instrumentação automatizada

The purpose of this study was to evaluate through radiographic and microscopic analysis the efficiency of the filling techniques by vertical hidraulic compression after the root canal mechanical instrumentation in vitro as well to evaluate the marginal apical leakage through macroscopic and microscopic analysis. Thirty human mandibular molars were used , they were divided on three groups, these were subdivided on six subgroups with five specimens each, come down to 106 root canals filled. Initially, the teeth were instrumented with Profile system series 29 and filled with two ways: single accessory cone or single cone associated with gutta-percha secundary cone, with Fill Canal sealer or Sealer 26. Completed the filling, the teeth were coated with araldit and finger -nail polish except for the apical 2 mm and dried for 3 hours, thep radiographs were taken of the teeth in orto and disto-radiai directions. Next, the coronal seal was carried out with composite resin photopolymerized and with their process of making impermeable. Teeth of positive controls were used without araldit and finger-nail polish whereas the negative controls were used with total coat of araldit and finger-nail polish. The specimens were placed in 2% Methylene Blue dye for 24 hours and thermocycled for 7 days. Afterwards, sections were made of each tooth at mesial and distal roat, after this the teeth were radiographed at buccolíngual direction for a macroscopic analysis and at buccolingual and mesiodistal directions for assessment of the marginal apical leakage. Cross sections were made 3 mm to 3mm since the tooth apice. The sections obtained for each group were observed with a stereomicroscope to evaluate the quality of the root canal filling and the marginal apical leakage. The results showed that: In the four techniques the marginal dye leakage was present in the apical third; in all groups the quality of the root canal filling in the radiography was better at mesial root canal and the single cone technique showed inefficient when only a single distal root canal was present. In the radiographic evaluation the best quality of the root canal filling was observed in the 1A group (single accessory cone + FiIl Canal), as in the mesial root as in the distal root wich Shcwed twe root canals: when the distaI root had only one canal. the best result was showed by 28 group (single accessory cone associated with secundary cone + Fill Canal) In the macroscopic analysis of longitudinal !eaKage (outside surface). less leakage was showed as In the mesial root as in the distal root in the negative control group (3) followed 2A group (single accessory cone + Sealer 26). When the microscopic analysis of tranversal leakage of both roots (inside surface) was carried out. the groups that showed less dye leakage were the negative control (38) followed the 28 group (single acessory cone associated with secundary cone + Sealer 26). The homogeneity o filling was best noted in the 1 A group (.single accessoty cone + Fill Canal). The groups that showed less dye penetration in the tranversal leakage (total area) were negative control (3B) and 2B

Chlorhexidine induces DNA damage in rat peripheral leukocytes and oral mucosal cells

Objective: Chlorhexidine digluconate is widely used in dental practice for decreasing plaque control, controlling gingivitis and disinfecting root canals. However, the undesirable effects of chlorhexidine digluconate regarding its genotoxicity are conflicting in the literature. Thus, the aim of this study was to investigate the genotoxicity of chlorhexidine digluconate in rat peripheral blood and oral mucosal cells by the single cell gel (comet) assay and micronucleus assay.Methods: Thirty male Wistar rats were distributed into three groups: negative control; experimental group orally treated with 0.5 ml of 0.12% chlorhexidine digluconate, twice daily, during 8 days; and positive control, which received 4-nitroquinoline 1-oxide at 0.5 g/l by drinking water.Results: A statistically significant increase of DNA damage was observed in leukocytes and oral mucosal cells of the chlorhexidine digluconate treated group, as assessed by the comet assay. However, no increase of micronucleated cells was detected in reticulocytes from peripheral blood cells.Conclusions: Taken together, the data indicate that chlorhexidine digluconate is able to induce primary DNA damage in leukocytes and in oral mucosal cells, but no chromosome breakage or loss in erythrocytes.

