Imaginologic resources used in diagnosis of root resorptions: comparative study / Recursos imaginológicos utilizados no diagnóstico de reabsorções radiculares: estudo comparativo

ABSTRACT Objective: Compare the accuracy of early diagnosis of simulated internal root resorptions and external root resorption, using digital periapical radiography and cone beam computed tomography. Methods: Root resorption were simulated in extracted human teeth by demineralization with 5% nitric acid solution and 8% Sodium Hypochlorite in different periods (1 and 5 days). For the group external root resorption (n=12) composite resin cylinders were positioned on middle third of buccal surface of roots, to delimit application of demineralization substances. In group internal root resorptions (n=12) the teeth were sectioned longitudinally, and the composite resin cylinders were positioned in the middle third of root canals. The teeth were mounted in a dry mandible and evaluated by digital radiography and tomography. The images were evaluated by two examiners. Results: Analyzing the tomographic images in period of 1 day, the examiner 2 identified internal root resorptions that were not identified in radiographic images (p<0.05). No examiner was capable of diagnosing external root resorption irrespective of exam, in the group of 1 day (p>0.05). In 5 day period of induction, both exams identified internal root resorptions (p>0.05), however, the tomographic images were more effective in identifying external root resorption (p <0.05) for both examiners. Conclusion: Cone beam computed tomography was shown to be more effective than digital periapical radiography for detecting internal root resorptions with 1 day of induction. The imaginological resources used in this study were not able to early detect external root resorption.

RESUMO Objetivo: Comparar a acurácia do diagnóstico precoce de reabsorções radiculares interna (RRI) e reabsorções radiculares externa (RRE) simuladas, por meio de radiografia periapical digital e tomografia computadorizada de feixe cônico. Métodos: Reabsorções radiculares foram simuladas em dentes humanos extraídos utilizando a desmineralização com ácido nítrico 5% e hipoclorito de sódio 8% em diferentes períodos (1 e 5 dias). Para o grupo reabsorções radiculares externa (n=12) cilindros de resina composta foram posicionados no terço médio das faces vestibulares das raízes, delimitando a aplicação das substâncias de desmineralização. No grupo reabsorções radiculares interna (n=12) os dentes foram seccionados longitudinalmente, e os cilindros de resina posicionados no terço médio dos canais radiculares. Os dentes foram montados em mandíbula seca e avaliados por meio de radiografia digital e tomografia por dois examinadores. Resultados: Nas imagens tomográficas no período de 1 dia, o examinador 2 identificou reabsorções radiculares interna as quais não foram identificadas nas radiografias (p<0,05). Nenhum examinador foi capaz de diagnosticar as reabsorções radiculares externa independente do exame no grupo de 1 dia (p>0.05). No período de indução de 5 dias ambos os exames identificaram as reabsorções radiculares interna (p>0,05), entretanto, as tomografias foram mais eficazes na identificação das reabsorções radiculares externa (p<0,05) para ambos os examinadores. Conclusão: A tomografia computadorizada de feixe cônico mostrou-se mais eficaz do que a radiografia periapical digital na detecção de reabsorções radiculares interna com 1 dia de indução. Os recursos imaginológicos utilizados neste estudo não foram capazes de detectar precocemente a reabsorção radicular externa.

Ex-vivo Smear Layer Removal Efficacy of Two Activated Irrigation Techniques After Reciprocating Instrumentation in Curved Canals.

INTRODUCTION: This study aimed to compare the effectiveness of two activated irrigation techniques in removing the smear layer after single-file reciprocating instrumentation in curved canals. MATERIALS AND METHODS: Sixty distobuccal roots of maxillary molars were standardized to create a closed system, and then instrumented using WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) instruments. Fifty-four specimens were randomly distributed into 3 groups for final irrigation: Non-activated irrigation, passive ultrasonic irrigation (PUI), and EndoActivator (EA;Dentsply Maillefer, Tulsa, USA) irrigation. All specimens received 3 mL of 17% EDTA for 1 minute, followed by irrigation with 6 mL of 2.5% NaOCl. The apical, middle and cervical thirds of the specimens were analyzed using scanning electronic microscopy (SEM), and the amount of remaining smear layer on the canal walls was rated by three examiners using a five-category scoring system. Kendall's concordance coefficient was used to assess inter-rater agreement. Kruskal-Wallis and Mann-Whitney (Bonferroni) tests were used to compare the scores. RESULTS: Kendall's concordance coefficient was ≥ 0.7, indicating an excellent level of agreement between the raters. No statistically significant difference in irrigation techniques efficacy for removal of the smear layer (p=0.061) was found for the apical third. The scores attributed to the specimens irrigated with the EA system were significantly lower than those of the other groups in the cervical and middle thirds (p< 0.05). CONCLUSIONS: The efficacy of the EA system in removing the smear layer in the cervical and middle thirds of root canals instrumented with reciprocating motion was significantly higher than that of either PUI or non-activated irrigation. Both EA and PUI performed similarly in apical third.

