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Llacer-Martínez M, Martín-Biedma B, Sanz MT, Aura-Tormos JI, Fos-Galve P, Fernández-Muñiz Z, Vega JA, Jovani-Sancho M. Cone-Beam Computed Tomography for the Evaluation of Dental Pulp Chamber Volume: Implications for Clinics and Teaching. Dent J (Basel) 2024; 12:95. [PMID: 38668007 PMCID: PMC11049409 DOI: 10.3390/dj12040095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/26/2024] [Accepted: 03/31/2024] [Indexed: 04/28/2024] Open
Abstract
The dental pulp chamber volume is a fundamental measurement in the field of endodontics, but also in forensic sciences, teaching and training, or tissue engineering. This study evaluates the precision of cone-beam computed tomography (CBCT) in comparison with computed micro-tomography (micro-CT) in evaluating the pulp chamber volume of the upper central incisors ex vivo. The intra-operator and inter-operator errors were evaluated, and the results for the two techniques were compared with those of a T-test for paired samples. The intra-operator and inter-operator errors were >0.05, indicating adequate reproducibility in each operator and no significant differences between their measurements. On the other hand, no significant differences between the two measurement techniques were found. The present results demonstrate that CBCT is a precise, feasible, and reproducible technique for the evaluation of the dental pulp chamber volume ex vivo. The results provided with this method are useful for different medical domains but also for the teaching and training of undergraduate and postgraduate students. Furthermore, the findings of this study carry significant clinical implications, as the accurate assessment of the pulp chamber volume is critical in the diagnosis and treatment of various endodontic conditions. The ability of CBCT to provide reliable 3D dental anatomy measurements can enhance the planning of endodontic treatments by allowing for a better understanding of the internal tooth morphology. Additionally, the precision and reproducibility of CBCT in assessing the pulp chamber volume can contribute to improved clinical outcomes and reduced complications during endodontic procedures. These findings further support the increasingly vital role of CBCT in modern clinical practice and underscore its value as an indispensable tool in the field of dentistry.
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Affiliation(s)
- Maria Llacer-Martínez
- Departamento de Odontología, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, 46115 Valencia, Spain; (M.L.-M.); (J.I.A.-T.); (P.F.-G.)
| | - Benjamín Martín-Biedma
- Departamento de Cirugía y Especialidades Médico-Quirúrgicas, Universidad de Santiago de Compostela, 15705 Santiago de Compostela, Spain;
| | - María T. Sanz
- Departamento de Didáctica Matemática, Universidad de Valencia, 46010 Valencia, Spain;
| | - Juan I. Aura-Tormos
- Departamento de Odontología, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, 46115 Valencia, Spain; (M.L.-M.); (J.I.A.-T.); (P.F.-G.)
| | - Pablo Fos-Galve
- Departamento de Odontología, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, 46115 Valencia, Spain; (M.L.-M.); (J.I.A.-T.); (P.F.-G.)
| | | | - José A. Vega
- Departamento de Morfología y Biología Celular, Universidad de Oviedo, 33003 Oviedo, Spain
- Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago de Chile 7500912, Chile
| | - Mar Jovani-Sancho
- Departamento de Odontología, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, 46115 Valencia, Spain; (M.L.-M.); (J.I.A.-T.); (P.F.-G.)
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Intarasuksanti C, Prapayasatok S, Kampan N, Sirabanchongkran S, Mahakkanukrauh P, Sastraruji T, Khongkhunthian P, Kuharattanachai K, Tripuwabhrut K. Effects of the cone-beam computed tomography protocol on the accuracy and image quality of root surface area measurements: An in vitro study. Imaging Sci Dent 2023; 53:325-333. [PMID: 38174039 PMCID: PMC10761297 DOI: 10.5624/isd.20230090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/01/2023] [Accepted: 08/03/2023] [Indexed: 01/05/2024] Open
Abstract
Purpose The objective of this study was to evaluate and compare the accuracy and image quality of root surface area (RSA) measurements obtained with various cone-beam computed tomography (CBCT) protocols, relative to the gold standard of micro-computed tomography (CT), in an in vitro setting. Materials and Methods Four dry human skulls were scanned using 8 different protocols, with voxel sizes of 0.15 mm, 0.3 mm, and 0.4 mm. Three-dimensional models of the selected teeth were constructed using CBCT and micro-CT protocols, and the RSA was automatically measured by the image-processing software. The absolute difference in the percentage of the RSA (%ΔRSA) was calculated and compared across the 8 CBCT protocols using repeated-measures analysis of variance. Finally, image quality scores of the RSA measurements were computed and reported in terms of percent distribution. Results No significant differences were observed in the %ΔRSA across the 8 protocols (P>0.05). The deviation in %ΔRSA ranged from 1.51% to 4.30%, with an increase corresponding to voxel size. As the voxel size increased, the image quality deteriorated. This decline in quality was particularly noticeable at the apical level of the root, where the distribution of poorer scores was most concentrated. Conclusion Relative to CBCT protocols with voxel sizes of 0.15 mm and 0.3 mm, the protocols with a voxel size of 0.4 mm demonstrated inferior image quality at the apical levels. In spite of this, no significant discrepancies were observed in RSA measurements across the different CBCT protocols.
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Affiliation(s)
- Chanikarn Intarasuksanti
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Sangsom Prapayasatok
- Division of Oral and Maxillofacial Radiology, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Natnicha Kampan
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Supassara Sirabanchongkran
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Pasuk Mahakkanukrauh
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Excellence in Osteology Research and Training Center, Chiang Mai University, Chiang Mai, Thailand
| | - Thanapat Sastraruji
- Dental Research Center, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Pathawee Khongkhunthian
- Center of Excellence for Dental Implantology, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Kachaphol Kuharattanachai
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Kanich Tripuwabhrut
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
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3D segmentation of dental crown for volumetric age estimation with CBCT imaging. Int J Legal Med 2023; 137:123-130. [PMID: 36197526 PMCID: PMC9816244 DOI: 10.1007/s00414-022-02898-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/19/2022] [Indexed: 01/11/2023]
Abstract
In adult dental age estimation, segmentation of dental volumetric information from different tooth parts using cone-beam computed tomography (CBCT) has proven beneficial in improving the regression model reliability. This segmentation method can be expanded in the crown part since the volumetric information in the crown is affected by attrition in the enamel and secondary dentine in the dentine and pulp chamber. CBCT scans from 99 patients aged between 20 and 60 were collected retrospectively. A total of 80 eligible teeth for each tooth type were used in this study. The enamel to dentine volume ratio (EDVR), pulp to dentine volume ratio (PDVR) and sex were used as independent variables to predict chronological age (CA). The EDVR was not affected by PDVR. The highest R2 was calculated from the maxillary canine (R2 = 0.6). The current approach in crown segmentation has proven to improve model performance in anterior maxillary teeth.
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Muacevic A, Adler JR. Comparative Evaluation of Orthodontically-Induced Root Resorption Using Cone Beam Computed Tomography (CBCT) and Orthopantomogram (OPG) During En-Masse Retraction of Maxillary Anterior Teeth. Cureus 2022; 14:e31219. [PMID: 36505118 PMCID: PMC9729711 DOI: 10.7759/cureus.31219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND/PURPOSE Orthodontically induced apical root resorption is an inescapable consequence of fixed orthodontics. This root resorption causes post-orthodontic complications in some treated cases. To avoid these complications proper diagnosis of the site and amount of resorption is important. The aim of this study was to compare the diagnostic ability of Orthopantomogram (OPG) and Cone Beam Computed Tomography (CBCT) in detecting apical root resorption after en-masse retraction of maxillary anterior teeth in a sample of Saudi Arabian population. MATERIALS AND METHODS The study sample comprised of 30 patients diagnosed with bimaxillary dentoalveolar protrusion. The treatment plan involved extraction of all first premolars followed by en-masse retraction of the anterior teeth. OPG images were obtained at the beginning of treatment and after the end of the retraction phase and a CBCT image were also obtained for the same patient at the same centre other than orthodontic reason like implant placement, temporomandibular joint (TMJ) problems, sleep apnea, etc. after orthodontic treatment completion. The scoring system of Levander and Malmgren was used to assess the degree and severity of root resorption in the maxillary incisors. Dalhbergs error and coefficient of reliability (ICC) were used to calculate the correlation between the two sets of readings. Pearson chi-square test was used to compare the difference in root resorption between OPG and CBCT images. A P-value of <0.05 was considered to be statistically significant. RESULTS No resorption was observed in 39.2% and 16.6% of incisors with OPG and CBCT respectively. Mild resorption was observed in 50% and 66.7% of incisors with OPG and CBCT respectively. Moderate resorption was found in 10% and 15% of incisors with OPG and CBCT respectively. Severe root resorption was found in 0.8% and 1.7% of incisors with OPG and CBCT respectively. Statistically, significant differences were found in both methods of evaluation in all grades of root resorption for all the maxillary incisors (P<0.05). CONCLUSION OPG had consistently underestimated the amount of orthodontically induced apical root resorption when compared to CBCT. OPG is only useful for the primary evaluation of root resorption. CBCT can be used as an adjunct diagnostic tool on a case-to-case basis in patients with moderate to severe root resorption to manage post-orthodontic treatment complications.
