Diagnóstico, planificación del tratamiento y endodoncia de un primer premolar inferior con dos canales mediante tomografía computarizada 3D: reporte de un caso

El tratamiento endodóntico debe considerar que los dientes presentan una morfología del sistema de canales radiculares con alta variabilidad y complejidad. por lo tanto, el conocimiento acabado de la anatomía radicular y la planificación del procedimiento utilizando sistemas imagenológicos previos a la realización del tratamiento endodóntico, como la tomografía computarizada 3D (CBTC), mejoran el pronóstico, aumentando las probabilidades de éxito. el objetivo de este reporte es mostrar la secuencia de una resolución clínica de un primer premolar inferior (diente 4.4) con una anatomía compleja, utilizando el CBTC tanto en el diagnóstico como en la planificación.

The smear layer created by scaling and root planing is physiologically eliminated in a biphasic process

Mechanical instrumentation of the root surface causes the formation of a smear layer, which is a physical barrier that can affect periodontal regeneration. Although different procedures have been proposed to remove the smear layer, there is no information concerning how long the smear layer persists on root surfaces after instrumentation in vivo. This study assessed the presence of the smear layer on root surfaces over a 28-day period after subgingival instrumentation with hand instruments. Fifty human teeth that were referred for extraction because of advanced periodontal disease were scaled and root planed (SRP) by a single experienced operator. Ten teeth were randomly assigned to be extracted 7, 14, 21, and 28 days after SRP. Another 10 teeth were extracted immediately after instrumentation (Day 0, control group). The subgingival area of the instrumented roots was evaluated with scanning electron microscopy. Representative photomicrographs were assessed by a blinded and calibrated examiner according to a scoring system. A rapid and significant (p < 0.05, Z test) initial reduction in the amount of smear layer was observed at 7 days, and a further significant (p < 0.05) decrease was observed 28 days after SRP. Interestingly, even 28 days after SRP, the smear layer was still present on root surfaces. This study showed that the physiological elimination of the smear layer occurred in a biphasic manner: a rapid initial reduction was observed 7 days after instrumentation, which was followed by a slow process leading to a significant decrease 28 days after instrumentation.

Ultrastructural evaluation of the hybrid layer after cementation of fiber posts using adhesive systems with different curing modes

This in vitro study evaluated the adhesive interface of intraradicular fiber glass posts and root dentin using scanning electron microscopy (SEM). Forty-eight single-rooted premolars were randomly divided into 6 groups consisting of chemical, dual, or light cured adhesive systems combined with either chemical or dual cure resin cements. Scanning electron microscopic analysis showed the best results for continuity, density and morphology of the hybrid layer and resin tags for the combination of a self-cure adhesive with self-cure cement resin, followed by a dual-cure adhesive with self-cure cement resin, and finally a light-cure adhesive with self-cure cement. For the dual-cure resin cement, the same relation may be observed. The apical third was the most critical region for evaluated the criteria for all combinations of materials (Kruskal-Wallis and Friedman tests; p<0.001). Generally, the simplification of steps in the adhesive system and the polymerization reaction of resin adhesives and cements produced a direct effect on the quality of the adhesive post/dentin substrate interface.

Este estudo in vitro avaliou as interfaces adesivas de pinos intra-radiculares de fibra de vidro e a dentina radicular utilizando microscópio eletrônico de varredura (MEV). Quarenta e oito pré-molares unirradiculares foram divididos ao acaso em seis grupos, compostos por sistemas adesivos de cura química, dual ou fotopolimerizável, associado com cimentos resinosos de polimerização química ou dual. As análises microscópicas mostraram a maior continuidade, densidade e morfologia da camada híbrida e prolongamentos resinosos para a associação entre adesivos e cimentos auto-polimerizáveis seguido pelo grupo do adesivo de dupla polimerização e cimento de resina auto-polimerizável, e finalmente pelo adesivo fotopolimerizável e cimento de resina auto-polimerizável . Para os cimentos resinosos de dupla polimerização a mesma relação pode ser observada. O terço apical mostrou ser o substrato mais crítico em relação aos critérios avaliados para todas as associações entre os materiais usados(testes de Kruskal-Wallis e Friedman p<0,001). De maneira geral, a simplificação dos passos do sistema adesivo e a reação de polimerização dos adesivos e cimentos resinosos produzem efeitos diretos na qualidade da interface adesivo pino/dentina.

