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1.
Navid Akbarzadeh Anita Aminoshariae Navid Khalighinejad J. Martin Palomo Ali Syed James C. Kulild Ghazal Sadeghi Andre Mickel 《Journal of endodontics》2017,43(11):1797-1801
Introduction
The present study aimed to determine the incidence and anatomic variation of the middle mesial (MM) canal in mandibular permanent first molars using cone-beam computed tomographic imaging and to evaluate the association between the presence of MM canals and anatomic landmarks of the pulp chamber floor in the mesial root.Methods
In this in vivo cross-sectional study, 210 CBCT scans of mandibular fist molars from 210 patients were included. CBCT scans were evaluated in 3 sections, and the following data were collected for further analysis: identification of the MM canal, the distance between the mesiobuccal (MB) and mesiolingual (ML) orifices, the presence of any isthmus between the MB and ML orifices, and the MB and ML root canal system (RCS) configurations. Binary logistic regression was performed to assess the effect of pulp floor anatomic characteristics as an independent variable on the outcome variable (the presence of an MM canal).Results
The overall prevalence of the identification of an MM canal regardless of age was 14.7%. Mandibular first molars with an isthmus between the MB and ML RCS configurations were almost 5 times more likely to show an MM canal (P < .05, odds ratio [OR] = 4.9). The MB-ML intraorifice distance was inversely associated with the presence of an MM canal (P < .05, OR = 0.73). Patients less than 42 years old were 4 times more likely to have an MM canal in their CBCT scans compared with patients older than 42 years old (P < .05, OR = 3.9).Conclusions
The suggested anatomic landmarks of the pulp chamber floor could act as a reliable predictive factor for the presence of an MM canal. This knowledge of anatomic clues may serve to better direct endodontists in locating an MM canal, which could prevent excessive removal of tooth structures. 相似文献2.
Roserin Ratanajirasut Anchana Panichuttra Soontra Panmekiate 《Journal of endodontics》2018,44(1):56-61
Introduction
Understanding tooth anatomy is crucial for effective endodontic treatment. This study investigated the roots and root canal morphology of maxillary first and second permanent molars in a Thai population using cone-beam computed tomographic (CBCT) imaging.Methods
This study evaluated 476 maxillary first molars and 457 maxillary second molars receiving CBCT examination and determined the number of roots and canal morphology according to Vertucci's classification, and the prevalence of a second mesiobuccal (MB2) canal in the mesiobuccal (MB) root was correlated with sex, age, and tooth side.Results
Three roots were most commonly found in maxillary first and second molars. MB2 canals in the MB root were found in 63.6% and 29.4% of first and second molars, respectively. The most common canal morphology in the first molar MB roots was type I (36.4%) followed by type II (28.8%), and type IV (25.3%). The most common canal morphology in the second molar MB roots was type I (70.6%) followed by type II (14.6%) and type IV (7.5%). Bilateral MB2 canals in the MB roots were present in 80.93% and 82.59% of the first and second molars, respectively. There was a significant correlation between males and the prevalence of MB2 canals in first molars (P < .05).Conclusions
CBCT imaging is useful to determine root canal morphology. The prevalence of MB2 canals is approximately 60% and 30% in first and second molars, respectively. Furthermore, bilateral MB2 canals were commonly found. Our results can help endodontists to improve endodontic treatment outcomes. 相似文献3.
Ben Studebaker Lars Hollender Lloyd Mancl James D. Johnson Avina Paranjpe 《Journal of endodontics》2018,44(4):565-570
Introduction
Many endodontic treatment failures in maxillary molars result from missed second mesiobuccal (MB2) canals. An MB2 canal orifice is present in as many as 95% of maxillary molars, but these canals are not always located during endodontic procedures. Additional tools, such as cone-beam computed tomographic (CBCT) imaging, may be needed to locate these canals in maxillary molars. Hence, the aims of this study were to investigate the frequency of use of CBCT imaging during the treatment of maxillary molars and to evaluate the influence of its use on the detection of MB2 canals.Methods
Endodontic treatment records, digital intraoral radiographs (when present), and CBCT images from all maxillary first and second?molars treated at the University of Washington, Seattle, WA, between 2010 and 2014 (N?=?886) were reviewed. Statistical analysis was performed to assess differences between the groups.Results
Overall, an MB2 canal was found in 55.8% of the maxillary molars studied, and CBCT imaging assisted in detecting 11.7% of these canals. CBCT imaging was used in 16.5% of the cases treated and was used significantly more for retreatment cases. CBCT imaging was used preoperatively in 5.6% of cases, and the data show that significantly more MB2 canals were located when a preoperative CBCT image was available. More MB2 canals were located in first molars without full-coverage crowns.Conclusions
The data show that CBCT imaging is a valuable tool in locating MB2 canals. Based on the results of his study, the use of CBCT imaging could be warranted when treating maxillary molars. 相似文献4.
