scholarly journals Effect of Reciprocating Systems and Working Lengths on Apical Microcrack Development: a micro-CT Study

2017 ◽  
Vol 28 (6) ◽  
pp. 710-714 ◽  
Author(s):  
Bruna Paloma de Oliveira ◽  
Andréa Cruz Câmara ◽  
Daniel Amancio Duarte ◽  
Richard John Heck ◽  
Antonio Celso Dantas Antonino ◽  
...  
Keyword(s):  
Root Canal ◽  
Ct Scanning ◽  
Micro Ct ◽  
Root Canal Preparation ◽  
Cross Sectional ◽  
Isotropic Resolution ◽  
Computed Tomographic ◽  
Working Length ◽  
Group B ◽  
Reciprocating Systems

Abstract The objective of this study was to evaluate the effect of root canal preparation with single-file reciprocating systems at different working lengths on the development of apical microcracks using micro-computed tomographic (micro-CT) imaging. Forty extracted human mandibular incisors were randomly assigned to 4 groups (n=10) according to the systems and working length used to prepare the root canals: Group A - WaveOne Gold at apical foramen (AF), Group B - WaveOne Gold 1 mm short of the AF (AF-1 mm), Group C - Unicone (AF) and Group D - Unicone (AF-1 mm). Micro-CT scanning was performed before and after root canal preparation at an isotropic resolution of 14 µm. Then, three examiners assessed the cross-sectional images generated to detect microcracks in the apical portion of the roots. Apical microcracks were visualized in 3, 1, 1, and 3 specimens in groups A, B, C, and D, respectively. All these microcracks observed after root canal preparation already existed prior to instrumentation, and no new apical microcrack was detected. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal preparation with WaveOne Gold and Unicone, regardless of the working length, was not associated with apical microcrack formation.

Observation of the Pulp Chamber of Maxillary First Premolars: A Micro-computed Tomographic Study

2020 ◽  
Vol 16 (3) ◽  
pp. 224-230
Author(s):  
Gozde Serindere ◽  
Ceren Aktuna Belgin ◽  
Kaan Orhan
Keyword(s):  
Root Canal ◽  
Age Groups ◽  
Slice Thickness ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Pulp Chamber ◽  
Anatomical Structures ◽  
Computed Tomographic ◽  
The Mean ◽  
Chamber Floor

Background: There are a few studies about the evaluation of maxillary first premolars internal structure with micro-computed tomography (micro-CT). The aim of this study was to assess morphological features of the pulp chamber in maxillary first premolar teeth using micro- CT. Methods: Extracted 15 maxillary first premolar teeth were selected from the patients who were in different age groups. The distance between the pulp orifices, the diameter of the pulp and the width of the pulp chamber floor were measured on the micro-CT images with the slice thickness of 13.6 µm. The number of root canal orifices and the presence of isthmus were evaluated. Results: The mean diameter of orifices was 0.73 mm on the buccal side while it was 0.61 mm on palatinal side. The mean distance between pulp orifices was 2.84 mm. The mean angle between pulp orifices was -21.53°. The mean height of pulp orifices on the buccal side was 4.32 mm while the mean height of pulp orifices on the palatinal side was 3.56 mm. The most observed shape of root canal orifices was flattened ribbon. No isthmus was found in specimens. Conclusion: Minor anatomical structures can be evaluated in more detail with micro-CT. The observation of the pulp cavity was analyzed using micro-CT.

scholarly journals A Microcomputed Tomographic Evaluation of Root Canal Morphology of Maxillary Second Premolars in a Pakistani Cohort

2021 ◽  
Vol 11 (11) ◽  
pp. 5086
Author(s):  
Mazen F. Alkahtany ◽  
Saqib Ali ◽  
Abdul Khabeer ◽  
Shafqat A. Shah ◽  
Khalid H. Almadi ◽  
...  
Keyword(s):  
Root Canal ◽  
Three Dimensional ◽  
Ct Scanning ◽  
Micro Ct ◽  
Single Root ◽  
Root Canal Morphology ◽  
Spss Software ◽  
Variable Morphology ◽  
Canal Morphology