A comparison of root surface instrumentation using manual, ultrasonic and rotary instruments: An in vitro study using scanning electron microscopy.

Background: The commonly accepted idea concerning root planing is that excessive removal of cementum is not necessary for removal of endotoxins. The ideal instrument should enable the removal of all extraneous substances from the root surfaces, without causing any iatrogenic effects. Aim: To compare the remaining calculus, loss of tooth substance, and roughness of root surface after root planing with Gracey curette, ultrasonic instrument (Slimline® insert FSI-SLI-10S), and DesmoClean® rotary bur. Materials and Methods: The efficiency of calculus removal, the amount of lost tooth substance, and root surface roughness resulting from the use of hand curette, ultrasonic instrument, and rotary bur on 36 extracted mandibular incisors were examined by SEM. We used three indices to measure the changes: Remaining calculus index (RCI), Loss of tooth substance index (LTSI), and Roughness loss of tooth substance index (RLTSI). Twelve samples were treated with each instrument. The time required for instrumentation was also noted. Statistical Analysis: Kruskal-Wallis ANOVA was used for multiple group comparisons and the Mann-Whitney test for group-wise comparisons. Analysis was carried out with SPSS® software (version 13). Results and Conclusion: The RCI and LTSI showed nonsignificant differences between the three groups. RLTSI showed a significant difference between Slimline™ and hand curette as well as Slimline™ and Desmo-Clean™. Slimline™ showed the least mean scores for RCI, LTSI, and RLTSI. Thus, even though the difference was not statistically significant, Slimline™ insert was shown to be better than the other methods as assessed by the indices scores and the instrumentation time.

Comparison among four commonly used demineralizing agents for root conditioning: a scanning electron microscopy

Dental roots that have been exposed to the oral cavity and periodontal pocket environment present superficial changes, which can prevent connective tissue reattachment. Demineralizing agents have been used as an adjunct to the periodontal treatment aiming at restoring the biocompatibility of roots. OBJECTIVE: This study compared four commonly used demineralizing agents for their capacity of removing smear layer and opening dentin tubules. METHODS: Fifty fragments of human dental roots previously exposed to periodontal disease were scaled and randomly divided into the following groups of treatment: 1) CA: demineralization with citric acid for 3 min; 2) TC-HCl: demineralization with tetracycline-HCl for 3 min; 3) EDTA: demineralization with EDTA for 3 min; 4) PA: demineralization with 37 percent phosphoric acid for 3 min; 5) Control: rubbing of saline solution for 3 min. Scanning electron microscopy was used to check for the presence of residual smear layer and for measuring the number and area of exposed dentin tubules. RESULTS: Smear layer was present in 100 percent of the specimens from the groups PA and control; in 80 percent from EDTA group; in 33.3 percent from TC-HCl group and 0 percent from CA group. The mean numbers of exposed dentin tubules in a standardized area were: TC-HCl=43.8±25.2; CA=39.3±37; PA=12.1±16.3; EDTA=4.4±7.5 and Control=2.3±5.7. The comparison showed significant differences between the following pairs of groups: TC-HCl and Control; TC-HCl and EDTA; CA and Control; and CA and EDTA. The mean percentages of area occupied by exposed dentin tubules were: CA=0.12±0.17 percent; TC-HCl=0.08±0.06 percent; PA=0.03±0.05 percent; EDTA=0.01±0.01 percent and Control=0±0 percent. The CA group differed significantly from the others except for the TC-HCl group. CONCLUSION: There was a decreasing ability for smear layer removal and dentin tubule widening as follows: AC>TC-HCl>PA>EDTA. This information can be of value as an extra parameter for choosing one of them for root conditioning.

