Prevalence and reasons for referrals to the Endodontics Specialty Clinic at the Piracicaba Dental School

Abstract Dental referrals to the Endodontics Specialty Clinic (ESC) are routine owing to the complexity of endodontic treatments. To obtain a better prognosis for treatment, students/dentists must perceive their technical limits. This study sought to investigate the referrals of patients to the ESC from different clinics of the Piracicaba Dental School, State University of Campinas - SP, Brazil, and check: a) the demographic profile of patients and the most commonly affected tooth; b) the clinic with the largest number of referrals; c) the reasons for referrals; d) the complexity of the cases; e) and the difficulty in assessing the referred cases based on the classification provided by the American Association of Endodontists (AAE) and Souza-Filho. The study sample consisted of patients' electronic dental referral records from February 2015 to June 2019. A total of 1,707 patients were referred to the ESC during the study period, and 62.4% were female. Lower molars were the most frequently involved teeth (34.8%), and 60.7% of the cases were referred due to the presence of root curvature. The AAE classification showed prevalence of highly difficult cases (71.3%), whereas Souza-Filho classification demonstrated a high rate of class III cases (85.8%). This study highlights the difficulties encountered by undergraduate students before or during endodontic treatments, reinforcing the need for clear criteria for selecting cases appropriate for each education level, thus improving endodontic treatment prognosis.

Influence of working length and anatomical complexities on the apical root canal filling: a nano-CT study

Abstract The present study aimed to compare the filled volume by gutta-percha and sealer in the apical region of the main canal and ramifications, after instrumentation at two different working lengths using nano-computed tomography (nano-CT). Twenty-two premolars with apical ramifications were selected after micro-computed tomography evaluation and were randomly divided into groups for further endodontic instrumentation at two different working lengths: G1 - Root canals shaped 1 mm short of the apical foramen (n=11), and G2 - Root canals shaped at the apical foramen (n=11). After completing root treatment, nano-CT images were acquired, and the filled volume by gutta-percha and sealer in the main canal apical 0-4 mm and 0-1 mm ranges, and apical ramifications were objectively measured by an operator specialized in both radiology and endodontics, blinded for both groups. The Mann-Whitney test was applied to compare both groups regarding the filling of the main canal apical ranges and apical ramifications with a significance level of 5% (α ≤ 0.05). It was observed that root canals shaped at the apical foramen had a larger volume of the main canal filled than root canals shaped 1 mm short of the apical foramen, at both apical ranges (0-4 and 0-1 mm) (p<0.05). Regarding the filling of the apical ramifications, there was no significant difference between groups (p>0.05). In conclusion, the root canals shaped at apical foramen exhibited increased filling volume of the main canal in the apical region. However, neither of both working lengths influenced filling of the apical ramifications.

Resumo O presente estudo teve como objetivo comparar o volume preenchido por guta-percha e cimento na região apical do canal principal e ramificações, após instrumentação em dois comprimentos de trabalho diferentes, por meio de nano tomografia computadorizada (nano-TC). Vinte e dois pré-molares com ramificações apicais foram selecionados após avaliação por micro-tomografia computadorizada e foram divididos aleatoriamente em grupos para posterior instrumentação endodôntica em dois comprimentos de trabalho diferentes: G1 - Canais radiculares instrumentados 1 mm aquém do forame apical (n = 11) e G2 - Canais radiculares instrumentados até o forame apical (n = 11). Após a obturação dos canais radiculares, imagens de nano-CT foram adquiridas, e o volume preenchido por guta-percha e cimento nas faixas apicais de 0-4 mm e 0-1 mm do canal principal, e ramificações apicais, foram avaliadas objetivamente por um especialista em radiologia e endodontia, cego para ambos os grupos. O teste de Mann-Whitney foi aplicado para comparar os dois grupos quanto ao preenchimento das faixas apicais do canal principal e ramificações com nível de significância de 5% (α ≤ 0,05). Observou-se que canais radiculares instrumentados até o forame apical apresentaram maior volume do canal principal preenchido do que canais radiculares instrumentados 1 mm aquém do forame apical, em ambas as faixas apicais (0-4 e 0-1 mm) (p <0,05) Em relação ao preenchimento das ramificações apicais, não houve diferença significativa entre os grupos (p> 0,05). Em conclusão, os canais radiculares instrumentados até o forame apical mostraram um maior volume de preenchimento na região apical do canal principal. No entanto, os dois diferentes comprimentos de trabalho não influenciaram o preenchimento das ramificações apicais.

