Assessment of the root surface temperature during the use of intracanal agitation systems: In vitro study

Abstract This study aimed to evaluate the temperature changes that the different methods of agitation of irrigants promote on the external dental root surface. Nine extracted human lower premolars were standardized by cone-beam computed tomography and used. The root canal was instrumented with a Reciproc 40.06 file. Temperature measurement was performed using K-type thermocouple sensors attached to the middle, cervical, and apical thirds of the teeth. The teeth had their roots immersed in distilled water at 37ºC, which were distributed into 3 experimental groups according to the mechanical agitation methods to be studied. US Group (n=3), Irrisonic Ultrasonic Tip activated through ultrasound; EC Group (n=3), Easyclean Tip coupled to a contra-angle low-speed handpiece; XP Group (n=3), XP-endo Finisher file coupled to an endodontic electrical motor. Temperature measurements were performed simultaneously with agitation and irrigation of intracanal irrigants. Statistical analysis was performed using SPSS software with a significance level of 5%. For multiple comparisons, the Tukey test was used. The association between mechanical agitation methods and root third was statistically significant. Regarding the temperatures recorded on the external surface of the roots, the ultrasonic tip was significantly higher than the XP-endo Finisher file and the Easyclean tip, which did not differ from each other. Regarding the ultrasonic tip, the external temperature in the middle third (39.46ºC) of the root was significantly lower than in the cervical (40.41ºC) and apical third (40.53ºC). None of the agitation methods of irrigants studied presented heating above 47ºC, and their use is safe for periodontal tissues.

Resumo Este estudo teve como objetivo avaliar as mudanças de temperatura que os diferentes métodos de agitação de irrigantes promovem na superfície externa da raiz dentária. Nove pré-molares humanos extraídos foram padronizados por tomografia computadorizada de feixe cônico e usados. O canal radicular foi instrumentado com uma lima Reciproc 40.06 de 25 mm. A medição da temperatura foi realizada usando sensores termopares do tipo K fixados nos terços médio, cervical e apical dos dentes. Os dentes tiveram suas raízes imersas em água destilada a 37ºC, as quais foram distribuídas em 3 grupos experimentais de acordo com os métodos de agitação mecânica a serem estudados. Grupo US (n=3), Ponta Irrisonic Ultrasonic ativado por ultrassom; Grupo EC (n=3), Ponta Easyclean acoplada a um contra-ângulo de baixa rotação; Grupo XP (n=3), Lima XP-endo Finisher acoplada a um motor elétrico endodôntico. As medições de temperatura foram realizadas simultaneamente com agitação e irrigação de irrigantes intracanal. A análise estatística foi realizada no software SPSS com nível de significância de 5%. Para comparações múltiplas, foi utilizado o teste de Tukey. A associação entre métodos de agitação mecânica e terço radicular foi estatisticamente significativa. Em relação às temperaturas registradas na superfície externa das raízes, a ponta ultrassônica foi significativamente maior que a lima XP-endo Finisher e a ponta Easyclean, que não diferiram entre si. Com relação à ponta ultrassônica, a temperatura externa no terço médio (39,46ºC) da raiz foi significativamente menor do que nos terços cervical (40,41ºC) e apical (40,53ºC). Nenhum dos métodos de agitação dos irrigantes estudados (Irrisonic, XP-endo Finisher e Easyclean) apresentou aquecimento acima de 47ºC, sendo seu uso seguro para os tecidos periodontais.