Introduction
This study evaluated the cyclic fatigue resistance (CFR) of Reciproc (R25 and R40; VDW, Munich, Germany) and Reciproc Blue (R25 and R40, VDW) instruments used in an artificial S-shaped canal.Methods
A total of 80 files were tested in an S-shaped canal (n = 20 for each file, Reciproc R25 and R40 and Reciproc Blue R25 and R40). This study compared Reciproc R25 with Reciproc Blue R25 files and Reciproc R40 with Reciproc Blue R40 files. All files were rotated in an S-shaped artificial canal until fracture. CFR was determined by recording the time to fracture in the artificial canal. The length of each fractured fragment was measured in millimeters. An independent sample t test was used to analyze the data.Results
Between the R25 files, Reciproc Blue instruments showed significantly greater CFR than the Reciproc files in the apical and coronal curves (P < .05). Between the R40 files, Reciproc Blue instruments exhibited greater CFR in the apical and coronal curves (P < .05). There was no difference in the fractured fragment lengths of the Reciproc Blue files compared with the Reciproc files (P > .05).Conclusions
The Reciproc Blue R25 and R40 files showed greater CFR than the Reciproc R25 and R40 files in an S-shaped canal. 相似文献5.
Sabrina C. Brasil Marília F. Marceliano-Alves Márcia L. Marques João P. Grillo Mariane F.L.S. Lacerda Flávio R.F. Alves José F. Siqueira José C. Provenzano 《Journal of endodontics》2017,43(10):1683-1687
Introduction
This study compared the shaping ability of ProTaper Next (Dentsply Sirona, Tulsa, OK) and BT-RaCe (FKG Dentaire, La Chaux-de-Fonds, Switzerland) instrument systems in the mesial canals of mandibular molars using micro–computed tomographic (micro-CT) imaging.Methods
A total of 17 type IV mesial roots of extracted first mandibular molars were scanned using micro-CT imaging before and after root canal preparation with the 2 instrument systems. Both systems were used in the same root but alternating the mesial canals from root to root. The following parameters were analyzed: root canal volume, surface area, unprepared surface areas, transportation, canal/root width ratio, and preparation time.Results
There were no statistically significant differences between the 2 systems for all evaluated parameters (P > .05). The unprepared surface areas for the full canal length and the apical 5-mm segment were 33% and 14% for BT-RaCe and 31% and 14% for ProTaper Next, respectively. After preparation, all root canals had a diameter that was not larger than 35% of the root diameter at the coronal and middle segments.Conclusions
The 2 systems showed no differences in any of the evaluated shaping parameters. None of the tested systems put the roots at risk of fracture because of excessive dentin removal. 相似文献6.