Investigation of a modified hydraulic calcium silicate-based material - Bio-C Pulpo

Abstract This study evaluated the physicochemical, biological, and antimicrobial properties of a new hydraulic calcium silicate-based modified material, and compared it with MTA Repair HP and MTA Angelus. The materials were assessed regarding color luminosity (L), color change, radiopacity, setting time, and ISO 6876:2012 linear flow. Volumetric filling and volume change were evaluated using microcomputed-tomography (µCT). Chemical characterization after 28 days in Hank's Balanced Salt Solution (HBSS) and pH analysis were also assessed. Biological characterization of cytotoxicity and microbiological assessment were also undertaken. Shapiro-Wilk, ANOVA, Levene and post hoc analyses with Bonferroni correction were performed, adopting a 5% significance level (p <0.05). Bio-C Pulpo exhibited the highest L values after 90 days. All tested materials demonstrated color change during the analyses, and had radiopacity above 5 mm Al. MTA Repair HP set faster than Bio-C Pulpo, whereas the latter had the highest linear flow. MTA Repair HP had the highest volumetric filling in µCT analysis. Bio-C Pulpo showed the highest alkalinity during all tested periods, and the highest volumetric loss (above 9%), in comparison with MTA Repair HP and MTA Angelus. Bio-C Pulpo did not form calcium hydroxide after hydration. MTA Repair HP demonstrated the highest cytocompatibility, and Bio-C Pulpo, the highest cytotoxicity. No inhibition halos were observed for any material, and similar higher turbidity values were seen after direct contact. Composition additives used in Bio-C Pulpo modified its properties, and both the absence of calcium hydroxide deposition after hydration, and the related cytotoxicity of this material are of particular concern.

Influência da ativação ultrassônica e veículo no pH dentinário em dentes com reabsorção radicular externa simulada reparados com MTA / Influence of ultrasonic activation and mixing vehicle on dentinal pH in simulated external root resorptions repaired with MTA

Avaliar o efeito da ativação ultrassônica e do veículo do MTA no pH dentinário em dentes com reabsorção radicular externa simulada. Métodos: Uma cavidade foi preparada na superfície radicular de 46 dentes bovinos, as quais foram seladas com MTA preparado com 100% de água destilada (DW) ou com 80% DW e 20% de propilenoglicol (PG). Os dentes foram divididos em quatro grupos (n = 10), de acordo com o veículo e o protocolo de ativação ultrassônica utilizado durante a inserção do material (ativação ou sem ativação). O grupo controle (n = 6) foi deixado sem selamento. O pH foi mensurado após 15, 30 e 60 dias de imersão. Resultados: A ativação com ultrassom não alterou significativamente o pH (p>0,05). Os cimentos manipulados utilizando DW + PG apresentaram maior pH aos 15 dias, em relação ao MTA manipulado com DW (p<0,05). Conclusão: A associação de 80% de água destilada com 20% de propilenoglicol aumentou o pH dentinário, o que é positivo para o reparo de reabsorções radiculares (AU).

The aim of this study was to evaluate the effect of ultrasonic activation and MTA vehicle on dentinal pH in simulated external root resorptions. So, a cavity was prepared in the root of forty-six bovine teeth. They were filled with MTA mixed with 100% distilled water (DW) or MTA mixed with 80% DW and 20% propylene glycol (PG). Teeth were divided into four groups (n = 10), according to the vehicle (DW or PG) and ultrasonic protocol used for material insertion (activated or not). Control group (n = 6) was unfilled. The pH was assessed after 15, 30 and 60 days of immersion. As results of all that, activation with ultrasound did not significantly alter the pH (p > 0.05). The cements were mixed with either DW or DW + PG, with the later association presenting higher pH at 15 days of assessment than the former (p < 0.05). Thereby, it can be concluded that mixing MTA with 80% DW and 20% PG increased the dentinal pH, which is positive for root resorption repair (AU).

