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Weissheimer A, Pham J, Tong H, Akyalcin S. Esthetic outcomes in orthodontics through digital customization with a lingual appliance system. J ESTHET RESTOR DENT 2024; 36:1267-1280. [PMID: 38716890 DOI: 10.1111/jerd.13244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 04/17/2024] [Accepted: 04/21/2024] [Indexed: 08/11/2024]
Abstract
BACKGROUND Contemporary fixed orthodontic appliances are shifting from non-customized pre-adjusted appliances to custom-designed and printed appliances with novel digital setup systems. We are one step closer to precision dentistry and orthodontics using personalized mechanics and custom appliances. However, despite the evidential enhancement and other improvements to fixed appliances, tooth movement is still limited to five degrees of freedom. Opening or closing spaces still requires manually placing elastomeric chains or coil springs. AIM In this article, we aimed to demonstrate how advancements in CAD/CAM technology, reverse engineering, and digital customization are helping orthodontics constantly evolve, enabling treatment with enhanced esthetics and minimal compliance. The clinical system (InBrace®, Irvine, CA) described in this article uses a patient-specific, digitally designed multiloop NITI wire that delivers friction-free, light, and continuous forces and activates automatically whenever the malocclusion deviates from the digital setup. CONCLUSION Through digital customization, InBrace allows for automated tooth movement in all six degrees of freedom, including space opening or closure, via programmed non-sliding mechanics. CLINICAL SIGNIFICANCE Precision orthodontics and personalized treatment have been significant developments in orthodontics recently. This article focuses on how a technologically advanced lingual appliance system could achieve targeted cosmetic results methodically via automation and personalization.
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Affiliation(s)
- Andre Weissheimer
- Department of Developmental Biology, Harvard School of Dental Medicine, Boston, USA
| | - John Pham
- Senior Medical Scientist for InBrace, Irvine, USA
| | - Hongsheng Tong
- Postgraduate Orthodontics Program, University of Southern California, Los Angeles, USA
| | - Sercan Akyalcin
- Department of Developmental Biology, Harvard School of Dental Medicine, Boston, USA
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2
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Dai F, Sang Y, Zeng J, Wang H, Pan Y, Zhao J, Xu T, Shu G. How accurate is predicted root movement achieved in four first-premolar extraction cases with Invisalign? Orthod Craniofac Res 2024. [PMID: 39137241 DOI: 10.1111/ocr.12842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 07/19/2024] [Accepted: 07/23/2024] [Indexed: 08/15/2024]
Abstract
OBJECTIVES This study aims to compare the achieved and predicted root movements in adults after four first-premolar extractions and Invisalign treatment. MATERIALS AND METHODS Thirty-three consecutive adults (22 Class I, 9 Cusp-to-cusp Class II and 2 Cusp-to-cusp Class III) from a single clinical division who completed the first series of aligners after premolar extractions were included in this retrospective study. A pretreatment cone-beam computed tomography model was registered onto the pretreatment surface-scanned dental model (SSDM) to locate the pretreatment root apices of the whole dentition. These were copied and transferred to the predicted and achieved post-treatment SSDMs to acquire the locations of the predicted and achieved post-treatment root apices. The differences between predicted and achieved root movements (DPARMs) were tested using the paired t-test or Wilcoxon signed rank test. RESULTS In the anteroposterior direction, posterior root movements of maxillary and mandibular anterior teeth were poorly achieved (3.24-5.74 mm DPARMs, p < .05). In the vertical direction, roots of maxillary anterior teeth achieved greater intrusion (0.70-0.93 mm DPARMs, p < .05), while those of mandibular incisors achieved less intrusion (0.57-0.65 mm DPARMs, p < .05) than predicted. In the mediolateral direction, lateral incisor roots did not move distally (-0.65 to -0.96 mm DPARMs, p < .05), while those of canines did not move buccally, compared with the prediction (-0.75 mm DPARMs, p < .05). CONCLUSIONS In the four first-premolar extraction treatments with Invisalign, root movements were not achieved as predicted, particularly for anterior teeth in the anteroposterior direction.