Jorge N.R. Martins Moataz-Bellah A.M. Alkhawas Zaher Altaki Gianmarco Bellardini Luiza Berti Carlos Boveda Antonis Chaniotis Daniel Flynn Jose Antonio Gonzalez Jojo Kottoor Miguel Seruca Marques Adam Monroe Hani F. Ounsi Peter Parashos Gianluca Plotino Magnús F. Ragnarsson Ruben Rosas Aguilar Fábio Santiago António Ginjeira 《Journal of endodontics》2018,44(11):1641-1649.e1
Introduction
Maxillary first molar second mesiobuccal (MB2) root canal prevalence may change among different populations. The aim of this study was to analyze the worldwide prevalence of the MB2 root canal and understand its possible relation with sex, age, side, and root configuration using in vivo cone-beam computed tomographic (CBCT) assessment.Methods
Observers from 21 regions were calibrated to achieve a similar CBCT assessment methodology and instructed to collect data from 250 maxillary first molars in previously existing examinations. Intra- and interrater reliability tests were performed. The sample size included 5250 molars and was defined by way of a preliminary trial. Data collected included MB2 presence, sex, age, side, number of roots per tooth, and mesiobuccal root configuration. The z test for proportions in independent groups was used to analyze the differences among subgroups. P < .05 was considered significant.Results
The worldwide CBCT-assessed MB2 prevalence was 73.8%, ranging from 48.0% in Venezuela to 97.6% in Belgium. The prevalence in males and females was 76.3% and 71.8%, respectively (P < .05). Significantly higher MB2 proportions were found in younger patients and 3-rooted molar configurations. The group intraclass correlation coefficient and the percentage of agreement for the MB2 presence were 0.95 and 0.91, respectively. The intrarater Cohen kappa value was above 0.61 for all observers.Conclusions
MB2 prevalence in the analyzed regions varied widely. The differences may be associated with specificities within each region but also patient demographics. Males, younger patients, and 3-rooted configurations were associated with higher MB2 proportions. 相似文献7.
H. Melike Bayram Emre Bayram Mert Ocak M. Bora Uzuner Ferhat Geneci Hakan Hamdi Celik 《Journal of endodontics》2017,43(10):1736-1739
Introduction
The aim of the present study was to evaluate the frequency of dentinal microcracks observed after root canal preparation with HyFlex CM (Coltène/Whaledent, Altstätten, Switzerland), HyFlex EDM (Coltène/Whaledent), Vortex Blue (Dentsply Tulsa Dental Specialties, Tulsa, OK), and TRUShape (Dentsply Tulsa Dental Specialties) systems using micro–computed tomographic (micro-CT) analysis.Methods
Forty human mandibular incisors with 1 and straight root canals were randomly assigned to 4 experimental groups (n = 10) and 1 control group for root canal preparation: group 1, HyFlex CM; group 2, HyFlex EDM; group 3, Vortex Blue; and group 4, TRUShape. The specimens were scanned using high-resolution micro-CT imaging before and after root canal preparation. Afterward, preoperative and postoperative cross-sectional images of the teeth were screened to identify the presence of dentinal defects. The number of microcracks was determined as a percentage for each group.Results
Before and after canal preparation, 36,152 cross-sectional images were examined. Four thousand four hundred fifty-two (12.31%) dentinal defects were observed. No new microcracks were observed after root canal instrumentation with the tested systems.Conclusions
Root canal preparation with the HyFlex CM, HyFlex EDM, Vortex Blue, and TRUShape systems did not induce the formation of new dentinal microcracks on straight root canals of mandibular incisors. 相似文献8.
Juan Wen Shu Liu Xiao Ye Xiaoqiu Xie Jialing Li Huang Li Li Mei 《Journal of the American Dental Association (1939)》2017,148(12):913-921
Background
The authors conducted a study to compare 2-dimensional (2D) lateral cephalometric radiography (LCR), 2D cone-beam computer tomographic (CBCT)–generated cephalogram and 3-dimensional (3D) CBCT for assessing cephalometric measurements.Methods
The authors took 2D LCR, 2D CBCT-generated cephalogram, and 3D CBCT images involving 60 participants. They obtained 11 angular and 11 linear measurements for all images. They used 1-way analysis of variance and the Fisher least significant difference test for statistical comparisons. The authors used Pearson correlation and Pearson χ2 test to assess the relationship of these imaging modalities for vertical cephalometric analyses.Results
Significant differences existed between the 2D cephalograms (LCR and CBCT-generated cephalogram) and the 3D CBCT in 2 angular measurements (maxillary first incisor-nasion (N) point A [A] and mandibular first incisor-N point B (B) (P = .027 and P < .001, respectively) and 5 linear measurements (N menton[Me]/sella gonion [Go], condylion [Co]A, Co gnathion, Go-Me and anterior nasal spine-posterior nasal spine) (P < .004). These measurement values with significant differences were generally greater (approximately 5° for angular measurements and 10 millimeters for linear measurements) on the 3D CBCT scans than on the 2D cephalograms. No significant difference was found between the 2 2D cephalograms (P > .164). No significant difference was found among the 3 imaging modalities for the vertical cephalometric analyses (P > .466).Conclusions
Significant differences existed between the 2D cephalograms (LCR and CBCT-generated cephalogram) and the 3D CBCT scans in 2 angular and 5 linear measurements. The 2 2D cephalograms were similar for cephalometric measurements. The 3 imaging modalities had no significant difference for the vertical cephalometric analyses. CBCT might not add value for every orthodontic situation.Practical Implications
These results find the values of cephalometric measurements on 3D CBCT scans may be greater than on the conventional LCR for some parameters. The 2D CBCT-generated cephalogram could be an alternative to the conventional LCR for patients whose large-field-of-view CBCT images are already available. 相似文献9.
