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Article in English | LILACS-Express | LILACS | ID: biblio-1385888


ABSTRACT: This study aims to demonstrate, through a clinical case report, the applicability of the use of microtomography (µCT) in the histopathological evaluation of a ranula lesion on the oral floor and to evaluate the use of 2 % elemental iodine solution as a contrast agent, in order to obtain a better contrast effect in a tissue sample, thus facilitating the identificat ion of anatomical structures, the histomorphological evaluation and the potential use of µCT in the imaging diagnosis of lesions. Different parameters were evaluated for obtaining images in SkyScan 1172, in a biopsied piece, when impregnated in a 10 % formalin solution and in a 2 % elemental iodine solution, when impregnated for 24h and 48h. Contrast agent impregnation was evaluated using the Hounsfield unit. The use of µCT allowed the identification of sialoliths dispersed inside the biopsy specimen, while the impregnation with Elemental iodine 2 % for 24h resulted in a better contrast when compared to the other conditions. The use of the Hounsfield unit allowed an adequate evaluation of the contrast obtained when the different parameters of impregnation and image acquisition were applied. The comparison between the 3D images with and without a specific marker highlighted a better evidencing of the soft tissues, with an improvement in the contrast of the images, also allowing the ident ification of the glandular duct obstructed by the sialoliths, allowing a conclusive histopathological evaluation of the biopsied lesion.

RESUMEN: Este estudio tiene como objetivo demostrar, a través de un reporte de caso clínico, la aplicabilidad del uso de la microtomografía (µCT) en la evaluación histopatológica de una lesión de ránula en el piso de la cavidad oral y evaluar el uso de solución de yodo elemental al 2 % como agente de contraste, con el fin de obtener un mejor efecto de contraste en una muestra de tejido, facilitando así la identificación de estructuras anatómicas, la evaluación histomorfológica y el potencial uso de µCT en el diagnóstico por imágenes de lesiones. Se evaluaron diferentes parámetros para la obtención de imágenes en SkyScan 1172, en una pieza biopsiada, cuando se impregna en una solución de formalina al 10 % y en una solución de yodo elemental al 2 %, durante 24 h y 48 h. La impregnación del agente de contraste se evaluó utilizando la unidad Hounsfield. El uso de µCT permitió la identificación de sialolitos dispersos dentro de la muestra de la biopsia, mientras que la impregnación con Yodo Elemental al 2 % durante 24 h resultó en un mejor contraste en comparación con las otras condiciones. El uso de la unidad Hounsfield permitió una adecuada evaluación del contraste obtenido cuando se aplicaron los diferentes parámetros de impregnación y adquisición de imágenes. La comparación entre las imágenes 3D con y sin marcador específico destacó una mejor evidenciación de los tejidos blandos, con una mejora en el contraste de las imágenes, permitiendo además identificar el conducto glandular obstruido por los sialolitos, permitiendo una evaluación histopatológica concluyente de la lesión sometida a biopsia.

Chinese Journal of Orthopaedics ; (12): 482-491, 2022.
Article in Chinese | WPRIM | ID: wpr-932857


Objective:To study the method of intravascular angiography in vivo, analyze the clinical significance, and supply the basis of diagnosis and treatment of related orthopaedic diseases.Methods:The development was realized by improving the developer to increase the local concentration. Based on the study of Lijianmin-Chengkun Complexes and using the theory of magnetic microspheres, Fe 3O 4 magnetic microspheres with amino (negatively charged) shell are used to adsorb the aggregated ionic developer meglumine diatrizoate (positively charged diatrizoate). That is, by improving the method of developer, the magnetic microspheres can carry the developer to make new nanoparticles magnetic imaging composite particles. Under the action of external magnetic field, the magnetic imaging composite particles brought by blood circulation continue to stay and gather in the blood vessels in the magnetic field area, and the developer carried by the magnetic microspheres in the blood vessels in the magnetic field area is concentrated to reach the imaging concentration, so as to realize in vivo intravascular vascular imaging. By adjusting the ratio of the two reagents, the charge can be neutralized and condensed into small groups to improve the development efficiency. Thus, the electron microscope experiment, CT in vivo experiment, rabbit imaging experiment, experimental rabbit tissue picture confirmation, CT in vivo human body (the author is a volunteer) imaging experiment were carried out step by step. Results:Electron microscope experiment: meglumine diatrizoate, scanning electron microscope, the particle diameter is about 20 nm. Scanning electron microscope showed that the diameter of the magnetic microspheres was about 100 nm and the distribution was uniform. After the two reagents are mixed in a certain proportion, the neutralizing charge condenses into small groups, but it still has magnetohydrodynamic properties and strong paramagnetism. In vivo rabbit imaging experiment: the ideal intraosseous vascular imaging of the proximal tibia was captured. The tissue pictures of experimental rabbits confirmed that the distribution of Fe 3O 4 was obviously visible in the blood vessels in the proximal tibia on the side with magnetic field, but not on the side without magnetic field. In vivo human imaging experiment: the ideal intraosseous vascular imaging of the proximal fibula was captured. Conclusion:Through the preparation of new reagent of magnetic imaging composite particles (magnetic microspheres + meglumine diatrizoate), the concentration of in vivo bone developer can be achieved under the action of external magnetic field, and the in vivo external diameter ≥ 0.5mm can be achieved under CT thin-layer scanning.

Braz. oral res. (Online) ; 36: e085, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1384205


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.

