94 research outputs found
Lysanda paste: a new option for root-end filling
This study aimed to compare the apical sealing of root-end fillings performed with Lysanda (zinc oxide-eugenol paste) with radiopacifiers (iodoform or zinc oxide) and calcium hydroxide. Root-end cavities were prepared and filled with different materials, as follows: Group I - Lysanda paste with iodoform; Group II - Lysanda paste with iodoform and calcium hydroxide; Group III - Lysanda paste with iodoform and zinc oxide; Group IV - Lysanda paste with zinc oxide; Group V - mineral trioxide aggregate (MTA). After filling, the teeth were immersed in 2% methylene blue for analysis of marginal leakage. It was observed that marginal leakage occurred in all groups. Lysanda paste with iodoform showed the lowest leakage, with no statistically significant difference compared to the other groups. All materials can be considered as good options for root-end filling
Análise comparativa entre instrumentação rotatória (GT), manual e associação de ambas no preparo de canais achatados
Root canal preparation has been considered one of the most important steps in root canal therapy, thus many techniques and instruments have been developed. The aim of this study was to evaluate the cleaning of the root canal through three different instrumentation techniques. Thirty mandibular incisors were selected and submitted to lingual access cavities. Afterwards, the canals were filled with India ink dye previously stored in carpules, which was inserted into the root canal by means of anesthetic syringe and anesthetic needles. After 48 hours, during which the dye was allowed to dry inside the root canal, the teeth were divided in three groups: G1- GT rotatory instrumentation; G2- manual instrumentation; G3- association of both. After instrumentation, the teeth were longitudinally sectioned. The cleaning process accomplished through the different instrumentation techniques was evidenced by dye removal at the cervical, middle and apical thirds of the root canal. The results of this study showed that were not statistically significant differences between these three instrumentation techniques for all three thirds of the root canal.A instrumentação do canal radicular tem sido considerada uma das fases mais importantes do tratamento endodôntico, portanto muitas técnicas e instrumentos têm sido desenvolvidos para esse fim. O propósito desse estudo foi avaliar a limpeza de canais radiculares instrumentados com três diferentes técnicas. Foram selecionados trinta incisivos inferiores, onde a abertura coronária foi realizada. Posteriormente, os canais foram preenchidos com tinta nanquim (corante), previamente acondicionada em tubetes anestésicos, sendo a mesma levada ao interior do canal radicular com auxílio de uma seringa carpule e uma agulha para anestesia. Após 48 horas, tempo esperado para que o corante secasse no canal, os dentes foram divididos em três grupos: G1 - instrumentação rotatória com GT; G2 - instrumentação manual e G3 - associação de ambas (mista). Após a instrumentação, os dentes foram seccionados longitudinalmente e realizada a avaliação da limpeza dos canais, através da remoção de corante nos terços cervical, médio e apical. Os resultados demonstraram que não houve diferença estatisticamente significante na limpeza do canal entre as três técnicas de instrumentação estudadas, nos três terços avaliados
Sealing ability, marginal adaptation and their correlation using three root-end filling materials as apical plugs
OBJECTIVE: This study used dye leakage assay and scanning electron microscopy to evaluate, respectively, the sealing ability and marginal adaptation of three root-end filling materials used as apical plugs, as well as the possible correlation between these properties. MATERIAL AND METHODS: Ninety-eight single-rooted human teeth were prepared to simulate an open apex. The teeth were allocated to three experimental groups (n = 30), which received a 5-mm thick apical plug of (1) gray MTA AngelusTM, (2) CPM TM and (3) MBPc, and two controls groups (n = 4). After immersion in 0.2% Rhodamine B solution for 48 h, the teeth were sectioned longitudinally and analyzed by Image Tool 3.0 software. The marginal adaptation between apical plugs and the root canal walls were analyzed by SEM. RESULTS: MBPc had significantly less (p<0.05) apical leakage than the other materials. Regarding marginal adaptation, CPM TM showed the best numerical results, though without statistical significance from the other materials (p<0.05). There was no correlation between the two properties. CONCLUSIONS: When used as apical plugs, the tested root-end filling materials had similar marginal adaptation to the dentin walls, but MBPc had the best sealing ability, as demonstrated by the least apical leakage from all tested materials