Cosimo Nardi Linda Calistri Silvia Pradella Isacco Desideri Chiara Lorini Stefano Colagrande 《Journal of endodontics》2017,43(10):1640-1646
Introduction
This study aimed to evaluate the diagnostic accuracy of orthopantomography (OPT) for the detection of clinically/surgically confirmed apical periodontitis (AP) without endodontic treatment using cone-beam computed tomographic (CBCT) imaging as the reference standard.Methods
One hundred twenty patients without endodontically treated AP (diseased group) were detected via CBCT imaging using the periapical index system. They were divided into groups of 10 each according to the size of the lesion (2–4.5 mm and 4.6–7 mm) and the anatomic area (incisor, canine/premolar, and molar) in both the upper and lower arches. Another 120 patients with a healthy root and periapex (healthy group) were selected. Each diseased and healthy patient underwent OPT first and a CBCT scan within 40 days of the OPT. The periapical index system was also used to assess AP by OPT. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for OPT images with respect to CBCT imaging were analyzed. The k value was calculated to assess both the interobserver reliability for OPT and the agreement between OPT and CBCT imaging.Results
OPT showed low sensitivity (34.2), negative predictive value (59.3), and diagnostic accuracy (65.0) and high specificity (95.8) and positive predictive value (89.1). Interobserver reliability for OPT was substantial (k = 0.71), and agreement between OPT and CBCT imaging was fair (k = 0.30). The best and worst identified AP were located in the lower molar area and the upper/lower incisor area, respectively.Conclusions
OPT showed high specificity and positive predictive value. However, overall, it was not an accurate imaging technique for the detection of untreated AP, especially in the incisor area. 相似文献10.
Po-Yen Lin Yu-Chih Chiang Yu-Ju Chou Hong-Ji Chang Lin-Yang Chi 《Journal of endodontics》2017,43(1):29-35
Introduction
The objective of root canal treatments (RCTs) is to control pulpal diseases and salvage infected teeth by eradicating microorganisms within the root canal system. However, an unfinished RCT can leave a space for bacterial accumulation, which can leak into the oral cavity and then aspirate into the lower respiratory tract and the lungs, causing infection. This study investigated the association of unfinished RCTs with the possible risk of pneumonia hospitalization using a nationwide population-based database.Methods
After a matching process, we recruited 116,490 subjects who received an initiated RCT and had no history of pneumonia before 2005 and observed until the end of 2011. An unfinished RCT was operationally defined as an endodontic session that was started on a tooth but had no subsequent completion records. Cox proportional hazards models and subgroup analyses were used to estimate the association of unfinished RCTs on the risk of pneumonia hospitalization.Results
In total, 1285 subjects were hospitalized for pneumonia during 2005 to 2011 with an overall pneumonia hospitalization incidence rate of 0.22% per person year. After adjusting for confounding factors, the adjusted pneumonia hospitalization hazard ratio for subjects who had unfinished RCTs was 1.40 (95% confidence interval, 1.24–1.59) compared with subjects without unfinished RCTs (P < .0001). For middle-aged patients, the hazard ratio was 1.81 (95% confidence interval, 1.45–2.24).Conclusions
Patients with unfinished RCTs had a higher risk of pneumonia hospitalization. Thus, dentists are advised to complete endodontic treatments once started. 相似文献11.