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Poudel A, Yasin MS, Ye J, Liu J, Vinel A, Shao S, Shamsaei N. Feature-based volumetric defect classification in metal additive manufacturing. Nat Commun 2022; 13:6369. [PMID: 36289241 PMCID: PMC9606371 DOI: 10.1038/s41467-022-34122-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 10/13/2022] [Indexed: 11/09/2022] Open
Abstract
Volumetric defect types commonly observed in the additively manufactured parts differ in their morphologies ascribed to their formation mechanisms. Using high-resolution X-ray computed tomography, this study analyzes the morphological features of volumetric defects, and their statistical distribution, in laser powder bed fused Ti-6Al-4V. The geometries of three common types of volumetric defects; i.e., lack of fusions, gas-entrapped pores, and keyholes, are quantified by nine parameters including maximum dimension, roundness, sparseness, aspect ratio, and more. It is shown that the three defect types share overlaps of different degrees in the ranges of their morphological parameters; thus, employing only one or two parameters cannot uniquely determine a defect's type. To overcome this challenge, a defect classification methodology incorporating multiple morphological parameters has been proposed. In this work, by employing the most discriminating parameters, this methodology has been shown effective when implemented into decision tree (>98% accuracy) and artificial neural network (>99% accuracy).
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Affiliation(s)
- Arun Poudel
- grid.252546.20000 0001 2297 8753National Center for Additive Manufacturing Excellence (NCAME), Auburn University, Auburn, AL 36849 USA ,grid.252546.20000 0001 2297 8753Department of Mechanical Engineering, Auburn University, Auburn, AL 36849 USA
| | - Mohammad Salman Yasin
- grid.252546.20000 0001 2297 8753National Center for Additive Manufacturing Excellence (NCAME), Auburn University, Auburn, AL 36849 USA ,grid.252546.20000 0001 2297 8753Department of Mechanical Engineering, Auburn University, Auburn, AL 36849 USA
| | - Jiafeng Ye
- grid.252546.20000 0001 2297 8753Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 36849 USA
| | - Jia Liu
- grid.252546.20000 0001 2297 8753Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 36849 USA
| | - Aleksandr Vinel
- grid.252546.20000 0001 2297 8753Department of Industrial and Systems Engineering, Auburn University, Auburn, AL 36849 USA
| | - Shuai Shao
- grid.252546.20000 0001 2297 8753National Center for Additive Manufacturing Excellence (NCAME), Auburn University, Auburn, AL 36849 USA ,grid.252546.20000 0001 2297 8753Department of Mechanical Engineering, Auburn University, Auburn, AL 36849 USA
| | - Nima Shamsaei
- grid.252546.20000 0001 2297 8753National Center for Additive Manufacturing Excellence (NCAME), Auburn University, Auburn, AL 36849 USA ,grid.252546.20000 0001 2297 8753Department of Mechanical Engineering, Auburn University, Auburn, AL 36849 USA
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Kraaij S, Brand HS, van der Meij EH, de Visscher JG. Relationship between volume of submandibular salivary stones in vivo determined with Cone-Beam Computer Tomography and in vitro with micro-Computer Tomography. Med Oral Patol Oral Cir Bucal 2021; 26:e598-e601. [PMID: 34415002 PMCID: PMC8412442 DOI: 10.4317/medoral.24605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/14/2021] [Indexed: 11/24/2022] Open
Abstract
Background Successful removal of salivary stones depends on exact pretreatment information of the location, the size and shape of the stones. This study aimed to compare the volume of submandibular sialoliths determined by preoperative Cone-Beam Computer Tomography (CBCT) scans with the volume of the removed stones on micro-Computer Tomography (micro-CT) scans. Material and Methods In this study, using twenty-one submandibular sialoliths, the pretreatment volumes in-vivo measured on CBCT were compared to the volumes of removed stones determined by micro-CT scans. The volume measured on micro-CT scans served as the gold standard. Pre-operative CBCT’s and in-vitro micro-CT’s were converted into standard tessellation language models (STL-models) using an image segmentation software package. The CBCT and micro-CT images of the stones were subsequently metrologically assessed and compared to each other using reverse engineering software. Results Volumes of submandibular sialoliths determined by CBCT’s correlated significantly with volumes measured on micro-CT’s (Spearman’s coefficient r = 0.916). The interquartile range (IQR) for the volume measured with micro-CT was 117.23. The median is 26.41. For the volume measured with CBCT the IQR was 141.3 and the median 36.61. The average volume on micro-CT is smaller than on CBCT. Conclusions When using CBCT-scans for the detection of submandibular sialoliths one should realize that in-vivo those stones are actually a fraction smaller than assessed on the preoperative scan. This is important when cut-off values of sizes of stones are used in the pretreatment planning of stone removal. Key words:Salivary stone, sialolith, CBCT, micro-CT, volume.
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Affiliation(s)
- S Kraaij
- Department of Oral Biochemistry Academic Centre for Dentistry Amsterdam (ACTA), room 12N-37 Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
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Effects of Exposure Parameters and Voxel Size for Cone-Beam Computed Tomography on the Image Matching Accuracy with an Optical Dental Scan Image: An In Vitro Study. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6971828. [PMID: 34222482 PMCID: PMC8213486 DOI: 10.1155/2021/6971828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 06/02/2021] [Indexed: 11/17/2022]
Abstract
This study is aimed at assessing the effects of exposure parameters and voxel size for cone-beam computed tomography (CBCT) on the image matching accuracy with an optical dental scan image. CBCT and optical scan images of a dry human mandible were obtained. Different CBCT settings were used: tube voltage, 60, 80, and 100 kVp; tube current, 6 and 8 mA; and voxel size, 100, 200, and 300 μm. Image matching between the CBCT and optical scan images was performed using implant planning software by dental professionals (n = 18). The image matching accuracy in each combination of CBCT settings was evaluated by assessing the linear discrepancy between the three-dimensionally reconstructed radiological image and the registered optical scan image using an image analysis software program. The Kruskal-Wallis test and a post hoc Mann–Whitney U test with Bonferroni correction were used to compare the accuracy of image registration between the groups (α = 0.05). Overall, the image matching accuracy was not significantly different between tube voltage and current settings; however, significantly higher image registration errors were found at the combination of 100 kVp tube voltage/8 mA tube current (F = 8.44, P < 0.001). Changes in voxel sizes did not significantly interfere with the image registration results. No interaction was found among voltage, current, and voxel size in terms of image registration accuracy (F = 2.022, P = 0.091). Different exposure parameter settings in tube voltage and tube current did not significantly influence the image matching accuracy between CBCT and optical dental scan images; however, a high radiation dose could be inappropriate. The image matching accuracy was not significantly affected by changing the voxel sizes of CBCT.
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Koç A, Kaya S. Is it possible to estimate volume of bone defects formed on dry sheep mandibles more practically by secondarily reconstructing section thickness of cone beam computed tomography images? Dentomaxillofac Radiol 2021; 50:20200400. [PMID: 33035111 DOI: 10.1259/dmfr.20200400] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The purpose of this study was to evaluate the effect of section thickness on volume estimations of bone defects scanned using cone beam computed tomography (CBCT). METHODS 25 bone defects were prepared on sheep mandibles and scanned using a KaVo 3D eXam (KaVo Dental, Biberach, Germany) CBCT device. Section thickness of images were reconstructed at 0.25, 0.5, and 0.75 mm to estimate the volume of these defects using the semiautomatic segmentation method. The volume averages obtained using microcomputed tomography and Archimedes' method served as reference values. The estimated volumes at each section thickness were compared with the actual volumes using the Friedman test. The accuracy of volume estimation was determined by the percentage error with respect to the reference values, and the mean absolute error (MAE) was calculated. RESULTS Volumetric values of bone defects obtained with CBCT at section thicknesses up to 0.5 mm were compatible with the actual volumes (p > 0.05). The percentage errors at section thicknesses of 0.25, 0.5, and 0.75 mm were -5.4%, -7.3%, and -13.1%, respectively. The mean absolute errors were 13.6 mm3, 15.7 mm3, and 18.2 mm3, respectively. CONCLUSIONS The section thickness values of CBCT images can be increased to a reasonable level to obtain accurate volume estimation results and save time. The semiautomatic segmentation method can be used reliably for volume estimations of bone defects.
