Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-03-23T15:01:59Z No. of bitstreams: 1 TES_HELENA_FETTER_FILIPPINI_PARCIAL.pdf: 1312432 bytes, checksum: dda78ca2fa347004234d72add7b38398 (MD5) / Made available in DSpace on 2017-03-23T15:01:59Z (GMT). No. of bitstreams: 1 TES_HELENA_FETTER_FILIPPINI_PARCIAL.pdf: 1312432 bytes, checksum: dda78ca2fa347004234d72add7b38398 (MD5) Previous issue date: 2017-01-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The central and peripheral mechanisms involved in pulpal pain are still unclear. This study compared, initially, the chronic pulpitis model evoked by the application of complete Freund's adjuvant (CFA) into the pulps of rats, with other models of pulpitis. For this purpose, the pulps of the left upper first molars of Wistar rats were accessed. There were four experimental groups according to the surgical procedure: open, closed, CFA and na?ve. Behavioral changes, as well as, body weight gain and food and water consumption, were evaluated at different experimental times (1, 2, 3 and 8 days). After euthanasia, blood, brain and trigeminal ganglion (TG) samples were collected for further analysis. All experimental groups with pulp acess had a decrease in body weight gain (for up to 3 days). A reduction in food consumption was observed in all the groups with pulp exposure, on the first day. The CFA group showed a significant reduction of locomotor activity (at 1 and 3 days), which was associated with increased satellite glial cells activation in the ipsilateral TG. Activation of astrocytes in the amygdala was not affected in the studied groups. The second part of this study investigated the relevance of Toll-like receptor 4 (TLR4) activation in the acute pulpitis caused by the application of the transient receptor potential ankyrin-1 (TRPA1) mustard oil (MO), into the rat pulps. Preliminary studies were performed to compare the sensorimotor activity of the masticatory muscles with the application of lipopolysaccharide (LPS) or MO in the dental pulp. The model using MO application into the pulp of rats was selected, because of the marked increase of the electromyographic activities evoked by this agent, when compared to LPS. The animals received a intrathecal (i.t.) pre-treatment with the TLR4 LPS-RS antagonist (25 ?g / 10 ?l) or saline solution (10 ?l) (vehicle group), 10 min before pulp application of MO. For this purpose, a stereotaxic surgery was performed to access the trigeminal subnucleus caudalis. Changes in electromyography activity (EMG) of masticatory muscles were recorded for 15 min after the MO application into the pulp. The trigeminal caudalis subnucleus was removed after euthanasia, for evaluation of TLR4 expression by western blotting analysis. Changes in EMG activity in anterior digastric muscles were significantly reduced by the intrathecal administration of LPS-RS in the trigeminal subnucleus caudalis (p ?0.05). The data obtained suggest the participation of satellite glial cells in the chronic pulpitis model induced by CFA, as well as, TLR4 receptors in the acute pulpitis model caused by MO application into the rat pulps. Altogether, the present results shed new light on the mechanisms underlying acute and chronic tooth pulp inflammatory pain. / Os mecanismos centrais e perif?ricos envolvidos na dor pulpar ainda n?o est?o totalmente claros. O presente estudo comparou, inicialmente, o modelo de inflama??o pulpar cr?nica induzido pela aplica??o de adjuvante completo de Freund (CFA), em polpas de ratos, com outros modelos de pulpite. Para tanto, as polpas dos primeiros molares superiores esquerdos de ratos Wistar foram acessadas. Foram criados 4 grupos experimentais conforme a abordagem pulpar: aberto, fechado, CFA e na?ve. As altera??es comportamentais, bem como, o ganho de peso corporal e o consumo de ?gua e ra??o, foram avaliados em diferentes tempos experimentais (1, 2, 3 e 8 dias). Ap?s a eutan?sia, amostras de sangue, c?rebro e g?nglio trigeminal (GT) foram coletadas para an?lises posteriores. Todos os grupos experimentais com exposi??o da polpa apresentaram diminui??o do ganho de peso corporal (at? o 3 ? dia). A redu??o do consumo de ra??o foi observada em todos os grupos no primeiro dia. O grupo CFA mostrou redu??o