Irrigation trends among members of the Chilean Endodontic Society

Introduction: the aim of this study is to determine the current trends of irrigation during root canal therapy by specialists who are members of the Chilean Endodontic Society. materials and method: a survey (survey monkey -SurveyMonkey.com) was e-mailed to the 485 members of the Chilean Endodontic Society. the instrument was translated and adapted from the survey "irrigation trends among American Association of Endodontists members: a web-based survey" applied in the USA in 2012. participants answered a set of 16 questions that included irrigant selection, irrigant concentration, the adopted protocol, techniques or devices for irrigant activation. results: 99 percent of respondents use sodium hypochlorite as the main irrigant. data indicate that 74 percent of respondents use hypochlorite at a concentration of 5 percent. most respondents (94 percent) also include EDTA in their usual practice. In addition, 90 percent of respondents reported that they activate the irrigating agent, and 94 percent confirmed that they perform a final irrigation protocol. conclusion: the majority of respondents use sodium hypochlorite as the main irrigant at a concentration of 5 percent, use ethylenediaminetetraacetic acid (EDTA) as a smear removal agent, activate the irrigant, and perform a final irrigation protocol.

Use of EDTA in the treatment of local tissue damage caused by the Bothrops alternatus venom / Utilização do EDTA no tratamento da lesão tecidual local causado pelo veneno de Bothrops alternatus

Twelve adult rabbits were distributed in three groups and received on the femoral biceps region, via intradermal injection (ID), 25µg of Bothrops alternatus venom dissolved in NaCl 0.9% and diluted in 0.25mL of phosphate buffered saline (PBS). Thirty minutes later, the group G1 received 0.25mL of phosphate buffered saline (PBS) ID while to G2 and G3 25mg of ethylenediamine tetraacetic acid (EDTA) dissolved in 0.25mL of PBS were administered via intramuscular (IM) and intravenous (IV) injection, respectively. Evaluations included local lesion and blood profile of all animals, before (time zero) and at 1, 2, 3, 4, 5, 6, 12, 18 and 24h after venom administration. All animal treated with PBS (G1) and EDTA IV (G3) presented increase of nociceptive stimuli at the site of inoculation of the venom, followed by moderate edema that persisted for 24h. Animals treated with IM EDTA (G2) only manifested increase of nociceptive stimuli at the site of injection 1h after treatment with discrete local edema between 12 and 24h. In relation to the local hemorrhagic halo no differences were found amongst the studied groups. Blood profile revealed significant decrease of segmented neutrophils in all groups. There was also increase in triglycerides and decrease in total protein and albumin in all groups. The local lesion was not altered by the treatments.(AU)

Doze coelhos adultos, distribuídos em três grupos, receberam, na região de bíceps femoral, por via intradérmica (ID), 25µg de veneno de Bothrops alternatus, dissolvidos em NaCl 09%, diluído em 0,25mL de tampão salina fosfato (PBS). Trinta minutos após o desafio, o grupo G1 recebeu 0,25mL de (PBS) ID, e os grupos G2 e G3 receberam 25mg de ácido etilenodiamino tetra-acético (EDTA), dissolvidos em mL de PBS por via intramuscular (IM) e intravenosa (IV), respectivamente. Foram avaliados lesão local e perfil sanguíneo de todos os animais, antes - tempo zero, e à uma, às duas, três, quatro, cinco, seis, 12, 18 e 24 horas após a injeção do veneno. Tanto os animais tratados com PBS (G1) como os animais tratados com EDTA IV (G3) apresentaram aumento do estímulo nociceptivo no local da administração do veneno, seguido por moderado edema, que perdurou por 24h. Os animais tratados com EDTA IM (G2) somente manifestaram aumento do estímulo nociceptivo local uma hora após tratamento e discreto edema local entre 12 e 24 horas. Em relação ao halo hemorrágico, não houve diferença entre os três grupos estudados. No perfil hematológico, observou-se diminuição significativa dos neutrófilos segmentados nos três grupos estudados. Da mesma forma, houve aumento dos triglicerídeos e diminuição da proteína total e albumina em todos os grupos. Conclui-se que a lesão local não foi alterada pelos tratamentos.(AU)