Cyclic fatigue resistance of three reciprocating nickel-titanium instruments with heat treatment at intrachannel temperature

Introduction: the in vitro study compared the dynamic cyclic fatigue resistance of 3 reciprocating NiTi files with heat treatment. Methods: we distributed 30 new endodontic files in three groups. The endodontic files selected for this experiment were: AF Blue R3 25/06 (AFB) (Fanta Dental, Shanghai, China), X1 Blue File 25/06 (X1B) (MK Life, Porto Alegre, RS, Brazil), and Reciproc Blue 08/25 (RB) (VDW, Munich, Germany. We measured the time to file fractureand the length of the fractured fragment. ANOVA analysis was used, followed by the Tukey test for multiple comparisons, with a significance level of 5% (P < 0,05). Results: the mean time in seconds until the file fractured was 170.7 ±15,1 for AFB files, 110,4 ±26,8 for X1B, and 163,3 ±22,9 for RB files. This difference was statistically significant when comparing X1B to AFB (p: 0,000) and X1B to RB (p: 0,000). However, there are no statistically significant differences between RB and AFB (p:0,739). Conclussions: this study found that RB and AFB files exhibit similar resistance to cyclic fatigue.

Introducción: el estudio in vitro comparó la resistencia a la fatiga cíclica dinámica de 3 limas NiTi recíprocas con tratamiento térmico. Métodos: distribuimos 30 limas endodónticas nuevas en tres grupos. Las limas endodónticas seleccionadas para este experimento fueron: AF Blue R3 25/06 (AFB) (Fanta Dental, Shanghai, China), X1 Blue File 25/06 (X1B) (MK Life, Porto Alegre, RS, Brasil), y Reciproc Blue 08/25 (RB) (VDW, Munich, Alemania. Se midió el tiempo transcurrido hasta la fractura de la lima y la longitud del fragmento fracturado. Se utilizó el análisis ANOVA, seguido de la prueba de Tukey para comparaciones múltiples, con un nivel de significación del 5% (P < 0.05). Resultados: el tiempo medio en segundos hasta la fractura de la lima fue de 170.7 ±15.1 para las limas AFB, 110.4 ±26.8 para las X1B y 163.3 ±22.9 para las RB. Esta diferencia fue estadísticamente significativa al comparar X1B con AFB (p: 0.000) y X1B con RB (p: 0.000). Sin embargo, no hay diferencias estadísticamente significativas entre RB y AFB (p:0.739). Conclusiones: en este estudio se ha comprobado que las limas RB y AFB presentan una resistencia similar a la fatiga cíclica.

Evaluation of the rotary kinematics between actual and set speeds of X-Smart Plus, VDW.Silver and iRoot motors

Abstract The present study evaluated the actual rotational speed of three different endodontic motors compared to the values provided by the manufacturers. A total of three endodontic motors (X-Smart Plus, VDW.Silver, and iRoot) were tested at 400 rpm and 800 rpm and 2 N/cm2 torque. The kinematics of the devices was recorded by using a custom angle-measuring disc with a 50-mm diameter attached to the handpiece provided by the manufacturer, whereas their movement was captured by a high-speed camera at 2,400 frames per second, 800 x 800 pixel-resolution and distance of 0.3 m from the target object. Statistical analysis was performed at a significance level of 5%. At 400 rpm, the iRoot motor had a value of 17.94 rpm above that indicated by the manufacturer, which was significantly different from those of X-Smart Plus (5.20 rpm below that indicated by the manufacturer) and VDW.Silver (0.62 rpm above that indicated by the manufacturer) motors (P < 0.05). At 800 rpm, the iRoot motor had a value of 51.34 rpm below that indicated by the manufacturer, whereas the X-Smart Plus motor had a value of 13.00 rpm below that indicated by the manufacturer (P > 0.05). The VDW.Silver motor statistically differed from the iRoot and X-Smart Plus ones, showing a value of 1.68 rpm above that indicated by the manufacturer. In conclusion, the X-Smart Plus, VDW.Silver, and iRoot motors showed lower variations in the rotational speed values compared to those reported by their manufacturers. The endodontic motors presented different behaviors between them, with the VDW.Silver motor presents the most accurate values and the iRoot presents the most divergent values.