significativa na atividade locomotora (em 1 e 3 dias), que foi associada ao aumento da ativa??o das c?lulas sat?lites da glia no GT ipsilateral. A ativa??o de astr?citos na am?gdala n?o foi afetada nos grupos estudados. A segunda parte deste estudo investigou a participa??o do receptor Toll-like 4 (TLR4), na media??o da pulpite aguda causada pela aplica??o de ?leo de mostarda (OM), um agonista de receptores de potencial transit?rio anquirina-1 (TRPA1), em polpas de ratos. Estudos preliminares foram realizados comparando a atividade sensoriomotora dos m?sculos mastigat?rios diante da aplica??o de lipopolissacar?deo (LPS) ou OM na polpa dent?ria. O modelo utilizando OM na polpa de ratos foi escolhido, devido ao aumento marcante das atividades eletromiogr?ficas (EMG), quando comparado ao LPS. Os animais foram pr?-tratados por via intratecal (i.t.) com o antagonista seletivo dos receptores TLR4, o LPS-RS (25 ?g/10 ?l, 10 min antes da aplica??o pulpar de OM. O grupo controle recebeu solu??o salina (10 ?l) (grupo ve?culo), pela mesma via, no mesmo tempo de administra??o. Para tal, foi realizada uma cirurgia esterot?xica para permitir o acesso ao subn?cleo caudal trigeminal. As altera??es das atividades de EMG dos m?sculos mastigat?rios foram registradas durante 15 min ap?s a aplica??o de OM na polpa. O subn?cleo caudal trigeminal foi removido ap?s a eutan?sia, para avalia??o da express?o de TLR4, atrav?s da an?lise de western-blotting. As altera??es da atividade de EMG nos m?sculos dig?stricos anteriores foram significativamente reduzidas pela administra??o intratecal de LPS-RS no subn?cleo caudal do trig?meo (p?0,05), indicando um papel relevante para esses receptores nos mecanismos de sensibiliza??o central, ap?s a aplica??o de OM. O conjunto de dados obtidos sugerem a participa??o das c?lulas sat?lites da glia no modelo de pulpite cr?nica induzida por CFA, bem como, dos receptores TLR4 no modelo de pulpite aguda provocada pela aplica??o de OM em polpas de ratos. Essas evid?ncias contribuem para o melhor entendimento dos mecanismos relacionados com a transmiss?o da dor pulpar aguda e cr?nica.

Made available in DSpace on 2015-04-14T13:30:25Z (GMT). No. of bitstreams: 1 434616.pdf: 1582052 bytes, checksum: cc637f53364c5652d47a360c1e06850b (MD5) Previous issue date: 2011-09-21 / Different approaches have been advocated for implementation of conservative treatment of the pulp tissue, usually employing inflammation control and the application of compounds with therapeutic potential on the pulp. The Resolvin E1 (RvE1) is a lipid mediator capable of regulating inflammatory routes that do not involve the blockage of enzymatic intermediates. The aim of this study was to evaluate the effect of the topical application of RvE1 on dental pulps exposed to the oral environment. To this end, 42 male Wistar rats (n=6 per group/period) had the pulps of the right mandibular first molars assessed and then left exposed to the oral environment for 24 hours. After this period, topical medication either with 0.1% ethanol (vehicle of RvE1), RvE1 or a corticosteroid was applied onto the pulp tissue, and the teeth were then sealed with silver amalgam. The effects of the tested protocols were assessed by histology after 24 and 72 hours. Untouched teeth were used as reference for relative analysis and grading of the alterations observed in test groups. RvE1 induced significant reduction and containment of pulp inflammation with less extensive damage compared to either 0.1% ethanol or corticosteroid (P<0.05). Within the conditions tested none of the tested drugs promoted identical pulp tissue features compared to the observed in untouched teeth (P<0.01). The results presented herein have uncovered protective roles for RvE1 in pulp inflammation, suggesting that it may be a candidate for a novel therapeutic strategy for preservation of its vitality. / Diferentes abordagens t?m sido advogadas para implementa??o do tratamento conservador do tecido pulpar, usualmente empregando o controle da inflama??o e a aplica??o de compostos com potencial terap?utico sobre a polpa. A Resolvina E1 (RvE1) ? um mediador lip?dico capaz de regular rotas inflamat?rias que n?o envolvem o bloqueio de intermedi?rios enzim?ticos. O objetivo deste estudo