Ultramorphology of the root surface subsequent to hand-ultrasonic simultaneous instrumentation during non-surgical periodontal treatments: an in vitro study

OBJECTIVE: The purpose of this study was to investigate the ultramorphology of the root surfaces induced by mechanical instrumentation performed using conventional curettes or piezoelectric scalers when used single-handedly or with a combined technique. MATERIAL AND METHODS: Thirty single-rooted teeth were selected and divided into 3 groups: Group A, instrumentation with curettes; Group B instrumentation with titanium nitride coated periodontal tip mounted in a piezoelectric handpiece; Group C, combined technique with curette/ultrasonic piezoelectric instrumentation. The specimens were processed and analyzed using confocal and scanning electron microscopy. Differences between the different groups of instrumentation were determined using Pearson's χ2 with significance predetermined at α=0.001. RESULTS: Periodontal scaling and root planing performed with curettes, ultrasonic or combined instrumentation induced several morphological changes on the root surface. The curettes produced a compact and thick multilayered smear layer, while the morphology of the root surfaces after ultrasonic scaler treatment appeared irregular with few grooves and a thin smear layer. The combination of curette/ultrasonic instrumentation showed exposed root dentin tubules with a surface morphology characterized by the presence of very few grooves and slender remnants of smear layer which only partially covered the root dentin. In some cases, it was also possible to observe areas with exposed collagen fibrils. CONCLUSIONS: The curette-ultrasonic simultaneous instrumentation may combine the beneficial effects of each instrument in a single technique creating a root surface relatively free from the physical barrier of smear layer and dentin tubules orifices partial occlusion.

Effect of instrumentation using curettes, piezoelectric ultrasonic scaler and Er,Cr:YSGG laser on the morphology and adhesion of blood components on root surfaces: a SEM study

This study used scanning electron microscopy (SEM) to evaluate the morphology and adhesion of blood components on root surfaces instrumented by curettes, piezoelectric ultrasonic scaler and Er,Cr:YSGG laser. One hundred samples from 25 teeth were divided into 5 groups: 1) Curettes; 2) Piezoelectric ultrasonic scaler; 3) Curettes plus piezoelectric ultrasonic scaler; 4) Er,Cr:YSGG laser; 5) Curettes plus Er,Cr:YSGG laser. Ten samples from each group were used for analysis of root morphology and the other 10 were used for analysis of adhesion of blood components on root surface. The results were analyzed statistically by the Kruskall-Wallis and Mann-Whitney tests with a significance level of 5 percent. The group treated with curettes showed smoother surfaces when compared to the groups were instrumented with piezoelectric ultrasonic scaler and the Er,Cr:YSGG laser. The surfaces instrumented with piezoelectric ultrasonic scaler and Er,Cr:YSGG laser, alone or in combination with hand scaling and root planing, did not differ significantly (p>0.05) among themselves. No statistically significant differences (p>0.05) among groups were found as to the adhesion of blood components on root surface. Ultrasonic instrumentation and Er,Cr:YSGG irradiation produced rougher root surfaces than the use of curettes, but there were no differences among treatments with respect to the adhesion of blood components.