Treatment outcomes of pulp revascularization in traumatized immature teeth using calcium hydroxide and 2% chlorhexidine gel as intracanal medication

Abstract Objective Pulp revascularization is an effective treatment for immature necrotic teeth. Calcium hydroxide has been used in pulp revascularization as an intracanal medication due to its antimicrobial action and the non-exhibition of crown discoloration and cytotoxicity for stem cells from the apical papilla. Our study aimed to investigate the clinical success and quantitative radiographic changes of root development in immature traumatized teeth using calcium hydroxide plus 2% chlorhexidine gel as intracanal medication. Methodology In this retrospective study, 16 patients were treated with a standardized pulp revascularization protocol. Calcium hydroxide and 2% chlorhexidine gel were manipulated in a 1:1 (v/v) ratio and inserted into root canals with Lentulo spirals (Dentsply Maillefer, Baillaigues, Switzerland). Patients were followed up for a period from 9 to 36 months for the evaluation of clinical and radiological data. Radiographic measurements of root length, root width, apical diameter, and MTA placement from the apex were quantified using software ImageJ. Wilcoxon test and t-test were used, according to nonparametric or parametric data, respectively, for changes over time in root length, root width, and apical diameter. Results Fifteen teeth survived during the follow-up period (93.75%) and met the criteria for clinical success. Although the changes seem to be very small in many cases, significant increases in the average root length (14.28%, p<0.0001), root width (8.12%, p=0.0196), and decrease in apical diameter (48.37%, p=0.0007) were observed. MTA placement from the apex and age at the time of treatment was not significantly associated with the quantitative radiographic outcomes. Conclusions Pulp revascularization in traumatized immature teeth treated with calcium hydroxide plus 2% chlorhexidine gel as intracanal medication had high success and survival rates, showing periodontal healing and resolution of signs and symptoms. However, concerning the continued root development, the outcomes can still be considered unpredictable.

Dental discoloration caused by Grey-MTAFlow cement: analysis of its physicochemical, biological and antimicrobial properties

Abstract Tricalcium silicate-based cement are materials used in reparative and regenerative procedures in endodontics. A recently proposed formulation aimed to enhance handling during clinical use with a versatile material applicable by syringe. Although, the use of bismuth oxide as radiopacifier and grey raw powder are drawbacks considering aesthetics. Objectives Evaluate physicochemical, biological, and antimicrobial properties of Grey-MTAFlow (Ultradent) and assess whether the addition of zinc oxide (ZnO) prevents dentinal discoloration caused by bismuth oxide. Methodology Grey-MTAFlow was manipulated in 'thin' consistency for all tests. Luminosity, color change, ion migration to dentine, radiopacity, setting time, ISO 6876:2012 linear flow, volumetric lateral flow and central filling of simulated grooves scanned using micro-computed tomography (μCT), pH, calcium release, volumetric change using μCT, chemical characterisation, cytotoxicity, and antimicrobial activity were assessed. Addition of 5% ZnO to Grey-MTAFlow and a bismuth-containing experimental composition were comparatively tested. Statistical analyses used Shapiro-Wilk, T-test, ANOVA, and Kolmogorov-Smirnov (p<0.05). Results The addition of ZnO to Grey-MTAFlow prevented dentine darkening after 90 days due to bismuth migration reduction, although no statistical difference was found (p=0.863). ZnO addition significantly enhanced Grey-MTAFlow radiopacity without differences in initial setting time. Grey-MTAFlow presented an ISO linear flow of 10.9 mm and a balanced volumetric lateral flow with central filling in μCT evaluation. All compositions presented an alkaline pH after immersion. Grey-MTAFlow had a significantly higher calcium ion release after 28 days in comparison to 24 hours (p=0.011) and volumetric expansion of 0.4±1.8% after immersion. ZnO addition altered the hydrated cement matrix once calcium hydroxide (portlandite) could not be detected in characterisation. Neither of the materials produced inhibition halos nor reduced bacterial turbidity, but all presented cytocompatibility above 100%. Conclusion Grey-MTAFlow expanded after immersion and exhibited higher luminosity values after the evaluation period when ZnO was added, but chemical modifications after this addition occurred.