Effect of laser (λ 660 nm) and LED (λ 630 nm) photobiomodulation on formocresol-induced oral ulcers: a clinical and histological study on rodents.

The aim of this study was to evaluate, clinically and histologically, the influence of laser and LED photobiomodulation in the healing of formocresol-induced oral mucosa ulcers of rats. We used 60 Wistar rats in which oral ulcers were induced on the gingiva of the lower incisors. Forty-eight hours after inducing the ulcers, the animals were divided into three groups: laser, LED, and untreated. Animals from the laser group received irradiation with GaAlAs, 660 nm, CW, 40 mW, φ 4 mm(2), 4.8 J/cm(2). Animals from the LED group received irradiation with InGaAIP, 630 nm, 150 mW, 4.8 J/cm(2), 0.8 cm spot. Forty-eight hours after oral ulcer induction, both irradiations were applied in a punctuate manner in the center of the ulcer at 48-h interval until the end of the experimental period. The animals were killed at 3, 5, 7, and 11 days after day 0. The results of the clinical evaluation showed that the laser and LED phototherapies were able to accelerate the healing of formocresol-induced oral ulcers, which occurred first in the laser group (ANOVA, p < 0.05). Histologically, there was a slight variation between LED and laser therapy; therefore, the laser group proved to be effective in accelerating wound healing, especially at 5 days, whereas the LED group was more effective at the end of the experimental period. It was concluded that laser and LED photobiomodulation were effective in accelerating the healing of formocresol-induced oral ulcers in both clinical and histological aspects.

Infiltration of Rhodamin B into three materials used as cervical barrier / Infiltração da Rodamina B em três materiais utilizados como tampão cervical

OBJECTIVE: To evaluate in vitro the sealing ability of three materials used as cervical barrier for internal dental bleaching. METHODS: Thirty-three canines were selected, and after biomechanical root canal preparation, the canals were filled by lateral condensation technique. After the filling material setting reaction, the teeth were randomly divided into three groups of ten teeth each, according to the following materials for constructing the cervical barrier: X Temp LC; Vitro Fil; Coltosol. The control group consisted of three teeth, without placement of the cervical cap. Sodium perborate /distilled water associated with 2% Rhodamin B were used as bleaching substance. After placing the bleaching agent in the pulp chamber, access cavities were sealed with temporary cement IRM and samples were stored at 37 ° for 7 days. After this period, the samples were cleaved longitudinally, and leakage was evaluated by the visual method. The data were submitted to Pearson test with a 5% level of significance. RESULTS: No statistically significant difference was found between the study groups, however, the largest number of specimens with a lower degree of leakage were found in the Coltosol group. CONCLUSION: All the materials evaluated for making the cervical cap allowed some level of leakage. .

OBJETIVO: Avaliar in vitro a capacidade seladora de três materiais utilizados como barreira cervical durante o clareamento interno. MÉTODOS: Foram selecionados trinta e três caninos humanos, que após o preparo biomecânico dos canais radiculares, foram obturados pela técnica da condensação lateral ativa. Após a reação de presa do material obturador os dentes foram divididos aleatoriamente em três grupos de dez dentes cada, de acordo com os seguintes materiais para confecção da barreira cervical: X Temp LC; Vitro Fil; Coltosol. O grupo controle constituiu de três dentes sem a confecção do tampão cervical. Utilizou-se como substância clareadora o Perborato de Sódio/ água destilada associado à Rodamina B 2%. Após a colocação do agente clareador na câmara pulpar, as aberturas coronárias foram seladas com cimento provisório IRM e as amostras foram armazenadas em estufa a 37° por 7 dias. Após esse período, as amostras foram clivadas no sentido longitudinal, e a avaliação da infiltração foi realizada pelo método visual. Os dados foram submetidos ao teste estatístico de Kruskal-Wallis, com nível de significância de 5%. RESULTADOS: Não houve diferença estatisticamente significante entre os grupos de estudo, embora o Coltosol tenha obtido maior número de espécimes com menor grau de infiltração. ...