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Affiliation(s)
- Fanfan Dai
- Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
| | - Yanhui Sang
- Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
| | - Jingjing Zeng
- Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
| | - Hongjian Wang
- Shanghai Bondent Technology Co., Ltd, Shanghai, China
| | - Yichun Pan
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
- Fourth Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
| | - Jianhui Zhao
- Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
| | - Tianmin Xu
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China
| | - Guang Shu
- Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
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Sun D, Wang J, Zuo Z, Jia Y, Wang Y. STS-TransUNet: Semi-supervised Tooth Segmentation Transformer U-Net for dental panoramic image. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2024; 21:2366-2384. [PMID: 38454687 DOI: 10.3934/mbe.2024104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
In this paper, we introduce a novel deep learning method for dental panoramic image segmentation, which is crucial in oral medicine and orthodontics for accurate diagnosis and treatment planning. Traditional methods often fail to effectively combine global and local context, and struggle with unlabeled data, limiting performance in varied clinical settings. We address these issues with an advanced TransUNet architecture, enhancing feature retention and utilization by connecting the input and output layers directly. Our architecture further employs spatial and channel attention mechanisms in the decoder segments for targeted region focus, and deep supervision techniques to overcome the vanishing gradient problem for more efficient training. Additionally, our network includes a self-learning algorithm using unlabeled data, boosting generalization capabilities. Named the Semi-supervised Tooth Segmentation Transformer U-Net (STS-TransUNet), our method demonstrated superior performance on the MICCAI STS-2D dataset, proving its effectiveness and robustness in tooth segmentation tasks.
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Affiliation(s)
- Duolin Sun
- University of Science and Technology of China, Hefei, China
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China
| | - Jianqing Wang
- Hangzhou Sai Future Technology Co., Ltd, Hangzhou, China
| | - Zhaoyu Zuo
- University of Science and Technology of China, Hefei, China
| | - Yixiong Jia
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China
| | - Yimou Wang
- University of Science and Technology of China, Hefei, China
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Thawri SR, Paul P, Reche A, Rathi HP. 3D Technology Used for Precision in Orthodontics. Cureus 2023; 15:e47170. [PMID: 38022318 PMCID: PMC10652056 DOI: 10.7759/cureus.47170] [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: 08/21/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
One of the most crucial technologies used by orthodontists to assess and document the dimensions of craniofacial features is imaging. Orthodontists frequently employ two-dimensional (2D) imaging methods, although 2D imaging cannot localize or determine the depth of structures. Early in the 1990s, three-dimensional (3D) imaging was invented, and it has since become a crucial part of dentistry, especially in orthodontics. One of the newest and most important breakthroughs in dentistry is 3D technology. Clinicians have been able to significantly improve patient care while also shortening the time spent on treatment planning due to these technologies, which include intra-oral scanning, 3D imaging, computed-axial tomography (CAT) scan, cone-beam computed tomography (CBCT), computer-aided design/computer-aided manufacturing (CAD/CAM), and 3D software. 3D models of maxillary and mandibular arches can take the place of conventional plaster casts and their limits for planning treatments, appliance production, and estimated treatment results as part of this continuous progress. Digital orthodontics procedures have become more popular in the recent past. The development of "personalized" orthodontic appliances makes use of technology. These technologies' overall improvement can increase clinicians' productivity and efficiency by simplifying traditional methods that are seen to be particularly laborious. The objectives of this review are to provide an overall description of the 3D technology nowadays and to assess its orthodontic applications.