Braz. oral res. (Online) ; 36: e053, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1374749


Abstract: This study assessed the ability of XP-endo Finisher R (FKG, La Chaux-de-Fonds, Switzerland) to remove filling remnants from curved mesiobuccal canals of maxillary molars, using the passive ultrasonic irrigation (PUI) technique as a comparison. Twenty-four curved main mesiobuccal canals (MB1) of maxillary molars were instrumented with Wave One (#25/07) and filled with gutta-percha points and AH Plus Sealer. Samples were then re-treated with a standardized protocol with Wave One (#35/06) as the master apical file. Micro-CT scans measured baseline volume of remaining filling material (in mm3). Samples were divided into two groups (n = 12) according to the supplementary cleaning approach: (PUI) or XP-endo Finisher R. Statistics compared baseline and final volume of filling material (within-group); and the percentage of filling material reduction (between-group). Mean baseline volumes, final volumes, and percentages of reduction (%) of filling material for XP-endo Finisher R and PUI were respectively: 0.060 mm3, 0.042 mm3, and 31.28%; and 0.064 mm3, 0.054 mm3, and 16.57%. Both tested protocols reduced the amount of filling material (p < 0.05). XP-endo Finisher R had higher percentage of reduction as compared to PUI (p < 0.05). XP-endo Finisher R and PUI used as supplementary cleaning protocols during re-treatment improved the removal of root filling material in curved canals; but XP-endo Finisher R was approximately twice more efficient. The complete filling material removal during re-treatment procedures is still a challenge. Supplementary cleaning protocols may help to remove the remaining material after the complete mechanical preparation of curved canals. XP-endo Finisher R was approximately twice more efficient than PUI.

Braz. oral res. (Online) ; 36: e005, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1355927


Abstract This study evaluate the maxillary anterior teeth anatomy by micro-computed tomography (μCT), about relevant characteristic for endodontic treatment planning. Fifty maxillary central incisors (MCI), lateral incisors (MLI) and maxillary canines (MC) were scanned using a μCT device. Two and three-dimensional parameters at 1 to 5mm distance to the apical foramen, external anatomic characteristics of the teeth and qualitative analysis of the internal anatomy was performed. The roundness and form factor values revealed a circular canal in the apical third in the MCI and MC, whereas MLI showed flattening in the apical third. The linear regression test indicated a progressive increase in the major/minor diameters in the five mm assessed (p < 0.001). The 3D analysis revealed the greatest volume and surface area in MC. The SMI showed a cylindrical geometry of root canals. All teeth presented Vertucci's type I root canal configuration. A mild curvature was prevalent in the MCI (45%) and a moderate one in the MLI (50%) and MC (50%). Palatal shoulder volume was smaller in the MLI (11.46 ± 3.09) than in the MCI (14.15 ± 3.85) and MC (13.95 ± 2.55). The most common exit of main apical foramen was in a central (22%), distolingual (30%) and mesiobuccal position (28%) for MCI, MLI and MC, respectively. Radicular grooves were observed in 2% of MCI and 4% of MLI. Two and three-dimensional data obtained by μCT allowed to observe morphological characteristics of internal/external anatomy of the maxillary anterior teeth. These characteristics may affect the endodontic treatment planning.

Pesqui. bras. odontopediatria clín. integr ; 22: e210112, 2022. tab, graf
Article in English | LILACS, BBO | ID: biblio-1386810


Abstract Objective: To evaluate the efficacy of silver diamine fluoride (SDF) in arresting dentin caries lesions when applied under different concentrations and times. Material and Methods: Forty-two bovine blocks were selected and fixed in 24-well plates. Each well received a mixed bacterial inoculum added to the culture medium with 5% sucrose. The plates were incubated in microaerophilia (7 days) for caries formation, confirmed by micro-CT (M1). SDF was applied over the carious lesions for different times and concentrations (n=6): SDF 30% - immediate removal, 1 minute and 3 minutes; SDF 38%, - immediate removal, 1 minute and 3 minutes. The group without treatment was the control. Then, the samples were again scanned by micro-CT (M2) and submitted to a second cariogenic challenge for 21 days. Then, a final scan was performed (M3). Results: Mean pH at the culture medium and lesion depth were compared using Kruskal-Wallis and Wilcoxon tests. 38% SDF showed the lowest metabolic activity of the biofilm. All 38% groups and 30% 1 and 3 minutes did not show an increase in mean lesion depth comparing M3 with M1. However, only 30% 3 minutes and 38% 1 and 3 minutes showed a significant reduction of lesion depth. Conclusion: The minimum application time of 30% SDF to arrest dentin caries lesion was 1 minute, while 38% SDF arrested with application and immediate removal.

Animals , Cattle , Tooth Remineralization , Cariostatic Agents/therapeutic use , Dental Caries/epidemiology , Dentin , Diamines/chemistry , Fluorides/chemistry , Silver/therapeutic use , In Vitro Techniques/methods , Longitudinal Studies , Statistics, Nonparametric , Biofilms , X-Ray Microtomography/instrumentation
Braz. oral res. (Online) ; 36: e042, 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1364601


Abstract: Although the effects of different intraoral scanners, model scanners, and CAM units on the marginal and internal fitting of restorations have been investigated, the effects of CAD software in particular has not been evaluated. The marginal and internal fit of indirect restorations may vary according to the CAD software used, even when using the same intraoral scanner and milling machine. The purpose of this study was to evaluate the marginal and internal fit of milled full ceramic crowns designed with three different CAD systems. Eleven typodont maxillary first premolar teeth were prepared and scanned using a 3Shape TRIOS Intraoral Dental Scanner. The obtained STL scan data were exported and used to design a full crown using three different CAD systems (CEREC, KaVo, and Planmeca). An independent milling unit was used to manufacture the crowns for each group (n = 11). The marginal and internal fit were evaluated for each restoration using 2D and 3D micro-CT analysis. For 2D analysis, 18 measurements for each sample were made, covering the marginal (Marginal Gap Buccal (MG-A), Marginal Gap Palatinal (MG-B), Finish Line Buccal (FL-A), Finish Line Palatinal (FA-B)) and internal fit locations (Axial Wall Buccal (AW-A), Axial Wall Palatinal (AW-B), Lingual Cusp (LC), Buccal Cusp (BC), and Occlusal Central Fossa (OCF)). Statistical analyses were performed using Open Source R Statistical Software (α = 0.05) The results of Duncan's multiple range test showed that the values for the marginal measurement points MG-A, MG-B, FL-A, and FL-B in the Planmeca group were significantly higher than the values obtained in the CEREC and KaVo groups (p < 0.05). In AW1, values of the CEREC group were found to be higher than those of the KaVo and Planmeca groups (p < 0.05). CAD software showed an effect on the marginal fit values of crowns whereas no significant difference was observed in terms of the internal fit, except for a single measurement point made from the buccal direction.

