ARE CALCIUM SILICATE SEALERS LESS CYTOTOXIC AND GENOTOXIC THAN EPOXY RESIN SEALERS? A SYSTEMATIC REVIEW OF IN VITRO STUDIES

Aims: This systematic review aimed to evaluate whether calcium silicate-based sealers are less cytotoxicity and genotoxicity than epoxy resin-based sealers. Materials and Methods: Systematic searches were conducted for studies published up to September 27th, 2022, without restriction for language or year of publication, in the following databases: MEDLINE/PubMed, Scopus, Web of Science and Grey Literature Report. Only in vitrostudies that evaluated the cytotoxicity or genotoxicity of calcium silicate and epoxy resin-based sealers were included. The quality assessment was performed. Results: After duplicate removal and eligibility criteria assessment, a total of thirty-four studies were included. Twenty-eight studies had a low risk of bias, and six studies had amoderate risk of bias. In general, calcium silicate-based sealers had a lower cytotoxic and genotoxic potential than epoxy-resin based sealers.Conclusions: Based on the findings from in vitrostudies, calcium silicate-based sealers are less cytotoxic andgenotoxic than epoxy resin-based sealers

POSTOPERATIVE PAIN INCIDENCE AND INTENSITY FOLLOWING ROOT CANAL OBTURATION WITH BIOCERAMIC AND OTHER SEALERS: A SYSTEMATIC REVIEW WITH META-ANALYSIS

Aims: To investigate whether bioceramicsealers induce a lower incidence and intensity of postoperative pain compared to other sealers. Materials and Methods: Six electronic databases were searched for studies published up to April 2022, following the PICOS strategy: (P) adult patients undergoing root canal treatment or retreatment; (I) root canal filling using bioceramic sealer; (C) root canal filling using other types of sealers; (O) Primary: postoperative pain incidence and/or intensity; Secondary: number of medication intake; (S) randomizedclinical trials. Risk of bias assessment was performed with the revised Cochrane risk of bias tools for randomized trials (RoB 2). Overall certainty of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. Results: Ten studies were included. Eight studies had a low risk of bias, and two had some concerns risk. Meta-analyses showed no differences regarding postoperative pain intensity and incidence between bioceramic sealers and AH Plus. Number of medication intake seemed to be associated to the preoperative diagnosis. Zinc oxide-eugenol sealer demonstrated an intense postoperative pain compared to bioceramic sealers and AH Plus. GRADE analysis showed a low certainty of evidence for all outcomes. Conclusions: There seem to be no differences between bioceramic sealers and AH Plus regarding postoperative pain intensity and incidence. Number of medication intake seem to be associated to the preoperative diagnosis. Zinc oxide-eugenol evoked a more pronounced postoperative pain.

Analysis of pH, calcium ion release, and energy dispersive spectroscopy of a bioceramic root canal dressing

Abstract This study compared the pH and calcium ion release of calcium silicate- (Bio-C Temp) and calcium hydroxide-based (Ultracal XS) medications. Intracanal remnants of both medications were also evaluated using SEM-EDS after the removal protocol. Thirty-five bovine teeth were prepared. Fifteen were filled with Bio-C Temp and 15 with Ultracal XS. Five remained without intracanal medication (control group). Five samples from each experimental time (i.e.. 24, 72, and 168 hours) were used to measure pH and calcium ions release using a digital pH meter and microplate reader, respectively. Afterward, the peaks of the chemical elements composing both medications were analyzed in SEM-EDS. One-way ANOVA and Tukey's post hoc test analyzed the pH and calcium ion release data. Student's t-test compared the medications in each experimental time. SEM-EDS described the percentage of chemical elements in the samples. Bio-C Temp and Ultracal XS showed a significant pH increase from 24 to 168 hours (p<0.05). Ultracal XS showed a higher pH value at 24 hours than Bio-C Temp (p<0.05) but were similar at 72 and 168h (p > 0.05). Calcium ion release did not depend on the experimental period (p > 0.05). Bio-C Temp showed lower calcium ions release than Ultracal XS at 24 hours (p<0.05). SEM-EDS analyses showed the remains of both medications, but the concentration of Si, Al, and W ions was present only in the calcium silicate-based medication. Bio-C Temp presented alkaline pH and a satisfactory calcium ion release over the time. The remaining of both medications were present after the protocols for paste removal.