Influência do EDTA, do laser de Nd: YAG e da associação de ambos na obturação de canais laterais artificiais
Este estudo teve como objetivo avaliar a ação do EDTA, do laser de Nd:YAG e a associação de ambos na obturação dos canais laterais artificiais. Foram utilizados 45 dentes pré-molares inferiores humanos, nos quais foram confeccionados três canais laterais com o auxílio de um alargador com diâmetro compatível de uma lima do tipo K número 15. Os dentes foram instrumentados pela técnica regressiva utilizando brocas de Gates Glidden nos terços cervical e médio e limas manuais no terço apical e irrigação com hipoclorito de sódio a 1 %. Os dentes foram divididos em três grupos: Grupo I EDTA por 5 minutos, Grupo II aplicação de laser de Nd:YAG com 15 Hz, 100mJ e 1,5 Watts e Grupo III a associação de ambos. As raízes foram obturadas pela técnica Híbrida de Tagger, radiografadas e as radiografias escaneadas. Para o preenchimento dos canais laterais foram dados escores. A análise estatística mostrou não haver diferença significante entre os grupos analisados globalmente e nem quando analisados por terços.This study aimed at evaluating the influence of EDTA, Nd:YAG laser and the combination of both for filling of artificial lateral root canals. Forty-five human mandibular premolars were employed, on which three artificial lateral root canals were prepared by means of a reamer with a similar diameter to a K file #15. The teeth were instrumented through the stepback technique employing Gates Glidden burs at the middle and cervical thirds and manual files at the apical portion, and irrigation with 1% sodium hypochloride. The teeth were divided in three groups: Group 1 -EDTA for 5 minutes; Group 2 -application of Nd:YAG laser at 15 Hz, 100 mJ and 1.5 Watts; and Group 3 - association of both. Roots were filled through the Tagger's hybrid technique, radiographed and the radiographs were digitized. Scores were assigned to the filling of the lateral root canals. Statistical analysis revealed no significant differences between the entire groups and also on the analysis of each third
Physicochemical properties of calcium silicate-based formulations MTA Repair HP and MTA Vitalcem
Objective: This study aimed to analyze the following physicochemical properties: radiopacity, final setting time, calcium release, pH change, solubility, water sorption, porosity, surface morphology, and apatite-forming ability of two calcium silicate-based materials. Material and methods: We tested MTA Repair HP and MTA Vitalcem in comparison with conventional MTA, analyzing radiopacity and final setting time. Water absorption, interconnected pores and apparent porosity were measured after 24-h immersion in deionized water at 37°C. Calcium and pH were tested up to 28 d in deionized water. We analyzed data using two-way ANOVA with Student-Newman-Keuls tests (p<0.05). We performed morphological and chemical analyses of the material surfaces using ESEM/EDX after 28 d in HBSS. Results: MTA Repair HP showed similar radiopacity to that of conventional MTA. All materials showed a marked alkalinizing activity within 3 h, which continued for 28 d. MTA Repair HP showed the highest calcium release at 28 d (p<0.05). MTA Vitalcem showed statistically higher water sorption and solubility values (p<0.05). All materials showed the ability to nucleate calcium phosphate on their surface after 28 d in HBSS. Conclusions: MTA Repair HP and MTA Vitalcem had extended alkalinizing activity and calcium release that favored calcium phosphate nucleation. The presence of the plasticizer in MTA HP might increase its solubility and porosity. The radiopacifier calcium tungstate can be used to replace bismuth oxide
Final irrigation protocols can be used to promote stable long-term bond strength of AH Plus to dentin