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Affiliation(s)
- Alaettin Koç
- Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Van Yüzüncü Yıl University, Van, Turkey
| | - Sema Kaya
- Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Van Yüzüncü Yıl University, Van, Turkey
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Kazmi S, Shepherd S, Revie G, Hector M, Mânica S. Exploring the relationship between age and the pulp and tooth size in canines. A CBCT analysis. AUST J FORENSIC SCI 2021. [DOI: 10.1080/00450618.2021.1882567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Shakeel Kazmi
- Dundee Dental School, University of Dundee, Dundee, UK
| | | | - Gavin Revie
- Dundee Dental School, University of Dundee, Dundee, UK
| | - Mark Hector
- Dundee Dental School, University of Dundee, Dundee, UK
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Luenam S, Bantuchai T, Kosiyatrakul A, Chanpoo M, Phakdeewisetkul K, Puncreobutr C. Precision of computed tomography and cartilage-reproducing image reconstruction method in generating digital model for potential use in 3D printing of patient-specific radial head prosthesis: a human cadaver study. 3D Print Med 2021; 7:3. [PMID: 33507428 PMCID: PMC7842042 DOI: 10.1186/s41205-021-00093-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 01/10/2021] [Indexed: 11/28/2022] Open
Abstract
Background A prosthetic replacement is a standard treatment for an irreparable radial head fracture; however, the surface mismatch of the commercially available designs is concerned for the long-term cartilage wear. The patient-specific implant created from 3D printing technology could be favorable in replicating the normal anatomy and possibly reduce such sequela. Our study aimed to assess the precision of the computed tomography (CT) and cartilage-reproducing image reconstruction method (CIRM) in generating digital models for potentially use in manufacturing the patient-specific prosthesis from 3D printing. Methods Eight intact elbows (3 right and 5 left) from 7 formalin-embalmed cadavers (4 males and 3 females) with mean age of 83 years (range, 79–94 years) were used for this study. Computerized 3D models were generated from CT, and CIRM. The cartilage-reproducing image reconstruction method has compensated the cartilage profile based on the distance between the subchondral surfaces of the radial head and surrounding bones in CT images. The models of actual radial head geometry used as the gold standard was generated from CT arthrography (CTA). All models of each specimen were matched by registering the surface area of radial neck along with the tuberosity. The difference of head diameter, head thickness, and articular disc depth among three models was evaluated and analyzed by Friedman ANOVA and multiple comparison test using Bonferroni method for statistical correction. A p-value of less than 0.01 was considered statistically significant. The difference of overall 3D geometry was measured with the root mean square of adjacent point pairs. Results The analysis displayed the difference of diameter, thickness, and disc depth across the models (p< 0.01). Pairwise comparisons revealed statistically significant difference of all parameters between CTA models and CT models (p< 0.01) whereas no difference was found between CTA models and CIRM models. The mean difference of overall 3D geometry between CTA models and CT models was 0.51±0.24 mm, and between CTA models and CIRM models was 0.24±0.10 mm. Conclusions CIRM demonstrated encouraging results in reestablish the normal anatomy and could be potentially used in production process of 3D printed patient-specific radial head prosthesis.
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Affiliation(s)
- Suriya Luenam
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand.
| | - Theeraset Bantuchai
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand
| | - Arkaphat Kosiyatrakul
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand
| | - Malee Chanpoo
- Department of Anatomy, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | | | - Chedtha Puncreobutr
- Advanced Materials Analysis Research Unit, Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
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Nilsen BW, Mouhat M, Jokstad A. Quantification of porosity in composite resins delivered by injectable syringes using X-ray microtomography. Biomater Investig Dent 2020; 7:86-95. [PMID: 33458692 PMCID: PMC7782768 DOI: 10.1080/26415275.2020.1784013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Objective To assess whether composite polymer resin delivered in compules include pores and the possible effect on the amount of porosity in dental restorations. Method and materials Original compules containing unpolymerised composite polymer resin (CPR) were scanned in a micro-CT. Four products were examined, which comprised universal composites (Herculite XRV Ultra, Ceram.X Universal, Tetric Evo Ceram) and a flowable bulk-fill composite (SDR) (n = 10 per group). The pore size distribution and amount of porosity (vol.%) were estimated for the unpolymerized and polymerized material used to restore a standardised cavity in a typodont tooth. Manufacturers’ instructions were followed regarding material handling, and polymerisation by use of a calibrated light-curing unit. The pore characteristics and their size distribution, and the amount of porosity in the dental restoration were contrasted with the values measured in the compule. Non-parametric tests were used to analyse differences between the four products. Results All the composite polymer resin compules contained unpolymerised material that included pores. The universal composite compules included pores predominantly in the sub-100 µm sizes. In contrast, the flowable bulk-fill compules included a few pores with a diameter >100 µm, which were assumed to be air-bubbles. The unpolymerised material within the compule included consistently more pores compared to the extruded portion from the compule tip, and in the final restoration (p < .001). The amount of porosity in the restorations differed amongst the tested materials, with the flowable bulk-fill composite showing the lowest amount of porosity (p < .01).
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Affiliation(s)
- Bo Wold Nilsen
- Department of Clinical Dentistry, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Mathieu Mouhat
- Department of Clinical Dentistry, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Asbjørn Jokstad
- Department of Clinical Dentistry, UiT - The Arctic University of Norway, Tromsø, Norway
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Kato CDNADO, Barra SG, Amaral TMP, Silva TA, Abreu LG, Brasileiro CB, Mesquita RA. Cone-beam computed tomography analysis of cemento-osseous dysplasia-induced changes in adjacent structures in a Brazilian population. Clin Oral Investig 2020; 24:2899-2908. [PMID: 32076867 DOI: 10.1007/s00784-019-03154-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 11/11/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVES To describe the effects of cemento-osseous dysplasia (COD) on anatomical structures. METHODS CBCT scans were retrospectively selected from a database of individuals who attended an Oral Medicine service. Cases with a confirmed diagnosis of periapical, focal, or florid COD were included. Two oral and maxillofacial radiologists assessed the scans. Frequencies of the variables were described according to COD case, lesion areas, and teeth. RESULTS Sixty COD cases affected 244 areas and 426 teeth. Florid COD was the most common (n = 48). Cortical bone (buccal, lingual, palatine, or mandibular) (n = 42) and the maxillary sinus (n = 13) were the structures most frequently affected by displacement or perforation. Thinning (n = 80), expansion (n = 62), and perforation (n = 60) of the cortical bone were common effects. The median size of the lesions was 12 mm in the mesiodistal direction, 8 mm in the buccal-lingual/palatal direction, and 9 mm in the superior-inferior direction. Root resorption was observed in 18.1% of all teeth, while tooth displacement was uncommon (0.6%). All teeth affected by COD had a discontinuous lamina dura and non-uniformly visible periodontal ligament space. CONCLUSIONS CBCT images revealed that cortical bone, lamina dura, and periodontal ligament space were the structures most affected by COD and the effects of COD on anatomical structures were more frequent than previously described. CLINICAL RELEVANCE CODs are fibro-osseous lesions common in the clinical practice, and relationship with anatomical structures is poorly described. CBCT is an appropriate method for the diagnosis and follow-up of patients with COD.
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Affiliation(s)
- Camila de Nazaré Alves de Oliveira Kato
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil.
| | - Sâmila Gonçalves Barra
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Tânia Mara Pimenta Amaral
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Tarcília Aparecida Silva
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Lucas Guimarães Abreu
- Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Cláudia Borges Brasileiro
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Ricardo Alves Mesquita
- Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil
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Muhammad AMA, Ibrahim N, Ahmad R, Asif MK, Radzi Z, Zaini ZM, Razak HRA. Effect of reconstruction parameters on cone beam CT trabecular bone microstructure quantification in sheep. BMC Oral Health 2020; 20:48. [PMID: 32041589 PMCID: PMC7011540 DOI: 10.1186/s12903-020-1035-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/04/2020] [Indexed: 11/12/2022] Open
Abstract
Background Cone Beam Computed Tomography (CBCT) is a reliable radiographic modality to assess trabecular bone microarchitecture. The aim of this study was to determine the effect of CBCT image reconstruction parameters, namely, the threshold value and reconstruction voxel size, on trabecular bone microstructure assessment. Methods Five sectioned maxilla of adult Dorper male sheep were scanned using a CBCT system with a resolution of 76 μm3 (Kodak 9000). The CBCT images were reconstructed using different reconstruction parameters and analysed. The effect of reconstruction voxel size (76, 100 and 200 μm3) and threshold values (±15% from the global threshold value) on trabecular bone microstructure measurement was assessed using image analysis software (CT analyser version 1.15). Results There was no significant difference in trabecular bone microstructure measurement between the reconstruction voxel sizes, but a significant difference (Tb.N = 0.03, Tb.Sp = 0.04, Tb.Th = 0.01, BV/TV = 0.00) was apparent when the global threshold value was decreased by 15%. Conclusions Trabecular bone microstructure measurements are not compromised by changing the CBCT reconstruction voxel size. However, measurements can be affected when applying a threshold value of less than 15% of the recommended global value.