Resumo O presente estudo avaliou a real velocidade rotacional de três diferentes motores endodônticos comparados aos valores fornecidos pelos fabricantes. Um total de três motores endodônticos (X-Smart Plus, VDW.Silver e iRoot) foram testados a 400 rpm e 800 rpm e torque de 2 N/cm2. A cinemática dos dispositivos foi verificada utilizando-se um disco customizado de 50 mm de diâmetro acoplado ao contra ângulo fornecido pelo fabricante e o movimento foi capturado através de uma câmera ajustada em 2400 quadros por segundo com resolução de 800 x 800 pixels distante 0,3 m do objeto alvo. A análise estatística foi realizada com nível de significância de 5%. A 400 rpm, o motor iRoot apresentou 17,94 rpm acima do indicado pelo fabricante, sendo o valor significativamente diferente do X-Smart Plus (5,20 rpm abaixo do indicado pelo fabricante) e VDW.Silver (0.62 rpm acima do indicado pelo fabricante) (P > 0,05). A 800 rpm, iRoot apresentou 51.34 rpm abaixo do indicado pelo fabricante e X-Smart Plus 13,00 rpm abaixo do indicado pelo fabricante (P > 0,05). VDW.Silver foi estatisticamente diferente de iRoot e X-Smart Plus, apresentando 1,68 rpm acima do indicado pelo fabricante. Concluiu-se que os motores X-Smart Plus, VDW.Silver e iRoot apresentaram baixa variação na velocidade rotacional quando comparada ao fornecido pelo fabricante. Os motores endodônticos apresentaram diferentes comportamentos entre eles, sendo que o motor VDW.Silver apresentou valores mais acurados enquanto o iRoot foi o mais divergente.

Influence of different working lengths on the shaping ability of Reciproc Blue in the apical third and apical foramen: a micro-computed tomographic study

Aim: This study aimed to assess the shaping ability of Reciproc Blue in the apical third and apical foramen of moderately curved canals at different working lengths (WLs), by micro-computed tomography. Methods: Thirty-six mesial roots (mesiobuccal and mesiolingual canals) were included, each with 2 separate root canals and independent apical foramina, according to type IV of Vertucci's classification of first and second mandibular molars. The canals were instrumented at three different WLs: G-1, 1mm short of the major apical foramen; G0, at the major apical foramen; G+1, 1mm beyond the major apical foramen. The groups were assessed for changes in root canal volume and untouched wall area in the apical third. Groups G0 and G+1 were also compared for percentage of untouched walls at the apical foramen. One-way ANOVA (post hoc Tukey test) and Student's t-test adopted a 5% level of significance. Results: Root canal volumes (mm3) in the apical third were 22.86±10.46, 44.48±24.91, and 55.71±21.32 in G-1, G0 and G+1, respectively. G-1 volume following instrumentation increased significantly less than that of G0 or G+1 (P>.05); G0 did not differ from G+1. The percentage of untouched wall area in the apical third did not differ among the three groups (P>.05). G0 and G+1 did not differ regarding untouched walls in the major apical foramem walls. Conclusion: Extending the WL from 1mm short of the apical foramen to a point at and beyond the WL increases the apical third volume without increasing the prepared area. Untouched surface areas of the apical foramen were not modified by instrumentation at or beyond the foramen

Reciprocating Kinematics of X-Smart Plus, VDW Silver and, iRoot Endodontic Motors: A Comparison Between Real and Set Values

Abstract This study assessed 3 endodontic motors, X-Smart Plus (Dentsply Sirona, Ballaigues, Switzerland), VDW.Silver Reciproc (VDW GmbH, München, Germany) and, iRoot (Bassi Endodontics, Belo Horizonte, Brazil) in 2 different reciprocating settings. The movements evaluated were 170° in counter-clockwise (CCW) and 50° in clockwise (CW) at 350 RPM, and 150° CCW and 30° CW at 300 RPM. For the X-Smart Plus and VDW Silver the settings used were the ones in the motor library. For the iRoot, the motor was adjusted to the angles of the study. A customized optic target was attached to the contra-angle of the motor and the movements were recorded with a high-resolution camera (K2 DistaMaxTM Long-Distance Microscope System, Infinity Photo-Optical Company, Colorado, EUA) at 2,400 frames per second (FPS). The images were analyzed with the Vision Research software (Inc. Headquarters, Wayne, New Jersey, EUA). The following kinematic parameters were assessed: CCW angle, CW angle, speed (RPM) at both directions, and, standstill time at each change of directions. The Intraclass Correlation Coefficient (ICC) and Kruskal-Wallis (method of Dunn) were used at a significant level of 5%. There was no statistically significant difference among the motors at the 150°/30° setting (P > .05); the iRoot was the least reliable at the 170°/50° setting for CCW angle, speed, and net angle parameters (P < 0.05). The standstill time of all motors in both directions was identical. None of the motors were able to reproduce faithfully the set movements. The iRoot motor presented a higher discrepancy when compared to X-Smart and VDW Silver.