Victor Aquino Wanderley Frederico Sampaio Neves Monikelly Carmo Chagas Nascimento Gabriela Queiroz de Melo Monteiro Natália Siqueira Lobo Matheus Lima Oliveira Joao Batista Sobrinho Nascimento Neto Luciane Farias Araujo 《Journal of endodontics》2017,43(10):1720-1724
Introduction
The purpose of this study was to compare different high-resolution cone-beam computed tomographic (CBCT) imaging protocols in the diagnosis of incomplete root fractures of endodontically treated teeth.Methods
Twenty single-rooted human teeth were endodontically treated, and an incomplete root fracture was induced. The teeth were scanned with the CBCT unit PreXion 3D (Teracom, San Mateo, CA) operating at 2 different protocols: high resolution/standard (HI-STD) (19 seconds and 512 basis images) and high resolution/high density (HI-HI) (37 seconds and 1024 basis images). Three oral radiologists evaluated all images using multiplanar reconstructions. The diagnostic tests and the receiver operating characteristic (ROC) curve were calculated.Results
The HI-STD and HI-HI protocols presented an accuracy of 0.90 and 0.93, respectively, and both protocols had a sensitivity of 0.97. The HI-HI protocol showed a higher positive predictive value and slightly higher areas under the ROC curve.Conclusions
Both high-resolution imaging protocols presented high accuracy in the detection of incomplete root fracture of endodontically teeth. Thus, the HI-STD protocol should be indicated this reduces the radiation dose. 相似文献12.
Statement of problem
Selecting material for a minimally invasive occlusal veneer reconstruction concept requires an understanding of how stresses are distributed during functional and parafunctional forces.Purpose
The purpose of this in vitro study was to investigate stress distribution in a maxillary molar restored with ultrathin occlusal veneers and subjected by an antagonistic mandibular molar to clenching and working and nonworking movements.Material and Methods
A maxillary first molar was modeled from microcomputed tomography (micro-CT) data, using medical image processing software, stereolithography editing/optimizing software, and finite element software. Simulated ultrathin occlusal veneer materials were used. The mandibular molar antagonist was a solid nondeformable geometric entity. Loads simulated clenching, working, and nonworking movements with loading of 500 N. The values of the maximum principal stress were recorded.Results
In the clenching load situation, maximum tensile stresses were located at the occlusal veneer (52 MPa for composite resin versus 47 MPa for ceramic). In the working movement, significant additional tensile stresses were found on the palatal root (87 MPa for composite resin and 85 MPa for ceramic). In the nonworking movement, tensile stress on the ultrathin occlusal veneer increased to 118 MPa for composite resin and 143 MPa for ceramic veneers. Tensile stress peaks shifted to the mesiobuccal root (75 MPa for composite resin and 74 MPa for ceramic).Conclusions
The topography of stresses generated by the various occlusal interferences were clearly identified. Significant tensile stress concentrations were found within the restoration’s occlusal topography and root, with the nonworking interference being the most harmful and also the most revealing of the difference between the composite resin and ceramic ultrathin occlusal veneers. 相似文献13.
Abdulaziz AlHelal Hamad S. AlRumaih Mathew T. Kattadiyil Nadim Z. Baba Charles J. Goodacre 《The Journal of prosthetic dentistry》2017,117(2):233-238
Statement of problem
Clinical studies comparing the retention values of milled denture bases with those of conventionally processed denture bases are lacking.Purpose
The purpose of this clinical study was to compare the retention values of conventional heat-polymerized denture bases with those of digitally milled maxillary denture bases.Material and methods
Twenty individuals with completely edentulous maxillary arches participated in this study. Definitive polyvinyl siloxane impressions were scanned (iSeries; Dental Wings), and the standard tessellation language files were sent to Global Dental Science for the fabrication of a computer-aided design and computer-aided manufacturing (CAD-CAM) milled denture base (group MB) (AvaDent). The impression was then poured to obtain a definitive cast that was used to fabricate a heat-polymerized acrylic resin denture base resin (group HB). A custom-designed testing device was used to measure denture retention (N). Each denture base was subjected to a vertical pulling force by using an advanced digital force gauge 3 times at 10-minute intervals. The average retention of the 2 fabrication methods was compared using repeated ANOVA (α=.05).Results
Significantly increased retention was observed for the milled denture bases compared with that of the conventional heat-polymerized denture bases (P<.001).Conclusions
The retention offered by milled complete denture bases from prepolymerized poly(methyl methacrylate) resin was significantly higher than that offered by conventional heat- polymerized denture bases. 相似文献14.