Braz. j. oral sci ; 20: e210432, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254269


Aim: The aim of this study was to evaluate, by micro-computed tomography (micro-CT) analysis, the remaining filling material during endodontic retreatment performed with Protaper retreatment without solvent. Methods: Forty mandibular molars were divided into two groups (n = 20) according to the sealer used in the obturation: the bioceramic TotalFill BC (TF) or the resin-based AH Plus (AHP). The specimens were scanned before instrumentation, after obturation and after filling removal. Only the mesial roots were analysed. The filling volumes and the remaining filling material were calculated in the entire root canal and in the cervical, middle and apical thirds. Results: The volume of obturation and the volume of remaining filling material in the entire root canal and in the cervical, middle and apical thirds of the canal between the groups were not statistically different (independent t-test, p > 0.05). In the AHP group, there was a higher percentage of remaining filling material in the middle third than in the cervical third (p < 0.05). Conclusion: The filling material could not be entirely removed from any specimen

Root Canal Filling Materials , Retreatment , X-Ray Microtomography , Molar
Acta odontol. latinoam ; 34(1): 50-55, Apr. 2021. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1284934


ABSTRACT Dental anatomy can vary significantly between different populations from different countries. Dental anatomical variations are of great interest to the dental professional, especially to endodontists, since they can influence the outcome of endodontic treatment. The purpose of the present study was to describe the anatomical variations of the root canal in mandibular first premolars in a populationfrom Colombia, using micro-computed tomography. Fifty mandibular first premolars were scanned on a SkyScan 1174 and the microcomputed tomographic images were reconstructed. Anatomy was assessed using three-dimensional models. The parameters used were: Vertucci's classification, area and volume, perimeter, circularity, and major and minor diameter at 1, 2 and 3 mm from the apical foramen. According to the Vertucci's classification, teeth were classified as: types I (40%), V (24%), VII (4%) and III (4%), with 28% not classifiable. C-shaped canals were found in 1.8% of the sample. Mean evaluations at 1, 2, 3 mm of the foramen were as follows, respectively: perimeter 1.07 ± 0.57, 1.27 ± 0.78 and 1.57 ± 0.84 mm; circularity 0.59 ± 0.19, 0.57 ± 0.20 and 0.56 ± 0.22; maximum diameter 0.41 ± 0.23, 0.48 ± 0.33 and 0.60 ± 0.37 mm; minimum diameter 0.24 ± 0.10, 0.26 ± 0.11 and 0.21 ± 0.13 mm. Mean total area and volume were 61.27 ± 16.47 mm2 and 12.47 ± 4.95 mm3, respectively. There was wide anatomical variation in mandibular first premolars from Colombian individuals, reinforcing the need for proper anatomical knowledge to establish more effective strategies for endodontic treatment.

RESUMO A anatomia dentària pode variar significativamente entre diferentes populagoes, de diferentes países. As variagoes anatómicas dentais sao de grande interesse para o profissionai da odontologia, principalmente para os endodontistas, pois podem influenciar no resultado do tratamento endodóntico. Descrever as variagoes anatómicas do canal radicular dos primeiros pré-molares inferiores em uma populagao da Colómbia, usando a micro tomografia computadorizada. Cinquenta primeiros pré-molares inferiores foram digitalizados em um SkyScan 1174 e as imagens tomográficas foram reconstruidas e a anatomia foi avaliada por meio de modelos tridimensionais. Os parámetros utilizados foram: classificagao de Vertucci, área e volume, perímetro, circularidade e diámetros maior e menor a 1, 2 e 3 mm do forame apical. De acordo com a classificagao de Vertucci, os dentes foram classificados em: tipos I (40%), V (24%), VII (4%) e III (4%), sendo 28% nao classificáveis. Canais em forma de C foram encontrados em 1,8% da amostra. As avaliaçoes médias em 1, 2, 3 mm do forame foram as seguintes, respectivamente: perímetro 1,07 ± 0,57, 1,27 ± 0,78 e 1,57 ± 0,84 mm; circularidade 0,59 ± 0,19, 0,57 ± 0,20 e 0,56 ± 0,22; diámetro maior 0,41 ± 0,23, 0,48 ± 0,33 e 0,60 ± 0,37 mm; diámetro menor 0,24 ± 0,10, 0,26 ± 0,11 e 0,21 ± 0,13 mm. A média da área total e do volume foram 61,27 ± 16,47 mm2 e 12,47 ± 4,95 mm3, respectivamente. Houve uma grande variaçâo anatómica nos primeiros pré-molares inferiores de colombianos, reforçando a necessidade de conhecimento anatómico adequado para estabelecer estratégias mais eficazes para o tratamento endodóntico.

Dent. press endod ; 11(1): 72-77, Jan-Apr2021. Tab, Ilus
Article in English | LILACS | ID: biblio-1348251


Introdução: O tipo de agulha e fluxo de irrigação é importante para a limpeza adequada no terço apical do canal radicular. Objetivo: Avaliar a influência do tipo de agulha e fluxo de irrigação na limpeza do canal radicular e canais laterais simulados e na extrusão apical do irrigante. Métodos: Trinta e dois dentes de resina foram utiliza- dos. Após a instrumentação do canal radicular, foram feitos quatro canais laterais a 2 e 7 mm do ápice. Os canais radiculares foram preenchidos com solução de contraste. Os canais foram irrigados com dois tipos de agulha, 29G e 31G, com diferentes designs (abertura lateral e apical) e dois fluxos (2 ou 5 mL/min), a 1 mm aquém do comprimento de trabalho. O volume da solução de contraste nos canais principal e laterais após irrigação e a extrusão apical do irrigante (mm3 ) foi avaliado por micro-CT, em comparação com a análise inicial. Os dados em porcentagem foram analisados pelos testes ANOVA e Tukey (α=0,05). Resultados: não houve diferença entre os protocolos de irrigação para limpeza da solução de contraste. Maior volume de extrusão apical com agulha 29G com abertura apical e 5 mL/min foi observado, em comparação ao mesmo tipo de agulha e 2 mL/min (p<0,05). Conclusão: Todos os protocolos de irrigação foram associados à limpeza dos canais radiculares. Maior extrusão apical foi observada com agulha 29G ­ abertura apical com maior fluxo de irrigação (5 mL/min). Implicações clínicas: Irrigação endodôntica com agulha com abertura apical e maior fluxo da solução pode favorecer a extrusão dos irrigantes para os tecidos periapicais (AU).