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Affiliation(s)
- Samiksha R Thawri
- Department of Public Health Dentistry, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research (Deemed to be University), Wardha, IND
| | - Priyanka Paul
- Department of Public Health Dentistry, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research (Deemed to be University), Wardha, IND
| | - Amit Reche
- Department of Public Health Dentistry, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research (Deemed to be University), Wardha, IND
| | - Harsha P Rathi
- Department of Public Health Dentistry, Sharad Pawar Dental College and Hospital, Datta Meghe Institute of Higher Education and Research (Deemed to be University), Wardha, IND
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Huh J, Liu J, Yu JH, Choi YJ, Ahn HK, Chung CJ, Cha JY, Kim KH. Three-dimensional evaluation of a virtual setup considering the roots and alveolar bone in molar distalization cases. Sci Rep 2023; 13:14955. [PMID: 37696835 PMCID: PMC10495328 DOI: 10.1038/s41598-023-41480-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 08/27/2023] [Indexed: 09/13/2023] Open
Abstract
We aimed to evaluate root parallelism and the dehiscence or fenestrations of virtual teeth setup using roots isolated from cone beam computed tomography (CBCT) images. Sixteen patients undergoing non-extraction orthodontic treatment with molar distalization were selected. Composite teeth were created by merging CBCT-isolated roots with intraoral scan-derived crowns. Three setups were performed sequentially: crown setup considering only the crowns, root setup-1 considering root alignment, and root setup-2 considering the roots and surrounding alveolar bone. We evaluated the parallelism and exposure of the roots and compared the American Board of Orthodontics Objective Grading System (ABO-OGS) scores using three-dimensionally printed models among the setups. The mean angulation differences between adjacent teeth in root setups-1 and -2 were significantly smaller than in the crown setup, except for some posterior teeth (p < 0.05). The amount of root exposure was significantly smaller in root setup-2 compared to crown setup and root setup-1 except when the mean exposure was less than 0.6 mm (p < 0.05). There was no significant difference in ABO-OGS scores among the setups. Thus, virtual setup considering the roots and alveolar bone can improve root parallelism and reduce the risk of root exposure without compromising occlusion quality.
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Affiliation(s)
- Jaewook Huh
- Department of Orthodontics, Yonsei University College of Dentistry, Seoul, Korea
| | - Jing Liu
- Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry, Seoul, Korea
| | - Jae-Hun Yu
- Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry, Seoul, Korea
| | - Yoon Jeong Choi
- Department of Orthodontics, Institute of Craniofacial Deformity, Yonsei University College of Dentistry, Seoul, Korea
| | - Hee-Kap Ahn
- Graduate School of Artificial Intelligence, Department of Computer Science and Engineering, Pohang University of Science and Technology, Pohang, Korea
- Institute for Convergence Research and Education in Advanced Technology, Yonsei University, Seoul, Korea
| | - Chooryung J Chung
- Department of Orthodontics, Institute of Craniofacial Deformity, Gangnam Severance Dental Hospital, College of Dentistry, Yonsei University, Seoul, Korea
| | - Jung-Yul Cha
- Department of Orthodontics, Institute of Craniofacial Deformity, College of Dentistry, Institute for Innovation in Digital Healthcare, Yonsei University, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Korea.
| | - Kyung-Ho Kim
- Department of Orthodontics, Institute of Craniofacial Deformity, Gangnam Severance Dental Hospital, College of Dentistry, Yonsei University, Seoul, Korea.