Can intra-radicular cleaning protocols increase the retention of fiberglass posts? A systematic review

Abstract The presence of residues within the root canal after post-space preparation can influence the bond strength between resin cement and root dentin when using fiberglass posts (FGPs). Currently, there is no consensus in the literature regarding what is the best solution for the removal of debris after post-space preparation. This systematic review involved "in vitro" studies to investigate if cleaning methods of the root canal after post-space preparation can increase the retention of FGPs evaluated by the push-out test. Searches were carried out in PubMed (MEDLINE) and Scopus databases up to July2017. English language studies published from 2007 to July 2017 were selected. 475 studies were found, and 9 were included in this review. Information from the 9 studies were collected regarding the number of samples, storage method after extraction, root canal preparation, method of post-space preparation, endodontic sealer, resin cement, cleaning methods after post-space and presence of irrigant activation. Five studies presented the best results for the association of sodium hypochlorite (NaOCl) and ethylenediamine tetra-acetic acid (EDTA), while in the other 4 studies, the solutions that showed improved retention of FGPs were photon-induced photoacoustic streaming (PIPS), Qmix, Sikko and EDTA. The results showed heterogeneity in all comparisons due to a high variety of information about cleaning methods, different concentrations, application time, type of adhesive system and resin cements used. In conclusion, this review suggests that the use of NaOCl/EDTA results in the retention of FGPs and may thus be recommended as a post-space cleaning method influencing the luting procedure.

Regeneración tisular guiada en defecto óseo de 3 paredes: enfermedad periodontal y oclusión / Guided tissue regeneration and in a three-walled osseous defect: periodontal disease and occlusion

Relacionar la importancia del éxito en regeneración tisular guiada y el correcto diagnóstico del problema, en este caso enfermedad periodontaly un contacto prematuro en ORC producto de una obturación de amalgama incorrecta. Caso clínico: tratamiento de un defecto infraóseo de3 paredes mediante la utilización de hueso de origen bovino particulado junto con proteínas derivadas de la matriz del esmalte. Tanto los parámetros clínicoscomo los radiográficos fueron evaluados al inicio, en el postquirúrgico inmediato y a los 12 meses. Conclusión: se observó un alto grado de regeneración pasados los 12 meses del tratamiento. Parecería no ser siempre necesaria la utilización de membrana colágena. Las proteínas derivadas de la matrizdel esmalte serían un sustituto de la membrana en algunos casos. Resulta fundamental el chequeo de la situación oclusal en piezas periodontalmente comprometidas...

Effects of various irrigation/aspiration protocols on cleaning of flattened root canals

This study aimed to evaluate, by means of scanning electron microscopy (SEM), the cleaning of flattened root canals, varying irrigation/aspiration protocols during biomechanical preparation. Thirdy human mandibular incisors were distributed into three groups (n = 10) according to the aspiration/irrigation protocols: conventional, conventional + brush, and apical negative pressure irrigation. Irrigation procedure was performed with 5 mL of 1% NaOCl at each change of instrument; final irrigation was conducted with 17% EDTA for 5 min. After biomechanical preparation, the roots were sectioned and prepared for SEM analysis. The images obtained were evaluated under 35× and 1,000× magnification by three calibrated examiners, following a double-blind design. All data were analyzed using Kruskal–Wallis and Dunn’s post hoctests (α = 0.05). Canals wherein the conventional method and apical negative pressure irrigation were employed revealed less debris, statistically different from the conventional + brush group (p < 0.05). Regarding the presence of smears, apical negative pressure irrigation was more effective in cleaning, showing lowest scores (p < 0.05), compared with the other tested protocols. Comparing each root canal third revealed that the apical portion was difficult to clean as all the tested protocols showed similar high scores (p > 0.05), both for the presence of debris and smear layer. In conclusion, although none of the studied irrigation/aspiration protocols have completely cleaned flattened root canals, apical negative pressure irrigation was more effective in smear layer removal, whereas the conventional + brush protocol was the least effective in removing the debris and smear layer.

Relation between Calcium Loss and Its Effect on Microhardness of Root Canal Dentin Following Treatment With 17% Ethylene Diamine Tetraacetic Acid(EDTA) at Different Time Intervals: An Ex-Vivo Study.