Teaching experiences during the SARS-COV-2 pandemic in a Brazilian School of Dentistry

The coronavirus outbreak (2019) represents a public health emergency of global concern. Several measures have been taken to minimise the risk of infection among the population, including social distancing, working from home, closure of non-essential activities since the detection of the first case in Brazil. This study describes the teaching experiences during the SARS-COV-2 pandemic in a Brazilian School of Dentistry. The State University of Campinas (UNICAMP) was the first public university in Brazil to stop all the classroom activities on 13th of March 2020 due to COVID-19, followed by other universities. UNICAMP developed several initiatives and created a special support page for digital teaching, where it is possible to obtain guidance, support materials for teachers and a space for exchanging messages (e-mail and chat) for specific guidelines. UNICAMP has started lending computer equipment to undergraduate and graduate students according to socioeconomic criteria. Along with the equipment, 500 chips have been delivered with 10 GB of internet so that these students are able to access the network and carry out the remote activities related to their courses. In conclusion, quality education is the key-element in forming high-quality professionals that will in a near future provide health care for the community, be part in international research groups and become lecturers

Sealing ability of MTA, CPM, and MBPc as root-end filling materials: a bacterial leakage study

ABSTRACT Objectives To evaluate the sealing ability of three root-end filling materials (white MTA, CPM, and MBPc) using an Enterococcus faecalis leakage model. Material and Methods Seventy single-root extracted human teeth were instrumented and root-ends were resected to prepare 3 mm depth cavities. Root-end preparations were filled with white MTA, CPM, and MBPc cements. Enterococcus faecalis was coronally introduced and the apical portion was immersed in BHI culture medium with phenol red indicator. The bacterial leakage was monitored every 24 h for 4 weeks. The statistical analysis was performed using the Wilcoxon-Gehan test (p<0.05). Results All cements showed bacterial leakage after 24 hours, except for the negative control group. The MBPc showed significantly less bacterial leakage compared with the MTA group (p<0.05). No significant differences were found between the CPM and the other groups. Conclusions The epoxy resin-based cement MBPc had lower bacterial leakage compared with the calcium silicate-based cements MTA and CPM.

Analysis of the reaction of subcutaneous tissues in rats and the antimicrobial activity of calcium hydroxide paste used in association with different substances

The aim of this study was to evaluate the subcutaneous tissue response in rats and the antimicrobial activity of intracanal calcium hydroxide dressings mixed with different substances against E. faecalis. Fifty four rats were divided into three experimental groups according to the vehicle in the calcium hydroxide treatment: 0.4% chlorohexidine in propylene glycol (PG),Casearia sylvestris Sw in PG and calcium hydroxide+PG (control group). The pastes were placed into polyethylene tubes and implanted into the subcutaneous tissue. After 7, 14 and 30 days, the samples were processed and histologically evaluated (hematoxylin and eosin). The tissue surface in contact with the material was analyzed, and the quantitative analysis determined the volume density occupied by the inflammatory infiltrate (giant cells, polymorphonuclear cells and mononuclear cells), fibroblasts, collagen fibers and blood vessels. For the antimicrobial analysis, 20 dentin blocks infected with E. faecalis were treated with calcium hydroxide pastes in different vehicles; 0.4% chlorhexidine in PG, PG, extract fromCasearia sylvestris Sw in PG and a positive control (infection and without medication) for 7 days. The efficiency of the pastes was evaluated by the live/dead technique and confocal microscopy. The results showed that 0.4% chlorhexidine induced a higher inflammatory response than the other groups. The Casearia sylvestris Sw extract showed satisfactory results in relation to the intensity of the inflammatory response. In the microbiological test, there were no statistical differences between the evaluated intracanal dressings and the percentage of bacterial viability was between 33 and 42%. The control group showed an 86% viability. Antimicrobial components such as chlorhexidine or Casearia sylvestris Sw did not improve the antimicrobial activity against E. faecalis in comparison to the calcium hydroxide+PG treatment. In addition, the incorporation of chlorhexidine in the calcium hydroxide paste promoted the highest inflammatory response.