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Galluccio G, De Stefano AA, Horodynski M, Impellizzeri A, Guarnieri R, Barbato E, Di Carlo S, De Angelis F. Efficacy and Accuracy of Maxillary Arch Expansion with Clear Aligner Treatment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4634. [PMID: 36901642 PMCID: PMC10002100 DOI: 10.3390/ijerph20054634] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
The aim of this work was to evaluate the efficacy and accuracy of maxillary arch transverse expansion using the Invisalign® clear aligner system without auxiliaries other than Invisalign attachments. Knowing the accuracy of a movement through a clear aligner system allows the clinician to plan the treatment with greater precision and to achieve the expected result faster. The study group included 28 patients with a mean age of 17 ± 3.2 years. The treatment protocol for all the selected patients included the application of the Invisalign® clear aligner system without auxiliaries, except for the Invisalign® attachments; in no case were tooth extraction or interproximal enamel reduction (IPR) performed. Linear measurements of the expansion were assessed before treatment (T0), at the end of treatment (T1), and on final virtual models by ClinCheck® (TC). A paired t-test was used to compare T0-T1 and T1-TC differences. A paired t-test was applied, and one normality was validated with the Shapiro-Wilks test. If normality was not met, the nonparametric test (Mann-Whitney U test) was applied. The level of significance was set at 5%. Statistically significant differences were found for all measurements at T0-T1. The results showed an average accuracy of efficacy of 70.88%. The differences in predictability between the various vestibular measurements (intercanine, inter-premolar, and intermolar) were not statistically significant, while they were for gingival measurements. The overall accuracy of the expansion treatment was 70%, regardless of tooth type.
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Park M, Allareddy V, Atsawasuwan P, Lee MK, Lee KC. Consideration of root position in virtual tooth setup for extraction treatment: A comparative study of simulated and actual treatment results. Korean J Orthod 2023; 53:26-34. [PMID: 36696957 PMCID: PMC9877363 DOI: 10.4041/kjod22.105] [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: 04/25/2022] [Revised: 08/18/2022] [Accepted: 09/17/2022] [Indexed: 01/27/2023] Open
Abstract
Objective The purpose of the present study was to compare the root positions in virtual tooth setups using only crowns in a simulated treatment with those achieved in the actual treatment. Methods Pre- and post-treatment intraoral and corresponding cone beam computed tomography (CBCT) scans were obtained from 15 patients who underwent orthodontic treatment with premolar extraction. A conventional virtual tooth setup was used for the treatment simulation. Pre- and post-treatment three-dimensional digital tooth models were fabricated by integrating the patients' intraoral and CBCT scans. The simulated root positions in the virtual setup were obtained by merging the crown in the virtual setup and root in the pre-treatment tooth model. The root positions of the simulated and actual post-treatment tooth models were compared. Results Differences in root positions between the simulated and actual models were > 1 mm in all teeth, and statistically significant differences were observed (p < 0.05), except for the maxillary lateral incisors. The differences in the inter-root angulation were > 1° in all teeth, and statistically significant differences were observed in the maxillary and mandibular canines. Conclusions The virtual tooth setup using only crown data showed errors over the clinical limits. The clinical application of a virtual setup using crowns and roots is necessary for accurate and precise treatment simulation, particularly in extraction treatment.
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Affiliation(s)
- Mirinae Park
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | | | - Phimon Atsawasuwan
- Department of Orthodontics, University of Illinois Chicago, Chicago, IL, USA
| | - Min Kyeong Lee
- Department of Orthodontics, University of Illinois Chicago, Chicago, IL, USA
| | - Kyungmin Clara Lee
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea,Department of Orthodontics, University of Illinois Chicago, Chicago, IL, USA,Corresponding author: Kyungmin Clara Lee. Professor, Department of Orthodontics, School of Dentistry, Chonnam National University 33 Yongbong-ro, Buk-gu, Gwangju 61186, Korea., Tel +82-62-530-5864 e-mail
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Filonenko VV, Kaniura OА, Kopchak AV, Kryshchuk MG. STUDY OF THE STRESS-STRAIN STATE OF THE MAXILLA DURING ORTHODONTIC TREATMENT OF DENTOGNATHIC DEFORMATIONS IN CHILDREN WITH CONGENITAL CLEFT LIP AND PALATE. WIADOMOSCI LEKARSKIE (WARSAW, POLAND : 1960) 2023; 76:2648-2656. [PMID: 38290029 DOI: 10.36740/wlek202312114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
OBJECTIVE The aim: To create a three-dimensional simulation mechanical-mathematical model of the biomechanical system "Orthodontic appliance-maxilla", to study peculiarities of the stress-strained state of the maxilla. PATIENTS AND METHODS Materials and methods: A simulation model of the biomechanical system "Orthodontic appliance-maxilla" was created using computed tomography (CBCT) data. Mathematical modeling was used to determine the stress-strain state of the simulation model. RESULTS Results: The patterns of changes in the stress state were determined and the values of deformation displacements in the structural elements of the biome-chanical system "Orthodontic appliance-maxilla" were determined under a force stress of the orthodontic device with an amplitude of 50 N. CONCLUSION Conclusions: Simulation computer modeling of the stress-strain state of the "Orthodontic appliance-maxilla" system showed that activation of the kinematic mechanism of the appliance with a force of 50 N causes the emergence of a complex stress-strain state of bones. When the orthodontic appliance is activated, there is an asymmetry in the distribution of stresses by Mises between the right and left sides both for the appliance itself and for the maxillary bone tissue.