Healing process of incisor teeth of diabetic rats replanted after storage in milk

Several local factors that influence the healing process of replanted teeth have been investigated. However, it remains unclear how systemic alterations, such as diabetes mellitus, affect the prognosis of these cases. The purpose of this study was to evaluate the healing process of incisors of non-controlled diabetic rats replanted after storage in bovine long shelf-life (UHT) whole milk. Thirty-two rats were randomly assigned to receive an endovenous injection of either citrate buffer solution (group I - control; n = 16) or streptozotocin dissolved in citrate buffer solution to induce diabetes (group II; n = 16). After confirmation of the diabetic status by analysis of the glycemic levels, the maxillary right incisor of each animal was extracted and immersed in milk for 60 min. The root canals of teeth were then instrumented, and were filled with a calcium hydroxide-based dressing and replanted into their sockets. All animals received systemic antibiotic and were killed by anesthetic overdose 10 and 60 days after replantation. The specimens containing the replanted teeth were removed, fixed, decalcified, and embedded in paraffin. Semi-serial 6-mu m-thick sections were obtained and stained with hematoxylin and eosin for histologic and histometric analyses. The results showed that the connective tissue adjacent to the root surface was less organized in the diabetic animals than in the control animals in both periods; the root dentin was less severely affected by root resorption in the diabetic rats; there were no significant differences between the control and diabetic groups regarding the occurrence of replacement resorption and inflammatory resorption.

Use of vitamin C in delayed tooth replantation

O objetivo deste trabalho foi avaliar microscopicamente, em reimplantes tardios de dentes de rato, os efeitos do tratamento da superfície radicular com diferentes soluções. Foram utilizados 30 ratos Rattus norvegicus albinos da linhagem Wistar que tiveram seus incisivos centrais extraídos e deixados sobre a bancada por 6 h. As polpas foram extirpadas e os canais irrigados com solução de hipoclorito de sódio a 1%. Após o preparo endodôntico, a superfície radicular de cada dente foi tratada com solução de hipoclorito de sódio a 1% por 10 min (trocada a cada 5 min) seguida de soro fisiológico por 10 min, e os dentes foram divididos em três grupos com 10 espécimes em cada um. Nos Grupos I, II e III, respectivamente, a superfície radicular foi tratada com fluoreto de sódio fosfato acidulado a 2%, vitamina C e vitamina C efervescente (2 g, Redoxon®). Após obturação com pasta de hidróxido de cálcio os dentes foram reimplantados e os animais foram sacrificados aos 10 e 60 dias. O Grupo I apresentou maiores áreas de reabsorção por substituição e anquilose. Comparando as formas de vitamina C utilizadas, a efervescente (Grupo III) foi a que apresentou resultados mais favoráveis com mais áreas de anquilose e reabsorção por substituição que áreas de reabsorção inflamatória.

Tooth replantation after use of euro-coffins solution or bovine milk as storage medium: a histomorphometric analysis in dogs

Purpose: Euro-Collins solution was developed for the preservation of organs for transplantation, whose characteristics have raised interest for its use as a storage medium for avulsed teeth before replantation. This study evaluated histologically and morphometrically the healing process of dog teeth replanted after storage in Euro-Collins solution or bovine milk.Materials and Methods: Eighty roots of 4 young adult mongrel clogs were randomly assigned to 4 groups (n = 20) and the root canals were instrumented and obturated with gutta-percha and a calcium hydroxide-based sealer. After 2 weeks, the teeth were extracted and subjected to the following protocols: GI (negative control), replantation immediately after extraction; GII (positive control), bench-drying for 2 hours before replantation; GIII and GIV, immersion in 10 mL of whole bovine milk and Euro-Collins solution at 4 C, respectively, for 8 hours before replantation. The animals were sacrificed 90 days postoperatively. The pieces containing the replanted teeth were subjected to routine processing for histologic and histometric analyses under light microscopy and polarized light microscopy.Results: Root resorption was observed in all groups. GII exhibited the greatest loss of dental structure (P < .01), and inflammatory resorption was predominant in this group. Storage in milk showed poorer results than immediate replantation and storage in Euro-Collins solution (P < .01). The teeth stored in Euro-Collins solution presented similar extension of root resorption and periodontal ligament reorganization to those of immediately replanted teeth.Conclusions: The findings of this study suggest that the Euro-Collins solution is an adequate storage medium for keeping avulsed teeth for up to 8 hours before replantation.