Decalcification and its effect on microhardness of root canal dentin by an aqueous solution of 17% EDTA at different time intervals were studied.Single rooted forty extracted human premolar teeth after adequate processing and embedded with acrylic resin were randomly divided into 8 groups based on different time intervals. Each sample group was assessed for Ca²⁺ release into the test solution by Atomic Absorption Spectrophotometer, respectively and then were subjected for microhardness testing.17% EDTA and 0.9% Saline, test solutions were used; EDTA was adjusted to 7.5 pH. Data analysis was done by One Way analysis of variance (ANOVA) and the comparison of means was done by using Tukey’s multiple comparison tests. The decalcifying activity of 17% EDTA solution was time dependent and increased immersion time showing very high significant influence on the amount of calcium extracted (<strong>F=154.304, p). The reduction in microhardness for 17% EDTA solution was time dependent and increased immersion time showing very high significant decrease in the microhardness among the different time intervals tested (<strong>F=249.925, p < 0.0005</strong>).Effect of 17 % EDTA solution as root canal irrigant is time dependent as evidenced by dentin microhardness reduction.

Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

Objective: The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and Methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI - 2.5% NaOCl, GII - 2% chlorhexidine (CHX) gel, and GIII - saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After S2, significant median percentage reduction was observed in all groups, irrespective of the irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p<0.05). Root canal rinse with 17% EDTA (S3) for a 3-minute period failed to decrease endotoxin levels in GI and a slight decrease was observed in GII (59%) and GIII (61.1%) (all p>0.05). Intracanal medication for 30 days was able to significantly reduce residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII, p<0.05). No differences were found in the endotoxin reduction when comparing s2 and s4 treatment groups. Conclusion: Our findings demonstrated the effectiveness of the mechanical action of the instruments along with the flow and backflow of irrigant enduring root canal instrumentation for the endotoxin removal from root canals of teeth with chronic apical periodontitis. Moreover, the use of intracanal medication for 30 days contributed for an improvement ...

Smear layer removal efficacy of different irrigating solutions: A comparative scanning electron microscope evaluation.

Aims: Comparative evaluation of cleaning efficacy of smear layer removal by different irrigating solutions such as 2.5% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA) with 2.5% NaOCl, 10% citric acid with 2.5% NaOCl and 1% tetracycline Hydrochloride (HCl) with 2.5% NaOCl for smear layer removal in the apical third of root canal. Settings and Design: In vitro material science study. Materials and Methods: Seventy-five single rooted permanent maxillary central incisor teeth were subjected to standardized root canal instrumentation (crown down technique). The teeth were randomly divided into five groups with 15 teeth in each groups: (1) Normal saline (n = 15) (2) 2.5% NaOCl (n = 15) (3) 17% EDTA + 2.5% NaOCl (n = 15) (4) 10% citric acid + 2.5% NaOCl (n = 15) (5) 1.0% tetracycline HCL + 2.5% NaOCl (n = 15). After final irrigation, the teeth were prepared for scanning electron microscope analysis to evaluate the cleaning of apical third of radicular dentine to determine the presence or absence of smear layer. Statistical Analysis Used: The results were analyzed by nonparametric statistical analysis techniques. Kruskal-Wallis test, Mann-Whitney test and Chi-square tests were carried out. Results: There was no significant statistical difference in the efficacy of smear layer removal when 2.5% NaOCl was compared with 17% EDTA with 2.5% NaOCl, 10% citric acid with 2.5% NaOCl and 1% tetracycline HCl with 2.5% NaOCl in apical third of root canals. Conclusions: The present study suggests that irrigating agents, citric acid and tetracycline HCl can be used as an alternative to EDTA for the removal of smear layer in endodontics.

