Laser therapy as an adjunct in the treatment of sodium hypochlorite extrusion through a root perforation: a case report.

Accidental sodium hypochlorite extrusion can occur during endodontic irrigation procedures. The symptoms appear immediately and include severe pain, swelling, and probable tissue necrosis adjacent to the root of the treated tooth. Treatment of sodium hypochlorite extrusion involves immediate and copious saline irrigation to neutralize the area and prescription of analgesic, anti-inflammatory, and antibiotic medications. Low-level laser therapy (LLLT) might be useful as an adjuvant treatment for damaged soft tissues to improve healing. This case report describes the treatment of accidental extrusion of 1% sodium hypochlorite through a root canal perforation in a mandibular incisor during endodontic treatment. The extrusion caused minor swelling within the mentolabial sulcus and a large area of necrosis in the gingivolabial mucosa and right edentulous premolar area. Conventional treatment was performed in association with LLLT. Clinical and radiographic examinations after 6 months showed complete healing of the necrotic area without paresthesia and the repair of apical tissues.

The Influence of Humidity on Intra-tubular Penetration and Bond Strength of AH Plus and MTA Fillapex: An In Vitro Study.

OBJECTIVE: The aim of this study was to evaluate the influence of humidity on the intra-tubular penetration, bond strength and failure mode associated with AH Plus (AH) and MTA Fillapex (MTAF) sealers. METHODS: For this analysis, an apparatus was created to maintain the humidity of the specimens. Sixty bovine single-rooted teeth with similar anatomy were used. The teeth were randomly divided into 4 groups (n=15): G1 - AH/moist, G2 - AH/dry, G3 - MTAF/moist and G4 - MTAF/dry. A laser scanning confocal microscope was used to analyse the penetrability of the sealers into the dentinal tubules. A push-out test was performed to examine the diameter and height of the root canal fillings. The failure mode was analysed under a stereomicroscope at 40× magnification. The data were submitted to non-parametric Kruskal-Wallis and Dunn's tests. The significance level was P<0.05. RESULTS: The MTAF sealer exhibited higher intra-tubular penetration values compared to AH Plus (P<0.05) sealer. AH Plus showed the highest bond strength values. Regarding the type of failure mode, a majority of cohesive failures was identified, irrespective of the moisture conditions, which were not statistically significant among the sealers (P<0.05). CONCLUSION: Humidity conditions did not influence the intra-tubular penetration, bond strength and failure mode of AH Plus and MTAF sealers.

Evaluation of Physicochemical Properties of a New Root Canal Sealer.

INTRODUCTION: The aim of this study was to evaluate some of the physicochemical properties of a new root canal sealer. METHODS: The sealers tested were Sealer Plus compared with AH Plus. For the radiopacity, flow, solubility, and fabrication of test specimens relative to setting times, the American National Standards Institute/American Dental Association No. 57 (2000) and International Organization for Standardization 6876 (2012) specifications were followed. To measure the initial and final setting times, the ASTM C266/2008 standard was used. pH was evaluated in the time intervals of 3, 24, 72, and 168 hours. Statistical tests were applied to the results obtained at a level of significance of 5%. RESULTS: The results demonstrated that the Sealer Plus sealer showed a lower radiopacity value than AH Plus sealer (P < .05); however, this was higher than the minimum value recommended by the specifications (ie, 3 mm Al). Relative to flow, the value for Sealer Plus was 19.19 mm and for AH Plus, 19.81 mm (P > .05). Sealer Plus presented initial and final setting times of 138 minutes and 210 minutes, respectively, whereas the values for AH Plus were 437 minutes and 849 minutes, respectively (P < .05). Relative to solubility, Sealer Plus presented 0.21% and AH Plus, 0.27% (P > .05). None of the sealers showed a significant increase in pH (P > .05). CONCLUSIONS: Sealer Plus sealer presented physicochemical properties in accordance with American National Standards Institute/American Dental Association (2000) No. 57 and International Organization for Standardization 6876 (2012) specifications.

Chemical-physical Properties and Apatite-forming Ability of Mineral Trioxide Aggregate Flow.