Resumo Este estudo comparou o pH e a liberação de íons cálcio de medicações intracanais a à base de silicato de cálcio (Bio-C Temp) e à base de hidróxido de cálcio (Ultracal XS). Remanescentes de ambas as medicações também foram avaliados usando microscopia eletrônica de varredura e espectroscopia de dispersão de energia após o protocolo de remoção. Trinta e cinco dentes bovinos foram preparados. Quinze dentes foram preenchidos com Bio-C Temp e 15 com Ultracal XS. Cinco permaneceram sem medicação intracanal (grupo controle). Cinco amostras de cada tempo experimental (ou seja, 24, 72 e 168 horas) foram usadas para medir o pH e a liberação de íons de cálcio usando um medidor de pH digital e um leitor de microplacas, respectivamente. Em seguida, os picos dos elementos químicos que compõem os dois medicamentos foram analisados ​​em microscopia eletrônica de varredura e por espectroscopia de dispersão de energia. Os testes One-way ANOVA e post hoc de Tukey analisaram os dados de pH e liberação de íons cálcio. O teste t de Student comparou as medicações em cada tempo experimental. A microscopia eletrônica de varredura e a espectroscopia de dispersão de energia descreveu a porcentagem de elementos químicos nas amostras. O Bio-C Temp e o Ultracal XS mostraram um aumento significativo de pH de 24 a 168 horas (p<0,05). O Ultracal XS apresentou um valor de pH mais alto em 24 horas do que o Bio-C Temp (p<0,05), mas foi semelhante em 72 e 168h (p > 0,05). A liberação de íons cálcio não dependeu do período experimental (p> 0,05). O Bio-C Temp apresentou menor liberação de íons de cálcio do que Ultracal XS em 24 horas (p<0,05). As análises de microscopia eletrônica de varredura e espectroscopia de dispersão de energia mostraram remanescentes de ambas as medicações, mas a concentração de íons Si, Al e W estavam presentes apenas na medicação à base de silicato de cálcio. O Bio-C Temp apresentou pH alcalino e maior liberação de íons cálcio. Remanescentes de ambas as medicações estiveram presentes após os protocolos de remoção da pasta.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) - Bio-C Temp and Ultracal - after different activation protocols in teeth with simulated internal root resorption. Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05). There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05). Due to this, it can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

Aims: This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) -Bio-C Temp and Ultracal -after different activation protocols in teeth with simulated internal root resorption.Materials and methods: Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05).Results:There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05).Conclusion:It can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.

DOES THE ACTIVATION OF ROOT CANAL DRESSINGS IMPROVE THEIR FILLING QUALITY ON TEETH WITH SIMULATED INTERNAL ROOT RESORPTION?

Aims: This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) -Bio-C Temp and Ultracal -after different activation protocols in teeth with simulated internal root resorption.Materials and methods: Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P > 0.05).Results:There was no difference between activation protocols (P > 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P < 0.05), except for Easy Clean (P > 0.05).Conclusion:It can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption

Addition of MTA in a salicylate-based resin root canal sealer to retrograde root-end filling

Aim To evaluate the flow, pH and calcium release of white MTA (WMTA), salicylate-based resin root canal sealer (Sealapex; SEAL) and SEAL containing 10 (SE10) or 20% (SE20) (w/w) of MTA. Methodology Flow test was realized according to ISO 6876 specification. The sealers samples (n= 10) were placed in polyethylene tubes and immersed in deionized water. After 24 hours and 7, 14, and 28 days, the water pH was determined with a pH meter, and calcium release was assessed by atomic absorption spectrophotometry. Results SEAL and WMTA showed respectively the highest and lowest flow rate when compared with the other materials (P<0.05). SE20 showed the highest pH value only in 24h and 7 days periods (p<0.05). In 14- and 28-days periods, SEAL showed the lowest pH value (p<0.05), but there are no differences between other groups (p>0.05). In all periods, WMTA and SEAL respectively showed the highest and lowest calcium release (p<0.05). Conclusions SE20 proves to be an association with better flow and handling than WMTA, with satisfactory potential for alkalinization and calcium release.

Does the ultrasonic activation of calcium silicate-based sealers affect their physicochemical properties?

Abstract This study aimed to evaluate the influence of ultrasonic activation (UA) on the physicochemical properties of hydraulic calcium silicate-based sealers. Nine experimental conditions were created based on the hydraulic calcium silicate-based sealers (Bio-C Sealer, Sealer Plus BC and Bio Root RCS) and the ultrasonic activation (no activation [NA], 10 seconds, and 20 seconds). Then the experimental groups were BC-NA, BC-10, BC-20, SPBC-NA, SPBC-10, SPBC-20, BR-NA, BR-10, and BR-20. Activation was performed with an ultrasonic insert 20/.01. The mold for the physicochemical analysis was filled and evaluated according to the ANSI/ADA specification nº. 57: initial and final setting time, flow, radiopacity and solubility. Tests were also performed to evaluate pH and calcium ion release with experimental periods of 1, 24, 72, and 168 hours with a pH meter and colorimetric spectrophotometer. Data were analyzed by one-way analysis of variance and post-hoc Tukey tests. The significance level was set at 5%. The time of UA progressively delayed the initial setting time for all hydraulic calcium silicate-based sealers (p < 0.05). Twenty seconds of UA increased the mean flow values of Sealer Plus BC and Bio-C Sealer compared to NA (p < 0.05). UA did not influence the radiopacity and solubility of the tested sealers (p > 0.05). UA for 20 seconds enhanced the pH levels and the calcium ion release of Sealer Plus BC and Bio-C Sealer at 168h (p < 0.05). UA for twenty seconds interferes with some physicochemical properties of hydraulic calcium silicate-based sealers.