Irrigation solutions might affect dentin surface characteristics and, consequently, endodontic sealers adhesion. Objective: This study analyzed the effect of different final irrigation protocols on push-out bond strength (BS) of AH Plus to dentin seven days and 20 months after obturation. Scanning electron micrographs were obtained from the dentin surface of one sample/group after final irrigation. Methodology: Canals of bovine incisors were instrumented and received final irrigation with (n=21): G1 – 2.5% sodium hypochlorite (NaOCl) + distilled water; G2 – 2.5% NaOCl + 17% EDTA; G3 – 2.5% NaOCl + 17% EDTA + 2.5% NaOCl; G4 – 2.5% NaOCl + 17% EDTA + 2% chlorhexidine (CHX); G5 – mixture 5% NaOCl + 18% etidronate (HEDP); and G6 – mixture 5% NaOCl + 10% tetrasodium EDTA (Na4EDTA). After irrigation, one root/group was split and images were obtained by scanning electron microscopy (SEM). The other 20 roots/group were filled with only AH Plus sealer. Three slices/root were used for push-out assessment seven days and 20 months after obturation. One-way analysis of variance and Tukey (α<0.05) were used to compare the results among experimental groups, and unpaired t-test (α<0.05) was used to compare the results of the same group over time. Results: The photomicrographs showed that, excepting G1, all groups completely removed the smear layer from the samples. In G2 and G4, the opening of the dentin tubules enlarged. In G3, erosion was observed in the peritubular and intertubular dentin. Values of the BS in the seven days were G2=G3=G4=G5>G6=G1 and in the 20 months were G3=G5>G6=G4>G1=G2. G3, G5, and G6 presented values of BS in 20 months similar to the values of seven days (P>0.05). Conclusions: The final irrigation protocols tested produced dentin surfaces with different characteristics. Only G3 and G5 presented high BS values that were stable over time
Antibacterial activity of propolis-based toothpastes for endodontic treatment
This study evaluated the antibacterial activity of propolis-based toothpastes used as intracanal medication in endodontic treatment. The propolis-based toothpastes were prepared using an extract established in previous studies (identified as A70D and D70D). Calcium hydroxide paste was used as a control. The bacteria employed were Streptococcus mutans (ATCC 25175), Staphylococcus aureus (ATCC 6538), Staphylococcus aureus (ATCC 25923), Kocuria rhizophila (ATCC 9341), Escherichia coli (ATCC 10538), Pseudomonas aeruginosa (ATCC 27853), Enterococcus hirae (ATCC 10541), Streptococcus mutans (ATCC 25175). Five field strains isolated from saliva were used: Staphylococcus spp. (23.1 - coagulase positive), Staphylococcus spp. (23.5 - coagulase negative), Staphylococcus spp. (26.1 - coagulase positive), Staphylococcus spp. (26.5 - coagulase negative) and Staphylococcus epidermidis (6epi). The diffusion-well method on double-layer agar was used in a culture medium of Tryptic Soy Agar. The plates were kept at room temperature for two hours to allow the diffusion of pastes in the culture medium, and then incubated at 35º C for twenty-four hours in aerobiosis and in microaerophilia (S. mutans). After this period, the total diameter of the inhibition halo was measured. The results were analyzed by ANOVA analysis of variance, followed by the Tukey test at p<0.05. The propolis-based toothpastes presented antibacterial activity against 83.3% of the analyzed bacteria. For 66.7% of these bacteria, the propolis-based toothpastes exhibited greater antibacterial activity than calcium hydroxide. The present results allow us to conclude that the experimental pastes A70D and D70D showed good activity against aerobic bacteria, proving more effective than calcium hydroxide.O objetivo deste estudo foi avaliar a atividade antibacteriana de formas farmacêuticas a base de própolis para uso no tratamento endodôntico como medicação intracanal. As formulações de própolis, em forma de pastas, foram preparadas a partir de um extrato pré-estabelecido em estudos anteriores e identificadas como A70D e D70D. Como controle, foi utilizado pasta de hidróxido de cálcio. As bactérias utilizadas foram: Streptococcus mutans (ATCC 25175), Staphylococcus aureus (ATCC 6538), Staphylococcus aureus (ATCC 25923), Kocuria rhizophila (ATCC 9341), Escherichia coli (ATCC 10538), Pseudomonas aeruginosa (ATCC 27853), Enterococcus hirae (ATCC 10541), Streptococcus mutans (ATCC 25175) e 5 cepas de campo isoladas da saliva: Staphylococcus spp. (23.1 - coagulase positiva), Staphylococcus spp. (23.5 - coagulase negativa), Staphylococcus spp. (26.1 - coagulase positiva), Staphylococcus spp. (26.5 - coagulase negativa) e Staphylococcus epidermidis (6epi). Foi utilizado o método poço difusão em camada dupla de ágar, em meio de cultura Tryptic Soy Agar. As placas foram mantidas à temperatura ambiente por 2 h para permitir a difusão das pastas no meio de cultura, e então incubadas a 35 ºC por 24 h em aerobiose e em microaerofilia (S. mutans). Após este período, foi medido o diâmetro total do halo de inibição. Os resultados foram submetidos ao teste de análise de variância ANOVA seguido do teste de Tukey com p<0,05. As pastas a base de própolis apresentaram atividade antibacteriana contra 83,3% das bactérias analisadas. Para 66,7% das bactérias, as pastas de própolis apresentaram maior atividade antibacteriana que o hidróxido de cálcio, e este foi mais efetivo apenas para Streptococcus mutans (ATCC 25175), Staphylococcus aureus (ATCC 25923) e Pseudomonas aeruginosa (ATCC 27853). De acordo com a metodologia utilizada, pode-se concluir que as pastas experimentais A70D e D70D apresentam boa atividade contra bactérias aeróbias, sendo superior ao hidróxido de cálcio