INTRODUCTION: This study aimed to analyze the chemical-physical properties, including pH, volumetric change, radiopacity, and apatite-forming ability in simulated body fluid, of a new tricalcium silicate material (MTA Flow; Ultradent Products Inc, South Jordan, UT). METHODS: MTA Flow was tested in comparison with MTA Angelus (Angelus, Londrina, PR, Brazil). The pH of soaking water was tested up to 168 hours in deionized water. In the solubility test, the root-end fillings of 20 acrylic teeth were scanned twice by micro-computed tomographic imaging before and after immersion in ultrapure water for 168 hours. In addition, using an aluminum step wedge, the radiopacity of each material was evaluated as recommended by international standards. The mean gray values of the test materials were measured using ImageJ software (National Institutes of Health, Bethesda, MD). The morphologic and chemical analyses of the material surface were performed using scanning electron microscopic energy-dispersive X-ray spectroscopic analysis after 28 days in Hank's balanced salt solution (HBSS). The data were analyzed using 2-way analysis of variance with the Student-Newman-Keuls test (P < .05). RESULTS: MTA Flow showed similar alkalizing activity to that of MTA Angelus. In the solubility test, both materials presented lower values without statistical differences. Both materials showed a marked alkalinizing activity within 3 hours, which continued for 168 hours. MTA Angelus showed statistically higher radiopacity values (P < .05). All materials showed the ability to nucleate calcium phosphate on their surface after 28 days in HBSS. CONCLUSIONS: MTA Flow showed remarkable alkalinizing capability, low solubility, good radiopacity, and the ability to form calcium phosphate deposits after being soaked in simulated body fluid, showing values similar to those of MTA Angelus.

O uso do laser e seus princípios em endodontia: revisão de literatura / The use of laser and its principles in endodontics: review of literature

INTRODUÇÃO: com advento e criação do aparelho laser em 1960 por Theodore Harold Maiman e a utilização do laser na Endodontia em 1971 com Weichman várias aplicações potenciais foram criadas para a utilização dos lasers. Este estudo permite ao clínico um melhor entendimento da utilização do laser dentro da odontologia mais especificamente na área endodôntica. OBJETIVO: evidenciar o uso do equipamento laser na área endodôntica nas modalidades em: Auxílio no diagnóstico pulpar, capeamento pulpar, pulpotomia, preparo e Limpeza do canal radicular, esterilização dos canais radiculares e terapia fotodinâmica (PDT), irrigação dos canais radiculares, remoção de smear layer e cirurgia parendodontica. MÉTODO: trata-se de uma revisão de literatura estruturada. CONCLUSÃO: este estudo fornece evidências de que o equipamento laser pode ser pensado e usado como um instrumento alternativo o qual pode complementar ou substituir alguns dos tratamentos endodônticos convencionais. (AU)

Introduction: with advent and creation of the laser apparatus in 1960 by Theodore Harold Maiman and posterior use in Endodontics in 1971 with Weichman, several potential applications were created for the use of lasers. This study allows the clinician a better understanding of the use of the laser in dentistry more specifically in the endodontic area. Objective: the objective of this study is to show the use of laser equipment in the endodontic area in the following modalities: Pulp diagnosis, pulp capping, pulpotomy, preparation and root canal cleaning, sterilization of root canals and photodynamic therapy (PDT), root canal irrigation, Smear layer removal and parendodontic surgery. Method: a critical literature review. Conclusion: this study provides evidence that laser equipment can be considered and used as an alternative instrument that can complement or replace some of the conventional endodontic treatments. (AU)

Influência da umidade na penetração, resistência de união à dentina radicular bovina e tipo de falha de união de cimentos endodônticos: análise por meio de microscópio confocal de varredura a laser e teste mecânico push-out / The influence of humidity on penetration, bond strenght and bonding failure type of endodontic sealers: analysis by laser scanning microscopy and mechanical push-out test