Resumo Este estudo teve como objetivo avaliar a influência da ativação ultrassônica nas propriedades físico-químicas de cimentos de silicato de cálcio. Nove condições experimentais foram criadas com base nos cimentos de silicato de cálcio (Bio-C Sealer, Sealer Plus BC e Bio Root RCS) e na ativação ultrassônica (sem ativação [SA], 10 segundos e 20 segundos). Os grupos experimentais foram BC-SA, BC-10, BC-20, SPBC-SA, SPBC-10, SPBC-20, BR-SA, BR-10 e BR-20. A ativação foi realizada com um inserto ultrassônico 20/.01. O molde para a análise físico-química foi preenchido e avaliado de acordo com a especificação ANSI/ADA nº. 57: tempo de presa inicial e final, escoamento, radiopacidade e solubilidade. Também foram realizados testes para avaliação de pH e liberação de íons cálcio com períodos experimentais de 1, 24, 72 e 168 horas com pHmetro e espectrofotômetro colorimétrico. Os dados foram analisados por análise de variância one-way e testes post-hoc de Tukey. O nível de significância foi estabelecido em 5%. O tempo de AU aumentou progressivamente o tempo de presa inicial para todos os cimentos de silicato de cálcio (p < 0,05). Vinte segundos de AU aumentaram os valores médios de escoamento de Sealer Plus BC e Bio-C Sealer em comparação com SA (P < 0,05). A AU não influenciou a radiopacidade e a solubilidade dos cimentos testados (P > 0,05). AU por 20 segundos aumentou os níveis de pH e a liberação de íons cálcio de Sealer Plus BC e Bio-C Sealer em 168h (P < 0,05). AU por vinte segundos interfere em algumas propriedades físico-químicas dos cimentos de silicato de cálcio.

Effect of bioceramic root canal sealers on the bond strength of fiber posts cemented with resin cements

Abstract This study aimed to evaluate the influence of calcium silicate-based sealers on the bond strength of fiber posts using conventional and self-adhesive resin cement. Sixty single-rooted teeth were selected. The canals were prepared with a reciprocating instrument 40.06. The roots were randomly distributed in six groups (n = 10) according to the strategies for root canal filling and fiber posts cementation: AH Plus/RelyX ARC; AH Plus/RelyX U200; Bio C Sealer/RelyX ARC; Bio C Sealer/RealyX U200; Sealer Plus BC/RelyX ARC; and Sealer Plus BC/RelyX U200. The roots were transversally sectioned, and one slice per post-third was obtained. The push-out test was performed at a crosshead speed of 1mm/min. The failure patterns were described after assessment with a stereomicroscope with a 10× magnification. Bond strength was calculated and analyzed using the ANOVA and Tukey test. AH Plus did not influence the bond strength of fiber posts cemented with conventional (RelyX ARC) or with self-adhesive resin cement (RelyX U200). The lowest bond strength values were obtained when calcium silicate-based sealers were associated with conventional resin cement (Bio C Sealer/RelyX ARC and Sealer Plus BC/RelyX ARC). Except for Sealer Plus BC/RelyX ARC, all groups presented lower bond strength at the apical portion compared to the cervical portion of the post. Adhesive failures between cement and post and cement and dentin were predominant (55.3%). Calcium silicate-based sealers decreased the bond strength of fiber posts cemented with conventional resin cement.