Esse estudo utilizou microscopia eletrônica de varredura (MEV) para avaliar a morfologia e a adesão de elementos sanguíneos em superfícies radiculares instrumentadas com curetas, ultrassom piezoelétrico e laser de Er,Cr:YSGG. Foram utilizadas no presente estudo 100 amostras provenientes de 25 dentes que foram divididas em 5 grupos: 1) Raspagem manual com curetas; 2) Raspagem com ultrassom; 3) Associação instrumento manual e ultrassom; 4)Irradiação do laser de Er,Cr:YSGG;5)Associação raspagem manual com irradiação com laser de Er,Cr:YSGG. Dez amostras de cada grupo foram utilizadas para análise da morfologia e as outras 10 foram utilizadas para a análise de adesão de elementos sanguíneos. As eletromicrografias foram analisadas através dos escores de adesão de elementos sanguíneos e pelo índice de morfologia radicular e os resultados foram analisados estatisticamente através dos testes de Kruskall-Wallis e de Mann-Whitney com nível de significância de 5 por cento. O grupo que foi tratado com instrumentos manuais apresentou superfície mais lisa em relação aos grupos que foram instrumentados com ultrassom e com o laser de Er,Cr:YSGG. As superfícies instrumentadas com ultrassom e com o laser de Er,Cr:YSGG de forma isolada ou associada a raspagem manual não apresentaram diferenças estatísticas entre si (p>0,05). Não houve diferenças estatísticas entre os grupos em relação a adesão de elementos sanguíneos(p>0,05). A instrumentação ultrassônica e a irradiação com o laser de Er,Cr:YSGG produziram superfícies radiculares mais rugosas em relação a raspagem com curetas, porém não houve diferenças entre os tratamentos com relação à adesão de elementos sanguíneos.

Influence of dental exposure to oral environment on smear layer removal and collagen exhibition after using different conditioning agents

Although in vitro studies have shown encouraging results for root surface conditioning with demineralizing agents, in vivo studies have failed to show its benefits in periodontal healing. This can be attributed to several factors, among which, the hypermineralization of dental surface. Therefore, this in vitro study compared, using scanning electron microscopy (SEM), the effect of root surface conditioning with different conditioners (1% and 25% citric acid, 24% EDTA and 50 mg/mL tetracycline hydrochloride) in impacted teeth and in teeth that had their roots exposed to the oral environment. One trained examiner assessed the SEM micrographs using a root surface modification index. There was a tendency of more root surface modification in the group of impacted teeth, suggesting that the degree of root mineralization influences its chemical demineralization.

Apesar de estudos in vitro terem demonstrado resultados favoráveis ao condicionamento da superfície radicular com agentes desmineralizantes, estudos in vivo não mostraram seus benefícios na cicatrização periodontal. Isto pode ser atribuído a vários fatores, entre os quais, a hipermineralização da superfície dental. Portanto, este estudo in vitro comparou, usando microscopia eletrônica de varredura, o efeito do condicionamento da superfície radicular com diferentes condicionadores (1% e 25% de ácido cítrico, EDTA 24% e 50 mg/mL de cloridrato de tetraciclina) em dentes impactados e dentes que tinham suas raízes expostas ao meio bucal. Um examinador treinado avaliou as microscopias eletrônicas de varredura utilizando um índice de modificação da superfície radicular. Houve uma tendência de maior modificação da superfície radicular no grupo de dentes impactados, sugerindo que o grau de mineralização da raiz influencia a sua desmineralização química.

A scanning electron microscopic study of the patterns of external root resorption under different conditions

OBJECTIVE: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. MATERIAL AND METHODS: A total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging from 20x to 1000x. Group I: 10 primary molars exfoliated due to physiologic root resorption; Group II: 10 permanent teeth with periapical granulomas showing signs of resorption; Group III:10 permanent teeth therapeutically extracted during the course of orthodontic therapy with evidence of resorption, and Group IV: 10 permanent teeth associated with odontogenic tumors that showed evidence of resorption. RESULTS: In Group I, the primary teeth undergoing resorption showed smooth extensive and predominantly regular areas reflecting the slow ongoing physiologic process. In Group II, the teeth with periapical granulomas showed the resorption was localized to apex with a funnel shaped appearance in most cases. Teeth in Group III, which had been subjected to a short period of light orthodontic force, showed the presence of numerous resorption craters with adjoining areas of cemental repair in some cases. Teeth associated with odontogenic tumors in Group IV showed many variations in the patterns of resorption with extensive loss of root length and a sharp cut appearance of the root in most cases. CONCLUSION: Differences were observed in the patterns of external root resorption among the studied groups of primary and permanent teeth under physiologic and pathological conditions.