Introduction: needle and irrigation flow rate are important for proper cleaning of the root canal. Aim: to evaluate the influence of type of needle and irrigation flow rate on cleaning of root canal and simulated lateral canals and the apical extrusion of irrigant. Methods: Thirty-two resin teeth were used. After root canal instrumentation, four lateral canals were made at 2 and 7 mm from the apex. Root canals were filled with contrast solution. The root canals were irrigated with two types of needle, 29G and 31G, with different designs (side and apical opening) and two flow rates (2 or 5 mL/min), at 1 mm short of the working length. The volume of the contrast solution in the main and lateral canals after irrigation and apical extrusion of the irrigant (mm3) were evaluated by Micro-CT, in comparison with the initial analysis. Data in percentage were analyzed by ANOVA and Tukeys tests (α = 0.05). Results: no difference among the irrigation protocols for contrast solution cleaning was observed. Higher volume of apical extrusion using needle 29G-apical opening and 5 mL/min in comparison with the same type of needle and 2 mL/min was observed (p < 0.05). Conclusion: all irrigation protocols were associated with root canals cleaning. Greater apical extrusion was observed for needle 29G-apical opening with higher irrigation flow rate (5 mL/min). Clinical implications: endodontic irrigation using a needle with apical opening and higher flow rate of solution may favor extrusion of irrigant to the periapical tissues (AU).

Periapical Tissue , Root Canal Irrigants , X-Ray Microtomography , Needles , Dental Pulp Cavity , Household Work
Braz. dent. j ; 32(1): 42-47, Jan.-Feb. 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1180727


Abstract New methodologies using micro-CT to evaluate solubility besides dimensional and morphological changes of endodontic materials are proposed. However, there is no standardization in the methods. The aim of this study was to assess the effect of different dimensions of test samples on volumetric change evaluation of different endodontic materials. AH Plus, FillCanal and Sealapex root canal sealers, Biodentine, IRM and MTA root-end filling cements were used in the tests. Samples of each material with a thickness of 1.5 mm and different diameters were manufactured: 6.3, 7.75, and 9.0 mm. The samples were scanned in micro-computed tomography (micro-CT) after setting and after 7 days of immersion in distilled water. The volumetric change was evaluated by means of the difference in the total volume of the specimens before and after immersion. Data were submitted to ANOVA and Tukey tests (p<0.05). The size of the samples did not affect the percentage of volumetric change of the materials (p>0.05). All sample sizes had greater volume loss for Sealapex among the sealers and Biodentine for the cements (p<0.05). In conclusion, Biodentine and Sealapex had the highest volume loss after immersion. Samples with 1.5 mm thickness, and diameters ranging between 6.3 and 9.0 mm can be used to assess the stability of endodontic materials using micro-CT without affecting the percentage of volumetric change.

Resumo Novas metodologias utilizando micro-CT são propostas para avaliar a solubilidade além de alterações dimensionais e morfológicas em materiais endodônticos. No entanto, não há padronização nos métodos. O objetivo deste estudo foi avaliar o efeito de diferentes dimensões de corpos de prova na avaliação da alteração volumétrica de diferentes materiais endodônticos. Os cimentos obturadores AH Plus, FillCanal e Sealapex e os cimentos retrobturadores Biodentine, IRM e MTA foram utilizados nos testes. Foram confeccionadas amostras de cada material com espessura de 1.5 mm e diâmetros diferentes: 6.3, 7.75 e 9.0 mm. As amostras foram escaneadas em microtomografia computadorizada (micro-CT) após a presa e após 7 dias de imersão em água destilada. A alteração volumétrica foi avaliada por meio da diferença no volume total dos corpos de prova antes e após a imersão. Os dados foram submetidos aos testes ANOVA e Tukey (p<0,05). A dimensão das amostras não afetou o percentual de alteração volumétrica dos materiais (p>0,05). Todos os diâmetros de amostra mostraram maior perda de volume para Sealapex entre os cimentos obturadores e Biodentine entre os cimentos retrobturadores (p<0,05). Como conclusão, Biodentine e Sealapex mostraram a maior perda volumétrica após a imersão. Amostras com 1.5 mm de espessura e diâmetros variando entre 6.3 e 9.0 mm podem ser usadas para avaliação da estabilidade de materiais endodônticos utilizando micro-CT, sem influenciar no percentual de alteração volumétrica.