Use of cone-beam tomography and digital subtraction radiography for diagnosis and evaluation of traumatized teeth treated with endodontic surgery and MTA. A case report.

The aim of this paper was to report the diagnosis and evaluation of periradicular bone repair by using computed tomography and digital subtraction radiography in an endodontic surgery case treated with mineral trioxide aggregate (MTA). The patient had local swelling and fistula 7 years after trauma in the upper jaw. Periapical lesion on tooth #12 and root resorption of tooth #11 were detected radiographically. Endodontic therapy and placement of intracanal medication were carried out. After 3 months, with no improvement in the clinical signs and symptoms, computed tomography was performed, showing extensive apical bone resorption on tooth #12 and dental resorption promoting communication of the root canal with the periodontium of tooth #11. The patient was referred to endodontic surgery. After surgery and postoperative periods of 15, 30, 60, 90, and 120 days, standardized radiographs were taken, digitized, and subjected to digital subtraction of the images using Adobe Photoshop CS software. Four years later, a cone-beam computed tomography was performed, showing bone repair and absence of root resorption at tooth #11. In this clinical case, digital subtraction radiography was effective for early detection of new bone formation and evolution of repair.

In vitro evaluation of root canal preparation using oscillatory and rotary systems in flattened root canals

OBJECTIVE: The aim of this study was to evaluate the biomechanical preparation of flattened root canals using the following systems: Endo-Eze AET stainless steel oscillatory instruments (Ultradent) and RaCe rotary NiTi instruments (FKG Dentaire). MATERIAL AND METHODS: Twenty extracted human mandibular incisors were randomly assigned to two groups: Group 1 - Instrumentation with oscillatory Endo-Eze AET files (oscillatory technique); Group 2 - Instrumentation with rotary NiTi RaCe files (rotary technique). The teeth were decoronated, had their apices and coronal openings sealed with sticky wax and were embedded in crystal-clear orthophtalic polyester resin. The roots were sectioned transversally with diamond discs at 10 mm (middle third) and 5 mm (apical third) from the apex and the segments were reassembled for instrumentation. The sections were photographed before and after root canal instrumentation and evaluated with respect to whether the original root canal shape was modified by instrumentation. To evaluate the differences in the root canal shape before and after biomechanical preparation, scores were given regarding the instruments touch on the intracanal walls. RESULTS: In middle third of the root canals instrumented with the rotary system, there was a change in the original canal anatomy (p<0.05), with formation of a protuberance in the mesiodistal direction. This protuberance did not occur when the oscillatory instrumentation was used. The oscillatory system had better results in the middle and apical thirds as evaluated by Dunn's multiple-comparison test (p>0.05). CONCLUSION: Under the tested conditions, Endo-Eze oscillatory system yielded the instrumentation of all flattened root canal walls, maintaining the canal original shape throughout the biomechanical preparation, and was more effective than RaCe rotary system.

In vitro evaluation of root canal preparation using oscillatory and rotary systems in flattened root canals.

OBJECTIVE: The aim of this study was to evaluate the biomechanical preparation of flattened root canals using the following systems: Endo-Eze AET stainless steel oscillatory instruments (Ultradent) and RaCe rotary NiTi instruments (FKG Dentaire). MATERIAL AND METHODS: Twenty extracted human mandibular incisors were randomly assigned to two groups: Group 1 - Instrumentation with oscillatory Endo-Eze AET files (oscillatory technique); Group 2 - Instrumentation with rotary NiTi RaCe files (rotary technique). The teeth were decoronated, had their apices and coronal openings sealed with sticky wax and were embedded in crystal-clear orthophtalic polyester resin. The roots were sectioned transversally with diamond discs at 10 mm (middle third) and 5 mm (apical third) from the apex and the segments were reassembled for instrumentation. The sections were photographed before and after root canal instrumentation and evaluated with respect to whether the original root canal shape was modified by instrumentation. To evaluate the differences in the root canal shape before and after biomechanical preparation, scores were given regarding the instruments touch on the intracanal walls. RESULTS: In middle third of the root canals instrumented with the rotary system, there was a change in the original canal anatomy (p<0.05), with formation of a protuberance in the mesiodistal direction. This protuberance did not occur when the oscillatory instrumentation was used. The oscillatory system had better results in the middle and apical thirds as evaluated by Dunn's multiple-comparison test (p>0.05). CONCLUSION: Under the tested conditions, Endo-Eze oscillatory system yielded the instrumentation of all flattened root canal walls, maintaining the canal original shape throughout the biomechanical preparation, and was more effective than RaCe rotary system.