foi avaliar o efeito t?pico da RvE1 sobre polpas dentais expostas ao meio oral. Para esta finalidade, 42 ratos machos Wistar (n = 6 por grupo/per?odo), tiveram as polpas dos primeiros molares inferiores direitos acessadas e deixadas expostas ao meio oral por 24 horas. Ap?s este per?odo, medica??o t?pica com etanol 0.1% (ve?culo da RvE1), RvE1 ou corticoster?ide foi aplicada sobre o tecido pulpar e os dentes foram selados com am?lgama de prata. Os efeitos dos protocolos testados foram avaliados histologicamente ap?s 24 e 72 horas. Dentes intactos foram utilizados como refer?ncia para an?lise das altera??es verificadas nos grupos experimentais. RvE1 induziu significativa redu??o e conten??o da inflama??o com danos pulpares menos extensos em compara??o ao etanol 0.1% ou corticoster?ide (P<0.05). Nenhum dos f?rmacos testados promoveu caracter?sticas pulpares id?nticas ?s observadas nos dentes intactos (P<0.01). Os resultados apresentados revelaram a fun??o protetora da RvE1 na inflama??o da polpa, sugerindo que ela possa ser candidata para uma nova estrat?gia terap?utica para a preserva??o de sua vitalidade.

Made available in DSpace on 2015-04-14T13:30:33Z (GMT). No. of bitstreams: 1 458701.pdf: 1213511 bytes, checksum: 5c4a01085ee74091dcd6f5af755a1eca (MD5) Previous issue date: 2013-11-29 / Studies on dental caries demonstrate inflammation on dental pulp tissues following infection. Cytokines are able to activate those cells linked to inflammatory and immune response thus neutralizing potentially aggressive agents and allowing tissue repair. Some of those cytokines, denominated chemokines, could contribute to the establishment of an immunotherapy able to control those cytokines involved with the triggering of dental pulp inflammation. Research on chronic inflammation has provided some relevant insights. However, the role of certain chemokines on acute inflammation is yet not conclusive. This study attempts to unveil the role of the chemokines CCL5/RANTES, CCR5 and RANKL on initial and acute pulpal inflammation. Methods: 18 Wistar rats were subjected to anesthesia. Access was performed on their first lower molars until pulp exposure. They were divided into three experimental groups considering the solution administered: Saline, lipopolysaccharide (LPS) and lipoteichoic acid (LTA) (n=6 each group). Higid second lower molars were used as controls. The cavities were sealed with amalgam and euthanasia occurred after 48 h and the jaws were dissected for histologic evaluation. CCL5/RANTES is expressed in all groups, unlike CCR5, that was not expressed. RANKL appears only in inflammatory cells, including control group. Only RANKL could be expressed during initial pulpal inflammation, being able to detect inflammatory cell activity. / Estudos de c?rie demonstraram aspectos inflamat?rios nos tecidos pulpares decorrentes de infec??o estabelecida. Citocinas seriam capazes de ativar c?lulas ligadas ? resposta inflamat?ria e imune no sentido de neutralizar potenciais agentes invasores e permitir o reparo dos tecidos pulpares. Algumas destas, denominadas quimiocinas, poderiam contribuir no estabelecimento de uma imunoterapia capaz de bloquear aquelas citocinas respons?veis pelo processo inflamat?rio. Na inflama??o cr?nica estas pesquisas j? possuem resultados satisfat?rios. Na inflama??o aguda, os estudos ainda est?o inconclusivos. Este estudo teve como objetivo testar as quimiocinas CCL5/RANTES, CCR5 e RANKL na inflama??o pulpar aguda. M?todos: 18 Ratos Wistar foram anestesiados. Foram feitas cavidades at? a exposi??o pulpar nos primeiros molares inferiores. Eles foram divididos em tr?s grupos onde se administrou solu??o salina est?ril, lipopolissacar?deo (LPS) e ?cido lipoteic?ico (LTA) (n= 6 por grupo). Os segundos molares inferiores h?gidos foram utilizados como controle. As cavidades foram seladas com am?lgama e a eutan?sia foi realizada ap?s 48h. As mand?bulas foram dissecadas para exame histol?gico e da imunoexpress?o das quimiocinas em estudo. Obteve-se como resultados: CCL5/RANTES ? expressa em todos os grupos, ao contr?rio do CCR5, que n?o foi expressa. RANKL aparece apenas em c?lulas inflamat?rias. Somente a express?o de RANKL foi capaz de demonstrar atividade celular na inflama??o pulpar inicial.