Root Canal Filling Materials , Oxides , Root Canal Obturation , Materials Testing , Calcium Compounds , Drug Combinations , Epoxy Resins , X-Ray Microtomography
Braz. oral res. (Online) ; 35: e008, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132748


Abstract: The aim of this study was to assess the influence of micro-computed tomography (micro-CT) voxel size on the evaluation of debris accumulation after passive ultrasonic irrigation (PUI) in curved root canals prepared with rotary nickel-titanium files. Mesial root canals (n = 24) of mandibular molars with curvature between 25° and 35° were prepared using ProDesign Logic 30/.05 (PDL) or HyFlex EDM 25/.08 (HEDM). PUI was performed after root canal preparation of all root canals. The specimens were scanned using high-resolution (5 μm voxel size) micro-CT imaging before and after experimental procedures. The percentage of debris was analyzed in the middle and apical thirds using images with 5, 10 and 20 μm voxel sizes. Data were compared using unpaired and paired Student's t-test, ANOVA and Tukey's statistical tests (α = 0.05). There were no differences among the debris analyses performed at different voxel sizes (5, 10 and 20 μm) (p > 0.05). The percentage of debris was similar between the root canals prepared by PDL and HEDM before and after PUI (p > 0.05). In both groups, the percentage of debris decreased in the middle third after PUI (p < 0.05). Within the limitations of this ex vivo study, it can be concluded that the voxel sizes evaluated did not have a significant impact on the analysis of accumulated debris. However, the results showed a tendency for detection of more debris in the analysis performed using a lower voxel size. PUI decreased the debris accumulation in the middle third of curved root canals.

Humans , Root Canal Preparation , Dental Pulp Cavity/diagnostic imaging , X-Ray Microtomography , Molar/diagnostic imaging
Braz. dent. sci ; 24(1): 1-8, 2021. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1145442


Objetivo: Estudos demostraram que a zircônia monolítica um dos materiais restauradores desenvolvidos recentemente, resolveu vários problemas de restauração de zircônia. Portanto, a precisão marginal e o ajuste interno são necessários para o sucesso clinico e para a qualidade da restauração, e o espaço do cimento pode influenciar o ajuste marginal. Assim, o presente estudo teve como objetivo investigar os efeitos da espessura do cimento e o tipo de restauração na discrepância marginal. Material e métodos: foram usadas para fabricação de coroa total. Dois tipos de materiais incluindo Zirconia monolítica (Zolid) e Sintron foram usadas para produzir a coroa total. As amostras de cada grupo foram digitalizadas em laboratório dentário por um scanner 3D, projetadas e acessadas usando CAD-CAM. As amostras foram divididas em quatro grupos de cinco com espaço de 30 e 50 mícrons de cimento. Para avaliar a discrepância marginal, as coroas foram colocadas em seus respectivos dentes sem o uso de qualquer intermediário e examinados em micro-CT. Os dados foram avaliados pelo software SPSS. Resultados: Descobriu-se que a discrepância marginal do Sintron é maior que a discrepância da zircônia monolítica. Na verdade, a zircônia monolítica com espaço de 50 µm de cimento exibiu uma menor discrepância marginal, e o espaço de cimento do Sintron não influenciou significantemente na discrepância marginal. Conclusão: Concluiu-se que os tipos de material e o espaço do cimento influencia na discrepância marginal da restauração construída pelo fluxo digital (AU)

Objective: Studies demonstrated that as one of then ewly developed restorative materials, monolithic zirconia resolved several issues of zirconia restoration. Therefore, marginal accuracy and internal fit are necessary for clinical success and quality of restorations, and cement space may influence the marginal fit. Thus, the present research aimed to investigate the effects of the cement thickness and kind of restoration on the marginal discrepancy. Material and methods: In this study, 20 maxillary left first molars, prepared by DRSK Co., were used to fabricate a full crown. Two types of material included monolithic zirconia (Zolid) and Sintron were used to make a full crown. Samples from each group were scanned by dental laboratory 3D scanner and designed and processed using CAD-CAM. The samples were divided into four groups of five with 30-and 50- µm cement spaces. In order to assess the vertical marginal discrepancy, the crowns were fittedon their respective teeth without using any mediator and examined by a micro-CT scanner. Data were analyzed by SPSS software. Results: It has been found that marginal discrepancy in Sintron is higher than the discrepancy of monolithic zirconia. In fact, monolithic zirconia with 50-micron cement space exhibited the least marginal discrepancy and the cement space in Sintron did not significantly influence the marginal discrepancy. Conclusion: It has been concluded that the material kinds and cement space influence the restoration marginal discrepancy constructed by digital workflow (AU)

Dental Marginal Adaptation , Dental Cements , X-Ray Microtomography
Braz. oral res. (Online) ; 35: e060, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1249378


Abstract: This study aimed to describe the morphometric relationship of root canal orifices on the pulp floor in the presence/absence of mesiobuccal second canal (MB2) in the maxillary first molars and other aspects of its internal anatomy. Sixty-two maxillary first molars were scanned by micro-CT. The presence of the MB2 canal was verified. The distance between the center points of the MB1, MB2, distobuccal (DB), and palatal (P) canal orifices on the pulp floor were measured (MB1-MB2, MB1-DB, MB2-DB, MB1-P, and DB-P). The MB1-P to DB-P ratio was calculated. The distances between the anatomic apex and the MB1 and MB2 apical foramina were measured. The length of the band-shaped isthmus was also measured. Student's t-test was applied to verify the association between the presence of an MB2 canal, the interorifice distances, and the ratio of the MB1-P to DB-P distance (α = 5%). The MB2 canal was present in 43 roots (69.35%). Statistics showed significant differences when MB2 was present for the largest MB1-P distance (p < 0.05) and higher values for the MB1-P to DB-P ratio (p < 0.05). A band-shaped isthmus was detected in 25.8% of MB roots. The mean distance from the apical foramen to the isthmus floor ranged from 1.74 for MB1 canals to 1.42 for MB2 canals. Canal orifice distances on the pulp floor may predict the presence of MB2 canals. There was a high incidence of isthmus, accessory canals, and apical delta in the critical apical zone in MB roots of maxillary first molars.