Resumo Este estudo teve como objetivo avaliar a influência de cimentos à base de silicato de cálcio na resistência de união de pinos de fibra utilizando cimentos resinosos convencionais e autoadesivos. Sessenta dentes humanos monorradiculares foram selecionados. Os canais foram preparados um instrumento reciprocante 40.06. As raízes foram distribuídas aleatoriamente em seis grupos (n = 10) de acordo com as estratégias de obturação do canal e cimentação dos pinos de fibra: AH Plus/RelyX ARC; AH Plus/RelyX U200; Bio C Sealer/RelyX ARC; Bio C Sealer/RealyX U200; Sealer Plus BC/RelyX ARC; e Sealer Plus BC/RelyX U200. As raízes foram seccionadas transversalmente e foi obtido um espécime por terço. O teste de push-out foi realizado em uma velocidade de 1mm/min. Os padrões de falha foram descritos após avaliação em estereomicroscópio com aumento de 10×. A resistência de união foi calculada e analisada por ANOVA e teste de Tukey. AH Plus não influenciou na resistência de união dos pinos de fibra cimentados com cimento resinoso convencional (RelyX ARC) ou autoadesivo (RelyX U200) (p > 0,05). Os menores valores de resistência de união foram obtidos quando os cimentos à base de silicato de cálcio foram associados ao cimento resinoso convencional (Bio C Sealer/RelyX ARC e Sealer Plus BC/RelyX ARC) (p < 0,05). Com exceção do Sealer Plus BC/RelyX ARC, todos os grupos apresentaram menor resistência de união na porção apical em comparação com a porção cervical do pino (p < 0,05). Falhas adesivas entre cimento e pino e cimento e dentina foram predominantes (55,3%). Cimentos a base de silicato de cálcio diminuíram a resistência de união de pinos de fibra cimentados com cimento resinoso convencional.

Effects of dentinary contamination by endodontic irrigants on bonding strength of adhesive systems

This study aimed to evaluate if 2.5% sodium hypochlorite compromises the adhesion of bonding materials. The factors in the study were the irrigation solutions in two levels: 2.5% sodium hypochlorite and saline solution; and the adhesive systems used in three levels: three-step adhesive, universal adhesive, and two-step self-etch adhesive systems. The answer variable used was the microshear bond strength obtained through a universal testing machine and fracture mode. Six groups were obtained (n=10) : Etch-and-rinse/Saline (saline solution + 3-step adhesive system - Scotchbond Multipurpose, 3M ESPE); Universal/saline (saline solution + universal adhesive system ­ Prime&Bond,); Self-etch/saline (saline solution + 2-step self-etch adhesive systems - Clearfil SE Bond); Etch-and-rinse/Hypo (sodium hypochlorite 2,5% + 3-step adhesive system - Scotchbond Multiuso); Universal/Hypo (sodium hypochlorite 2,5% + universal adhesive system ­ Prime&Bond); Self-etch/Hypo (sodium hypochlorite 2,5% + 2-step self-etch adhesive system - Clearfil Se Bond). The specimens were obtained from 60 healthy bovine incisors. The crowns were separated from the roots, and the regularization of the buccal surface was performed. The groups received saline solution and 2.5% sodium hypochlorite for 30 minutes, respectively. A matrix of 1mm and 3mm oh height was stabilized by Scotch tape to obtain the resin sticks. Afterward, the bond strength test was performed in a universal testing machine at 1mm/min speed. The data were analyzed with normality Shapiro-Wilk, two-way ANOVA, and Tukey's tests (p<0.001). Etch-and-rinse and Self-etch adhesives presented the highest bond strength values after irrigation with saline solution and 2.5% sodium hypochlorite, respectively (P < 0.01). The irrigation with 2.5% sodium hypochlorite decreased the bond strength values of Etch-and-rinse and Universal (P < 0.01). On the other hand, 2.5% sodium hypochlorite improved the bond strength values of Self-etch (P < 0.01). In conclusion, 2.5% sodium hypochlorite negatively impacted the bond strength of Etch-and-rinse and Universal but improved the adhesion of Self-etch.

Evaluation of the dentinal tubule penetration of an endodontic bioceramic sealer after three final irrigation protocols

Introduction: This study aimed to evaluate the dentinal tubule penetration of an endodontic bioceramic sealer, Sealer Plus BC, after three final irrigation protocols. Methods: Thirty distobuccal roots of maxillary molars were selected. Root canal preparation was performed up to an #40.06 instrument (X1 Blue) under 2.5% sodium hypochlorite irrigation. Specimens were randomly divided into three groups (n=10), according to the final irrigation protocol: G-NaOCl (2.5% sodium hypochlorite + PUI), G-SS (0.9% saline solution + PUI) and G-H20 (Deionized water + PUI). After final irrigation protocols, all specimens were irrigated with phosphate buffer solution. Root canal obturation was performed using the single cone technique and Sealer Plus BC, stained with a specific fluorophore. Specimens were transversely sectioned and each root third was evaluated in a confocal scanning laser microscopy. Images obtained were analyzed for sealer penetration in the dentinal tubules. Results: Dentinal tubule penetration of Sealer Plus BC was not observed in any root third, regardless of the final irrigation protocol investigated. Conclusions: Sealer Plus BC dentinal tubule penetration was not observed after none of the protocols tested. Dentinal tubule penetrability of Sealer Plus BC may be related to other factors rather than the final irrigation protocol.