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Affiliation(s)
- Aso Muhammad Ali Muhammad
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Norliza Ibrahim
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Rohana Ahmad
- Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh Campus, Jalan Hospital 47000 Sungai Buloh, Shah Alam, Selangor, Malaysia
| | - Muhammad Khan Asif
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Zamri Radzi
- Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Zuraiza Mohamad Zaini
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
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Park JY, Kim D, Han SS, Yu HS, Cha JY. Three-dimensional comparison of 2 digital models obtained from cone-beam computed tomographic scans of polyvinyl siloxane impressions and plaster models. Imaging Sci Dent 2020; 49:257-263. [PMID: 31915610 PMCID: PMC6941835 DOI: 10.5624/isd.2019.49.4.257] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/19/2019] [Accepted: 08/30/2019] [Indexed: 11/18/2022] Open
Abstract
Purpose This study was performed to evaluate the dimensional accuracy of digital dental models constructed from cone-beam computed tomographic (CBCT) scans of polyvinyl siloxane (PVS) impressions and cast scan models. Materials and Methods A pair of PVS impressions was obtained from 20 subjects and scanned using CBCT (resolution, 0.1 mm). A cast scan model was constructed by scanning the gypsum model using a model scanner. After reconstruction of the digital models, the mesio-distal width of each tooth, inter-canine width, and inter-molar width were measured, and the Bolton ratios were calculated and compared. The 2 models were superimposed and the difference between the models was measured using 3-dimensional analysis. Results The range of mean error between the cast scan model and the CBCT scan model was −0.15 mm to 0.13 mm in the mesio-distal width of the teeth and 0.03 mm to 0.42 mm in the width analysis. The differences in the Bolton ratios between the cast scan models and CBCT scan models were 0.87 (anterior ratio) and 0.72 (overall ratio), with no significant difference (P>0.05). The mean maxillary and mandibular difference when the cast scan model and the CBCT scan model were superimposed was 53 µm. Conclusion There was no statistically significant difference in most of the measurements. The maximum tooth size difference was 0.15 mm, and the average difference in model overlap was 53 µm. Digital models produced by scanning impressions at a high resolution using CBCT can be used in clinical practice.
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Affiliation(s)
- Jin-Yi Park
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea
| | - Dasomi Kim
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea
| | - Sang-Sun Han
- Department of Oral and Maxillofacial Radiology, College of Dentistry, Yonsei University, Seoul, Korea
| | - Hyung-Seog Yu
- Department of Orthodontics, Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea
| | - Jung-Yul Cha
- Department of Orthodontics, Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea
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15
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Verhelst PJ, Shaheen E, de Faria Vasconcelos K, Van der Cruyssen F, Shujaat S, Coudyzer W, Salmon B, Swennen G, Politis C, Jacobs R. Validation of a 3D CBCT-based protocol for the follow-up of mandibular condyle remodeling. Dentomaxillofac Radiol 2019; 49:20190364. [PMID: 31674794 PMCID: PMC7068073 DOI: 10.1259/dmfr.20190364] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES Three-dimensional models of mandibular condyles provide a way for condylar remodeling follow-up. The overall aim was to develop and validate a user-friendly workflow for cone beam CT (CBCT)-based semi-automatic condylar registration and segmentation. METHODS A rigid voxel-based registration (VBR) technique for registration of two post-operative CBCT-scans was tested. Two modified mandibular rami, with or without gonial angle, were investigated as the volume of interest for registration. Inter- and intraoperator reproducibility of this technique was tested on 10 mandibular rami of orthognathic patients by means of intraclass correlation coefficients (ICC's) and descriptive statistics of the transformation values from the VBR. The difference in reproducibility between the two modified rami was evaluated using a paired t-test (p < 0.05). For the segmentation, eight fresh frozen cadaver heads were scanned with CBCT and micro-CT. These data were used to test the inter- and intraoperator reproducibility (ICC's) and accuracy (Bland-Altman plot) of a newly designed workflow based on semi-automated contour enhancement. RESULTS Excellent ICC's (0.94-0.99) were obtained for the voxel-based registration technique using both modified rami. If the gonial angle was not included in the volume of interest, there was a trend of increased operator error suggested by significant higher interoperator differences in translation values (p = 0,0036). The segmentation workflow proved to be highly reproducible with excellent ICC's (0.99), low absolute mean volume differences between operators (23.19 mm3), within operators (28.93 mm3) and low surface distances between models of different operators (<0.20 mm). Regarding the accuracy, CBCT-models slightly overestimate the condylar volume compared to micro-CT. CONCLUSIONS This study provides a validated user-friendly and reproducible method of creating three-dimensional-surface models of mandibular condyles out of longitudinal CBCT-scans.
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Affiliation(s)
- Pieter-Jan Verhelst
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Eman Shaheen
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Karla de Faria Vasconcelos
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - Fréderic Van der Cruyssen
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Sohaib Shujaat
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - Walter Coudyzer
- Department of Radiology, University Hospitals Leuven, Leuven, Belgium
| | - Benjamin Salmon
- Orofacial Pathologies, Imaging and Biotherapies EA2496 Lab, University of Paris, Montrouge, France.,Dental Medicine Department, AP-HP, Bretonneau Hospital, Paris, France
| | - Gwen Swennen
- Division of Maxillofacial Surgery, Department of Surgery, AZ Sint-Jan Brugge-Oostende AV, Bruges, Belgium
| | - Constantinus Politis
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Reinhilde Jacobs
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium.,Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden
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16
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Eliliwi M, Bazina M, Palomo JM. kVp, mA, and voxel size effect on 3D voxel-based superimposition. Angle Orthod 2019; 90:269-277. [PMID: 31549857 DOI: 10.2319/012719-52.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVES To evaluate the effect of changing kVp, mA, and voxel size on the accuracy of voxel-based superimposition on the anterior cranial base. MATERIALS AND METHODS Cone beam computed tomography (CBCT) scans were taken on a phantom skull using different kVp, mA, and voxel size combinations. CBCT scans were superimposed using commercially available software. Two separate open-source software programs were used to generate a three-dimensional (3D) color map objective assessment of the differences in seven different regions: Nasion, Point A, Zygomatic (right and left), Point B, and Gonial (right and left). Each region had around 200 points that were used to calculate the mean differences between the superimpositions. RESULTS Intraclass correlation showed excellent reliability (0.95). Lowering the kVp made the biggest difference, showing an average discrepancy of 0.7 ± 0.3 mm, and a high mean of 1.4 ± 0.3 in the Right Gonial region. Lowering the mA showed less of a discrepancy, with an average of 0.373 ± 0.2 mm, and the highest discrepancy, also on the Right Gonial Area, of 0.7 ± 0.1 mm. The voxel size had the least impact on the accuracy of registered volumes, with mean discrepancy values of less than 0.2 mm. CONCLUSIONS Using different CBCT settings can affect the accuracy of the voxel-based superimposition method. This is particularly the case when using low kVp values, while changes in mA or voxel sizes did not significantly interfere with the superimposition outcome.
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17
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Andrade VM, Fontenele RC, de Souza AC, Almeida CAD, Vieira AC, Groppo FC, Freitas DQ, Junior ED. Age and sex estimation based on pulp cavity volume using cone beam computed tomography: development and validation of formulas in a Brazilian sample. Dentomaxillofac Radiol 2019; 48:20190053. [PMID: 31322923 DOI: 10.1259/dmfr.20190053] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To develop and validate formulas for age and sex estimation based on the pulp cavity volume of teeth using cone beam CT. METHODS The sample was composed of 116 cone beam CT scans from Brazilian individuals of both sexes, ranging in age from 13 to 70 years. A total of 232 teeth (upper central incisors and canines) were evaluated. Two calibrated examiners determined pulp cavity volumes using the ITK-SNAP software. Pearson's correlation test was used to assess the correlation between chronological age and pulp volume. Linear and logistic regression models were developed for age and sex estimation, respectively, and were validated in another sample of 72 teeth. RESULTS Pearson's correlation coefficients between age and pulp volume were negative and significant (p < 0.0001) for both teeth (r = -0.8782 for central incisors and r = -0.8738 for canines). The age estimation formulas showed good determination coefficients (adjusted R² = 0.7614 to 0.8367). For sex estimation, when the age was known, the coefficients were also good (adjusted R² = 0.649 to 0.812). However, when the age was unknown, the coefficients of the sex estimation formulas were low (adjusted R² = 0.047 to 0.393). Validation showed high accuracy of age estimation in individuals older than 35 years, as well as high accuracy of sex estimation when the age was known. CONCLUSIONS Our formulas provided excellent results and can be applied to the Brazilian population. The best results were observed for age estimation in females and for sex estimation when the age was known.