Tooth Root/diagnostic imaging , Maxilla/diagnostic imaging , Dental Pulp Cavity/diagnostic imaging , X-Ray Microtomography , Molar/diagnostic imaging
Braz. oral res. (Online) ; 35: e028, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1153621


Abstract The aim of this study was to evaluate the filling ability of a new ready-to-use calcium silicate-based sealer using thermoplastic or single-cone technique in flattened root canals. Twenty-four flattened distal canals of mandibular molars with a buccolingual diameter 4 or more times larger than the mesiodistal diameter were selected. The root canals were prepared and filled (n = 12), according to the following techniques: thermoplastic or single-cone technique using Bio-C Sealer. The teeth were scanned using Skycan 1176 micro-computed tomography (micro-CT) - voxel size 8.74 µm, before and after filling the root canal. The percentage of voids in the filled root canals was evaluated, and the data were statistically analyzed using the unpaired t-test (α = 0.05). The root canals filled using the thermoplastic technique created a smaller percentage of voids in the cervical/middle thirds than those filled using the single-cone technique (p < 0.05). There was no difference in the percentage of voids using either technique in the apical third (p > 0.05). The flattened root canals in the cervical/middle thirds were better filled using the ready-to-use calcium silicate-based sealer associated to the thermoplastic technique, compared with the single-cone technique. In the apical third, the techniques showed similar filling ability.

Root Canal Filling Materials , Dental Pulp Cavity/diagnostic imaging , Root Canal Obturation , Root Canal Preparation , X-Ray Microtomography , Gutta-Percha , Molar
Acta odontol. latinoam ; 34(3): 282-288, 2021. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1383415


ABSTRACT This study compared the shaping ability of single-file reciprocating (WaveOne Gold) and multifile rotary (Mtwo) systems on mandibular oval-shaped canine root canals, using microcomputed tomography (micro-CT). Thirty mandibular canines were scanned by micro-CT and assigned to one of two groups (n=15) according to the system used for root canal preparation: WaveOne Gold or Mtwo. After preparation, the teeth were rescanned, and the percentage of untouched canal area, apical transportation and centering ability were analyzed. The data was evaluated using Kruskal and Mann- Whitney tests (p<0.05). No difference was found in percentage of unprepared canal area between groups in the entire root canal or the apical third, or in centering ability (p>0.05). WaveOne gold had less canal transportation than MTwo at the 5 mm section (p<0.05). WOG and Mtwo systems presented similar shaping ability and centering ability in oval-shaped canals. However, WOG presented less transportation than Mtwo at 5 mm from the apex.

RESUMO Este estudo comparou a capacidade de modelagem dos sistemas reciprocante de lima única (WaveOne Gold) e rotatórios com múltiplas limas (Mtwo) em caninos ovais inferiores, usando microtomografia computadorizada (micro-CT). Trinta caninos inferiores foram escaneados por micro-CT e divididos em dois grupos (n = 15) de acordo com o sistema usado durante o preparo do canal radicular: WaveOne Gold (WOG) e Mtwo. Os dentes foram reeescaneados e a porcentagem de área do canal não preparada, transporte apical e capacidade de centralização foram analisados. Os dados foram avaliados pelos testes de Kruskal Wallis e Mann-Whitney (p<0,05). Nenhuma diferença foi encontrada na porcentagem de área não preparada entre os grupos em todo o canal radicular e no terço apical e na capacidade de centralização (p>0,05). O sistema WOG promoveu menor transporte do canal do que o sistema Mtwo na região de 5mm aquém do ápice (p<0,05). Os sistemas WOG e Mtwo apresentaram capacidade de modelagem e capacidade de centralização semelhantes em canais ovais. No entanto, WOG promoveu menor transporte do que Mtwo a 5 mm do ápice.

Dent. press endod ; 10(3): 49-55, Sept-Dec.2020. Tab, Ilus
Article in English | LILACS | ID: biblio-1344785


Objetivo: O presente estudo usou micro-CT para avaliar a quantidade de material obturador remanescente em canais radiculares curvos que tinham sido obturados com cimento Endosequence BC/Cpoint ou com cimento AH/ guta-percha, depois do retratamento utilizando instrumentos rotatórios ou reciprocantes. Métodos: Sessenta canais mesiovestibulares de molares superiores foram instrumentados até MTwo #35.04. As amostras foram randomicamente alocadas em quatro grupos (n=15): os canais do G1 e G2 foram obturados com AH/guta-percha, e os canais do G3 e G4 foram obturados com BC/Cpoint. O material obturador foi removido usando instrumentos rotatórios ou reciprocantes ­ G1 e G3: R25 Reciproc + reinstrumentação com R40; e G2 e G4: Sistema ProTaper Universal Retratamento + reinstrumentação com MTwo 40.06. Micro-CTs foram usadas para medir a quantidade de material obturador remanescente (mm3 ) para o canal inteiro e para cada terço, em dois momentos: 1) após a remoção do material obturador; e 2) após a reinstrumentação. Resultados: Após a remoção do material obturador, BC/CPoint permaneceu mais dentro do canal do que AH/guta-percha quando o canal inteiro (29,92% x 19,25%, p=0,0290) e o terço apical foram analisados. Após a reinstrumentação, BC/CPoint permaneceu mais do que AH/guta-percha somente no terço apical. Protocolos de tratamento com instrumentos rotatórios ou reciprocantes removeram material obturador sem diferença para AH/guta-percha (G1 e G2: p> 0,05) e BC/CPoint (G3 e G4: p> 0,05). Conclusões: BC/Cpoint é mais difícil de ser removido de canais radiculares curvos do que AH/guta-percha. Instrumentos rotatórios e reciprocantes têm habilidade similar na remoção de material obturador (AU).

Objective: This study used micro-CT to evaluate the amount of remaining filling material in curved root canals obturated with Endosequence BC Sealer/Cpoint or AH/gutta-percha after a rotary or reciprocating retreatment. Methods: Sixty mesiobuccal canals of maxillary molars were instrumented up to MTwo #35.04. Samples were randomly assigned to four groups (n=15): canals from G1 and G2 were filled with AH/gutta-percha, and canals from G3 and G4 were filled with BC/Cpoint. Filling material was removed using rotary or reciprocating instruments: G1 and G3: R25 Reciproc + re-shaping with R40; and G2 and G4: ProTaper Universal Retreatment system + re-shaping with MTwo 40.06. Micro-CT was used to measure the remaining amount of filling material (mm3 ), for the whole canal, and for each third, in two moments: 1) after filling removal and 2) after canal re-shaping. Results: After filling removal, BC/CPoint remained more into the canal than AH/Gutta-percha when the whole canal (29.92% x 19.25%, p = 0.0290) and the apical third were analyzed. After re-shaping, BC/CPoint remained more than AH/Gutta-percha only in the apical third. Rotary or reciprocating retreatment protocols removed filling material without difference for AH/gutta-percha (G1 and G2: p > 0.05) and BC/CPoint (G3 and G4: p > 0.05). Conclusion: BC/Cpoint is more difficult to be removed from curved root canals than AH/gutta-percha. Reciprocating and rotary instruments have similar ability to remove filling material (AU).