Effect of nickel-titanium alloys on root canal preparation and on mechanical properties of rotary instruments

Abstract The aim of this study was to evaluate the quality of curved root canal preparation, torsional fatigue, and cyclic fatigue of rotary systems manufactured with different NiTi alloys. Ninety single-rooted canals with curvatures of 15° to 30o were scanned and divided into three groups according to the rotary system used: BT-Race (BTR) - 10.06, 35.00, 35.04; SequenceRotaryFile (SRF) - 15.04, 25.06, 35.04; and ProDesignLogic (PDL) - 25.01, 25.06, 35.05. Each system was used on three specimens. The teeth were prepared, scanned, and analyzed to assess increase in volume, transportation, and centering ability of the root canal. Torsional fatigue of glide path instruments (BTR 10.06, SRF 15.04 and PDL 25.01) and cyclic fatigue of the finishing instrument (BTR 35.04, SRF 35.04 and PDL 35.05) were obtained by analyzing completely new instruments (n = 10) and instruments after they had been used three times (n = 10). After the torsional and cyclic fatigue tests, the fractured surface of the new and used instruments were examined by scanning electron microscopy. Increase in volume, canal transportation, and centering ability showed no significant differences among the groups (p > 0.05). The torsional test showed that SRF 15.04 produced the highest torque values for both new and used instruments, followed by PDL 25.01 and BTR 10.06 (p < 0.05). PDL 25.01, both new and used, exhibited higher values of angular deflection followed by SRF 15.04 and BTR 10.06 (p < 0.05). As regards cyclic fatigue, use of PDL 35.05, both new and used, required a longer time and larger number of cycles than did SRF 35.04 and BTR 35.04 (p < 0.05). Clinical use affected the torsional fatigue of BTR; however, cyclic fatigue was not significantly affected (p < 0.05). All rotary systems were able to prepare the curved canals satisfactorily and were used safely on the three specimens. Relative to torsional fatigue, SRF 15.04 exhibited a higher torque, and PDL 25.01, higher angular deflection. BTR 10.06 was the most affected by clinical use. PDL 35.05 showed greater resistance to cyclic fatigue.

Successful revascularization procedure in an immature permanent necrotic second lower molar: a case report with 4. 5- years follow- up

Background: Infection control is mandatory for revascularization procedures, enabling to eliminate patient's clinical symptoms and signs. Despite presenting a complex morphology when compared to anterior teeth, if a strict disinfection protocol is adopted and the revascularization procedure's biological principles are followed, the therapy can be successful in molar teeth. Methods: This case report aims to present a clinical case of successful revascularization in an immature permanent necrotic second lower molar. Clinical decisions and explanations regarding possible mechanisms related to the treatment's success in a tooth with complex morphology are discussed. Results: Revascularization procedures were performed on a 12-year-old male patient diagnosed with symptomatic periapical periodontitis in a tooth 37. The case highlights the need for infection control and biological principles that surrounds the success of this therapy. Follow-up times presented in this case were six months, 1, 2, 4 and 4.5-years, respectively. Continued root development was observed, and the tooth remains intact and without symptoms. Conclusion: The association of infection control and the biological principles of revascularization procedures allow the maintenance and continuation of tooth development, even when these present complex morphologies.

Evaluation of the impact of pain from dental urgencies on the patients' oral health- related quality of life: a cross- sectional study

Background. This cross-sectional study aimed to evaluate the impact of pain from dental urgencies on the oral health-related quality of life (OHRQoL). Methods. A sample of sixty-eight patients seeking urgent attention to a primary health unit were included. Clinical diagnosis and sociodemographic data were assessed, dental pain measured by visual analog scale (VAS) and numerical pain rating scale (NPRS). The Oral Health Impact Profile-14 (OHIP-14) instrument was used to measure the OHRQoL. Associations were analyzed using the Student t-test, except for types of urgencies, that were evaluated with one-way analysis of variance (ANOVA) test. Results. The most prevalent urgency type was of endodontic origin (81%). There was no difference between pain and other variables. The type of tooth showed significant differences in OHIP-14 scores. Conclusion. Dental urgencies were associated with a high level of pain and impacted negatively on the patients' OHRQoL. The type of tooth had a positive association the OHRQoL measures.

Taxa de publicação de resumos da área de Endodontia apresentados na Sociedade Brasileira de Pesquisa Odontológica entre 2013 e 2016 / Full-length publication rates of endodontic abstracts presented at the Brazilian Society of Oral Research meetings between 2013 and 2016