Introduction
Mandibular premolars that have rare and complex anatomies may have the highest failure rate in nonsurgical endodontic treatment. Awareness of rare and complex anatomies of mandibular second premolars would aid in better outcomes of the treatment. This study aimed to evaluate the success of nonsurgical root canal treatment of mandibular second premolar teeth with complex apical branching.Methods
Twenty-six mandibular second premolar teeth with complex apical branching treated with multiple-visit nonsurgical root canal treatment or nonsurgical retreatment were retrospectively evaluated.Results
For the clinical outcomes, 9 subjects had complete healing, 1 subject had functional healing, and no subject had no healing scores out of 10 root canal treatment subjects. Six subjects had complete healing, 8 subjects had functional healing, and 2 subjects had no healing scores out of 16 retreatment subjects. For the radiographic outcomes, 7 subjects had complete healing, 3 subjects had incomplete healing, and no subject had no healing scores out of 10 root canal treatment subjects. Six subjects had complete healing, 8 subjects had incomplete healing, and 2 subjects had no healing scores out of 16 retreatment subjects. The clinical outcome of root canal treatment subjects was significantly different than retreatment subjects (P < .05). Similarly, the radiographic outcome of root canal treatment subjects was also significantly different than retreatment cases (P < .05).Conclusions
The outcome of endodontic treatment of mandibular second premolars may be influenced by treatment type. 相似文献15.
Introduction
The aim of this study was to evaluate the accuracy of working length determination by using an electronic apex locator, periapical radiography, and cone-beam computed tomographic (CBCT) imaging obtained at different voxel sizes and field of views (FOVs) in extracted human teeth.Methods
Thirty extracted human mandibular premolar teeth were used. The electronic working length measurements were performed by using an electronic apex locator (Root ZX; J Morita Corp, Kyoto, Japan). Five different image sets were obtained as follows:(1) CBCT imaging: 40 × 40 mm FOV, 0.080 mm3 (FOV40);(2) CBCT imaging: 60 × 60 mm FOV, 0.125 mm3 (FOV60);(3) CBCT imaging: 80 × 80 mm FOV, 0.160 mm3 (FOV80);(4) CBCT imaging: 100 × 100 mm FOV, 0.250 mm3 (FOV100); and(5) periapical digital radiography. Direct measurements performed with an electronic digital caliper were considered as the gold standard and compared with the electronic apex locator, CBCT, and periapical image measurements. Data were analyzed using a 2-way analysis of variance test. Significance level was set at P < .05.Results
There was no significant difference between or within operators in intraoral radiographs (P > .05 and the Gage R&R value was <30%). There were significant differences between and within operators for CBCT images (P < .05 and Gage R&R value was >30%). There were significant differences in the methods in terms of mean differences from the gold standard (P < .05).Conclusions
This study showed that available CBCT scans with different FOVs can be used for working length measurement. 相似文献16.
Ersan Çiçek Neslihan Yılmaz M. Murat Koçak Baran Can Sağlam Sibel Koçak Burcu Bilgin 《Journal of endodontics》2017,43(10):1697-1700
Introduction
The aim of this study was to compare the fracture resistance of simulated immature teeth after using different thicknesses of mineral trioxide aggregate (MTA) apical plugs.Methods
Fifty-two human maxillary anterior teeth were used. Five teeth were the positive control group; they were prepared using Peeso reamers to simulate immature teeth without any access cavity preparation. Access cavities of the 47 teeth were prepared, and the canals were instrumented with Peeso reamers. Five teeth served as the negative control; they were filled with calcium hydroxide. Forty-two teeth were divided into 3 groups; in groups 1, 2, and 3, MTA was placed into canals as a 3-mm and a 6-mm apical plug and a thorough canal length, respectively. The rest of the canals in groups 1 and 2 were filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany). After the storage period, the roots were covered with a polyether impression material and were embedded into self-curing resin blocks. Each specimen was then subjected to fracture testing using a universal testing machine. Data were analyzed using 1-way analysis of variance with the Tukey post hoc test for multiple comparisons.Results
The negative group showed the lowest fracture resistance compared with the other groups. The 3-mm apical plug group showed the highest fracture resistance (P < .05). No significant differences were found between the 3-mm and 6-mm apical plug groups (P > .05).Conclusions
MTA should be used as an apical plug instead of root canal filling material to increase the fracture resistance of immature teeth. 相似文献17.