Made available in DSpace on 2015-04-14T13:30:35Z (GMT). No. of bitstreams: 1 459627.pdf: 7400131 bytes, checksum: 7fad83acbbcc467bba6b608474393763 (MD5) Previous issue date: 2014-02-25 / The dental pulp activates inflammatory and immunopathologic defenses owing to microorganisms. However, pulp tissue is confined by rigid walls and inflammation may perpetuate or extend pathologic alteration due to its own events. Within this context, the enzyme Purine Nucleoside Phosphorylase (PNP) is related to a chain of events that generate activated T cells, thus it becomes an interesting target for pulp inflammation control. Under these circumstances, the present study aimed to characterize the PNP enzyme in rat pulp tissue, by immunohistochemistry, as well as establish a correlation among the inflammatory events with the enzyme, by histologic methods. Eighteen animals were divided into 3 groups: group 1 (n=6) no cavity opening was performed; group 2 (n=6) pulp tissue exposure for 24 hour; group 3 (n=6) pulp tissue exposure for 7 days. Qualitative analysis was applied for histologic observations, which has indicated the same intensity of inflammation for groups 2 and 3. However, in group 3, inflammation was further extended through the pulp. The main inflammatory cells observed were neutrophils, for both experimental periods. No pathologic alterations were shown for the control group. Immunolocalization detected the presence of PNP in endothelial cells of group 3 at the transition period from acute to chronic inflammation. No PNP basal expression was observed for the groups 1 and 2. In conclusion, PNP is activated in rat pulp tissue. Our findings show a novel endodontic target and contribute with ongoing and future endodontic scientific studies that aim drugs development for pulp damage control. / Dentre as fun??es do tecido pulpar, o papel de defesa contra as inj?rias provocadas por microorganismos ocorre com o desenvolvimento dos processos inflamat?rio e imunol?gico. No entanto, a polpa encontra-se confinada por paredes r?gidas e a inflama??o pode perpetuar ou ampliar a altera??o patol?gica em fun??o de seus pr?prios eventos. Dentro deste contexto, a enzima Purina Nucleos?deo Fosforilase (PNF) ? um alvo interessante para o controle de inflama??o pulpar, pois est? relacionada a cascata de eventos que gera c?lulas T ativadas. Sendo assim, o presente estudo objetivou caracterizar a enzima PNF em tecido pulpar de ratos wistar, atrav?s de imunohistoqu?mica, bem como estabelecer correla??o entre a presen?a da enzima PNF e os eventos inflamat?rios observados por m?todo histol?gico. Foram utilizados 18 animais divididos em 3 grupos: grupo 1 [n=6]: sem exposi??o pulpar; grupo 2 [n=6]: com exposi??o pulpar por 24h; grupo 3 [n=6]: com exposi??o pulpar por 7 dias. A an?lise qualitativa aplicada para o m?todo histol?gico indicou maior extens?o inflamat?ria para o grupo 3, sendo que a intensidade de inflama??o permaneceu a mesma para os grupos 2 e 3. O principal tipo celular inflamat?rio encontrado foi o neutr?filo, para ambos per?odos experimentais. O grupo controle n?o apresentou altera??es patol?gicas. A imunolocaliza??o detectou a presen?a da enzima PNF em c?lulas endoteliais no grupo 3. N?o houve express?o basal da enzima nos grupos 1 e 2. Sendo assim, concluiu-se que h? presen?a da enzima PNF no tecido pulpar j? no evento de transi??o do per?odo agudo para o per?odo cr?nico. A partir deste achado, a enzima torna-se alvo interessante de estudos endod?nticos futuros que elucidem seu o papel, objetivando assim, o desenvolvimento de f?rmacos que controlem o dano pulpar.