O conceito de Odontologia baseada em evidências requer a produção e publicação de pesquisas de alta qualidade em periódicos internacionais criteriosos. Objetivo: O presente estudo teve como objetivo avaliar as taxas de publicação de resumos endodônticos apresentados na reunião da SBPqO nos anos de 2013, 2014, 2015 e 2016. Material e Métodos: O fator de impacto e a classificação Qualis dos periódicos, e o tempo decorrido entre o congresso e a publicação completa também foram avaliados. Em seguida, foram classificados em seis categorias: pesquisa básica endodôntica, revisão de temas endodônticos, estudos clínicos, ensaios clínicos randomizados, pesquisa básica tecnológica ou relatos de caso. Uma pesquisa em bancos de dados eletrônicos usando o mecanismo Medline (PubMed) foi realizada de janeiro de 2018 a julho de 2018, para identificar publicações escritas em inglês com texto completo dos resumos endodônticos previamente selecionados. A identificação da publicação em texto completo dos resumos foi inicialmente realizada utilizando o sobre- nome do primeiro autor e as principais palavras-chave do título do resumo. Após a verificação do artigo em texto completo, informações adicionais foram registradas, tais como: tempo decorrido até a publicação; nome, fator de impacto e classificação Qualis da revista; e o tipo de estudo. Resultados: Após a leitura do conteúdo da reunião, 1.238 resumos (10,2%) foram considerados de interesse endodôntico e, em seguida, foi realizada uma busca eletrônica no banco de dados. Conclusão: Um grande número de resumos endodônticos não foi publicado como um manuscrito completo. Estudos clínicos e ensaios clínicos randomizados representaram uma pequena parte das publicações (AU).

Evidence-based dentistry consists in the clinical application of concepts based on researches pub- lished as scientific papers in indexed periodicals. Objective: This study aimed to evaluate the publication rates of endodontic abstracts presented in the meeting of SBPqO in the years of 2013, 2014, 2015 and 2016. Materials and Methods: Endodontic abstracts presented between 2013 and 2016 were included. Then, they were classified into six categories: endodontic basic research, review endodontic topics, clinical studies, randomized clinical trials, technological basic research or case reports. An electronic database search using the Medline (PubMed) engine was performed from January 2018 to July 2018 to identify full-text English-written publications of the endodontic abstracts previously selected. The identification of full-text publication of the abstracts was initially performed using the first authors last name and the main keywords from the title of the abstract. Following full-text article verification, additional information was recorded such as: elapsed time until publication; name, impact factor and Qualis classification of the journal; and type of study. Results: After reading the content of the meeting, 1,238 abstracts (10.2%) were considered to be of endodontic interest, and then an electronic database search was performed. Conclusion: A large number of endodontic abstracts were not published as a full-length manuscript. Clinical studies and randomized clinical trials represented the small part of the publications (AU).

Avaliação da resistência à fadiga cíclica e torcional de quatro instrumentos rotatórios de NiTi com secções transversais semelhantes e diferentes tratamentos térmicos / Cyclic and torsional fatigue resistance of four rotary NiTi instruments with similar cross-sectional design and different thermal treatments

Objetivo: O objetivo do presente trabalho foi avaliar a resistência à fadiga cíclica e torcional de instrumentos rotatórios de níquel-titânio com secções transversais semelhantes e confeccionados com diferentes tipos de tratamentos térmicos: Hyflex CM (HCM 25/.06), Vortex Blue (VB 25/.06), Sequence Rotary File (SRF 25/.06) e EdgeSequel (EDF 25/.06) (n=20). Métodos: O teste de fadiga cíclica avaliou o tempo e o número de ciclos para a fratura (NCF) dos instrumentos em canal artificial com 60° de curvatura e 5mm de raio (n=10). O teste de torção avaliou o torque máximo e a deflexão angular para a fratura dos 3mm da ponta dos instrumentos (n=10). Após o teste de torção e de fadiga cíclica, os instrumentos foram avaliados em microscopia eletrônica de varredura (MEV) (n=10). Os dados foram analisados empregando-se os testes ANOVA e de Tukey, sendo selecionado um nível de significância de 5%. Resultados: HCM apresentou o maior tempo e NCF entre todos os instrumentos avaliados (p<0,05). O SRF apresentou um tempo semelhante (p>0,05) e menor NCF (p<0,05) do que o VB. Em relação ao teste torcional, o HCM apresentou menor valor de torque e maior deflexão angular entre os grupos avaliados (p<0,05). Não houve diferenças significativas entre VB, SRF e EDF em relação à deflexão angular (p>0,05). Conclusão: O HCM apresentou maior resistência à fadiga cíclica e deflexão angular. Entretanto, o VB apresentou maior resistência torcional para a fratura (AU).

