scholarly journals Mechanical Preparation Showed Superior Shaping Ability than Manual Technique in Primary Molars - A Micro-Computed Tomography Study

2017 ◽  
Vol 28 (4) ◽  
pp. 453-460 ◽  
Author(s):  
Lídia Regina da Costa Hidalgo ◽  
Léa Assed Bezerra da Silva ◽  
Graziela Bianchi Leoni ◽  
Jardel Francisco Mazzi-Chaves ◽  
Emily Eduardo da Silva Carvalho ◽  
...  

Abstract The aim of the study was to evaluate canal preparation in primary molars with hand files, ProTaper Next and Self-Adjusting File (SAF) by 2D and 3D micro-computed tomography (micro-CT) analysis. Canals of 24 primary molars were prepared with hand files (HF), ProTaper Next (PTN) and SAF (n=8/group). The teeth were scanned before and after root canal preparation and the pre- and postoperative micro-CT images were reconstructed. Changes in 2D (area, perimeter, roundness, minor and major diameter) and 3D [volume, surface area, structure model index (SMI)] morphological parameters, as well as canal transportation and lateral perforations were evaluated (Kruskal-Wallis and ANOVA; a=0.05). SAF presented smaller changes in minor diameter, volume and surface area compared with HF and PTN (p<0.05). PTN presented more circular canals after preparation. 3D analysis revealed greater transportation in HF. PTN and SAF presented more centered canal preparation, especially in curved areas. SAF and HF presented, respectively, the lowest (0.05±0.02 and 0.07±0.04) and highest (0.14±0.11 and 0.29±0.17) apical transportation. There were fewer lateral perforations in SAF (4.2%) and PTN (7.7%) than in HF (47.8%) (p<0.05). In primary molars, mechanical preparation showed better shaping ability than hand files, promoting more centered preparations and lower occurrence of lateral perforations and canal transportation. Clinical Relevance: Manual instrumentation is still reported as the main choice in the primary teeth preparation; however, studies have shown limitations in its use. The morphological characteristics of primary teeth and the limited knowledge of shaping procedures in these teeth using mechanical preparation become a challenge for clinical practice and might impair the predictability of endodontic treatment.

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ibrahim Faisal ◽  
Rajab Saif ◽  
Mona Alsulaiman ◽  
Zuhair S. Natto

Abstract Background Various systems of nickel-titanium (NiTi) instrument have long been commercially available. However, the preparation of narrow and curved root canals has always been challenging. The purpose of this study was to compare the shaping ability of two NiTi systems (2Shape and NeoNiTi) in severely curved root canals with different morphological patterns using micro-computed tomography (Micro-CT). Methods A total of 22 human extracted permanent teeth of mandibular first molars, with the exact mesial angle of curvature of 25 and 35 degrees, according to Schneider’s technique, were distributed randomly into two groups (group I: 2Shape, group II: NeoNiTi) based on the rotary system used (n = 22). The groups were subdivided into two subgroups corresponding to the angle of canal curvature (25° and 35°) (n = 11). Canals were scanned using Micro-CT pre- and post-preparation to assess the volume of dentin removed; canal transportation; and canal centering ratio at 3, 6, and 9 mm from the apex. The Mann–Whitney U test was utilized to determine any significant differences between the two systems. The level of statistical significance was set at p < 0.05. Results There was no significant difference between the two groups in volume of dentin removed; canal transportation; and centering ability for 25° and 35° canal curvatures at 3, 6, and 9 mm from the apex (coronal, middle, and apical) thirds (p > 0.05). At the middle third, the NeoNiTi group demonstrated a statistically significant increase in volume of dentin removed for 35° canal curvatures compared to the 2Shape group. Conclusion Within the limitation of our in vitro study, 2Shape and NeoNiTi systems with severely curved canals were confirmed to be relatively safe in preparation and to respect original canal anatomy. Nevertheless, NeoNiTi instruments produced more centered preparation and minimal canal deviation compared to the 2Shape system.