O objetivo deste estudo foi avaliar a influência da umidade na penetração, resistência de união e tipo de falha de união de cimentos endodônticos junto às paredes de canais radicular por meio de microscopia confocal de varredura a laser e teste mecânico push-out. Foram utilizados 120 dentes bovinos unirradiculados, previamente selecionados raízes retas e com ausência de grandes achatamentos. As coroas foram removidas, com a finalidade de padronizar os espécimes em 16 mm de comprimento. A extensão de trabalho foi estabelecida 1 mm aquém do forame. Inicialmente os canais foram explorados com lima tipo K 70 e instrumentadas até a lima tipo K110 e a irrigação foi realizada com 2 mL de NaOCl a 2,5% a cada troca de instrumento. Ao final, foram aplicados 2 mL de EDTA por 3 minutos e a irrigação final foi feita com soro fisiológico. Em seguida, as raízes foram divididas, aleatoriamente, em 8 grupos de acordo com o cimento obturador. As técnicas e presença ou não de umidade (n=15): G1: AH/CLSU (cimento AH Plus/condensação lateral sem umidade); G2: AH/CLCU (cimento AH Plus/condensação lateral com umidade); G3: AH/TPSU (cimento AH Plus/termoplastificadora sem umidade); G4: AH/TPCU (cimento AH Plus/termoplastificadora com umidade); G5: FA/CLSU (cimento FillApex/condensação lateral sem umidade); G6: FA/CLCU (cimento FillApex/condensação com umidade); G7: FA/TPSU (cimento FillApex/termoplastificadora sem umidade); G8: FA/TPCU (cimento FillApex/termoplastificadora com umidade). Depois de obturados, os canais foram armazenados em umidade por 72 horas. As raízes foram seccionadas transversalmente a 2, 4 e 6 mm do forame e analisadas em microscopia confocal de varredura à laser (540 a 590 nm), para avaliação da penetração dos cimentos nos túbulos dentinários e, posteriormente, submetidos ao teste de push-out. Além disso, foram avaliados os tipos de falhas (adesiva, coesiva ou mista) por meio de estereomicroscópio em aumento de 40x. Os dados foram submetidos aos testes estatísticos de D'agostino e Pearson para a verificação de distribuição normal. Foi aplicado o teste de Kruskal ­ Wallis e Dunn para ambos os testes, com nível de significância de α 5% (p=0,05). Os resultados permitiram observar que, com relação à penetração, o cimento MTA Fillapex apresentou maiores valores que o cimento AH Plus, considerando as técnicas obturadoras. Pode­se observar maior penetração quando foi empregada a técnica da condensação lateral. Com relação à resistência de união, observou-se que o cimento AH Plus proporcionou valores superiores. A condensação lateral ativa mostrou melhores resultados quando utilizado o AH Plus. O cimento MTA Fillapex proporcionou melhores resultados quando empregada à técnica termoplastificadora. Por fim, com relação ao tipo de falha de união, os resultados permitiram deduzir que não houve diferença estatística significante entre os cimentos e técnicas utilizadas. Concluiu-se que a resistência de união e profundidade de penetração pode ser influenciada pela técnica obturadora, cimento utilizado e presença ou ausência do fator umidade. O cimento AH Plus apresentou maiores valores quanto à resistência de união, e menores valores de penetração intratubular. O cimento MTA fillapex apresentou maiores valores de penetração, e menores valores com relação à resistência de união.(AU)

The objective of this study was to evaluate the influence of humidity on penetration, bond strength and failure type of Union of endodontic sealers along root channels walls by means of laser scanning confocal microscopy and mechanical push-out test. 120 were used single root bovine teeth, previously selected roots straight and with absence of large crushed parts. The crowns were removed, with the purpose of standardizing the specimens in 16 mm in length. The extension work was established 1 mm below the foramen. Initially the channels have been explored with 70 K file and instrumented to the lima K110 type and irrigation was performed with 2 mL of NaOCl to 2.5% every exchange of instrument. At the end, 2 mL of EDTA were applied for 3 minutes and the final was made irrigation with saline. Then, the roots were randomly divided in 8 groups according to the cement plug, the techniques and the presence or not of humidity (n = 15): G1: OH/CLSU (cement AH Plus/lateral condensation without moisture); G2: OH/CLCU (cement AH Plus/lateral condensation with humidity); G3: OH/TPSU (cement AH Plus/thermoplastic obturation without moisture); G4: OH/TPCU (cement AH Plus/ thermoplastic obturation with moisture); G5: FA/CLSU (FillApex cement/lateral condensation without moisture); G6: FA/CLCU (FillApex cement/condensation with humidity); G7: FA/TPSU (FillApex/ thermoplastic obturation cement without moisture); G8: FA/TPCU (cement FillApex/ thermoplastic obturation with moisture). After it closed, the channels were stored in moisture for 72 hours. The roots were sectioned transversally 2, 4 and 6 mm from the apex and analyzed in laser scanning confocal microscopy (540 to 590 nm), to assess the penetration of cement on Dentinal tubules and, subsequently, submitted to the push-out test. In addition, we evaluated the types of failures (adhesive, cohesive or mixed) through the stereomicroscope in increase of 40 x. The data were subjected to statistical tests of D'Agostino and Pearson for verification of normal distribution. Was applied the Kruskal-Wallis and Dunn for both tests, with a significance level of α 5% (p = 0.05). The results allowed to note that, with respect to penetration, the MTA Fillapex cement presented higher values that cement AH Plus, considering the obturation techniques can-see greater penetration when was employed the lateral condensation technique. With regard to union resistance, it was observed that AH Plus cement provided higher values. The lateral condensation activates showed best results when used AH Plus. MTA Fillapex cement provided better results when employed the thermoplastic obturation. Finally, with respect to the type of failure, the results have made it possible to deduce that there was no significant statistical difference among the cements and techniques used. It was concluded that the Union resistance and penetration depth can be influenced by the obturator technique, cement used and presence or absence of the moisture factor. AH Plus cement showed highest values regarding Union resistance, and lower values of intratubular penetration. MTA fillapex cement presented greater values of penetration, and smaller values with respect to Union resistance.(AU)