Objective: The aim of this study was to evaluate the cyclic and torsional fatigue resistance of Nickel-Titanium rotary instruments with similar cross-sectional design and manufactured by different thermal treatments: Hyflex CM (HCM 25/.06) Vortex Blue (VB 25/.06), Sequence Rotary File (SRF 25/.06) and EdgeSequel (EDF 25/.06) (n=20). Material and Methods: Cyclic fatigue test evaluated the time and number of cycles to failure (NCF) in an artificial stainless steel canal with 60° and 5-mm radius of curvature (n=10). The torsional test (ISO 3630-1) evaluated he maximum torque and distortion angle to failure at 3 mm from the tip (n=10). After the torsional and cyclic fatigue test the instruments were evaluated by scanning electron microscope (SEM). Data were analyzed using one-way ANOVA and Tukey tests, and the level of significance was set at 5%. Results: The HCM presented the longest time and highest NCF to fatigue than all the groups (P<0.05). The SRF presented similar time (P>0.05) and lower NCF (P<0.05) to fatigue than VB. Regarding to the torsional test, HCM presented the lowest torque load and the highest distortion angle of all the groups (P<0.05). No significant difference was found among VB, SRF and EDF regarding the distortion angle (P>0.05). Conclusion: The HCM presented the highest cyclic fatigue resistance and distortion angle to failure. However, the VB showed higher torsional load to failure. (AU).

Evaluation of type of kinematics on glide path procedures and torsional fatigue resistance after preparation of moderately curved canals

Abstract: Sixty moderately curved canals of mandibular molars classified as Vertucci's type IV canal configuration were selected by micro-CT 1174. The teeth were divided into two groups according to the kinematics used, whether reciprocating or rotary motion (n=30, totaling 60 mesial root canals). The instruments used to perform the glide path procedures had identical features (0.15 mm of tip size, 0.04 mm/mm taper, thermal treatment, and square cross-section), but differed in the direction of the cutting blade. The duration of the procedure and the absolute and percentage frequency of the instruments to reach the full working length were recorded. The torsional test (3630-1; 1992) was performed on both used and unused instruments, to evaluate a possible reduction in the torsional resistance when using the glide path procedure. Statistical analysis was performed using the unpaired t-test and the chi-square test, and the level of significance was set at 5%. The type of kinematics used affected the duration of glide path procedures, and the reciprocating motion seemed to induce less torsional stress during glide path procedures.

Eficácia de três protocolos de irrigação final para remoção de raspas dentinárias e material obturador em irregularidades simuladas / Effectiveness of three final irrigation protocols for debris and filling removal from simulated irregularities

Objetivos: Avaliar três protocolos de irrigação final para remoção de detritos e material obturador de istmos simulados. Métodos: Setenta e oito pré-molares foram preparados com o sistema WaveOne Gold 45.05. Os dentes foram seccionados longitudinalmente e um istmo padronizado foi confeccionado no terço apical. Seis raízes foram utilizadas como controle negativo. Os espécimes foram randomizados em dois grupos principais (n=36). Trinta e seis raízes tiveram o istmo preenchido com detritos e as outras trinta e seis raízes foram obturadas com guta-percha e cimento endodôntico, por meio da técnica híbrida de Tagger. Cada grupo foi dividido em três subgrupos (n=12), de acordo com o protocolo de irrigação final: Easy Clean; irrigação ultrassônica passiva (PUI); e XP Clean. A ativação do NaOCl 2,5% pelo Easy Clean foi realizada em três ciclos de vinte segundos; e pelo XP Clean, por um minuto em movimento reciprocante e contínuo, respectivamente. No grupo PUI, o irrigante foi ativado em três períodos de vinte segundos. Resultados: Não foi encontrada associação entre os escores de remoção de detritos e os protocolos de irrigação (p=0,165). Foi observada associação entre os escores de remoção do material obturador e os protocolos de irrigação final (p<0,05). Conclusões: Os protocolos de irrigação final foram efetivos para a remoção de detritos, mas não para remoção de material obturador de istmos no terço apical (AU).

This study aimed to assess three final irrigation protocols on debris and filling removal from simulated irregularities. Methods: Seventy-eight mandibular premolars were prepared with WaveOne Gold system 45.05, splitted longitudinally, and a standardized groove was performed in the apical portion of the canals. Six roots served as negative control. The roots were randomly divided into two main groups (n = 36). The grooves were filled with dentin debris in thirty six roots. The others thirty-six were filled with gutta-percha and endodontic sealer using Tagger hybrid technique. Each main group was then divided into three groups (n = 12) according to the final irrigation protocol: Easy Clean, passive ultrasonic irrigation (PUI), and XP Clean. In Easy Clean 2.5% NaOCl activation was performed for 3 cycles of 20 seconds and XP Clean for one minute under reciprocating and continuous rotary motion and continuous rotary motion, respectively. In the PUI group, the irrigant was activated in three periods of 20 seconds. Results: No association was found among the scores of debris removal and the irrigation protocols (p = .165). An association was observed among the filling material removal scores and irrigation protocols (p< .05). Conclusion: Easy Clean, PUI and XP Clean were effective for dentin debris removal, but did not for filling material from artificial grooves in the apical third (AU).