Cirurgia paraendodôntica utilizando o MTA como material retrobturador: relato de casos / Surgery endodontics using MTA as root - end filling material: report of cases

A cirurgia paraendodôntica é o tratamento de lesões perirradiculares através de um conjunto de procedimentos por meio cirúrgico, cujo objetivo visa resolver complicações do tratamento endodôntico. A obturação retrógrada, uma das modalidades da cirurgia paraendodôntica, consiste na remoção do ápice da raiz, seguida de um preparo de uma cavidade e obturação desse espaço com material adequado. Vários materiais têm sido propostos, com o objetivo de promover o adequado selamento do canal radicular por via retrógrada, dentre os quais podemos citar o Super- EBA, o amálgama e o MTA. Este trabalho se constitui de uma revisão de literatura e relato de dois casos de cirurgia paraendodôntica, utilizando o MTA como material retrobturador.

Análise comparativa, in vitro, de 4 técnicas de preparo biomecânico em raízes mesiais de molares inferiores / An, in vitro, comparative assesment of four different canal instrumentation technique in mesial roots of lower molares

O presente estudo teve por finalidade avaliar e comparar o preparo biomecânico em raízes mesiais de molares inferiores, mediante quatro técnicas de instrumentação. Para isso, foram utilizados 32 molares inferiores humans extraidos. Após abertura coronária, uma lima tipo K número 10 foi introduzida nos canais mesiais para obtenção da odontometria. Os dentes foram incluídos em resina ortofitálica cristal e as raízes sofreram cortes transversais nos terços cervical e apical, logo em seguida, reposicionados para instrumentação como limas tipo K e Hedstroem (grupo 1), limas ultra-sônicas (grupo 2), limas NiTi rotatória (grupo 3), limas NiTi manual (grupo 4). As secções foram fotografadas antes da instrumentação e após a utilização dos instrumentos, para avaliação do desvio do eixo axial. Os resultados mosraram que no terço cervical e grupo 4 mostrou uma maior quantidade de preparo sem desvio (62,5%), seguido do grupo 3 (50%), do grupo 2 (255) e do grupo 1 (0%). No terço apical, o grupo 3 apresentou uma maior quantidade de secções sem desvio (50%), seguido dos grupos 4 (37,5%), 1 (37,5%) e 2 (25%). Dos 8 dentes instrumentados por grupo, o grupo 3 apresentou 37,5% (3 casos) de preparos sem desvio, seguido de grupo 4, 25% (2 casos). Nos grupos 1 e 2 todos os espécimes apresentaram desvio do centro axial do canal radicular.

Avaliação histopatológica do reparo apical e periapical em dentes de cães com vitalidade pulpar, após tratamento de canais radiculares utilizando dois cimentos obturadores à base de resina epóxica. Análise do pH e concentração de cálcio total / Histopathological evaluation of the apical and periapical repair of dog's teeth with vital pulp after biomechanic preparation and root canal fillings using resin-based sealers. Analysis of pH and calcium concentration

O objetivo do presente estudo foi o de avaliar comparativamente, dois cimentos obturadores de canal radicular à base de resina epóxica, AH Plus e Sealer Plus, através de duas diferentes metodologias. 1. Teste in vivo - Avaliação histopatológica em dentes de cães. Foram utilizados 36 canais radiculares de dentes pré-molares superiores e inferiores em 2 cães, com vitalidade pulpar, os quais, após o preparo biomecânico coadjuvado pela irrigação/aspiração e inundação com solução de hipoclorito de sódio a 1 percento (Líquido de Dakin), foram obturados pela técnica clássica complementada pela condensação lateral ativa, empregando os cimentos Sealer Plus (Grupo I) e AH Plus (Grupo II). Decorridos 90 dias após a obturação, os animais foram sacrificados por sobredose anestésica, as maxilas e mandíbulas removidas e fixadas em formol a 10 percento, durante 48 horas. Após processamento histológico de rotina, os cortes foram corados pela hematoxilina e eosina, pelo tricrômico de Mallory e Brown e Brenn. A análise histopatológica evidenciou que o cimento AH Plus, quanto à compatibilidade biológica, mostrou-se superior ao Sealer...