Blood clot stabilization on root dentin conditioned by the combination of tetracycline and EDTA

AIM: To assess the combined use of tetracycline (TTC) and ethylenediaminetetraacetic acid (EDTA) on clot formation, considering that EDTA may neutralize TTC acidity. METHODS: Planed human tooth roots were treated with saline solution, EDTA, TTC and their combination (EDTA followed by TTC and TTC before EDTA). Fresh human blood was applied on the conditioned surfaces to check clot adhesion and stabilization. A previously calibrated (kappa = 0.93) and blinded examiner scored scanning electron micrographs of the samples. Statistical analyses were performed using one-way ANOVA and Tukey's test. RESULTS: Application of TTC before EDTA presented the best results with the highest number of cells adhered to the root surface (p=0.046). Use of EDTA alone and EDTA before TTC disturbed clot stabilization when compared to control group (p<0.01). CONCLUSIONS: The use of TTC before EDTA seems to be able to keep blood cells viable to establish an organized clot and could be used by clinicians together with the conventional mechanical root scaling and planing...

Effectiveness of a Canal Brush on Removing Smear Layer: A Scanning Electron Microscopic Study

This study evaluated the effectiveness of a highly flexible endodontic brush made of polypropylene canal brush (CanalBrush; Coltène) on smear layer removal from the canal walls when used according to the manufacturer's recommendations. Forty-four single-rooted mandibular incisors were prepared to apical size 30/0.06 and randomly divided into three groups A, B and C, where the final irrigation regimen was 10 mL 17% EDTA and 10 mL 2.5% NaOCl for group A, 10 mL EDTA, 5 mL NaOCl, CanalBrush for 20 s at 450 rpm and 5 mL NaOCl for group B, 10 mL NaOCl, CanalBrush and 10 mL NaOCl for group C. One medium-sized CanalBrush was used for each root canal and all brushes were examined under the optical microscope after application to evaluate bristle deformation. Afterwards, roots were split longitudinally and the presence of smear layer was evaluated under a scanning electron microscope. Used brushes invariably exhibited bristle deformation. Group C exhibited the highest means of smear layer in all thirds. Comparing the apical thirds in all groups, there was no statistical difference between groups A and B (3.64±0.48 and 3.68±0.62 respectively), while group C exhibited significantly higher scores (3.9±0.28) than the other two groups. In conclusion, the CanalBrush proved unable to remove smear layer from the instrumented root canals, when used according to the manufacturers' instructions.

O objetivo deste estudo foi avaliar a eficácia de um escova intra-canal (CanalBrush, Coltène) na remoção da smear layer das paredes do canal radicular, quando usada de acordo com as instruções do fabricante. Quarenta e quatro incisivos mandibulares unirradiculares foram instrumentados até o ápice com instrumentos 30/0.06 e aleatoriamente distribuidos em três grupos A, B e C, com regime de irrigação final de 10 mL a 17% EDTA e 10 mL NaOCl a 2,5% para o Grupo A; irrigação final de 10 mL EDTA, 5 mL NaOCl, uso da escovinha CanalBrush por 20 s a 450 rpm e 5 mL NaOCl para o Grupo B e 10 mL NaOCl, uso da escovinha CanalBrush e 10 mL NaOCl para o Grupo C. Foi utilizada escovinha CanalBrush de tamanho médio para cada canal e todas elas foram examinadas em microscópio para avaliação da deformação de cerdas. Depois as raízes foram cortadas longitudinalmente e a presença da smear layer foi avaliada por microscópio eletrônico de varredura. As escovinhas usadas apresentaram todas alguma deformação das cerdas. No Grupo C foi observada a maior média de área de smear layer em todos os terços dentais. Na comparação dos terços apicais de todos os grupos não houve diferença significativa entre os grupos A e B (3,64±0.48 e 3,68±0,62, respectivamente), enquanto que o Grupo C mostrou escores significativamente mais altos(3,9±0.28) que os outros dois grupos. Concluindo, a escovinha CanalBrush mostrou ser incapaz de remover a smear layer dos canais instrumentados, quando usada de acordo com as instruções do fabricante.