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Affiliation(s)
| | | | | | - Mykola G Kryshchuk
- NATIONAL TECHNICAL UNIVERSITY OF UKRAINE «IGOR SIKORSKY KYIV POLYTECHNIC INSTITUTE», KYIV, UKRAINE
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Kakehbaraei S, Arvanaghi R, Seyedarabi H, Esmaeili F, Zenouz AT. 3D tooth segmentation in cone-beam computed tomography images using distance transform. Biomed Signal Process Control 2023. [DOI: 10.1016/j.bspc.2022.104122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tong H, Lee RJ, Weissheimer A, Pham J. Orthodontics on autopilot through digital customization and Programmed Non-Sliding Mechanics. J World Fed Orthod 2022; 11:202-206. [PMID: 36369084 DOI: 10.1016/j.ejwf.2022.10.002] [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: 08/15/2022] [Accepted: 10/08/2022] [Indexed: 11/10/2022]
Abstract
Orthodontic tooth movement occurs in six degrees of freedom, which includes opening and closing spaces. Traditionally, opening and closing spaces are achieved with auxiliaries such as power chains or springs because all traditional bracket systems cannot achieve this tooth movement by themselves. The InBrace system has the capability to program tooth movement in all six degrees of freedom, including opening and closing spaces, through digital customization and its use of Programmed Non-Sliding Mechanics.
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Affiliation(s)
- Hongsheng Tong
- Clinical Assistant Professor, Advanced Orthodontic Program, Herman Ostrow School of Dentistry, Los Angeles, California; Co-Founder and Principal Orthodontic Scientist for InBrace, Irvine, California.
| | - Robert J Lee
- Clinical Assistant Professor, Division of Orthodontics, University of California San Francisco, San Francisco, California; Co-Inventor and Senior Clinical Advisor for InBrace, Irvine, California
| | - Andre Weissheimer
- Clinical Assistant Professor, Advanced Orthodontic Program, Herman Ostrow School of Dentistry, Los Angeles, California; Senior Medical Scientist for InBrace, Irvine, California
| | - John Pham
- Co-Founder and Chief Medical Officer for InBrace, Irvine, California
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Pi S, Geng J, Bajestan M, Oberoi S, Lee RJ. Accuracy and reliability of the expected root position setup to evaluate root proximity of an edentulous site. Am J Orthod Dentofacial Orthop 2022; 162:753-762. [PMID: 37830535 DOI: 10.1016/j.ajodo.2022.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 11/17/2022]
Abstract
INTRODUCTION It is important to achieve proper root position during orthodontic treatment involving future dental implant placement. However, current methods to evaluate root position are either inaccurate or expose patients to relatively high radiation levels. A new approach using an expected root position (ERP) setup has previously demonstrated the potential to accurately monitor root position with minimal radiation. This study aimed to evaluate whether the ERP setup is an accurate and reliable method to determine if the roots adjacent to an edentulous site are appropriate for the anticipated dental implant. METHODS In this retrospective study, the ERP setup was generated for 22 edentulous sites selected from the University of California San Francisco Division of Orthodontics patient database. The mesiodistal angulation of all teeth adjacent to the edentulous sites and the mesiodistal space between the teeth were measured in the ERP setup and compared with the posttreatment cone-beam computed tomography (CBCT) scan, which served as the control. The intraoperator and interoperator reliability and agreement between the ERP setup and the posttreatment CBCT scan were assessed using Bland-Altman analysis. The correlation between measurements was further evaluated by the Pearson correlation coefficient. RESULTS The Bland-Altman plots and the Pearson correlation coefficient displayed strong agreement between the ERP setup and the posttreatment CBCT scan, with only 11.4% mesiodistal angulation measurements beyond the clinically acceptable range of ± 2.5°. All mesiodistal angulations and distances were strongly correlated with high intraoperator and interoperator reliabilities. CONCLUSION The method to generate an ERP set up to evaluate the mesiodistal angulation and space of an edentulous site prepared for a future dental implant has been demonstrated to be accurate and reliable.