This study aimed to investigate variations in the root canal morphology of maxillary second premolar (MSP) teeth using microcomputed tomography (micro-CT). Sixty (N = 60) human extracted MSPs were collected and prepared for micro-CT scanning. The duration for scanning a single sample ranged between 30 and 40 min and a three-dimensional (3-D) image was obtained for all the MSPs. The images were evaluated by a single observer who recorded the canal morphology type, number of roots, canal orifices, apical foramina(s), apical delta(s), and accessory canals. The root canal configuration was categorized in agreement with Vertucci’s classification, and any configuration not in agreement with Vertucci’s classification was reported as an “additional canal configuration”. Descriptive statistics (such as mean percentages) were calculated using SPSS software. The most common types agreeing with Vertucci’s classification (in order of highest to lowest incidence) were types I, III, V, VII, II, and VI. The teeth also exhibited four additional configurations that were different from Vertucci’s classification: types 2-3, 1-2-3, 2-1-2-1, and 1-2-1-3. A single root was found in 96.7% and the majority of the samples demonstrated two canals (73.3%). Further, 80% of the teeth showed one canal orifice. The number of apical foramina’s in the teeth was variable, with 56.7% having solitary apical foramen. The accessory canal was found in 33.3%, and apical delta was found in only 20% of the samples. Variable morphology of the MSPs was detected in our study. The canal configuration most prevalent was type 1; however, the results also revealed some additional canal types.

scholarly journals Shaping ability of rotary or reciprocating systems for oval root canal preparation: a micro-computed tomography study

2018 ◽  
Vol 22 (9) ◽  
pp. 3189-3194 ◽  
Author(s):  
Camila Galletti Espir ◽  
Camila Almeida Nascimento-Mendes ◽  
Juliane Maria Guerreiro-Tanomaru ◽  
Bruno Cavalini Cavenago ◽  
Marco Antonio Hungaro Duarte ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Root Canal ◽  
Micro Computed Tomography ◽  
Root Canal Preparation ◽  
Reciprocating Systems ◽  
Shaping Ability

scholarly journals Micro-CT Evaluation of Non-instrumented Canal Areas with Different Enlargements Performed by NiTi Systems

2015 ◽  
Vol 26 (6) ◽  
pp. 624-629 ◽  
Author(s):  
Gustavo De-Deus ◽  
Felipe Gonçalves Belladonna ◽  
Emmanuel João Nogueira Leal Silva ◽  
Juliana Roter Marins ◽  
Erick Miranda Souza ◽  
...  
Keyword(s):  
Surface Area ◽  
Root Canal ◽  
Repeated Measures ◽  
Significance Level ◽  
Isotropic Resolution ◽  
Computed Tomographic ◽  
Mandibular Molars ◽  
Canal Surfaces ◽  
Before And After ◽  
Ct Evaluation

The aim of this study was to compare the percentage of non-instrumented area of root canals prepared with different enlargements using single-file reciprocating systems (Reciproc and WaveOne) and a conventional multi-file rotary (BioRaCe) system by micro-computed tomographic analysis. Thirty mesial roots of mandibular molars with moderate curvature (10° to 20°) presenting a type II Vertucci canal configuration and similar internal volume were chosen and scanned at an isotropic resolution of 14.16 µm. The sample was assigned to 3 groups (n=10) according to the system used for root canal preparation: Reciproc, WaveOne, and BioRaCe groups. Second and third scans were taken after the canals were prepared with instruments sizes 25 and 40, respectively. The recorded images of the surface area voxels of the canals, before and after preparation were examined from the furcation level to the apex to quantify the non-instrumented surface. Statistical data were compared using GLM for repeated-measures with a significance level set at 5%. Instrumentation systems did not influence the percentage of untouched root canal surfaces (p=0.690) whilst a significant reduction in the percentage of static voxels was observed after the enlargement of the root canal (p=0.010) in all groups (p=0.507). None of the systems was able to prepare the entire surface area of the mesial root canal of mandibular molars. The increased final apical size resulted in a significant positive effect on the shaping ability of the tested systems.

Preliminary Simulation of the Flow in the Root Canal Using New Irrigation Needle

2015 ◽  
Vol 772 ◽  
pp. 621-625 ◽  
Author(s):  
Dragoș Isvoranu ◽  
Sterian Danaila
Keyword(s):  
Shear Stress ◽  
Root Canal ◽  
Volume Fraction ◽  
Great Efficiency ◽  
Root Canal Preparation ◽  
Two Phase ◽  
Irrigation Flow ◽  
Working Length ◽  
Two Component ◽  
Simulation Results

The main purpose of this paper is to explore the possibility of using a new irrigation device to achieve the goals of root canal preparation for endodontic procedures. A secondary goal is to introduce the never before used physical approach of two-phase, two-component irrigation flow in the root canal. Our simulation results show great efficiency of the irrigation procedure in terms of the irrigant volume fraction and wall shear stress at the wall of the root canal over entire working length.

scholarly journals The Guiding Effect of Digital Image Based on Cone-Beam Computed Tomographic on Oval Root Canal Preparation