Intra-radicular dentin treatments and retention of fiber posts with self-adhesive resin cements

The aim of this study was to evaluate the effect of treating intraradicular dentin with irrigating solutions on the retention of glass-fiber posts luted with self-adhesive resin cement. Bovine incisors were endodontically treated, and 9-mm-deep postholes were prepared. Before inserting the cement, the root canals were irrigated with various solutions: 11.5% polyacrylic acid for 30 s, 17% EDTA for 60 s, or 5% NaOCl for 60 s, respectively. Irrigation with distilled water was used in the control group. After all specimens had been rinsed with distilled water, the excess moisture was removed and the posts were luted using either BisCem (Bisco) or RelyX Unicem clicker (3M ESPE). Seven days after luting, the specimens were sectioned transversally into 1-mm-thick slices, which were submitted to push-out testing on a mechanical testing machine. Bond strength data (n = 6 per group) were analyzed by two-way ANOVA and Student-Newman-Keuls' test (α = 0.05). For Unicem, EDTA showed lower bond strength than the other solutions, which had similar results. For BisCem, EDTA showed higher bond strength than the other treatments, while application of NaOCl yielded higher bond strength than polyacrylic acid whereas the control group had intermediate results. In conclusion, irrigating root canals before insertion of self-adhesive resin cements, especially EDTA, might interfere with retention of the fiber posts.

Cleaning the apical third of curved canals after different irrigation protocols

This study evaluated the protocols of sonic and vacuum irrigation regarding the capacity of debris removal from root canal systems. Canal preparations were carried out on 30 mandibular first molars using the ProTaper Universal System. Teeth were divided into two experimental groups (n=15): Group 1: sonic irrigation and Group 2: vacuum irrigation protocol. Subsequently, the mesial roots were sectioned and observed by stereomicroscopy and scanning electron microscopy. Three independent examiners evaluated images of the apical thirds according to the following scores: 1= small presence of debris, 2= moderate presence of debris, and 3= dense presence of debris. Data were analyzed with ANOVA and Kruskal-Wallis tests (α=0.05). Comparison among the groups revealed that at the apical third, the root halves of Group 1 had significantly less surface debris (p=0.002) than those of Group 2. However, at 2 mm from the working length, Group 2's specimens showed less remaining debris in approximately 75% of the analyzed root canals. At the whole apical third, the sonic irrigation protocol removed significantly more debris than the vacuum protocol. However, in the region at 2 mm from the working length, the second irrigation method demonstrated a better performance.

Este estudo avaliou protocolos de irrigação sônica e a vácuo em relação à capacidade de remoção de debris do sistema de canais radiculares. Trinta primeiros molares mandibulares tiveram seus canais radiculares preparados pela utilização do Sistema ProTaper Universal. Os dentes foram divididos em dois grupos experimentais (n=15): Grupo 1: protocolo de irrigação sônica, e Grupo 2: protocolo de irrigação a vácuo. Posteriormente, as raízes mesiais foram seccionadas e observadas em lupa estereoscópica e microscopia eletrônica de varredura. Três examinadores independentes avaliaram as imagens do terço apical de acordo com as seguintes pontuações: 1. pequena presença de debris; 2: moderada presença de debris; e 3. densa presença de debris. Os dados foram analisados pelos testes estatísticos ANOVA e Kruskal-Wallis (α=0,05). A comparação entre os grupos revelou que, no terço apical, as hemissecções radiculares do Grupo 1 apresentaram debris remanescentes de forma significativamente menor (p=0,002) do que as do Grupo 2. No entanto, a 2 mm do comprimento de trabalho, as amostras do Grupo 2 mostraram menos debris remanescentes em aproximadamente 75% dos canais radiculares analisados. Considerando todo o terço apical, o protocolo de irrigação sônica removeu significativamente mais debris do que o protocolo de irrigação a vácuo. No entanto, na região a 2 mm do comprimento de trabalho, o segundo método de irrigação demonstrou um melhor desempenho.

Efecto del grabado de la dentina radicular con ácido dietilenoaminotetra acético (EDTA) en la resistencia de unión de cementos autoadhesivos y autograbantes / Effect of engraving dietilenoaminotetra acetic acid (EDTA) root dentin in the resistance of cemented joints stickers and etching