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Affiliation(s)
- Sarah Pi
- Division of Orthodontics, University of California San Francisco, San Francisco, Calif
| | - Jiaxin Geng
- School of Dentistry, University of California San Francisco, San Francisco, Calif
| | - Mona Bajestan
- Division of Orthodontics, University of California San Francisco, San Francisco, Calif
| | - Snehlata Oberoi
- Department of Orofacial Sciences, University of California San Francisco, San Francisco, Calif
| | - Robert J Lee
- Division of Orthodontics, University of California San Francisco, San Francisco, Calif.
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Lee SC, Hwang HS, Lee KC. Accuracy of deep learning-based integrated tooth models by merging intraoral scans and CBCT scans for 3D evaluation of root position during orthodontic treatment. Prog Orthod 2022; 23:15. [PMID: 35527317 PMCID: PMC9081076 DOI: 10.1186/s40510-022-00410-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 04/12/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Objective
This study aimed to evaluate the accuracy of deep learning-based integrated tooth models (ITMs) by merging intraoral scans and cone-beam computed tomography (CBCT) scans for three-dimensional (3D) evaluation of root position during orthodontic treatment and to compare the fabrication process of integrated tooth models (ITMs) with manual method.
Material and methods
Intraoral scans and corresponding CBCT scans before and after treatment were obtained from 15 patients who completed orthodontic treatment with premolar extraction. A total of 600 ITMs were generated using deep learning technology and manual methods by merging the intraoral scans and CBCT scans at pretreatment. Posttreatment intraoral scans were integrated into the tooth model, and the resulting estimated root positions were compared with the actual root position at posttreatment CBCT. Discrepancies between the estimated and actual root position including average surface differences, arch widths, inter-root distances, and root axis angles were obtained in both the deep learning and manual method, and these measurements were compared between the two methods.
Results
The average surface differences of estimated and actual ITMs in the manual method were 0.02 mm and 0.03 mm for the maxillary and mandibular arches, respectively. In the deep learning method, the discrepancies were 0.07 mm and 0.08 mm for the maxillary and mandibular arches, respectively. For the measurements of arch widths, inter-root distances, and root axis angles, there were no significant differences between estimated and actual models both in the manual and in the deep learning methods, except for some measurements. Comparing the two methods, only three measurements showed significant differences. The procedure times taken to obtain the measurements were longer in the manual method than in the deep learning method.
Conclusion
Both deep learning and manual methods showed similar accuracy in the integration of intraoral scans and CBCT images. Considering time and efficiency, the deep learning automatic method for ITMs is highly recommended for clinical practice.