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Affiliation(s)
- Vanessa M Andrade
- Forensic Odontology Service, Afrânio Peixoto Legal Medicine Institute, Rio de Janeiro, Brazil.,Department of Social Odontology, Legal Odontology Division, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
| | - Rocharles C Fontenele
- Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
| | - Andreia Cb de Souza
- Forensic Odontology Service, Afrânio Peixoto Legal Medicine Institute, Rio de Janeiro, Brazil.,Department of Social and Preventive Dentistry, Dentistry College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Casimiro Ap de Almeida
- Department of Social and Preventive Dentistry, Dentistry College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Andrea Cd Vieira
- Department of Pathology and Oral Diagnosis, Radiology Service, Dentistry College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Francisco C Groppo
- Department of Physiological Sciences, Area of Pharmacology, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
| | - Deborah Q Freitas
- Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
| | - Eduardo D Junior
- Department of Social Odontology, Legal Odontology Division, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
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Mohara NT, Coelho MS, de Queiroz NV, Borreau MLS, Nishioka MM, de Jesus Soares A, Frozoni M. Root Anatomy and Canal Configuration of Maxillary Molars in a Brazilian Subpopulation: A 125-μm Cone-Beam Computed Tomographic Study. Eur J Dent 2019; 13:82-87. [PMID: 31170761 PMCID: PMC6635971 DOI: 10.1055/s-0039-1688736] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Objective
Knowledge of internal anatomy of the teeth is of great importance in endodontics, leading to success in root canal therapy (RCT). The aim of this study was to assess the root anatomy and canal configuration of maxillary molars in a Brazilian subpopulation using tomographic images using a voxel size of 125 μm.
Materials and Methods
This in vivo retrospective study assessed 651 cone-beam computed tomographic scans from 328 maxillary first molars and 323 maxillary second molars. The images were assessed by two endodontists and an oral radiologist. Only permanent molars with fully developed roots and with no signs of RCT were included.
Results
Maxillary first and second molars presented three separated roots in 99.39 and 90.09% of the cases, respectively. The presence of mesiolingual canals in the mesiobuccal roots was 64.22% for maxillary first molars and 33.56% for maxillary second molars. Distobuccal canals in the maxillary first and second molars presented Vertucci's Type I configuration in 99.39 and 99.66%, respectively, and palatal canals in the maxillary first and second molars presented Vertucci's Type I configuration in 99.69 and 99.68%, respectively. Maxillary second molars were more subjected to anatomical variations than first molars. Female patients presented higher prevalence of mesiolingual canals in the maxillary second molars.
Conclusions
The most prevalent morphology in the maxillary first and second molars was three root canals. The presence of only one or two roots is more likely to occur in the maxillary second molars than in the maxillary first molars. Mesiolingual canals in mesiobuccal roots are more frequent in the maxillary first molars than in the maxillary second molars, and the occurrence of two distobuccal or two palatal canals is rare.
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Affiliation(s)
- Nelson Tsutomu Mohara
- Department of Endodontics, São Leopoldo Mandic School of Dentistry, Campinas, SP, Brazil
| | - Marcelo Santos Coelho
- Department of Endodontics, São Leopoldo Mandic School of Dentistry, Campinas, SP, Brazil
| | | | | | | | | | - Marcos Frozoni
- Department of Endodontics, São Leopoldo Mandic School of Dentistry, Campinas, SP, Brazil
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Computed Tomography versus Optical Scanning: A Comparison of Different Methods of 3D Data Acquisition for Tooth Replication. BIOMED RESEARCH INTERNATIONAL 2019; 2019:4985121. [PMID: 31093500 PMCID: PMC6481121 DOI: 10.1155/2019/4985121] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 03/05/2019] [Accepted: 04/01/2019] [Indexed: 12/13/2022]
Abstract
Objectives The study aimed to compare the accuracy of different methods of data acquisition and data reconstruction and to assess their usefulness for 3D printing of tooth replicas. Methods 3-dimensional models of molar and canine teeth obtain utilizing CBCT examination with different protocols, and optical scanning was compared with models derived from micro-computed (micro-CT) examination using Geomagic Studio Qualify software. A pairwise comparison of 3D models with analysis of standard deviation and the value of the mean distance of given surfaces was performed. Results Standard deviation and the value of the mean distance were lowest for optical scanning followed by CBC in high and standard resolution in all tested protocols. Models, obtained with high-resolution CBCT protocols, of teeth in and outside of alveolar bone showed similar average distance parameters, but standard deviation parameter was significantly lower for models of teeth scanned outside of the socket. Good surface representation on all models was seen at relatively smooth areas while in areas of high changes in the geometry CBCT based models performed inferiorly to those obtained from an optical scanner. Conclusions In case of teeth of noncomplicated texture, independently from a position (within or outside the alveolar socket), the high-resolution CBCT seems to be a sufficient method to obtain data for 3D printed tooth replica. Optical scanning performs better when a detailed replica is necessary.
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Shokri A, Jamalpour MR, Eskandarloo A, Godiny M, Amini P, Khavid A. Performance of Cone Beam Computed Tomography Systems in Visualizing the Cortical Plate in 3D Image Reconstruction: An In Vitro Study. Open Dent J 2018; 12:586-595. [PMID: 30288182 PMCID: PMC6142658 DOI: 10.2174/1874210601812010586] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 06/29/2018] [Accepted: 08/10/2018] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Cortical bone is an important anatomical structure and its thickness needs to be determined prior to many dental procedures to ensure treatment success. Imaging modalities are necessarily used in dentistry for treatment planning and dental procedures. Three-dimensional image reconstruction not only provides visual information but also enables accurate measurement of anatomical structures; thus, it is necessarily required for maxillofacial examination and in case of skeletal problems in this region. AIMS This study aimed to assess the ability of three Cone Beam Computed Tomography (CBCT) systems including Cranex 3D, NewTom 3G and 3D Promax for Three-Dimensional (3D) image reconstruction of the cortical plate with variable thicknesses. METHODS Depending on the cortical bone thickness, samples were evaluated in three groups of ≤ 0. 5 mm, 0.6 -1 mm and 1.1-1.5 mm cortical bone thickness. The CBCT scans were obtained from each sample using three systems, their respective FOVs, and 3D scans were reconstructed using their software programs. Two observers viewed the images twice with a two-week interval. The ability of each system in the 3D reconstruction of different thicknesses of cortical bone was determined based on its visualization on the scans. The data were analyzed using SPSS and Kappa test. RESULTS The three systems showed the greatest difference in the 3D reconstruction of cortical bone with < 0.5 mm thickness. Cranex 3D with 4×6 cm2 FOV had the highest and 3D Promax with 8×8 cm2 FOV had the lowest efficacy for 3D reconstruction of cortical bone. Cranex 3D with 4×6 cm2 and 6×8 cm2 FOVs and NewTom 3G with 5×5 cm2 and 8×5 cm2 FOVs showed significantly higher efficacy for 3D reconstruction of cortical bone with 0.6-1mm thickness while 3D Promax followed by NewTom 3G with 8×8 cm2 FOV had the lowest efficacy for this purpose. CONCLUSION Most CBCT systems have high efficacy for 3D image reconstruction of cortical bone with thicknesses over 1 mm while they have poor efficacy for image reconstruction of cortical bone with less than 0.5 mm thickness. Thus, for accurate visualization of anatomical structures on CBCT scans, systems with smaller FOVs and consequently smaller voxel size are preferred.