Resumo Este estudo avaliou 3 motores endodônticos, X-Smart Plus (Dentsply Sirona, Ballaigues, Suíça), VDW.Silver Reciproc (VDW GmbH, Munique, Alemanha) e iRoot (Bassi Endodontics, Belo Horizonte, Brasil) em 2 diferentes ajustes de movimento reciprocante. Os movimentos analisados foram: 170° em sentido anti-horário (CCW) e 50° em sentido horário (CW) a 350 RPM, e 150° CCW e 30° CW a 300 RPM. Para os motores X-Smart Plus e VDW Silver os ajustes usados foram os que se apresentam nos ajustes pré-definidos dos motores. Para o iRoot o motor foi ajustado para os ângulos do estudo. Um alvo ótico customizado foi preso ao contra ângulo do motor e os movimentos foram gravados com uma câmara de alto resolução (K2 DistaMaxTM Long-Distance Microscope System, Infinity Photo-Optical Company, Colorado, EUA) a 2.400 quadros por segundo (FPS). As imagens foram analisadas com o sotware Vision Research (Inc. Headquarters, Wayne, Nova Jersey, USA). Os seguintes parâmetros de cinemática foram avaliados: ângulo anti-horário, ângulo horário, ângulo líquido, velocidade (RPM) em ambas direções e tempo de parada a cada mudança de direção. O Coeficiente de Correlação Intraclasse (ICC) e o teste de Kruskal-Wallis (método de Dunn) foram usados com nível de significâncias de 5%. Não houve diferença estatisticamente significante entre os motores no ajuste de 150°/30° (P > .05); o motor iRoot foi o menos confiável no ajuste de 170°/50° para o ângulo anti-horário, velocidade e ângulo líquido (P < 0.05). O tempo de parada em todos os motores foi idêntico em ambas as direções. Nenhum dos motores foi capaz de reproduzir fielmente os movimentos. O motor iRoot apresentou maior discrepância quando comparado com o X-Smart Plus e VDW Silver.

Estudo da anatomia de incisivos inferiores em uma população da região Sudeste brasileira, usando TCFC / CBCT assessment of mandibular incisors anatomy in a population from Southeastern Brazil

Objetivo: Avaliar, por meio de tomografia computadorizada de feixe cônico (TCFC), a morfologia dos canais radiculares de dentes incisivos inferiores, em uma população da região Sudeste brasileira, e sua relação com a idade e o sexo dos pacientes Métodos: Foram analisados 371 prontuários de pacientes de ambos os sexos que continham exames de TCFC, totalizando 1.484 dentes incisivos inferiores. As imagens tomográficas foram capturadas com o tomógrafo Orthopantomograph OP300, com voxel de 0,20mm. A morfologia dos dentes foi avaliada de acordo com a classificação de Vertucci, e foram investigados os efeitos do sexo e da idade dos pacientes sobre a variação na morfologia desses dentes. Resultados: Todos os dentes avaliados apresentaram apenas uma raiz; 80,7% dos incisivos inferiores apresentaram um único canal (Tipo I de Vertucci). O segundo canal esteve presente em 19,3% dos casos, sendo do Tipo II de Vertucci em 1,1%, Tipo III em 18,1%, Tipo IV em 0,1% e Tipo V em 0,1%. Não houve influência estatisticamente significativa (p=0,890) do sexo na morfologia dos incisivos inferiores. Dentro da faixa etária analisada, os indivíduos com menos de 18 anos e aqueles com 40 a 49 anos (28,2% e 26,8% respectivamente) apresentaram significância estatística (p=0,001) quanto à presença de segundo canal, compa- rados aos de outras faixas etárias. Conclusões: A morfologia mais prevalente foi a Tipo I de Vertucci, seguida pelo Tipo III, sem diferença entre os sexos, e com maior prevalência de variação morfológica nos indivíduos com menos de 18 anos e com 40 a 49 anos de idade (AU).