Rat subcutaneous tissue response to calcium silicate containing different arsenic concentrations

Objective: To evaluate the response of rat subcutaneous tissue in implanted polyethylene tubes that were filled with GMTA Angelus and Portland cements containing different arsenic concentrations. Material and Methods: Atomic absorption spectrophotometry was utilized to obtain the values of the arsenic concentration in the materials. Thirty-six rats were divided into 3 groups of 12 animals for each experimental period. Each animal received two implants of polyethylene tubes filled with different test cements and the lateral of the tubes was used as a control group. After 15, 30 and 60 days of implantation, the animals were killed and the specimens were prepared for descriptive and morphometric analysis considering: inflammatory cells, collagen fibers, fibroblasts, blood vessels and other components. The results were analyzed utilizing the Kuskal-Wallis test and the Dunn's Multiple test for comparison (p<0.05). Results: The materials showed, according to atomic absorption spectrophotometry, the following doses of arsenic: GMTA Angelus: 5.01 mg/kg, WPC Irajazinho: 0.69 mg/kg, GPC Minetti: 18.46 mg/kg and GPC Votoran: 10.76 mg/kg. In a 60-day periods, all specimens displayed a neoformation of connective tissue with a structure of fibrocellular aspect (capsule). Control groups and MTA Angelus produced the lower amount of inflammatory reaction and GPC Minetti, the highest reaction. Conclusions: There was no direct relationship between the concentration of arsenic present in the composition of the materials and the intensity of the inflammatory reactions. Higher values, as 18.46 mg/kg of arsenic in the cement, produce characteristics of severe inflammation reaction at the 60-day period. The best results were found in MTA angelus. .

Accuracy evaluation of three electronic apex locators in teeth with immature apices

Introduction and Objective: The aim of this randomized controlled study was to evaluate the accuracy of Root ZX, iPex and YS-RZ-A apex locators in tooth with incomplete apices. Material and methods: Thirty human mandibular pre-molars without dental caries, fracture and with 1-3mm apical diameter and ¾ of root development stage were used. After coronal access, tooth length was determined with the visualization of a K-file, compatible with the root canal diameter, at the apex. To determine the root canal length using electronic methods, the teeth were included in alginate. The 30 teeth were measured with the three apex locators until achieving the apex foramen. During the measurement, the canals were inundated with 1% sodium hypochlorite. Statistical analysis was performed using Qui-square test (p < 0.05). Results: The Root ZX apex locator showed the higher accuracy (53.3%), with statistical difference in relation to iPex apex locator (33.3%) and YS-RZ-A apex locator (26.7%) (p < 0.05). Regarding the security limit of ±1 mm, the Root ZX apex locator did not show statistical difference in comparison with iPex apex locator (p > 0.05), but both were statistically different in relation to YS-RZ-A apex locator (p < 0.05). Conclusion: The results showed that all the studied apex locators were efficient in determining the root canal length in tooth with incomplete apex, considering the tolerance of ±1 mm. The Root ZX apex locator showed the highest accuracy with 100% of agreement.

Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement

Objectives: To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement. Material and Methods: White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p<0.05). Results: The results showed an increase of the pH level after 15 days, followed by a slight increase after 30 days and a decrease after 60 days. There were no significant statistical differences among the groups (p>0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05). Conclusions: The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated. .

Alteração de cor de quatro cimentos obturadores de canais radiculares: an lise por meio de espectrofotometria / Color alteration of four root canal sealers: a spectrophotometer analysis

A descoloração dentária ‚ uma consequência diante de alguns cimentos endodônticos. O objetivo do estudo foi avaliar a alteração de cor e escurecimento de quatro cimentos obturadores (AH Plus, RealSeal SE, MTA fillapex e Acroseal). Trinta e seis anéis metálicos com um diâmetro inteno de 10 mm e 2 mm de espessura foram preenchidos com os cimentos. Foram utilizados nove anéis para cada cimento. Após o tempo de presa, os materiais foram removidos dos anéis e a cor mensurada em espectrofotômetro (Vita Easyshade, Vita Zahnfabrik H. Rauter, Alemanha). Após a medição inicial, as amostras foram levadas novamente … estufa a 37C e umidade relativa de 98% durante 24 horas. Após esse período, a cor dos cimentos foi mensurada novamente. Os resultados da alteração de cor (DE) foram submetidos ao teste não paramétrico de ANOVA/Tukey e a luminosidade (L) ao teste de Kruskal-Wallis/Dunn (p < 0,05). Os cimentos avaliados apresentaram alteração de cor entre a presa e após 24 horas de exposição … umidade. O cimento Acroseal apresentou escurecimento, sem diferença estat¡stica em relação aos demais.