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Affiliation(s)
- Abbas Shokri
- Department of Oral and Maxillofacial Radiology, Dental Research Center, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mohammad Reza Jamalpour
- Department of Oral and Maxillofacial Radiology, Dental Research Center, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Amir Eskandarloo
- Department of Oral and Maxillofacial Radiology, Dental School, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mostafa Godiny
- Department of Endodontics, Dental school , Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Payam Amini
- Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Atefeh Khavid
- Department of Oral and Maxillofacial Radiology, Dental School, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Wang C, Liu Y, Wang S, Wang Y, Zhao Y. Evaluation of in vivo digital root reconstruction based on anatomical characteristics of the periodontal ligament using cone beam computed tomography. Sci Rep 2018; 8:269. [PMID: 29321613 PMCID: PMC5762886 DOI: 10.1038/s41598-017-18592-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 12/14/2017] [Indexed: 11/09/2022] Open
Abstract
This study's aim was to develop and validate an approach to automatically extract and reconstruct three-dimensional (3D) digital root models from in vivo teeth based on the anatomical characteristics of the periodontal ligament using cone beam computed tomography (CBCT) data. Prior to undergoing dental extractions for orthodontic purposes, the CBCT data of each study participant were collected and imported into Mimics software to reconstruct 3D in vivo digital root models (test models). Twenty roots of 17 teeth extracted from the study's participants were scanned using a dental scanner to obtain 3D in vitro digital root models (reference models). The 3D morphological deviation between the reference and test models was compared; the 3D size of the bucco-lingual, mesio-distal, and root length dimensions were calculated. This approach achieved an average 3D morphological deviation of 0.21 mm, and the average size error in the bucco-lingual, mesio-distal, and root length dimensions were -0.35 mm, -0.17 mm, and 0.47 mm, respectively. This new automatic extraction approach rapidly and accurately reconstructs 3D in vivo root models with detailed morphological information, and has the potential to improve diagnostic and treatment work flow in orthodontic clinics, as well as in other areas of dentistry.
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Affiliation(s)
- Chenxin Wang
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing Shi, China
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing Shi, China
- National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Shi, China
- Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Shi, China
- Beijing Key Laboratory of Digital Stomatology, Beijing Shi, China
| | - Yi Liu
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing Shi, China
- National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Shi, China
- Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Shi, China
- Beijing Key Laboratory of Digital Stomatology, Beijing Shi, China
| | - Siwei Wang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing Shi, China
- National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Shi, China
- Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Shi, China
- Beijing Key Laboratory of Digital Stomatology, Beijing Shi, China
| | - Yong Wang
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing Shi, China
- National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Shi, China
- Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Shi, China
- Beijing Key Laboratory of Digital Stomatology, Beijing Shi, China
| | - Yijiao Zhao
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing Shi, China.
- National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Shi, China.
- Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Shi, China.
- Beijing Key Laboratory of Digital Stomatology, Beijing Shi, China.
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22
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Galibourg A, Dumoncel J, Telmon N, Calvet A, Michetti J, Maret D. Assessment of automatic segmentation of teeth using a watershed-based method. Dentomaxillofac Radiol 2017; 47:20170220. [PMID: 28937285 DOI: 10.1259/dmfr.20170220] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Tooth 3D automatic segmentation (AS) is being actively developed in research and clinical fields. Here, we assess the effect of automatic segmentation using a watershed-based method on the accuracy and reproducibility of 3D reconstructions in volumetric measurements by comparing it with a semi-automatic segmentation(SAS) method that has already been validated. METHODS The study sample comprised 52 teeth, scanned with micro-CT (41 µm voxel size) and CBCT (76; 200 and 300 µm voxel size). Each tooth was segmented by AS based on a watershed method and by SAS. For all surface reconstructions, volumetric measurements were obtained and analysed statistically. Surfaces were then aligned using the SAS surfaces as the reference. The topography of the geometric discrepancies was displayed by using a colour map allowing the maximum differences to be located. RESULTS AS reconstructions showed similar tooth volumes when compared with SAS for the 41 µm voxel size. A difference in volumes was observed, and increased with the voxel size for CBCT data. The maximum differences were mainly found at the cervical margins and incisal edges but the general form was preserved. CONCLUSION Micro-CT, a modality used in dental research, provides data that can be segmented automatically, which is timesaving. AS with CBCT data enables the general form of the region of interest to be displayed. However, our AS method can still be used for metrically reliable measurements in the field of clinical dentistry if some manual refinements are applied.
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Affiliation(s)
- Antoine Galibourg
- 1 Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, Toulouse, France.,2 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France
| | - Jean Dumoncel
- 1 Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, Toulouse, France
| | - Norbert Telmon
- 1 Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, Toulouse, France.,3 Service de Médecine Légale, Hôpital de Rangueil, Toulouse, France
| | - Adèle Calvet
- 1 Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, Toulouse, France.,4 Faculté de médecine, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France
| | - Jérôme Michetti
- 2 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France
| | - Delphine Maret
- 1 Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université Paul Sabatier, Toulouse, France.,2 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France
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da Silva NC, Barriviera M, Junqueira JLC, Panzarella FK, Raitz R. Intraobserver and interobserver reproducibility in linear measurements on axial images obtained by cone-beam computed tomography. Imaging Sci Dent 2017; 47:11-15. [PMID: 28361024 PMCID: PMC5370249 DOI: 10.5624/isd.2017.47.1.11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/02/2016] [Accepted: 10/31/2016] [Indexed: 11/18/2022] Open
Abstract
PURPOSE This study was performed to investigate the intra- and inter-observer variability in linear measurements with axial images obtained by PreXion (PreXion Inc., San Mateo, USA) and i-CAT (Imaging Sciences International, Xoran Technologies Inc., Hatfield, USA) CBCT scanners, with different voxel sizes. MATERIALS AND METHODS A cylindrical object made from nylon with radiopaque markers (phantom) was scanned by i-CAT and PreXion 3D devices. For each axial image, measurements were taken twice in the horizontal (distance A-B) and vertical (distance C-D) directions, randomly, with a one-week interval between measurements, by four oral radiologists with five years or more experience in the use of these measuring tools. RESULTS All of the obtained linear measurements had lower values than those of the phantom. The statistical analysis showed high intra- and inter-observer reliability (p=0.297). Compared to the real measurements, the measurements obtained using the i-CAT device and PreXion tomography, on average, revealed absolute errors ranging from 0.22 to 0.59 mm and from 0.23 to 0.63 mm, respectively. CONCLUSION It can be concluded that both scanners are accurate, although the linear measurements are underestimations, with no significant differences between the evaluators.
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Affiliation(s)
- Nathália Cristine da Silva
- São Leopoldo Mandic Research Center, Department of Oral Radiology, College of Dentistry, São Paulo, SP, Brazil
| | - Maurício Barriviera
- Department of Oral Radiology, College of Dentistry, Catholic University of Brasilia, São Paulo, SP, Brazil
| | - José Luiz Cintra Junqueira
- São Leopoldo Mandic Research Center, Department of Oral Radiology, College of Dentistry, São Paulo, SP, Brazil
| | - Francine Kühl Panzarella
- São Leopoldo Mandic Research Center, Department of Oral Radiology, College of Dentistry, São Paulo, SP, Brazil
| | - Ricardo Raitz
- São Leopoldo Mandic Research Center, Department of Oral Radiology, College of Dentistry, São Paulo, SP, Brazil
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Dindaroğlu F, Doğan S. Root Resorption in Orthodontics. Turk J Orthod 2016; 29:103-108. [PMID: 30112483 DOI: 10.5152/turkjorthod.2016.16021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 11/23/2016] [Indexed: 12/27/2022]
Abstract
Root resorption has been the subject of many studies, and it can be caused by many factors such as the mechanics used during orthodontic treatment, factors related to the type and magnitude of the force, and other factors related to treatment such as the type of tooth movement and malocclusion. The clinical importance of root resorption is directly related to its detectability. Therefore, orthodontic and biological factors that may cause root resorption were evaluated using various imaging methods in present use. In this review, root resorption in orthodontics was considered from different viewpoints.
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Affiliation(s)
- Furkan Dindaroğlu
- Department of Orthodontics, Ege University School of Dentistry, İzmir, Turkey
| | - Servet Doğan
- Department of Orthodontics, Ege University School of Dentistry, İzmir, Turkey
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25
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The impact of manual threshold selection in medical additive manufacturing. Int J Comput Assist Radiol Surg 2016; 12:607-615. [PMID: 27718124 PMCID: PMC5362669 DOI: 10.1007/s11548-016-1490-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 09/27/2016] [Indexed: 11/24/2022]
Abstract
Purpose Medical additive manufacturing requires standard tessellation language (STL) models. Such models are commonly derived from computed tomography (CT) images using thresholding. Threshold selection can be performed manually or automatically. The aim of this study was to assess the impact of manual and default threshold selection on the reliability and accuracy of skull STL models using different CT technologies. Method One female and one male human cadaver head were imaged using multi-detector row CT, dual-energy CT, and two cone-beam CT scanners. Four medical engineers manually thresholded the bony structures on all CT images. The lowest and highest selected mean threshold values and the default threshold value were used to generate skull STL models. Geometric variations between all manually thresholded STL models were calculated. Furthermore, in order to calculate the accuracy of the manually and default thresholded STL models, all STL models were superimposed on an optical scan of the dry female and male skulls (“gold standard”). Results The intra- and inter-observer variability of the manual threshold selection was good (intra-class correlation coefficients >0.9). All engineers selected grey values closer to soft tissue to compensate for bone voids. Geometric variations between the manually thresholded STL models were 0.13 mm (multi-detector row CT), 0.59 mm (dual-energy CT), and 0.55 mm (cone-beam CT). All STL models demonstrated inaccuracies ranging from −0.8 to +1.1 mm (multi-detector row CT), −0.7 to +2.0 mm (dual-energy CT), and −2.3 to +4.8 mm (cone-beam CT). Conclusions This study demonstrates that manual threshold selection results in better STL models than default thresholding. The use of dual-energy CT and cone-beam CT technology in its present form does not deliver reliable or accurate STL models for medical additive manufacturing. New approaches are required that are based on pattern recognition and machine learning algorithms.