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Effect of Low-Intensity Pulsed Ultrasound (LIPUS) on Alveolar Bone during Maxillary Expansion Using Clear Aligners. BIOMED RESEARCH INTERNATIONAL 2022; 2022:4505063. [PMID: 35528174 PMCID: PMC9076310 DOI: 10.1155/2022/4505063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/24/2022] [Accepted: 03/26/2022] [Indexed: 11/17/2022]
Abstract
The present study evaluated the possible effect of low-intensity pulsed ultrasound (LIPUS) on buccal bone plate thickness and height after maxillary arch expansion using clear aligners. The cone beam computed tomography (CBCT) of before and immediately after maxillary arch expansion (3 mm per side) of 28 adult patients (18 in LIPUS group and 10 in control) (average age
years old) was analyzed. The wearing protocol of clear aligners in the LIPUS group was to change the aligners every 4 to 5 days, while the wearing protocol in the control group (without LIPUS) was to change the aligners every 7 to 10 days. Bone thickness at 3 mm and 6 mm from the buccal alveolar bone crests, along with the measurements of buccal alveolar bone heights, was measured in standardized sagittal sections. Data were analyzed through paired sample
-test and the Wilcoxon test. The results were given as
and 95% confidence intervals.
value < 0.05 was considered statistically significant. The results showed significant increase in bone height in both groups. However, comparison of both LIPUS and control groups showed no statistically significant difference in bone thickness or bone height. The results of this study showed that the use of LIPUS together with accelerated aligner tray change protocol did not affect alveolar bone integrity when compared to the control group.
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Application of Three-Dimensional Digital Technology in Orthodontics: The State of the Art. Biomimetics (Basel) 2022; 7:biomimetics7010023. [PMID: 35225915 PMCID: PMC8883890 DOI: 10.3390/biomimetics7010023] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/11/2022] [Accepted: 01/24/2022] [Indexed: 12/10/2022] Open
Abstract
Three-dimensional technologies are one of the most recent and relevant advancements in the field of Dentistry. These systems, including intraoral scans, 3D imaging exams (CAT scan, CBCT and MRI), CAD/CAM 3D printing devices and 3D computer software, have enabled clinicians to greatly improve patient care along with reducing treatment planning time. The present descriptive study aims to explore possible applications of 3D technologies during the diagnosis, treatment plan, case monitoring and result assessment in orthodontics. The overall upgrade provided by these technologies can improve the clinicians’ workflow and effectiveness by simplifying conventional techniques considered to be especially arduous.
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Ruetters M, Gehrig H, Kronsteiner D, Weyer V, Kim TS, Lux CJ, Sen S. Ex-vivo imaging of buccal and oral periodontal bone with low-dose CBCT in porcine jaws. Dentomaxillofac Radiol 2022; 51:20210233. [PMID: 34233504 PMCID: PMC8693329 DOI: 10.1259/dmfr.20210233] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES New CBCT devices have been developed which can provide "low-dose CBCTs (LD-CBCT)". Aim of this study is to investigate the suitability of LD-CBCT for measurement of alveolar buccal/oral bone. METHODS AND MATERIALS Vestibular and oral bone loss of the teeth of seven porcine mandibles free of soft tissues were investigated by Micro-CT and three CBCT-modes: high-dose (HD), standard-dose (SD) and low-dose (LD). Radiographic measurements of bone loss (bl) and vestibular and oral bone thickness (bt) were made by two raters at 69 sites. Measurement means and differences, Intraclass correlation (ICC) and Bland-Altman plots were calculated. RESULTS ICCs between raters(r) concerning bl were 0.954 for HD, 0.949 for SD and 0.945 for LD; concerning bt they were 0.872 for HD, 0.845 for SD and 0.783 for LD. Means of differences of bt measurements were -0.01 mm(r1)/0.00 mm(r2) for HD, 0.04 mm(r1)/0.02 mm(r2) for SD and 0.02 mm(r1)/0.04 mm(r2) for LD; for bl measurements they were 0.06 mm(r1)/0.05 mm(r2) for HD, -0.01 mm(r1)/0.13 mm(r2) for SD and 0.07 mm(r1)/0.16 mm(r2) for LD.Linear regression indicates no noticeable differences between methods and the raters with respect to bl and bt. CONCLUSIONS Relating to the CBCT-device used in this study, LD-CBCT is a promising method to detect and describe buccal and oral periodontal bl and bt. Further studies with human anatomic structures must confirm these results.