Fue evaluado el efecto del grabado de la dentina radicular con EDTA en la resistencia de unión (RU) inmediata (IM) y después de termociclaje (TM) de un cemento autoadhesivo (AA) y uno auto grabador (AG) para la cementación de postes de fibra de vidrio. Fueron utilizadas 40 raíces de premolares humanos divididas en 4 grupos según tipo de cementación (n=10) G1 RelyX U100 (UC) según indicaciones del fabricante(IF); G2 grabado con EDTA 24% por 60 s antes de la aplicación del UC ; G3 Para Post Para Core Automix (PC) (IF)G4 - grabado con EDTA 24% por 60 s antes de la aplicación del (PC).Las raíces fueron cortadas en discos de 1 mm (dos discos por tercio radicular), la mitad de los discos fueron sometidos a ensayo expulsión IM (0,5mm/min) y la otra mitad después de TM (5º C e 55º C).los datos fueron analizados en test de ANOVA y Tukey (?=0,05).dando como resultado que el grabado con EDTA altero negativamente los valores de RU solo del tercio cervical en los dos cementos. Cuando fue comparado TM con IM con o sin aplicación de EDTA no se encontraron diferencias estadísticas significativas. Para todos los grupos testados.El cemento PC obtuvo mayores valores de RU (19,59 MPa) comparado con el UC (15,80 MPa).concluyéndose que el tratamiento con EDTA afecto la RU solo para el tercio cervical tanto en IM como TM en los dos cementos. El TM con o sin EDTA no afecto los valores de RU cuando comparado con IM

The effect of post-space treatment whit EDTA on the bond strength (BS) of fiber posts in different root regions was evaluated using two different type of resin cements Rely X U100 (UC) and Para Post Para Core automix (PC) . Fourty extracted premolars root canals were assigned to four groups of 10 roots each. G1 RelyX U100 (UC) according to manufacturer's instructions (MI), G2 etching whit EDTA 24% for 60 s before application of UC; G3 Para Post Para Core Automix (PC) MI; G4 Etching whit EDTA 24% for 60s before application off PC. After cementation the roots were sectioned in 6 slices 1mm each (two slides for root region) and randomly divided into two subgroups, depending on testing time immediate (IM) vs. after termocicling(TM) ), for expulsion test. Statistical analysis was performed with ANOVA and Tukey test (?=.05) No differences in BS was found among the groups whit and whit out EDTA 24 %. Etching whit EDTA adversely alter the BS values of the cervical third in the two cements. When TM was compared with IM with or without application of EDTA there was no statistically significant difference. For all groups tested, PC show higher values of BS (19.59 MPa) was compared with UC (15.80 MPa). Concluded that treatment with EDTA affected the BS only on the cervical third in both IM and TM in the two cements. The TM with or without EDTA did not affect the values of BS when compared with IM

A SEM evaluation of dentinal adaptation of root canal obturation with GuttaFlow and conventional obturating material.

Objective: The aim of this in-vitro study was to compare dentinal adaptation of conventional obturating material and GuttaFlow in young permanent teeth of child patients. Materials and Methods: Ten young permanent anterior teeth with closed foramen were selected for the study. Root canal preparations were carried out using a step back technique. The canal was alternately irrigated with 5.25% sodium hypochlorite solution and 17% EDTA and normal saline. After root canal preparation specimens were randomly divided into two groups (n=5). GROUP "A": Obturated with zinc-oxide eugenol sealer and gutta-percha cone using cold lateral obturation technique. GROUP "B": Obturated with GuttaFlow as per the manufacturer's instruction. The teeth were split into two halves. Five randomly chosen longitudinal split teeth samples each from Group "A" and Group "B" was observed under scanning electron microscope to access the interface between obturating material and dentin at the level of 2 mm from the apex. Results: On statistical analysis the dentinal adaptation (μm) of Group A was observed with a mean of 0.52 and standard deviation 0.15, while the value of mean and standard deviation were noted 0.12 and 0.02 for Group B. The "t" value on comparison of Group A and Group B is 5.79 with "P " value of <0.001, which is highly significant. Conclusion: From result of the study it can be concluded Group B samples showed significantly superior seal when compared with Group A. Complete seal was not observed in any of Group A samples.

Microscope-aided endodontic treatment of maxillary first premolars with three roots: A case series.

Maxillary premolars have a highly variable root canal morphology. However, the presence of three roots is a rare occurrence. This clinical article describes the unusual anatomy detected in maxillary premolars during routine endodontic treatment using microscope. The diagnosis and clinical management of maxillary first premolars with three roots and canals using radiographic interpretation, access cavity modification and visual enhancement with operative microscopes is discussed in the article.

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.