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Soft tissue coverage on the segmentation accuracy of the 3D surface-rendered model from cone-beam CT. Clin Oral Investig 2016; 21:921-930. [PMID: 27206862 PMCID: PMC5360826 DOI: 10.1007/s00784-016-1844-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 05/02/2016] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The aim of this study is to investigate the effect of soft tissue presence on the segmentation accuracy of the 3D hard tissue models from cone-beam computed tomography (CBCT). MATERIALS AND METHODS Seven pairs of CBCT Digital Imaging and Communication in Medicine (DICOM) datasets, containing data of human cadaver heads and their respective dry skulls, were used. The effect of the soft tissue presence on the accuracy of the segmented models was evaluated by performing linear and angular measurements and by superimposition and color mapping of the surface discrepancies after splitting the mandible and maxillo-facial complex in the midsagittal plane. RESULTS The linear and angular measurements showed significant differences for the more posterior transversal measurements on the mandible (p < 0.01). By splitting and superimposing the maxillo-facial complex, the mean root-mean-square error (RMSE) as a measurement of inaccuracy decreased insignificantly from 0.936 to 0.922 mm (p > 0.05). The RMSE value for the mandible, however, significantly decreased from 1.240 to 0.981 mm after splitting (p < 0.01). CONCLUSIONS The soft tissue presence seems to affect the accuracy of the 3D hard tissue model obtained from a cone-beam CT, below a generally accepted level of clinical significance of 1 mm. However, this level of accuracy may not meet the requirement for applications where high precision is paramount. CLINICAL RELEVANCE Accuracy of CBCT-based 3D surface-rendered models, especially of the hard tissues, are crucial in several dental and medical applications, such as implant planning and virtual surgical planning on patients undergoing orthognathic and navigational surgeries. When used in applications where high precision is paramount, the effect of soft tissue presence should be taken into consideration during the segmentation process.
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Matzen LH, Wenzel A. Efficacy of CBCT for assessment of impacted mandibular third molars: a review - based on a hierarchical model of evidence. Dentomaxillofac Radiol 2015; 44:20140189. [PMID: 25135317 DOI: 10.1259/dmfr.20140189] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
A radiographic examination of mandibular third molars is meant to support the surgeon in establishing a treatment plan. For years panoramic (PAN) imaging has been the first choice method; however, where an overprojection is observed between the third molar and the mandibular canal and when specific signs suggest a close contact between the molar and the canal, CBCT may be indicated. The present review provides an evaluation of the efficacy of CBCT for assessment of mandibular third molars using a six-tiered hierarchical model by Fryback and Thornbury in 1991. Levels 1-3 include studies on low evidence levels mainly regarding the technical capabilities of a radiographic method and the diagnostic accuracy of the related images. Levels 4-6 include studies on a higher level of evidence and assess the diagnostic impact of a radiographic method on the treatment of the patient in addition to the outcome for the patient and society including cost calculations. Only very few high-evidence studies on the efficacy of CBCT for radiographic examination of mandibular third molars exist and, in conclusion, periapical or PAN examination is sufficient in most cases before removal of mandibular third molars. However, CBCT may be suggested when one or more signs for a close contact between the tooth and the canal are present in the two-dimensional image-if it is believed that CBCT will change the treatment or the treatment outcome for the patient. Further research on high-evidence levels is needed.
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Affiliation(s)
- L H Matzen
- Section of Oral Radiology, Department of Dentistry, Aarhus University, Aarhus, Denmark
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Michetti J, Georgelin-Gurgel M, Mallet JP, Diemer F, Boulanouar K. Influence of CBCT parameters on the output of an automatic edge-detection-based endodontic segmentation. Dentomaxillofac Radiol 2015; 44:20140413. [PMID: 26119343 DOI: 10.1259/dmfr.20140413] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To determine the optimal CBCT settings for an automatic edge-detection-based endodontic segmentation procedure by assessing the accuracy of the root canal measurements. METHODS 12 intact teeth with closed apexes were cut perpendicular to the root axis, at pre-determined levels to the reference plane (the first section made before acquisition). Acquisitions of each specimen were performed with Kodak 9000(®) 3D (76 µm, 14 bits; Kodak Carestream Health, Trophy, France) by using different combinations of milliamperes and kilovolts. Three-dimensional images were displayed and root canals were segmented with the MeVisLab software (edge-detection-based method; MeVis Research, Bremen, Germany). Histological root canal sections were then digitized with a 0.5- to 1.0-µm resolution and compared with equivalent two-dimensional cone-beam reconstructions for each pair of settings using the Pearson correlation coefficient, regression analysis and Bland-Altman method for the canal area and Feret's diameter. After a ranking process, a Wilcoxon paired test was carried out to compare the pair of settings. RESULTS The best pair of acquisition settings was 3.2 mA/60 kV. Significant differences were found between 3.2 mA/60 kV and other settings (p < 0.05) for the root canal area and for Feret's diameter. CONCLUSIONS The quantitative analyses of the root canal system with the edge-detection-based method could depend on acquisition parameters. Improvements in segmentation still need to be carried out to ensure the quality of the reconstructions when we have to deal with closer outlines and because of the low spatial resolution.
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Affiliation(s)
- J Michetti
- 1 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France.,2 Laboratoire INSERM, Imagerie Cérébrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire, Toulouse, France
| | - M Georgelin-Gurgel
- 1 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France.,3 Laboratoire des Déficiences, Incapacités et Désavantages en Santé Orale, EA4847, Université d'Auvergne, Clermont-Ferrand, France
| | - J-P Mallet
- 1 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France
| | - F Diemer
- 1 Faculté de Chirurgie Dentaire, Université Paul Sabatier, Centre Hospitalier Universitaire, Toulouse, France.,4 Group SUMO, Institut Clément Ader, Toulouse, France
| | - K Boulanouar
- 2 Laboratoire INSERM, Imagerie Cérébrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire, Toulouse, France
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Vallaeys K, Kacem A, Legoux H, Le Tenier M, Hamitouche C, Arbab-Chirani R. 3D dento-maxillary osteolytic lesion and active contour segmentation pilot study in CBCT: semi-automatic vs manual methods. Dentomaxillofac Radiol 2015; 44:20150079. [PMID: 25996572 DOI: 10.1259/dmfr.20150079] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVES This study was designed to evaluate the reliability of a semi-automatic segmentation tool for dento-maxillary osteolytic image analysis compared with manually defined segmentation in CBCT scans. METHODS Five CBCT scans were selected from patients for whom periapical radiolucency images were available. All images were obtained using a ProMax® 3D Mid Planmeca (Planmeca Oy, Helsinki, Finland) and were acquired with 200-μm voxel size. Two clinicians performed the manual segmentations. Four operators applied three different semi-automatic procedures. The volumes of the lesions were measured. An analysis of dispersion was made for each procedure and each case. An ANOVA was used to evaluate the operator effect. Non-paired t-tests were used to compare semi-automatic procedures with the manual procedure. Statistical significance was set at α = 0.01. RESULTS The coefficients of variation for the manual procedure were 2.5-3.5% on average. There was no statistical difference between the two operators. The results of manual procedures can be used as a reference. For the semi-automatic procedures, the dispersion around the mean can be elevated depending on the operator and case. ANOVA revealed significant differences between the operators for the three techniques according to cases. CONCLUSIONS Region-based segmentation was only comparable with the manual procedure for delineating a circumscribed osteolytic dento-maxillary lesion. The semi-automatic segmentations tested are interesting but are limited to complex surface structures. A methodology that combines the strengths of both methods could be of interest and should be tested. The improvement in the image analysis that is possible through the segmentation procedure and CBCT image quality could be of value.