Comparison of resin push-out strength to root dentin of bovine- and human-teeth.

Aim : To compare the push-out strength of bovine- and human-root dentin and, thus, evaluate the suitability of bovine-root dentin to substitute human-root dentin for bond strength testing. Materials and Methods : Ten single-rooted human-teeth and ten bovine incisors were prepared using a #3 bur of a fiber post system (12 mm long). The posts were duplicated with resin cement (Duolink). The root canals were treated with All Bond 2 adhesive system and the resin posts were cemented using Duolink. The specimens were cut perpendicular to their long axis, yielding disc-specimens with 1.5 mm thickness, which were submitted to a push-out test (1 mm/min). Ten bond strength values per group (n = 10) were used for statistical analysis (Student t test, a =.05). Results : Statistically significant differences were found for the bond strength values between bovine- (4.1 ± 1.3 MPa) and human-root dentin (8.6 ± 5.7 MPa) (P =.0001). Conclusion : The push-out strengths of bovine- and human-root dentin were statistically different.

Rugosidade de dentona radicular após tratamento com cureta manual, utrassom, laser de Er: TAG e jato de bicarbonato / Dentine root surface roughness following treatment with manual curattes, ultrasonic system. Er: YAG laser and air-powder abrasive system

OBJETIVOS: O objetivo deste estudo in vitro foi avaliar os efeitos do laser de Er: YAG, de dois sistemas ultrassônicos e da cureta manual, associados ou não à aplicação do jato de bicarbonato, na rugosidade superficial da dentina radicular. MATERIAIS E MÉTODOS: Cinquenta corpos de prova, provenientes de raízes bovinas, obtiveram o cemento removido por meio de lixas para exposição da dentina radicular. Em seguida, foram divididos aleatoriamente em cinco grupos de tratamento: Grupo 1: cureta de Gracey; Grupo 2: ultrassom Jet Sonic®; Grupo 3: ultrassom Cavitron®; Grupo 4: laser de Er: YAG; Grupo 5: jato de bicarbonato. Subsequentemente, os Grupos 1,2,3 e 4 foram submetidos à aplicação do jato de bicarbonato. A rugosidade superficial foi analisada por meio de um rugosímetro digital antes e após os tratamentos. RESULTADOS: Todos os instrumentos produziram um aumento da rugosidade superficial (p

OBJECTIVES: The aim of this in vitro study was to evaluate the effects of the Er: YAG laser, two ultrasonic systems and manual curette, associated or not with the application of air-powder abrasive system on the roughness of dentine root surface. MATERIALS AND METHODS: The cement from fifty samples of bovine roots were removed by means of abrasive sandpaper to expose the dentine surface. Afterward, the samples were randomly assigned to one of the following treatment groups: Group 1: Gracey curette; Group 2: Jet Sonic® ultrasonic system; Group 3: Cavitron® ultrasonic system; Group 4: Er: YAG laser; Group 5: air-powder abrasive system. Subsequently, the samples from groups 1,2,3 and 4 were treated with air-powder abrasive system. The superficial roughness (Ra) was examined using a profilometer before and after treatments. RESULTS: All instruments increased the roughness of the dentine root surface after treatments (p

A scanning electron microscopic study of hypercementosis

The purpose of this study was to evaluate morphological characteristics of teeth with hypercementosis that are relevant to endodontic practice. Twenty-eight extracted teeth with hypercementosis had their root apexes analyzed by scanning electron microscopy (SEM). The teeth were divided according to tooth groups and type of hypercementosis. The following aspects were examined under SEM: the contour and regularity of the root surface; presence of resorption; presence and number of apical foramina, and the diameter of the main foramen. The progression of club shape hypercementosis was directly associated with the presence of foramina and apical foramen obstruction. Cases of focal hypercementosis presented foramina on the surface, even when sidelong located in the root. Circular cementum hyperplasia form was present in 2 out of 3 residual roots, which was the highest proportion among the tooth types. The detection of a large number of foramina in the apical third of teeth with hypercementosis or even the possible existence of apical foramen obliteration contributes to understand the difficulties faced during endodontic treatment of these cases.