Objective: Evaluate the root canal morphology of per- manent mandibular incisors, through the use of cone bean computed tomography (CBCT) in a population of Brazilian southeast region and its relationship with patient age and sex. Methods: A total of 1,484 mandibular incisors of 371 male and female patient`s medical records were analyzed using CBCT. The tomographic images were by the orthopantomograph OP300 tomograph, with voxel of 0.20 mm. The morphology of the teeth was evaluated according to the classification of VERTUCCI, and the effects of sex and age of the patients on the variation in the morphology of these teeth were investigated. Results: All evaluated teeth had only one root. A single canal (Ver- tuccis type I) was detected in 80.7% of mandibular incisors. The second canal was present in 19.3% of the cases, with rates of 1.1% for Type II, 18.1% for Type III, 0.1% for Type IV, and 0.1% for Type V. According to sex, there was no statistical difference (p = 0.890) in mandibular incisor morphology. Within the analyzed age group, individuals aged under 18 years and individuals between 40 and 49 years (28.2% and 26,8% respectively) were statistically significant (p = 0.001) when compared to the other age groups. Conclusions: The most prevalent morphology was Type I of VERTUCCI, followed by Type III, without difference between sex and with a higher prevalence of morphological variation in individuals with less than 18 years and between 40 and 49 years (AU).

Tratamento de reabsorção radicular interna perfurante em incisivo central superior: relato de caso / Management of perforating internal root resorption in maxillary central incisor: case report

Introdução: Reabsorção radicular interna é a perda progressiva de dentina intrarradicular como resultado de atividades clásticas. Geralmente, mantém-se assintomática e é diagnosticada durante o exame radiográfico de rotina. O correto diagnóstico é de extrema importância para evitar a terapêutica inadequada, já que, em alguns casos, sua progressão pode resultar na perda do elemento dentário. Objetivo: O objetivo do presente trabalho é relatar um caso clínico de perfuração radicular causada por uma reabsorção interna inflamatória em incisivo central superior, em terço médio da raiz, com integridade do terço apical. Métodos: O tratamento foi realizado usando técnica de obturação com cones de guta-percha e cimento endodôntico à base de resina epóxi no terço apical e agregado trióxido mineral na área da reabsorção, com auxílio do microscópio operatório. Resultado: Após um período de três anos de acompanhamento clínico e radiográfico, pode-se confirmar o processo de reparo, demonstrando que é possível obter sucesso em casos de reabsorção perfurante. Conclusão: Mesmo em casos em que há comunicação da polpa dentária com tecidos periodontais, é possível salvar o elemento dentário com o diagnóstico preciso e tratamento correto.

Introduction: Internal root resorption is the progressive destruction of intraradicular dentin as a result of clastic activities. It is usually asymptomatic and discovered by chance on routine radiographic examinations. Is of vital importance to make a correct diagnosis so that the appropriate treatment can be provided because in some cases can result in destruction of the dental element. Objective: The aim of this study is to report a case of successful non-surgical management of perforating internal resorption in an maxillary central incisor, in the middle third of the root. Materials and Methods: The treatment was successfully performed with the aid of an operative microscope. The apical third was filled with guttapercha and epoxy-resin-based sealer and the perforation site it was repaired with mineral trioxide aggregate. Conclusion: Clinical findings and periapical radiographs show that the symptoms and signs ceased, and the results were satisfactory at 3-years follow-up with radiographic examination (AU).