Root Canal Filling Materials , Biofilms , Dental Instruments , X-Ray Microtomography , Lifting , Retreatment , Gutta-Percha , Molar
Braz. dent. j ; 31(5): 499-504, Sept.-Oct. 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132336


Abstract This study evaluated by micro-computed tomography (μCT) the filling ability in curved root canals, besides the flow of AH Plus (AHP) and Neo MTA Plus (NMTAP) sealers using different methodologies. Mandibular molars mesial roots with two root canals and degree of curvature between 20° and 40° were selected. The specimens were prepared with the ProDesign R system up to size 35.05 and were filled with the sealers by a continuous wave of condensation technique, Thermo Pack II (n=12). The teeth were scanned using μCT after root canal preparation and obturation. The volumetric percentage of filling material and voids were calculated. Flow was evaluated based on ISO 6876/2012 (n=10). Flow and filling were also evaluated in μCT using a glass plate with a central cavity and four grooves from the central cavity (n=6). Flow was linearly calculated into the grooves. The central cavity filling (CCF) and lateral cavity filling (LCF) were calculated in mm³. Data were submitted to non-paired t test with a significance threshold at 5%. The percentage of filling and voids between the root canals filled with AHP or NMTAP was similar (p>0.05). NMTAP presented the lowest flow in conventional test (p<0.05). Using μCT, sealers had similar CCF, LCF and linear flow (p>0.05). In conclusion, NMTAP and AHP had similar filling ability in curved mesial root canals of mandibular molars without presence of isthmus. Although AHP presented better flow than NMTAP using ISO methodology, there was no difference between these materials regarding volumetric filling when evaluated by μCT.

Resumo Este estudo avaliou por microtomografia computadorizada (μCT) a capacidade de preenchimento de canais radiculares curvos, além do escoamento dos cimentos AH Plus (AHP) e Neo MTA Plus (NMTAP) utilizando diferentes metodologias. Foram selecionadas raízes mesiais de molares inferiores com dois canais radiculares e grau de curvatura entre 20° e 40°. As amostras foram preparadas com o sistema ProDesign R até o tamanho 35.05 e foram obturadas com os cimentos por uma técnica de onda contínua de condensação, Thermo Pack II (n=12). Os dentes foram escaneados usando μCT após o preparo e obturação do canal radicular. A porcentagem volumétrica de material de preenchimento e vazios foram calculados. O escoamento foi avaliado com base na norma ISO 6876/2012 (n=10). O escoamento e o preenchimento também foram avaliados em μCT usando uma placa de vidro com uma cavidade central e quatro canaletas a partir da cavidade central (n=6). O escoamento foi calculado linearmente nas canaletas. O preenchimento da cavidade central (PCC) e o preenchimento da cavidade lateral (PCL) foram calculados em mm³. Os dados foram submetidos ao teste t não pareado com nível de significância de 5%. A porcentagem de preenchimento e vazios entre os canais radiculares preenchidos com AHP ou NMTAP foi semelhante (p>0,05). NMTAP apresentou o menor escoamento no teste convencional (p<0,05). Utilizando μCT, os cimentos apresentaram PCC, PCL e escoamento linear semelhantes (p>0,05). Em conclusão, NMTAP e AHP apresentaram capacidade de preenchimento semelhante em canais mesiais curvos de molares inferiores sem presença de istmo. Embora o AHP tenha apresentado melhor escoamento que o NMTAP usando a metodologia ISO, não houve diferença entre esses materiais em relação ao preenchimento volumétrico quando avaliados por μCT.

Root Canal Filling Materials , Dental Pulp Cavity/diagnostic imaging , Root Canal Obturation , Root Canal Preparation , X-Ray Microtomography , Gutta-Percha
Braz. dent. j ; 31(5): 505-510, Sept.-Oct. 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132327


Abstract The present study used microcomputed tomography (micro-CT) images to assess the prevalence, number, and location of apical ramifications (ARs) in the root canals of different dental groups in a Brazilian population. Three hundred and sixty-seven extracted human teeth, totaling 475 roots, were scanned by micro-CT at 19.6 µm spatial resolution. The obtained images were evaluated by two observers in consensus, and a descriptive analysis was performed to verify the prevalence, number, and location of ARs in each dental group. Chi-square test was used to compare the prevalence of ARs in different types of roots, and one-way analysis of variance compared the number of ARs in the apical 1 mm, 2 mm, and 3 mm of the root. Significance level was established at 5% (α=0.05). ARs were present in 253 (53.3%) of the 475 roots evaluated. A total of 607 ARs were detected, with the vast majority (530) located at one and two millimeters from the main foramen. The highest prevalence of ARs was observed in maxillary canines (65%); maxillary premolars - single-rooted (83.3%), buccal root (80%), and palatine root (73.3%); mandibular premolars (64.2%); mesiobuccal root of maxillary molars (76.6%); and mesial root of mandibular molars (66.6%). For the Brazilian population, most of the ARs are located in the apical 1 and 2 mm of the root, with greater prevalence in the posterior teeth and maxillary canines. These findings suggest the need for additional attention while planning endodontic treatments, including strategies to effectively clean and fill the apical region.