Influencia del surco palato-gingival sobre la anatomía radicular y canalicular / The influence of palato-gingival groove on radicular and canal anatomy

El surco palato-gingival es una anomalía de desarrollo que produce cambios morfológicos y estructurales en la cara palatina de la corona y raíz de incisivos permanentes superiores. La magnitud de la lesión es muy variada y en ciertos casos provoca importantes deformaciones en la raíz y cavidad pulpar, con graves complicaciones pulpares y periodontales que pueden ocasionar la pérdida del diente. Ante esta situación anatómica un tanto compleja, y no siempre de fácil diagnóstico, nos propusimos como objetivo estudiar con una visión endodóntica, la influencia que esta anomalía tiene sobre la macroy microestructura radicular y, en consecuencia, sobre la cavidad pulpar. En cortes transversales de raíces que presentaban esta patología, se observó que los defectos podían ser muy variados y que en los casos donde la lesión era muy acentuada, se producían importantes cambios, que evidenciaban un intento de bifurcación tanto enl a raíz como en el conducto.

The influence of the surgical operating microscope in locating the mesiolingual canal orifice: a laboratory analysis

O objetivo deste estudo foi avaliar a influência do uso do microscópio cirúrgico na localização do canal mesiopalatino (MP) em primeiros molares superiores humanos permanentes extraídos. Cento e oito primeiros molares superiores permanentes foram selecionados aleatoriamente e montados em um manequim dental. Uma cavidade de acesso convencional foi realizada e uma tentativa de se localizar o canal mesiopalatino foi feita, utilizando-se somente uma sonda exploradora afiada, um odontoscópio e uma lima tipo K tamanho 10. Quando não localizado o referido canal, os dentes foram então avaliados com auxílio de um microscópio cirúrgico (MC). As raízes mésio-vestibulares de todos os dentes nos quais o canal MP não foi localizado foram então seccionadas transversalmente e exploradas com auxílio do MC, com um aumento de 25 X. Os canais MP foram detectados em 58 dentes em que se usaram somente uma sonda exploradora afiada, um odontoscópio e uma lima tipo K tamanho 10. Nos 50 dentes restantes, 37 canais MP foram localizados com o auxílio do MC e 3 canais MP foram localizados após a secção das raízes. Em 10 dentes os canais MP não foram localizados. Os resultados deste estudo mostraram uma alta incidência do canal MP na raiz mésio-vestibular do primeiro molar superior permanente (90.7%) e demonstraram que o uso adjunto do MC aumentou a capacidade do operador em localizar o canal MP.

Scanning electron microscopic analysis of the effect of CarisolvTM gel on periodontally compromised human root surfaces

A utilização do CarisolvTM tem sido proposta como um método auxiliar à raspagem e ao alisamento radicular (RAR), a fim de facilitar a descontaminação da superfície da raiz. O objetivo deste estudo foi avaliar, através da microscopia eletrônica de varredura (MEV), as características das superfícies radiculares, após a aplicação do CarisolvTM em associação à RAR. Sessenta dentes humanos extraídos devido à doença periodontal foram divididos em 6 grupos: 1) RAR ; 2) CarisolvTM (aplicação passiva) + RAR; 3) CarisolvTM (aplicação ativa) + RAR; 4) CarisolvTM (aplicações múltiplas) + RAR; 5) RAR + EDTA a 24%; 6) CarisolvTM + RAR + EDTA a 24%. CarisolvTM foi aplicado às superfícies radiculares por 30 s, seguido de raspagem e alisamento radicular, que consistiu de 50 movimentos com curetas de Gracey no sentido corono-apical, co o instrumento paralelo ao longo eixo do dente. A única exceção foi o grupo 4, no qual as raízes foram instrumentadas até obter uma superfície lisa, dura e com aspecto vítreo. Os espécimens tratados foram preparados e examinados em MEV. Os resultados demonstraram que a associação do CarisolvTM aos procedimentos periodontais mecânicos proporcionou modificações significativas na superfície radicular quando comparada à raspagem e ao alisamento radicular, apenas quando o CarisolvTM foi aplicado de forma ativa. A aplicação do CarisolvTM uma única vez, apresentou um efeito limitado na capacidade de remoção de smear layer, sendo que aplicações sucessivas apresentaram resultados comparáveis àqueles obtidos após a aplicação do EDTA.