2021 ◽  
Author(s):  
Yiwei Wang ◽  
Wenjun Xia ◽  
Zisheng Tang ◽  
Yan Zou ◽  
Xiaohe Bian ◽  
...  
Keyword(s):  
Digital Image ◽  
Root Canal ◽  
Cone Beam ◽  
Control Group ◽  
Root Canal Preparation ◽  
Computed Tomographic ◽  
Significant Difference ◽  
3D Printed ◽  
Experimental Group ◽  
Guiding Effect

Abstract Background: To evaluate the guiding effect of digital image based on cone-beam computed tomographic in improving the quality of single oval root canal preparation.Methods: A premolar was selected by CBCT and a 3D-printed root canal model was made. Twenty postgraduates from the Department of Stomatology of Shanghai Ninth People's Hospital were selected to perform root canal preparation on 3D printed oval root canal model teeth. They were randomly assigned to two groups(n=10) according to the guiding method received: CBCT original image (control group) and CBCT-based digital image (experimental group). CBCT scans were performed on the models before and after the guidance. The changes in root canal cleanliness, residual minimum thickness, transportation and over-preparation amount were analyzed.Results: The experimental group caused significantly more increased amount of cleanliness compared to control group(P<0.05)：6.0373% ±6.0766% in the control group and 13.7193%±6.7102% in the experimental group. There was no significant difference in the reduction of residual minimum wall thickness between the two groups (P>0.05)： 0.0154mm±0.2110mm in the control group and 0.0362±0.0444mm in the experimental group. In the control group, the transportation after second preparation was generally increased (increased 0.0084mm on average). In the experimental group, the transportation was generally reduced after second preparation (reduced 0.0081mm on average). But there was no significant difference in the transportation change between the two groups (P>0.05). After the second preparation, there was no significant difference in the amount of increased over-preparation between the two groups（P＞0.05）: 1.7029%±3.6622% in the control group and 3.5144%±4.8075% in the experimental group.Conclusions: Compared with traditional CBCT image guidance, the digital image method can significantly improve the cleaning effect of the oval root canal preparation. It didn’t result in more over-preparation and the amount of residual wall thickness was ensured. At the same time, it has a certain effect on reducing transportation after the guidance.

scholarly journals Influence of voxel size on dentinal microcrack detection by micro-CT after root canal preparation

2021 ◽  
Vol 35 ◽  
Author(s):  
Jáder Camilo PINTO ◽  
Hernán COAGUILA-LLERENA ◽  
Fernanda Ferrari Esteves TORRES ◽  
Éverton LUCAS-OLIVEIRA ◽  
Tito José BONAGAMBA ◽  
...  
Keyword(s):  
Root Canal ◽  
Micro Ct ◽  
Root Canal Preparation ◽  
Voxel Size ◽  
Microcrack Detection

Objective antitumor activity of acivicin in patients with recurrent CNS malignancies: a Southwest Oncology Group trial.

1991 ◽  
Vol 9 (8) ◽  
pp. 1476-1479 ◽  
Author(s):  
S A Taylor ◽  
J Crowley ◽  
T W Pollock ◽  
H J Eyre ◽  
C Jaeckle ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Performance Status ◽  
Ct Scanning ◽  
Oncology Group ◽  
Cross Sectional ◽  
Southwest Oncology Group ◽  
Computed Tomographic ◽  
Malignant Astrocytomas ◽  
Mri Scans ◽  
Cns Malignancies

Acivicin (AT-125) is a glutamine antagonist with dose-limiting, schedule-dependent CNS toxicity and predictable CSF penetration after intravenous administration. Because of these properties, a trial in CNS malignancies was initiated. Thirty-two patients with recurrent or residual malignant astrocytomas were treated with AT-125. The majority of patients had glioblastoma multiforme (24) and had received prior nitrosoureas (21). The median age was 50 years, and Southwest Oncology Group (SWOG) performance status was 2. The major determinant of response was based upon radiologic criteria using computed tomographic (CT) scanning and/or magnetic resonance imaging (MRI) scans. The tumor mass was measured in two perpendicular planes, which yielded the largest cross-sectional area. Standard solid tumor criteria for response were used. All responding patients also had a stable or tapered dose of corticosteroids with stable or improved performance status and neurologic examination. There were four objective responses (12%): one complete remission (3 1/2+ years) and three partial remissions (57, 86, and 322 days). Two patients had improvement in disease that did not meet requirements for a partial remission. Toxicity was mild and primarily consisted of nausea, vomiting, and lethargy. Two patients were removed from study due to neurotoxicity (depression and hallucinations). The strict response criteria used in this trial were not those that have been used in testing other active agents such as carmustine (BCNU). We conclude that AT-125 has objective antitumor activity in malignant astrocytomas and warrants further study.

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