Shaping ability of Reciproc and TF Adaptive systems in severely curved canals of rapid microCT-based prototyping molar replicas
Objective: To evaluate the shaping ability of Reciproc and Twisted-File Adaptive systems in rapid prototyping replicas. Material and Methods: Two mandibular molars showing S-shaped and 62-degree curvatures in the mesial root were scanned by using a microcomputed tomography (μCT) system. The data were exported in the stereolitograhic format and 20 samples of each molar were printed at 16 µm resolution. The mesial canals of 10 replicas of each specimen were prepared with each system. Transportation was measured by overlapping radiographs taken before and after preparation and resin thickness after instrumentation was measured by μCT. Results: Both systems maintained the original shape of the apical third in both anatomies (P>;0.05). Overall, considering the resin thickness in the 62-degree replicas, no statistical difference was found between the systems (P>;0.05). In the S-shaped curvature replica, Reciproc significantly decreased the thickness of the resin walls in comparison with TF Adaptive. Conclusions: The evaluated systems were able to maintain the original shape at the apical third of severely curved mesial canals of molar replicas
Radiographic analysis of root canal fillings: influence of two sealers on the perception of voids
The aim of this ex vivo was to investigate if two radiopaque root canal sealers with different formulations would influence the radiographic perception of root canal fillings. The root canals of 48 extracted maxillary canines were prepared and randomly assigned to 3 groups of 16 specimens each. In each group, the root canals were filled by lateral condensation of gutta-percha and one of the tested sealers: Endométhasone, Sealer 26, or a non-radiopaque sealer. A through-and-through void was simulated in half of the specimens from each group (n=8). The buccolingual radiographic images obtained were randomly interpreted for voids existence by a radiologist and an endodontist. The differences in sensitivity and specificity between groups and examiners were compared using, respectively, Fisher's Exact and McNemar tests at 5% significance level. Both radiopaque sealers caused a significant decrease in sensitivity at the coronal part of fillings. The use of Endométhasone increased specificity values for both coronal and apical portions of the root canal fillings. In conclusion, the tested sealers influenced the radiographic perceptions of laterally condensed root canal fillings in a different way.O propósito deste estudo ex vivo foi investigar se dois cimentos obturadores de fórmulas diferentes influenciariam a percepção radiográfica de obturações de canais radiculares. Os canais radiculares de 48 caninos superiores extraídos foram preparados e divididos em 3 grupos. Em cada grupo os canais foram preenchidos através da condensação lateral da guta-percha e de um dos cimentos testados (Endométhasone, Sealer 26 e cimento não-radiopaco), e um defeito de ponta a ponta foi simulado em metade dos espécimes de cada grupo (n=8). As imagens radiográficas vestíbulo-linguais obtidas foram aleatoriamente interpretadas quanto à existência de defeitos por um radiologista e um endodontista. As diferenças em sensibilidade e especificidade entre os grupos e examinadores foram comparadas respectivamente usando-se os testes Exato de Fisher e McNemar ajustados ao nível de significância de 5%. Ambos os cimentos radiopacos ocasionaram uma redução significativa da sensibilidade na parte cervical das obturações. O uso do Endométhasone aumentou os valores de especificidade para as porções cervical e apical das obturações dos canais radiculares. Concluiu-se que os cimentos testados influenciaram de maneira distinta a percepção radiográfica de obturações endodônticas executadas com condensação lateral
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