Dental discoloration is an undesirable consequence verified for some endodontic materials. The aim of the study was to evaluate the color alteration and darkening of four endodontic sealers (AH Plus, RealSeal SE, MTA fillapex and Acroseal). Thirty-six stainless steel rings with an inner diameter of 10 mm and 2 mm of thickness were filled with the manipulated sealers. Nine rings were used for each sealer. After setting time, the sealers were demoulded and the color measured using a spectrophotometer (Vita Easyshade, Vita Zahnfabrik H. Rauter, Germany). After the initial assessment, the samples were kept in an incubator at 37øC and 98% of humidity for 24 hours. After the period, the color of the sealers was assessed again. The results of color alteration (DE) were submitted to the non-parametric ANOVA/Tukey test and to the Kruskal-Wallis/Dunn (p < 0.05) test for luminosity. All the evaluated sealers showed color alteration between the setting time and after 24 hours exposed to humidity. Acroseal sealer showed darkening, without statistical difference in comparison with the other evaluated sealers

Analysis of the color alteration and radiopacity promoted by bismuth oxide in calcium silicate cement

The aim of the study was to determine if the increase in radiopacity provided by bismuth oxide is related to the color alteration of calcium silicate-based cement. Calcium silicate cement (CSC) was mixed with 0%, 15%, 20%, 30% and 50% of bismuth oxide (BO), determined by weight. Mineral trioxide aggregate (MTA) was the control group. The radiopacity test was performed according to ISO 6876/2001. The color was evaluated using the CIE system. The assessments were performed after 24 hours, 7 and 30 days of setting time, using a spectrophotometer to obtain the ΔE, Δa, Δb and ΔL values. The statistical analyses were performed using the Kruskal-Wallis/Dunn and ANOVA/Tukey tests (p < 0.05). The cements in which bismuth oxide was added showed radiopacity corresponding to the ISO recommendations ( > 3 mm equivalent of Al). The MTA group was statistically similar to the CSC / 30% BO group (p > 0.05). In regard to color, the increase of bismuth oxide resulted in a decrease in the ΔE value of the calcium silicate cement. The CSC group presented statistically higher ΔE values than the CSC / 50% BO group (p < 0.05). The comparison between 24 hours and 7 days showed higher ΔE for the MTA group, with statistical differences for the CSC / 15% BO and CSC / 50% BO groups (p < 0.05). After 30 days, CSC showed statistically higher ΔE values than CSC / 30% BO and CSC / 50% BO (p < 0.05). In conclusion, the increase in radiopacity provided by bismuth oxide has no relation to the color alteration of calcium silicate-based cements.

Interfacial adaptation of an epoxy-resin sealer and a self-etch sealer to root canal dentin using the System B or the single cone technique

The aim of this laboratory study was to compare the interfacial adaptation of an epoxy-resin and a self-etch sealer in mesial root canals of mandibular molars filled using the System-B/Elements Obturation Unit. Sixty mesial root canals of mandibular molars were prepared using the K3 rotary system up to 35.04 instrument and then filled with the aid of the System-B/Elements Obturation Unit using either gutta-percha/ThermaSeal Plus (n=15) or Resilon/Real Seal SE (n=15). The single cone technique using both materials was used as control. The sealers were stained with Rhodamine B dye and the teeth were filled and sectioned at 2, 4 and 6 mm from the apex. The interfacial marginal adaptation of sealers was evaluated using confocal microscopy. Statistical analyses were performed by the Kruskall-Wallis test (α=0.05). In general, microscopic analysis showed a quite regular gap distribution pattern at sealer-dentin interfaces, mainly for the two groups filled with Real Seal SE. This means that both nonbonding root-filling groups (ThermaSeal Plus) showed significantly higher amount of gap-free regions regardless of the filling technique (p<0.05). Better marginal adaptation was obtained with gutta-percha and epoxy resin-based sealer using either the system B or the single cone technique.