CT evaluation of apical canal transportation associated with stainless steel hand files, oscillatory technique and ProTaper rotary system

This study used computed tomography (CT) to compare apical canal transportation in mesiobuccal canals of maxillary molars prepared with different techniques. Sixty teeth were assigned to 3 groups (n=20), according to the technique used for root canal instrumentation: hand instrumentation with K-Flexofiles, K-Flexofiles activated by an oscillatory system and ProTaper NiTi rotary system. Pre and post-instrumentation CT images were obtained 3 mm short of the apical foramen and were superimposed to compare canal transportation. Data were analyzed statistically by ANOVA and Tukey's test using the SPSS software (α=0.05). In the buccal direction, the manual technique produced significantly less canal transportation than the oscillatory technique (p<0.05) and both were similar to the rotary technique (p>0.05). In the distal and distopalatal directions, the oscillatory technique produced more canal transportation (p<0.05). In the mesiopalatal direction, the oscillatory technique produced more canal transportation than the manual technique (p<0.05), and both were similar to the rotary technique (p>0.05). In conclusion, all techniques produced canal transportation, and the oscillatory technique produced the greatest removal of root dentin toward the innerside of the root curvature.

Este estudo utilizou a tomografia computadorizada (TC) para comparar o transporte do canal radicular nos canais mésio-vestibulares de molares superiores preparados por diferentes técnicas. Sessenta molares superiores foram divididos em 3 grupos (n=20) de acordo com a técnica utilizada para o preparo do canal radicular: instrumentação manual com limas K-Flexofile, limas K-Flexofile acopladas a um sistema oscilatório e sistema rotatório ProTaper. Imagens de TC pré e pós-instrumentação foram obtidas 3 mm aquém do forame apical e superpostas para comparar o transporte do canal. Os dados foram analisados estatisticamente pela Análise de Variância (ANOVA) e Teste de Tukey utilizando o software SPSS (α=0,05). Na direção vestibular, a técnica manual produziu significantemente menos transporte do canal radicular do que a técnica oscilatória (p<0,05) e ambas foram similares a técnica rotatória (p>0,05). Nas direções distal e disto-palatina, a técnica oscilatória produziu mais transporte do canal radicular (p<0,05). Na direção mésio-palatina, a técnica oscilatória produziu mais transporte do canal radicular do que a técnica manual (p<0,05), sendo que ambas foram similares à técnica rotatória (p>0,05). Em conclusão, todas as técnicas produziram transporte do canal radicular e a técnica oscilatória produziu os maiores desgastes de dentina na direção interna da curvatura.

Apical microleakage and SEM analysis of dentin surface after 980 nm diode laser irradiation

This study evaluated the effect of 980-nm diode laser on apical microleakage and intraradicular dentin morphology. Roots of 110 mandibular incisors were used in the study: 92 for microleakage test and 18 for scanning electron microscopy (SEM). Roots were randomly assigned to 3 groups according to the irrigating solution (water, NaOCl and NaOCl/EDTA) and were divided into 3 subgroups according to the laser irradiation protocol (without irradiation, irradiated at 1.5 W and irradiated at 3.0 W). Two specimens of each subgroup were prepared for SEM. The remaining roots were filled with AH Plus and gutta-percha. Apical leakage was assessed by ink penetration and data were analyzed statistically by ANOVA and Tukey-Krammer test (α=0.05). SEM analysis showed intensification of changes with increase of laser power as well as variations according to the irrigating solution. Modified smear layer was observed in specimens treated with water and irradiated with laser. Roots irrigated with NaOCl/EDTA had lower levels of infiltration (0.17 ± 0.18 mm) differing significantly (p<0.05) from those of roots irrigated with water (0.34 ± 0.30 mm), but similar (p>0.05) to those irrigated with NaOCl (0.28 ± 0.29 mm). Non-irradiated roots had lower levels of infiltration (0.10 ± 0.14 mm), differing (p<0.05) from those irradiated at 1.5 W (0.32 ± 0.22 mm) and 3.0 W (0.37 ± 0.32 mm). The 980 nm diode laser modified dentin morphology and increased apical microleakage.