Resumo O presente estudo utilizou imagens de microtomografia computadorizada (MicroCT) para avaliar a prevalência, número e localização de ramificações apicais (RAs) dos canais radiculares de diferentes grupos dentários em uma população brasileira. Trezentos e sessenta e sete dentes humanos extraídos (totalizando 475 raízes) foram escaneados em um aparelho de MicroCT, com uma resolução espacial de 19,6 µm. As imagens foram analisadas em consenso por dois avaliadores, e uma análise descritiva foi realizada para verificar a prevalência, número e localização de RAs em cada grupo dentário. O teste Qui-quadrado foi utilizado para comparar a prevalência de RAs em diferentes tipos de raízes e a análise de variância (ANOVA - um critério) comparou o número de RAs em 1 mm, 2 mm e 3 mm apicais da raiz. O nível de significância foi estabelecido em 5% (α=0,05). As RAs estavam presentes em 253 (53,3%) das 475 raízes avaliadas. Foram detectadas 607 RAs com a maioria (530) localizada a 1 e 2 milímetros do forame principal. A mais alta prevalência de RAs foi observada nos caninos superiores (65%); pré-molares superiores - unirradiculares (83,3%), raiz vestibular (80%) e raiz palatina (73,3%); pré-molares inferiores (64,2%); raiz mésio-vestibular dos molares superiores (76,6%); e raiz mesial dos molares inferiores (66,6%). Na população brasileira, a maioria dos RAs está localizada em 1 e 2 mm apicais da raiz, com maior prevalência nos dentes posteriores e nos caninos superiores. Esses achados sugerem atenção adicional ao planejar um tratamento endodôntico, bem como adoção de estratégias para uma limpeza e obturação efetiva da região apical dos dentes.

Humans , Tooth Root , Dental Pulp Cavity/diagnostic imaging , Brazil , X-Ray Microtomography , Molar
Rev. cuba. estomatol ; 57(2): e2901, abr.-jun. 2020. tab, graf
Article in Portuguese | LILACS, CUMED | ID: biblio-1126500


RESUMO Introdução: Os estudos científicos acerca das propriedades físicas e mecânicas apresentadas pelas resinas compostas são cada vez mais necessários diante da grande variedade de produtos disponíveis no mercado atual, resultante do aumento de sua demanda dentro da odontologia que preza por preparos minimamente invasivos com a devolução das características estéticas e funcionais do elemento dentário. Objetivo: Avaliar e comparar a microdureza e porosidade das resinas compostas fotopolimerizavéis Filtek Z350 XT 3M e Zirconfill Technew. Métodos: Foram confeccionados 10 corpos de prova por amostra (n= 10) submetidos a teste microdureza Vickers e porosidade por microtomografia computadorizada. Resultados: Com relação à presença de porosidades, dada em porcentagem, o grupo da Filtek apresentou os menores valores médios. Quando comparado estatisticamente, os grupos apresentaram diferença estatística (p= 0,019), com uma magnitude de efeito alta. Com relação aos valores de microdureza, o grupo da Filtek apresentou os maiores valores médios. Quando comparados estatisticamente, os grupos não apresentaram diferença estatística (p > 0,05). Conclusões: A porosidade foi significativamente diferente entre os grupos estudados, sendo o grupo Filtek Z350XT de menor percentual. No entanto, os grupos não apresentaram diferença estatística para microdureza, apesar do grupo Filtek Z350XT ter apresentado maior valor médio(AU)

RESUMEN Introducción: Los estudios científicos sobre las propiedades físicas y mecánicas presentadas por las resinas compuestas son cada vez más necesarios ante la gran variedad de productos disponibles en el mercado actual, resultante del aumento de su demanda dentro de la odontología que aprecia por preparaciones mínimamente invasivas con la devolución de las características estéticas y funcionales del elemento dental. Objetivo: Evaluar y comparar la microdureza y porosidad de las resinas compuestas fotopolimerizables Filtek Z350 XT 3M y Zirconfill Technew. Métodos: Se han confeccionado 10 cuerpos de prueba por muestra (n= 10) sometidos a prueba de microdureza Vickers y porosidad por microtomografía computarizada. Resultados: Con respecto a la presencia de porosidades, dada en porcentaje, el grupo de Filtek presentó los menores valores medios. Cuando se comparó estadísticamente, los grupos presentaron una diferencia estadística (p= 0,019), con una magnitud de efecto alto. Con respecto a los valores de microdureza, el grupo de Filtek presentó los mayores valores medios. Cuando se comparó estadísticamente, los grupos no presentaron una diferencia estadística (p> 0,05). Conclusiones: La porosidad fue significativamente diferente entre los grupos estudiados, siendo el grupo Filtek Z350XT de menor porcentaje. Sin embargo, los grupos no presentaron diferencia estadística para microdureza, a pesar de que el grupo Filtek Z350XT presentó un valor medio más alto(AU)

ABSTRACT Introduction: Scientific studies about the physical and mechanical properties of composite resins are increasingly needed in view of the wide variety of products available in the market today, resulting from the increase in their demand for dental care purposes, with a preference for minimally invasive preparations aimed at restoring the esthetic and functional characteristics of the treated element. Objective: Evaluate and compare the microhardness and porosity of the photopolymerizable composite resins Filtek Z350 XT and Zirconfill Technew. Methods: Ten test bodies were developed per sample (n= 10) and subjected to Vickers microhardness and porosity testing by computerized microtomography. Results: With respect to the presence of porosity, expressed in percentages, the Filtek group had the lowest mean values. When compared statistically, the two groups showed a statistical difference (p= 0.019) with a high effect magnitude. Regarding microhardness, the Filtek group had the highest mean values. Statistical comparison did not find any difference between the groups (p> 0.05). Conclusions: Porosity was significantly different in the groups studied, the Filtek Z350XT group exhibiting the lowest percentage. However, the groups did not show any statistical difference concerning microhardness, despite the fact that the Filtek Z350XT group had a higher mean value(AU)

Humans , Dental Care/adverse effects , Composite Resins/adverse effects , X-Ray Microtomography/methods , Hardness Tests/methods , Physical Phenomena