2019 ◽  
Vol 25 ◽  
pp. 6351-6358
Author(s):  
Gabrielė Česaitienė ◽  
Tadas Venskutonis ◽  
Vita Mačiulskienė ◽  
Vaidotas Cicėnas ◽  
Vykintas Samaitis ◽  
...  

Author(s):  
Mahendra Risky Habibi ◽  
Thaqibul Fikri Niyartama

Carbonate rocks have been scanned and reconstructed in order to get the value of specific surface area. We get it from the reservoir at a depth of 1000 metres in South Sumatra. Skyscan Micro-CT 1173 is used for throwing and thresholding images using Global Otshu to characterize rocks. Our calculation result shows that the value of specific surface area of carbonate rocks show results 100 to 10-2 using the programming Algorithm Fuzzy C-Mean. The difference in values far enough that it can be assumed that the carbonate rocks have a heterogeneous surface area. In addition, histogram model shows the similarity of the sample. The macro sample has the same characteristics as the micro sample.


2021 ◽  
Vol 28 (2) ◽  
Author(s):  
Burcu Güçyetmez Topal ◽  
◽  
Seda Falakaloğlu ◽  
Hatice Türkoğlu ◽  
◽  
...  

Objective: The aim of this in vitro study was to evaluate the efficacy of rotary EndoArt Ni-Ti Gold Pedo Kit and K-files in shaping ability, canal transportation, centering ability and instrumentation time in primary molars. Methods: For the study total of 30 extracted primary molars root with minimum 7mm root length were selected. Shaping of root canals in primary molars were done using the two systems, and CBCT and specialized software were used for scanning and analysis of pre-operative and post-operative to evaluate the groups for their shaping properties, apical transportation and preparation time in primary root canals. Results: No differences were found in canal transportation measures and instrumentation time between the two groups (p>0.05). The EndoArt group removed more dentin compared to K-file in all sides of the root curvature. The statistical differences were significant for coronal and middle third of the root (p<0.05). Conclusions: Under the conditions of this study, rotary EndoArt Ni-Ti Gold Pedo Kit provided more conical canals than K-files in primary teeth.


2021 ◽  
Author(s):  
Elliott Goff ◽  
Federica Buccino ◽  
Chiara Bregoli ◽  
Jonathan P. McKinley ◽  
Basil Aeppli ◽  
...  

ABSTRACTUltra-high-resolution imaging of the osteocyte lacuno-canalicular network (LCN) three-dimensionally (3D) in a high-throughput fashion has greatly improved the morphological knowledge about the constituent structures – positioning them as potential biomarkers. Technologies such as serial focused ion beam/scanning electron microscopy (FIB/SEM) and confocal scanning laser microscopy (CLSM) can image in extremely high resolution, yet only capture a small number of lacunae. Synchrotron radiation computed tomography (SR-CT) can image with both high resolution and high throughput but has a limited availability. Desktop micro-computed tomography (micro-CT) provides an attractive balance: high-throughput imaging on the micron level without the restrictions of SR-CT availability. Over the past decade, desktop micro-CT has been used to image osteocyte lacunae in a variety of animals, yet few studies have employed it to image human lacunae using clinical biopsies.In this study, accuracy, precision, and sensitivity of large-scale quantification of human osteocyte lacunar morphometries were assessed by ultra-high-resolution desktop micro-computed tomography. For this purpose, thirty-one transiliac human bone biopsies containing trabecular and cortical regions were imaged using ultra-high-resolution desktop micro-CT at a nominal isotropic voxel resolution of 1.2µm. The resulting 3D images were segmented, component labeled, and the following morphometric parameters of 7.71 million lacunae were measured: Lacunar number (Lc.N), density (Lc.N/BV), porosity (Lc.TV/BV), volume (Lc.V), surface area (Lc.S), surface area to volume ratio (Lc.S/Lc.V), stretch (Lc.St), oblateness (Lc.Ob), sphericity (Lc.Sr), equancy (Lc.Eq), and angle (Lc.θ).Accuracy was quantified by comparing automated lacunar segmentation to manual segmentation. Mean true positive rate (TPR), false positive rate (FPR), and false negative rate (FNR) were 89.0%, 3.4%, and 11.0%, respectively. Regarding the reproducibility of lacunar morphometry from repeated measurements, precision errors were low (0.2 – 3.0%) and intraclass correlation coefficients were high (0.960 – 0.999). Significant differences between cortical and trabecular regions (p<0.001) existed for Lc.N/BV, Lc.TV/BV, local lacunar surface area (<Lc.S>), and local lacunar volume (<Lc.V>), all of which demonstrate the sensitivity of the method and are possible biomarker candidates. This study provides the rigorous foundation required for future large-scale morphometric studies using ultra-high-resolution desktop micro-CT and high-throughput analysis of millions of osteocyte lacunae in human bone samples. Furthermore, the validation of this technology for imaging of human lacunar properties establishes the quality and reliability required for the accurate, precise, and sensitive assessment of osteocyte morphometry in clinical bone biopsies.