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-17T13:12:44Z No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-18T15:34:49Z (GMT) No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) / Made available in DSpace on 2017-07-18T15:34:49Z (GMT). No. of bitstreams: 1 FernandaGinaniAntunes_TESE.pdf: 2184683 bytes, checksum: 53f3cc6dc1251b2dcdc05b91678ae4d3 (MD5) Previous issue date: 2017-02-23 / O laser de baixa intensidade (LBI) tem apresentado resultados positivos na prolifera??o de diversos tipos celulares in vitro. A primeira parte do trabalho avaliou o efeito do LBI na prolifera??o e viabilidade de c?lulas-tronco da polpa de dentes dec?duos humanos esfoliados (SHED). As c?lulas foram irradiadas ou n?o (controle) com um laser diodo InGaAlP (660 nm, 30 mW, modo de a??o cont?nuo) usando duas diferentes doses (0,5 J/cm2 por 16 segundos e 1,0 J/cm2 por 33 segundos) e os tr?s grupos foram estudados nos intervalos de 0, 24, 48 e 72 h. Foi observado que a dose de 1,0 J/cm2 promoveu um aumento na prolifera??o celular nos intervalos de 48 e 72 h quando comparada ao grupo controle e ? dose de 0,5 J/cm2 e a viabilidade celular n?o foi afetada pela irradia??o ao longo do experimento. Em conjunto, os dados mostraram que os par?metros do LBI utilizados (660 nm, 30 mW, 1,0 J/cm2) promoveram prolifera??o das SHEDs e mantiveram a sua viabilidade. A partir destes resultados favor?veis, a segunda parte do trabalho avaliou o efeito do LBI com os mesmos par?metros na prolifera??o de SHEDs cultivadas sobre arcabou?os nanofibrosos de PLA confeccionados pela t?cnica de eletrofia??o. Este procedimento permite a obten??o de arcabou?os tridimensionais que simulam a matriz extracelular a partir de um biomaterial com propriedades f?sicas favor?veis e baixo custo. Tr?s grupos experimentais (G1 ? n?o irradiado; G2 ? irradiado com 0,5 J/cm2; G3 ? irradiado com 1,0 J/cm2) foram analisados nos intervalos de 24, 48 e 72 h. Os resultados indicaram que o PLA n?o ? citot?xico para as SHEDs e que os grupos submetidos ? laserterapia tiveram maior prolifera??o celular quando comparados com o grupo controle n?o irradiado. Com base nos achados, evidenciou-se que as nanofibras de PLA s?o arcabou?os favor?veis para o cultivo de SHEDs e que a laserterapia estimulou a prolifera??o quando aplicada nas c?lulas cultivadas sobre este arcabou?o. Com base nos dados gerais obtidos, conclui-se que a laserterapia nos par?metros avaliados apresenta efeitos bioestimulat?rios nas SHEDs cultivadas tanto na superf?cie padr?o (pl?stico da placa de cultivo) quanto sobre arcabou?os nanoestruturados de PLA. / The low-level laser therapy (LLLT) has been shown positive results in the in vitro proliferation of several cell types. The first part of the study evaluated the effect of LLLT on the proliferation and viability of stem cells from human exfoliated deciduous teeth (SHED).Cells were irradiated or not (control) with an InGaAlP diode laser (660 nm, 30 mW, continuous action mode) using two different doses (0.5 J/cm2 for 16 seconds and 1.0 J/cm2 for 33 seconds) and the three groups were analyzed at the intervals of 0, 24, 48 and 72 h.It was observed that the dose of 1.0 J/cm2 promoted an increase in cell proliferation at the 48 and 72 h intervals when compared to the control group and the dose of 0.5 J/cm2, and that cell viability was not affected by irradiation throughout the experiment. Taken together, the data showed that the LLLT parameters (660 nm, 30 mW, 1.0 J/cm2) promoted proliferation of SHEDs and maintained their viability. Based on these favorable results, the second part of the study evaluated the effect of LLLT with the same parameters on the proliferation of SHEDs cultured on PLA nanofibrous scaffolds obtained by electrospinning. This procedure allows obtaining three-dimensional scaffolds that mimic the extracellular matrix from a biomaterial with favorable physical properties and low cost.Three experimental groups (G1 - non-irradiated; G2 - irradiated with 0.5 J/cm2; G3 - irradiated with 1.0 J/cm2) were analyzed at 24, 48 and 72 h. The results indicated that PLA is not cytotoxic to SHEDs and that the groups submitted to laser therapy had higher cell growth when compared to the nonirradiated control group. Based on these findings, it was shown that PLA nanofibers are favorable scaffolds for the cultivation of SHEDs and that laser therapy stimulated the proliferation when applied to the cells cultured on this scaffold. Based on the general data obtained, it is concluded that the laser therapy in the evaluated parameters has biostimulatory effects on the proliferation of SHEDs on both the standard surface (plastic of the culture plate) and on nanostructured PLA scaffolds.

Made available in DSpace on 2014-12-17T15:30:59Z (GMT). No. of bitstreams: 1 JaquelineGFD.pdf: 331693 bytes, checksum: f314478d15317d8b20c641a1c60f5ff6 (MD5) Previous issue date: 2006-03-14 / 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 / O sistema neurovascular da polpa e do periodonto ? interligado e, dentre as poss?veis intercomunica??es entre esses dois tecidos, tem-se o canal cavo inter-radicular. Trata-se de um pequeno canal que percorre toda dentina inter-radicular e se exterioriza na regi?o de furca dos dentes multirradiculares. Sua preval?ncia foi estudada na literatura, por diversas metodologias, com resultados divergentes. O objetivo desse trabalho foi estabelecer, in vitro, a preval?ncia do canal cavo inter-radicular, em molares inferiores humanos, atrav?s da t?cnica de infiltra??o de corante e diafaniza??o. Para a pesquisa foram selecionados 140 dentes (100 primeiros e 40 segundos molares inferiores), extra?dos por raz?es diversas, pertencentes ao estoque de dentes da disciplina de Endodontia da Faculdade de Odontologia da Universidade Federal do Rio Grande do Norte. Os dentes anteriormente mantidos em formol foram lavados em ?gua corrente e conservadps em soro fisiol?gico at? o momento de uso. Nesse momento os mesmos tiveram os acessos endod?nticos realizados e toda a superf?cie externa, exceto a furca, impermeabilizada com duas camadas de esmalte de unha. A limpeza do assoalho da c?mara pulpar foi feita com solu??o de hipoclorito de s?dio a 5%, sendo essa solu??o renovada a cada 5 minutos durante 1 hora. Os dentes foram imersos em tinta nanquim e, ap?s secagem do corante, tiveram suas coroas seccionadas na jun??o amelocement?ria. Foram ent?o examinados em um estereomicrosc?pio, onde se observou marcas do corante na furca e ou assoalho pulpar. Feito esse registro, a amostra foi diafanizada e, com os dentes transparentes, p?de-se observar no estereomicrosc?pio, os verdadeiros canais cavo inter-radiculares. Como resultado desse experimento, foi verificada a presen?a desses canais em 13% dos primeiros e 7,5% dos segundos molares avaliados. O estudo demonstrou que a presen?a do canal cavo inter-radicular ? real e a diafaniza??o associada ? infiltra??o de corante um m?todo eficaz para esse tipo de pesquisa