Blood cell attachment to root surfaces treated with EDTA gel

A raspagem gera "smear layer", a qual contém microrganismos e toxinas que podem interferir no reparo periodontal. Por esse motivo, diferentes substâncias têm sido empregadas para remover esta camada e expor fibras colágenas da superfície dental. A adesão de elementos sangüíneos a superfícies radiculares desmineralizadas e a estabilizacão do colágeno pelas fibras colágenas são de extrema importância no sucesso da cirurgia periodontal. O objetivo deste estudo foi avaliar os diferentes padrões de adsorcão e adesão de elementos sangüíneos a superfícies radiculares apenas irrigadas com água destilada e após aplicacão de um gel de EDTA manipulado ou um industrializado. Trinta amostras foram raspadas, eqüitativamente divididas em 3 grupos e tratadas com água destilada (controle), um gel de EDTA manipulado ou um industrializado. Imediatamente foram expostas a sangue fresco e preparadas para microscopia eletrônica de varredura. As superfícies dentinárias apenas raspadas apresentaram os melhores resultados, com moderada quantidade de células sangüíneas entremeadas em uma fina rede de fibrina. No grupo de EDTA manipulado, a rede de fibrina foi pouco visível com escassas células. Os piores resultados foram observados com o EDTA industrializado, caracterizados pela ausência de elementos sangüíneos. Estatisticamente houve diferenca apenas entre os grupos controle e EDTA industrializado. As superfícies apenas irrigadas apresentaram rede de fibrina mais bem organizada com células entremeadas.

Evaluation of efficacy of Sofscale. A clinical and SEM study.

Efficacy of Sofscale in the case of removal of calculus from the root surface as claimed by manufacturers was evaluated in the present study. 32 patients suffering from chronic periodontitis, having calculus deposits in the lower incisors were selected for the study. A double blind study was conducted to evaluate the ease with which calculus could be removed. In the second part of study, a SEM study of the root surface subjected to root planing alone and root planing after application of Sofscale was done to see whether any remnants of calculus was left behind. In the double blind study conducted on 32 patients, it was found in 21 patients, calculus could be removed with greater ease and less time in experimental area compared to the control. 17 patients were able to correctly identify the product side as easier to Sofscale. Patients did not complain of increased sensitivity of teeth or discomfort following application of Sofscale. Under SEM the root surface after root planing showed the presence of smear layer whereas after Sofscale application root surface appeared devoid of smear layer. No other significant difference were noticed between the root surfaces.

Avaliaçäo da ocorrência de canais acessórios na furca e no terço cervical radicular de molares humanos: estudo dos forames em microscópio eletrônico de varredura / Evaluation of the occurrence of accessory canals in the furcae and in the cervical third of human molars: a foramina study under scanning electron microscope

Foram examinados no presente trabalho forames acessórios nas furcas de 62 molares permanentes superiores e inferiores recém-extraídos, na superfície cervical radicular externa e no terço cervical do canal radicular, empregando a microscopia eletrônica de varredura. Constataram-se, no grupo I, 65,99 por cento de forames na furca e 87,77 por cento de forames na superfície radicular externa (Grupo II). No interior dos canais radiculares (Grupo III), na sua porçäo cervical, foram encontrados 66,66 por cento. Conclui-se que a freqüência de canais acessórios comunicando o periodonto cervical com a polpa do dente é de 2/3 em molares