Este estudo avaliou o efeito do laser de diodo 980 nm na microinfiltração apical e na morfologia intrarradicular da dentina. Raízes de 110 incisivos inferiores foram utilizadas no estudo: 92 para o teste de microinfiltração e 18 para microscopia eletrônica de varredura (MEV). As raízes foram divididas em 3 grupos de acordo com a solução irrigante (água, NaOCl e NaOCl/EDTA) e subdivididas em 3 de acordo com a irradiação laser (sem irradiação, irradiados com 1,5 W e irradiados com 3,0 W). Duas amostras de cada subgrupo foram preparadas para MEV. As raízes restantes foram preenchidas com AH Plus e guta percha. A infiltração apical foi avaliada nas raízes por meio da penetração do corante e os dados foram analisados por ANOVA e teste de Tukey-Krammer (α=0,05). Os resultados da MEV mostraram intensificação das mudanças quando se aumentou a potência do laser e variações de acordo com a solução irrigadora. Camada de smear modificada foi observada em espécimes tratados com água e irradiados com laser. Raízes irrigadas com NaOCl/EDTA tiveram níveis menores de infiltração (0,17 ± 0,18 mm) estatisticamente diferente (p<0,05) das raízes irrigadas com água (0,34 ± 0,30 mm), mas semelhante (p>0,05) aos irrigados com NaOCl (0,28 ± 0,29 mm). As raízes não irradiadas tiveram níveis menores de infiltração (0,10 ± 0,14 mm), diferente (p<0,05) de 1,5 W (0,32 ± 0,22 mm) e 3.0 W (0,37 ± 0,32 mm). O laser de diodo 980 nm alterou a morfologia da dentina e aumentou a infiltração marginal apical.

Evaluación de los efectos del EDTA sobre el barro dentinario en la dentina radicular, en distintos períodos de tiempo: un estudio con microscopía electrónica de barrido / Evaluation of the effect of EDTA on the smear layer in the radicular dentin, in different application times: a scanning electron microscopic study

El objetivo de este estudio fue evaluar la eliminación del barro dentinario del conducto radicular luego de la irrigación con EDTA en diferentes tiempos. Se instrumentaron 100 premolares inferiores y se dividieron en 5 grupos de 20 cada uno. El grupo control fue irrigado con suero fisiológico solamente. Los grupos restantes fueron irrgados con hipoclorito de sodio al 2,5 %. El grupo 1 se irrigó con EDTA dejando la solución 1 minuto en el interior, en el grupo 2 el EDTA se dejó 3 minutos, en el grupo 3 se dejó 5 minutos y en el grupo 4 se dejó 8 minutos y posteriormente todos los grupos fueron irrgados con hipoclorito de sodio. Las raíces fueron separadas longitudinalmente en dos mitades y llevadas al MEB para observar presencia o ausencia de túbulos dentinarios. Los resultados demostraron que el tiempo ideal para la eliminación del barro dentinario fue de 5 minutos y el tercio con mayor limpieza fue el tercio medio.

Combined Ethylenediaminetetraacetic Acid Chelation, Phototherapeutic Keratectomy and Amniotic Membrane Transplantation for Treatment of Band Keratopathy

PURPOSE: The objective of this study is to evaluate the therapeutic efficacy of ethylenediaminetetraacetic acid (EDTA) chelation and excimer laser phototherapeutic keratectomy (PTK) combined with amniotic membrane transplantation (AMT) for the treatment of band keratopathy (BK). METHODS: Eleven eyes in ten patients with BK received combined PTK (ablation zone of central 7.0-7.5 mm, depth of 50 microm), EDTA chelation (0.05 M, 3 minutes), and amniotic membrane transplantation using fibrin glue. Preand postoperative best corrected visual acuities, symptom changes, reepithelialization time, cosmesis, recurrence, and complications were analyzed. RESULTS: Visual acuity improved in three eyes (27.3%) and did not change in eight eyes (72.7%). Symptoms improved in all patients, and the mean reepithelialization time was 10.6+/-5.3 days. The cosmetic results were good in eight eyes (72.7%) and were fair in three eyes (27.3%). During the mean follow-up period of 11.4+/-6.1 months (range, 6 to 23 months), no postoperative complications or recurrences were observed. CONCLUSIONS: The combination of EDTA chelation, PTK, and AMT is safe and effective for the treatment of band keratopathy.