O objetivo deste estudo laboratorial foi avaliar comparativamente a adaptação na interface obturação/dentina em canais mesiais de molares inferiores obturados com System B, tanto com guta percha/ThermaSeal Plus como com Resilon/Real Seal SE. Os canais mesiais de 60 molares inferiores foram modelados utilizando o sistema rotatório K3, realizando o batente apical com o instrumento 35,04. Em seguida os canais foram obturados com guta percha/ThermaSeal Plus (n=15) e com Resilon/Real Seal SE (n=15) por meio do System B. Obturações com a técnica do cone único utilizando os dois materiais foram empregadas como controle. Os cimentos foram corados com Rodamina B e os dentes obturados foram seccionados a 2, 4 e 6 mm do ápice. A adaptação da interface marginal foi avaliada utilizando a microscopia confocal. A análise estatística foi realizada empregando o teste Kruskall-Wallis (p<0,05). De modo geral, a análise microscópica mostrou um padrão regular na distribuição de fendas na interface cimento-dentina, principalmente para os dois grupos com cimento Real Seal SE. Sendo que os outros dois grupos (com ThermaSeal Plus), apresentaram uma quantidade significativamente menor de áreas com fendas, independentemente da técnica de obturação (p<0,05). A melhor adaptação marginal foi observada quando se utilizou guta percha e o cimento à base de resina epóxica, tanto com o System B como com cone único.

Evaluation of single root canals filled using the lateral compaction, tagger's hybrid, microseal and guttaflow techniques

The aim of this study was to determine the percentage of voids, gutta-percha and root canal sealer using 4 different filling techniques. Fifty-two extracted maxillary lateral incisors were prepared using the crown-down pressureless technique. The teeth were randomly divided in 4 groups (n=13): Lateral compaction (LC), Tagger's hybrid (TH), MicroSeal (MS) and GuttaFlow (GF) techniques. Horizontal cross-sections were made at the 2, 10 and 15 mm levels from the apex. Digital images of the root canal areas were acquired using a stereomicroscope and examined using the Image Tool 3.0 software. Statistical analysis was performed using the Kruskal-Wallis test (α=0.05). In general, a significant decrease in the gutta-percha filled area and increase of sealer area were observed at the apical level for all the evaluated techniques (p<0.05). With regard to the presence of voids, no significant difference was found. MS and TH techniques showed a larger gutta-percha filled area than LC and GF techniques at the coronal and middle third level (p<0.05). From the results of the present study, it may be concluded that the gutta-percha filled area of fillings decrease at the apical level, regardless of the filling technique used.

O objetivo do estudo foi determinar a porcentagem de espaços vazios, guta-percha e cimento após a obturação por 4 diferentes técnicas. Cinquenta e dois incisivos laterais superiores humanos extraídos foram instrumentados pela técnica coroa-ápice sem pressão. Os dentes foram randomicamente divididos em 4 grupos (n=13): Condensação lateral (LC), Técnica híbrida de Tagger (TH), MicroSeal (MS) e GuttaFlow (GF). Foram feitas secções horizontais a 2, 10 e 15 mm do ápice. Imagens digitais foram obtidas dos canais por meio de estereomicroscópio e analisadas no programa Image Tool 3.0. A análise estatística foi feita utilizando o teste de Kruskal-Wallis (α=0,05). Em geral foi observado um significante decréscimo na área de guta-percha e um aumento na área de cimento para todas as técnicas analisadas (p<0,05). Com relação à presença de espaços vazios, não houve diferença estatística entre as técnicas (p>0,05). As técnicas MS e TH apresentaram área de guta-percha maior que as técnicas LC e GF nos terços médio e cervical (p<0,05). Após análise dos resultados foi possível concluir que a área de guta-percha nas obturações diminui em sentido apical, independente da técnica utilizada.