Hugo Gaêta-Araujo Gabriela Queiroz Silva de Souza Deborah Queiroz Freitas Christiano de Oliveira-Santos 《Journal of endodontics》2017,43(10):1668-1673
Introduction
There is no consensus about the accuracy of cone-beam computed tomography (CBCT) for detecting vertical root fractures (VRFs), nor is there certainty about the isolated effect of different tube current parameters on the diagnosis of VRF through CBCT scans. This study aimed to evaluate how tube current affects the detection of VRF on CBCT examinations in the absence of intracanal materials and in the presence of gutta-percha (GP) and metal (MP) or fiberglass (FP) intracanal posts.Methods
The sample consisted of 320 CBCT scans of tooth roots with and without VRF divided into 8 groups: no fracture/no intracanal material; no fracture + GP; no fracture + MP; no fracture + FP; fracture/no intracanal material; fracture + GP; fracture + MP; fracture + FP. The scans were acquired with an OP300 unit using 4 different milliamperes (4 mA, 8 mA, 10 mA, 13 mA). Five oral radiologists analyzed the images. The area under the receiver operating characteristic curve (Az), sensitivity, specificity, positive and negative predictive values, and interobserver agreement were calculated.Results
Diagnostic performance for the different milliamperes tested was similar for teeth without root filling materials or with FP. Teeth with GP and MP showed the highest Az values for 8 mA and 10 mA, respectively. For teeth with MP, specificity was significantly higher when 10 mA was used.Conclusions
For teeth without root filling materials or with FP, the use of a reduced milliampere does not seem to influence the detection of VRF in a significant manner. For teeth with GP and MP, an increased milliampere may lead to increased diagnostic performance. 相似文献18.
19.
Daniel Vaz de Souza Elia Schirru Francesco Mannocci Federico Foschi Shanon Patel 《Journal of endodontics》2017,43(1):121-125
Introduction
The aim of this study was to compare the diagnostic efficacy of 2 cone-beam computed tomographic (CBCT) units with parallax periapical (PA) radiographs for the detection and classification of simulated external cervical resorption (ECR) lesions.Methods
Simulated ECR lesions were created on 13 mandibular teeth from 3 human dry mandibles. PA and CBCT scans were taken using 2 different units, Kodak CS9300 (Carestream Health Inc, Rochester, NY) and Morita 3D Accuitomo 80 (J Morita, Kyoto, Japan), before and after the creation of the ECR lesions. The lesions were then classified according to Heithersay's classification and their position on the root surface. Sensitivity, specificity, positive predictive values, negative predictive values, and receiver operator characteristic curves as well as the reproducibility of each technique were determined for diagnostic accuracy.Results
The area under the receiver operating characteristic value for diagnostic accuracy for PA radiography and Kodak and Morita CBCT scanners was 0.872, 0.99, and 0.994, respectively. The sensitivity and specificity for both CBCT scanners were significantly better than PA radiography (P < .001). There was no statistical difference between the sensitivity and specificity of the 2 scanners. The percentage of correct diagnoses according to the tooth type was 87.4% for the Kodak scanner, 88.3% for the Morita scanner, and 48.5% for PA radiography.The ECR lesions were correctly identified according to the tooth surface in 87.8% Kodak, 89.1% Morita and 49.4% PA cases. The ECR lesions were correctly classified according to Heithersay classification in 70.5% of Kodak, 69.2% of Morita, and 39.7% of PA cases.Conclusions
This study revealed that both CBCT scanners tested were equally accurate in diagnosing ECR and significantly better than PA radiography. CBCT scans were more likely to correctly categorize ECR according to the Heithersay classification compared with parallax PA radiographs. 相似文献20.
Junxin Zhu Qiguo Rong Xiaoyan Wang Xuejun Gao 《The Journal of prosthetic dentistry》2017,117(5):646-655