Avaliação do tratamento endodôntico em sessão única e retratamento não cirúrgico com alargamento foraminal de dentes com periodontite apical / Evaluation of single visit endodontic treatment and non-surgical retreatment with foraminal enlargment of teeth with apical periodontitis ?

Objective: to evaluate the root canal treatment (RCT) and non-surgical root canal retreatment (NSRCR), associated with foraminal enlargement, performed on a singlevisit. Material and Methods: 125 teeth with apical periodontitis and follow-up period ranging from 6 to 12 months were included. The success was considered by the absence of signs and symptoms and complete or incomplete periapical repair. Logistic regression analyses were used to identify factors associated with the repair (p<0.05). Results: RCT showed 71.58% of complete healing and 23.16% of acceptable healing. NSRCR showed 80% of complete healing and 20% of acceptable healing. Age, gender, type of treatment and preoperative pain were not statistically significant for the healing process (p>0.05). Premolars showed the greatest chance of periapical repair. Pulp Canal Sealer showed a greater chance of periapical repair when compared to Sealapex (p<0.05). Conclusion: RCT and NSRCR using a foraminal enlargement protocol provided a favorable prognosis of periapical healing

Objetivo: avaliar o tratamento endodôntico (TE) e o retratamento não cirúrgico do canal radicular (RNCCR), associado a ampliação foraminal, realizado em sessão única. Material e Métodos: foram incluídos 125 dentes com periodontite apical e proservação de 6 a 12 meses. O sucesso foi considerado pela ausência de sinais e sintomas e reparo periapical completo ou incompleto. Análises de regressão logística foram utilizadas para identificar fatores associados ao reparo (p<0,05). Resultados: o TE mostrou 71,58% de cicatrização completa e 23,16% de cicatrização aceitável. O RNCCR mostrou 80% e 20% cicatrização completa e aceitável, respectivamente. Idade, sexo, tipo de tratamento e dor pré-operatória não foram estatisticamente significantes para o processo de cicatrização (p>0,05). Os pré-molares apresentaram a maior chance de reparo periapical. O cimento Pulp Canal Sealer mostrou maior chance de reparo periapical quando comparado ao Sealapex (p<0,05). Conclusão: o TE e RNCCR utilizando um protocolo de alargamento foraminal, proporcionaram um prognóstico favorável da cicatrização periapical

Current trends in technological armamentarium and treatment among Brazilian endodontists

Aim: To determine the current trends in technological armamentarium and endodontic treatment among Brazilian endodontists. Methods: A total of 279 endodontists answered a web-based survey questionnaire about their region of activity in Brazil and years as a specialist, average number of endodontic cases treated per month, number of visits to complete the treatment, use of rubber dam for isolation, type of irrigant, obturation technique and device used for this purpose, temporary filling materials, and greater difficulty encountered during treatment and technological armamentarium. A descriptive analysis, expressed in terms of frequency and percentage, was performed and the data were correlated using the chi-square test (p<0.05). Results: Most of the respondents had up to 10 years as specialists. More than 50% of endodontists preferred to complete the endodontic treatment in a single visit. Ninety-nine percent of endodontists used rubber dam for isolation. NaOCl was the most widely used irrigant. Most of the respondents associated different techniques for root canal filling. Lateral condensation and Continuous wave of condensation were the isolated technique most reported. Filling devices (thermocompactors) were used by 53% of endodontists. Glass ionomer was the preferred temporary filling material. The answers for the use of technological armamentarium revealing that 94% of endodontists used an apex locator; 67.38% utilized magnification (loupe: 23.66%; microscope: 35.48%; microscope and loupe: 8.24%); 58% reported to digital radiography; and 47.31% used computed tomography as a complementary tool. About mechanized instrumentation, 44.44% endodontists employed rotary and reciprocating files. The difficulties encountered during endodontic treatment were classified as preparation > access > obturation > anesthesia > isolation. Conclusions: Most endodontists have implemented new technologies, such as mechanical instrumentation, apex locators, magnification, digital radiography, computed tomography, ultrasound, and obturation tools, in their clinical practice (AU)