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Affiliation(s)
- K Vallaeys
- 1 UFR d'Odontologie, Université de Bretagne Occidentale, Brest, France.,2 Laboratoire de Traitement de I'Information Médicale, LaTim-Inserm UMR 1101, Brest, France.,3 Service d'Odontologie, Centre Hospitalier Régional Universitaire Brest, France
| | - A Kacem
- 2 Laboratoire de Traitement de I'Information Médicale, LaTim-Inserm UMR 1101, Brest, France.,4 Départment Image et Traitement de I'Information, Telecom Bretagne, Brest, France.,5 Institut National des Sciences Appliquées et de Technologies de Tunis, INSAT, Tunis, Tunisia
| | - H Legoux
- 1 UFR d'Odontologie, Université de Bretagne Occidentale, Brest, France.,3 Service d'Odontologie, Centre Hospitalier Régional Universitaire Brest, France
| | - M Le Tenier
- 1 UFR d'Odontologie, Université de Bretagne Occidentale, Brest, France.,3 Service d'Odontologie, Centre Hospitalier Régional Universitaire Brest, France
| | - C Hamitouche
- 2 Laboratoire de Traitement de I'Information Médicale, LaTim-Inserm UMR 1101, Brest, France.,4 Départment Image et Traitement de I'Information, Telecom Bretagne, Brest, France
| | - R Arbab-Chirani
- 1 UFR d'Odontologie, Université de Bretagne Occidentale, Brest, France.,2 Laboratoire de Traitement de I'Information Médicale, LaTim-Inserm UMR 1101, Brest, France.,3 Service d'Odontologie, Centre Hospitalier Régional Universitaire Brest, France
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Forst D, Nijjar S, Flores-Mir C, Carey J, Secanell M, Lagravere M. Comparison of in vivo 3D cone-beam computed tomography tooth volume measurement protocols. Prog Orthod 2014; 15:69. [PMID: 25534123 PMCID: PMC4274349 DOI: 10.1186/s40510-014-0069-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 12/03/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The objective of this study is to analyze a set of previously developed and proposed image segmentation protocols for precision in both intra- and inter-rater reliability for in vivo tooth volume measurements using cone-beam computed tomography (CBCT) images. METHODS Six 3D volume segmentation procedures were proposed and tested for intra- and inter-rater reliability to quantify maxillary first molar volumes. Ten randomly selected maxillary first molars were measured in vivo in random order three times with 10 days separation between measurements. Intra- and inter-rater agreement for all segmentation procedures was attained using intra-class correlation coefficient (ICC). RESULTS The highest precision was for automated thresholding with manual refinements. CONCLUSIONS A tooth volume measurement protocol for CBCT images employing automated segmentation with manual human refinement on a 2D slice-by-slice basis in all three planes of space possessed excellent intra- and inter-rater reliability. Three-dimensional volume measurements of the entire tooth structure are more precise than 3D volume measurements of only the dental roots apical to the cemento-enamel junction (CEJ).
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Affiliation(s)
| | | | | | | | | | - Manuel Lagravere
- Department of Dentistry, University of Alberta, Edmonton Clinic Health Academy, 5th Floor, 11405 - 87 Avenue NW, Edmonton T6G 1C9, Alberta, Canada.
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Spin-Neto R, Gotfredsen E, Wenzel A. Impact of voxel size variation on CBCT-based diagnostic outcome in dentistry: a systematic review. J Digit Imaging 2014; 26:813-20. [PMID: 23254628 DOI: 10.1007/s10278-012-9562-7] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The objective of this study was to make a systematic review on the impact of voxel size in cone beam computed tomography (CBCT)-based image acquisition, retrieving evidence regarding the diagnostic outcome of those images. The MEDLINE bibliographic database was searched from 1950 to June 2012 for reports comparing diverse CBCT voxel sizes. The search strategy was limited to English-language publications using the following combined terms in the search strategy: (voxel or FOV or field of view or resolution) and (CBCT or cone beam CT). The results from the review identified 20 publications that qualitatively or quantitatively assessed the influence of voxel size on CBCT-based diagnostic outcome, and in which the methodology/results comprised at least one of the expected parameters (image acquisition, reconstruction protocols, type of diagnostic task, and presence of a gold standard). The diagnostic task assessed in the studies was diverse, including the detection of root fractures, the detection of caries lesions, and accuracy of 3D surface reconstruction and of bony measurements, among others. From the studies assessed, it is clear that no general protocol can be yet defined for CBCT examination of specific diagnostic tasks in dentistry. Rationale in this direction is an important step to define the utility of CBCT imaging.
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Affiliation(s)
- Rubens Spin-Neto
- Department of Dentistry-Oral Radiology Health, Aarhus University, Vennelyst Boulevard 9, Aarhus C, 8000 Aarhus, Denmark.
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A Bone-Thickness Map as a Guide for Bone-Anchored Port Implantation Surgery in the Temporal Bone. MATERIALS 2013; 6:5291-5301. [PMID: 28788390 PMCID: PMC5452769 DOI: 10.3390/ma6115291] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 10/20/2013] [Accepted: 11/11/2013] [Indexed: 11/17/2022]
Abstract
The bone-anchored port (BAP) is an investigational implant, which is intended to be fixed on the temporal bone and provide vascular access. There are a number of implants taking advantage of the stability and available room in the temporal bone. These devices range from implantable hearing aids to percutaneous ports. During temporal bone surgery, injuring critical anatomical structures must be avoided. Several methods for computer-assisted temporal bone surgery are reported, which typically add an additional procedure for the patient. We propose a surgical guide in the form of a bone-thickness map displaying anatomical landmarks that can be used for planning of the surgery, and for the intra-operative decision of the implant’s location. The retro-auricular region of the temporal and parietal bone was marked on cone-beam computed tomography scans and tridimensional surfaces displaying the bone thickness were created from this space. We compared this method using a thickness map (n = 10) with conventional surgery without assistance (n = 5) in isolated human anatomical whole head specimens. The use of the thickness map reduced the rate of Dura Mater exposition from 100% to 20% and suppressed sigmoid sinus exposures. The study shows that a bone-thickness map can be used as a low-complexity method to improve patient’s safety during BAP surgery in the temporal bone.
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Ibrahim N, Parsa A, Hassan B, van der Stelt P, Aartman IHA, Wismeijer D. The effect of scan parameters on cone beam CT trabecular bone microstructural measurements of the human mandible. Dentomaxillofac Radiol 2013; 42:20130206. [PMID: 24132024 DOI: 10.1259/dmfr.20130206] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The objective of this study was to investigate the effect of different cone beam CT scan parameters on trabecular bone microstructure measurements. A human mandibular cadaver was scanned using a cone beam CT (3D Accuitomo 170; J.Morita, Kyota, Japan). 20 cone beam CT images were obtained using 5 different fields of view (4×4 cm, 6×6 cm, 8×8 cm, 10×10 cm and 10×5 cm), 2 types of rotation steps (180° and 360°) and 2 scanning resolutions (standard and high). Image analysis software was used to assess the trabecular bone microstructural parameters (number, thickness and spacing). All parameters were measured twice by one trained observer. Intraclass correlation coefficients showed high intraobserver repeatability (intraclass correlation coefficient, 0.95-0.97) in all parameters across all tested scan parameters. Trabecular bone microstructural measurements varied significantly, especially in smaller fields of view (p = 0.001). There was no significant difference in the trabecular parameters when using different resolutions (number, p = 0.988; thickness, p = 0.960; spacing, p = 0.831) and rotation steps (number, p = 1.000; thickness, p = 0.954; spacing, p = 0.759). The scan field of view significantly influences the trabecular bone microstructure measurements. Rotation steps (180° or 360°) and resolution (standard or high) selections are not relevant.
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Affiliation(s)
- N Ibrahim
- Department of General and Specialized Dentistry, Section of Oral and Maxillofacial Radiology, Academic Center for Dentistry Amsterdam (ACTA), Amsterdam, Netherlands
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Ye N, Jian F, Lai W. Effect of voxel size and partial volume effect on accuracy of tooth volumetric measurements with cone beam CT. Dentomaxillofac Radiol 2013; 42:20130070. [PMID: 23604055 DOI: 10.1259/dmfr.20130070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Zekry A, Wang R, Chau ACM, Lang NP. Facial alveolar bone wall width - a cone-beam computed tomography study in Asians. Clin Oral Implants Res 2013; 25:194-206. [PMID: 23294441 DOI: 10.1111/clr.12096] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2012] [Indexed: 11/29/2022]
Affiliation(s)
- Ahmed Zekry
- Faculty of Dentistry, The Prince Philip Dental Hospital; The University of Hong Kong; Hong Kong SAR China
| | - Ren Wang
- Faculty of Dentistry, The Prince Philip Dental Hospital; The University of Hong Kong; Hong Kong SAR China
| | - Anson C. M. Chau
- Faculty of Dentistry, The Prince Philip Dental Hospital; The University of Hong Kong; Hong Kong SAR China
| | - Niklaus P. Lang
- Faculty of Dentistry, The Prince Philip Dental Hospital; The University of Hong Kong; Hong Kong SAR China
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