Calcium Hydroxide Mixed With Camphoric p-Monochlorophenol or Chlorhexidine in Delayed Tooth Replantation

This study evaluated the repair process after delayed replantation of rat teeth, using calcium hydroxide (Ca(OH)(2)) mixed with camphorated p-monochlorophenol (CMCP), chlorhexidine 2% (CHX), or saline as temporary root canal dressing to prevent and/or control inflammatory radicular resorption. Thirty Wistar rats (Rattus norvegicus albinos) had their right upper incisor extracted, which was bench-dried for 60 minutes. The dental papilla, the enamel organ, the dental pulp, and the periodontal ligament were removed. The teeth were immersed in 2% acidulated-phosphate sodium fluoride solution for 10 minutes. The root canals were dried with absorbent paper cones and divided into 3 groups of 10 animals according to root canal dressing used: group 1: Ca(OH)(2) + saline, group 2: Ca(OH)(2) + CMCP, and group 3: Ca(OH)(2) + CHX 2%. Before replanting, the teeth sockets were irrigated with saline. Histological analysis revealed the presence of inflammatory resorption, replacement resorption, and ankylosis in all 3 groups. Statistical analysis showed a significant difference between group 3 and the other groups. The use of Ca(OH)(2) mixed with CMCP or CHX did not show an advantage over the use of Ca(OH)(2) mixed with saline in preventing and/or controlling inflammatory resorption in delayed replantation of rat teeth.

Effect of calcium hydroxide-based materials on periapical tissue healing and orthodontic root resorption of endodontically treated teeth in dogs

This study evaluated periapical tissue healing and orthodontic root resorption of endodontically treated teeth sealed with calcium hydroxide in dogs. The sample consisted of three contralateral pairs of maxillary incisors and two contralateral pairs of mandibular incisors in each of two dogs using a split mouth design. After biomechanical preparation of the teeth in the first group (n = 10), a Ca(OH)(2) dressing was placed for 14 days before root canal filling with Ca(OH)(2)-based sealer (Sealapex) and gutta-percha points. In the second group (n = 10), root canals were obturated immediately after the mechanical preparation with gutta-percha points and zinc oxide and eugenol (ZOE)-based sealer (Endofill). After completion of endodontic treatment, the teeth were moved with an orthodontic appliance with a calibrated force of 200 g, reactivated every 21 days. After 105 days, the animals were killed and the teeth were removed upon completion of active treatment, without a period of recovery, and prepared for histomorphological analysis. All sections of each tooth were graded subjectively on a scale from one to four to obtain the average of the 16 histomorphological parameters analysed. Evaluation of the differences between the two treatment protocols was made with Mann-Whitney U-test. It was observed that the teeth treated with Ca(OH)(2)-based materials provided better outcomes (P = 5%), with complete repair of all root resorption areas, high rate of biological closure of the main canal and apical accessory canals by newly formed cementum, less intense and extensive chronic inflammatory infiltrate, and better organization of the periodontal ligament. Under the tested conditions, Ca(OH)(2)-based materials had a favourable action on periapical tissue healing and repair of orthodontic root resorption in endodontically treated dogs' teeth.

Propolis as storage media for avulsed teeth: microscopic and morphometric analysis in rats

The maintenance of the avulsed teeth in appropriate media for preserving the cellular viability has been important for repairing the periodontal ligament and preventing the root resorption after tooth reimplantation. Propolis is a substance capable of preserving cellular viability. This study aimed to analyze the propolis substance as a storage media for maintaining the avulsed teeth, besides to determine the ideal time period for keeping the tooth inside it. Thus, 60 maxillary right central incisors of rats were extracted and divided into five groups. In groups I and II, teeth were kept in propolis for 60 min and 6 h, respectively; in group III, teeth were kept in milk for 6 h; in group IV, teeth were kept dry for 60 min; and in group V, they were immediately reimplanted. All teeth had their root canals filled with calcium hydroxide paste. Following, teeth were reimplanted in their sockets. After 15 and 60 days, animals were killed and the obtained samples were processed in laboratory for microscopic and morphometric analyzing. The results showed that the occurrence of inflammatory resorption, dental ankylosis and the formation of the connective tissue parallel to the root surface were similar among groups. It could be verified a greater occurrence of replacement resorption in group IV when comparing to other groups. In groups I and IV, the presence of periodontal ligament-like connective tissue was substantially smaller than the other groups. Regarding to the cementum amount over the root, it could be observed that this was present in smaller amount in groups I and IV. Group II was similar to groups III and IV. Therefore, according to the results of this study, the use of propolis as a storage media for maintaining avulsed teeth could be highlighted, and the 6-h period was more appropriate than the 60-min period.