Ultrasonic tips as an auxiliary method for the instrumentation of oval-shaped root canals

Abstract To evaluate the influence of novel ultrasonic tips as an auxiliary method for the rotary preparation of flattened/oval-shaped canals. Forty-five mandibular incisors were selected and divided into one of three experimental groups (n = 15): Group PFCP - ProDesign Logic 25/.05 + Flatsonic + Clearsonic + Prodesign Logic 40/.01; Group FCP - Flatsonic + Clearsonic + ProDesign Logic 40/.01; and Group PP - Prodesign Logic 25/.05 + Prodesign Logic 40/.05. The teeth were scanned preoperatively and postoperatively using microcomputed tomography. The percentage values for increase in volume, non-instrumented surface area, dentin removal, degree of canal transportation, and centering ratio between the experimental groups were examined. Data were analyzed using the non-parametric Kruskal-Wallis and Dunn's tests (p < 0.05). Group PFCP showed the greatest volume increase in the total portion of the root canal and the lowest percentage of non-instrumented surface area. Regarding the degree of transportation in the buccolingual direction, statistically significant differences between groups PFCP and PP were observed at the coronal third of the canal. In the mesiodistal direction, no statistically significant differences were observed at the coronal, middle, and apical thirds. As for the centering ratio, statistically significant differences were found in the buccolingual direction. In the mesiodistal direction, no statistically significant differences were observed at the coronal, middle, and apical thirds. The use of novel ultrasonic tips combined with rotary instruments in group PFCP provided a significant increase in volume and reduced the percentage of non-instrumented areas during the preparation of flattened/oval-shaped canals.

Evaluation of physicochemical properties of new calcium silicate-based sealer

Abstract This study aimed to evaluate the physicochemical properties of a calcium silicate-based sealer (Sealer Plus BC; MK Life, Porto Alegre, Brazil) compared with an epoxy-resin sealer (AH Plus; Dentsply DeTrey GmbH, Konstanz, Germany). Initial and final setting time was assessed based on ISO 6876:2012 and ASTM C266:03. Calcium ion release and pH were evaluated by filling polyethylene tubes with sealers and then immersing them in 10 mL of deionized water. Following experimental periods of 1, 24, 72 and 168 hours, the samples were measured regarding pH and calcium ion release with a pH meter and a colorimetric spectrophotometer, respectively. The flow was examined based on ISO 6876:2012. Rings of 10 mm in diameter with 1 mm thickness were prepared to analyze the radiopacity (ISO 6876:2012 and ADA n.57) and solubility (ISO 6876:2012). The data were analyzed by variance analysis, Student-T and Tukey tests (p<0.05). The calcium ion release and pH values were significantly higher for the Sealer Plus BC compared with the AH Plus (p<0.05). Lower setting time, flow and radiopacity were observed for the bioceramic sealer than for AH Plus (p<0.05). Sealer Plus BC exhibited higher solubility compared with AH Plus (p<0.05). Sealer Plus BC showed physicochemical properties as setting time, pH, calcium release, flow, and radiopacity following the required standards, but higher solubility than the minimum values required by ISO 6876:2012.

Resumo Este estudo teve por objetivo avaliar as propriedades físico-químicas de um cimento à base de silicato de cálcio (Sealer Plus BC MK Life, Porto Alegre, Brasil) e compará-las a um cimento à base de resina epóxica (AH Plus, Dentsply DeTrey GmbH, Konstanz, Alemanha). Tempo de presa inicial e final foram avaliados com base na ISO 6876:2012 e ASTM C266:03. Liberação de íons cálcio e pH foram avaliados após o preenchimento de tubos de polietileno com os cimentos e imersão em 10 mL de água deionizada. Após os tempos experimentais de 1,24,72 e 168 horas, os valores de pH e liberação de íons cálcio foram mensurados utilizando um medidor de pH e um espectofotômetro colorimétrico, respectivamente. Escoamento foi avaliado com base na ISO 6876:2012. Moldes de 10 mm de diâmetro e 1 mm de espessura foram preparados para análise de radiopacidade (ISO 6876:2012 e ADA n.57), solubilidade (ISO 6876:2012). Os dados foram analisados por análise de variância, teste T de Student e teste de Tukey (p<0,05). A liberação de íons cálcio e os valores de pH foram significativamente maiores para o Sealer Plus BC em comparação com o AH Plus (p<0,05). Menores valores de tempo de presa, escoamento e radiopacidade foram observados para o cimento biocerâmico quando comparados com o AH Plus (p<0,05). Sealer Plus BC apresentou propriedades físico-químicas de tempo de presa, pH, liberação de íons cálcio, escoamento, radiopacidade de acordo com as normas exigidas, porém maior solubilidade que aquelas previstas pela ISO 6876:2012.