2020 ◽  
Vol 14 (01) ◽  
pp. 070-076 ◽  
Author(s):  
Mohamed Mohamed Elashiry ◽  
Shehab Eldin Saber ◽  
Salma Hasan Elashry

Abstract Objectives To evaluate the shaping ability of four different single-file systems using micro-computed tomography (micro-CT). Materials and Methods Eighty mesiobuccal and mesiolingual canals of permanent mandibular molars were randomly assigned to four groups according to the file used; WaveOne Gold, RECIPROC Blue, HyFlex EDM, and One Shape (n = 20). The samples were scanned using micro-CT for the preinstrumentation record; then the canals were instrumented and scanned for the postinstrumentation records. Statistical Analysis The data were then analyzed statistically using one-way analysis of variance (ANOVA) with the level of significance set at α = 0.05. Results The results of canal centering ratio and canal transportation showed that no significant difference was found among the four file groups at the middle and the coronal levels. However, a significant difference was found at the apical level (p < 0.05), where WaveOne Gold showed the best centering ratio and the least amount of canal transportation. The change in the canal volume was significant at the coronal level (p < 0.05), whereas the change in the canal volume was higher for the HyFlex EDM group than the other groups. No significant difference was found between the other groups at the apical level, middle level, or in the total percentage of canal volume. Conclusion WaveOne Gold produced a more centralized canal preparation with a lesser amount of transportation at the apical level. HyFlex EDM showed the highest canal volumetric change at the coronal level. The interim design of the endodontic files has a high impact on the behavior of the file inside the root canal.


2021 ◽  
Vol 11 (3) ◽  
pp. 891
Author(s):  
Taylor Flaherty ◽  
Maryam Tamaddon ◽  
Chaozong Liu

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Javier Alba-Tercedor ◽  
Wayne B. Hunter ◽  
Ignacio Alba-Alejandre

AbstractThe Asian citrus psyllid (ACP), Diaphorina citri, is a harmful pest of citrus trees that transmits Candidatus Liberibacter spp. which causes Huanglongbing (HLB) (citrus greening disease); this is considered to be the most serious bacterial disease of citrus plants. Here we detail an anatomical study of the external and internal anatomy (excluding the reproductive system) using micro-computed tomography (micro-CT). This is the first complete 3D micro-CT reconstruction of the anatomy of a psylloid insect and includes a 3D reconstruction of an adult feeding on a citrus leaf that can be used on mobile devices. Detailed rendered images and videos support first descriptions of coxal and scapus antennal glands and sexual differences in the internal anatomy (hindgut rectum, mesothoracic ganglion and brain). This represents a significant advance in our knowledge of ACP anatomy, and of psyllids in general. Together the images, videos and 3D model constitute a unique anatomical atlas and are useful tools for future research and as teaching aids.


2021 ◽  
Author(s):  
Eva Chatzinikolaou ◽  
Kleoniki Keklikoglou

Micro-computed tomography (micro-CT) is a high-resolution 3D-imaging technique which is now increasingly applied in biological studies focusing on taxonomy and functional morphology. The creation of virtual representations of specimens can increase availability of otherwise underexploited and inaccessible samples. This protocol aims to standardise micro-CT scanning procedures for embryos and juveniles of the marine gastropod species Hexaplex trunculus.


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