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Affiliation(s)
- Maurice Ruetters
- Section of Periodontology, Department of Operative Dentistry, University Hospital Heidelberg, Germany Im Neuenheimer Feld, Heidelberg, Germany
| | - Holger Gehrig
- Section of Periodontology, Department of Operative Dentistry, University Hospital Heidelberg, Germany Im Neuenheimer Feld, Heidelberg, Germany
| | - Dorohtea Kronsteiner
- Institute of Medical Biometry, University Hospital Heidelberg Im Neuenheimer Feld, Heidelberg, Germany
| | | | - Ti-Sun Kim
- Section of Periodontology, Department of Operative Dentistry, University Hospital Heidelberg, Germany Im Neuenheimer Feld, Heidelberg, Germany
| | - Christopher J. Lux
- Department of Orthodontics, University Hospital Heidelberg, Germany Im Neuenheimer Feld, Heidelberg, Germany
| | - Sinan Sen
- Department of Orthodontics, University Hospital Heidelberg, Germany Im Neuenheimer Feld, Heidelberg, Germany
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16
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Dot G, Licha R, Goussard F, Sansalone V. A new protocol to accurately track long-term orthodontic tooth movement and support patient-specific numerical modeling. J Biomech 2021; 129:110760. [PMID: 34628204 DOI: 10.1016/j.jbiomech.2021.110760] [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: 02/12/2021] [Revised: 09/15/2021] [Accepted: 09/18/2021] [Indexed: 10/20/2022]
Abstract
Numerical simulation of long-term orthodontic tooth movement based on Finite Element Analysis (FEA) could help clinicians to plan more efficient and mechanically sound treatments. However, most of FEA studies assume idealized loading conditions and lack experimental calibration or validation. The goal of this paper is to propose a novel clinical protocol to accurately track orthodontic tooth displacement in three-dimensions (3D) and provide 3D models that may support FEA. Our protocol uses an initial cone beam computed tomography (CBCT) scan and several intra-oral scans (IOS) to generate 3D models of the maxillary bone and teeth ready for use in FEA. The protocol was applied to monitor the canine retraction of a patient during seven months. A second CBCT scan was performed at the end of the study for validation purposes. In order to ease FEA, a frictionless and statically determinate lingual device for maxillary canine retraction was designed. Numerical simulations were set up using the 3D models provided by our protocol to show the relevance of our proposal. Comparison of numerical and clinical results highlights the suitability of this protocol to support patient-specific FEA.
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Affiliation(s)
- Gauthier Dot
- Univ Paris Est Creteil, CNRS, MSME, F-94010, Creteil, France; Univ Gustave Eiffel, MSME, F-77474, Marne-la-Vallée, France; Service d'Odontologie, Hopital Pitie-Salpetriere, AP-HP, Universite de Paris, Paris, France
| | - Raphael Licha
- Univ Paris Est Creteil, CNRS, MSME, F-94010, Creteil, France; Univ Gustave Eiffel, MSME, F-77474, Marne-la-Vallée, France
| | - Florent Goussard
- CR2P, UMR 7207, Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, 8 rue Buffon, CP38 75005, Paris, France
| | - Vittorio Sansalone
- Univ Paris Est Creteil, CNRS, MSME, F-94010, Creteil, France; Univ Gustave Eiffel, MSME, F-77474, Marne-la-Vallée, France.
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17
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A Digital Approach to Evaluating Tooth Root Position Without Repeated Cone-beam Computed Tomography Scans. J Craniofac Surg 2021; 33:e347-e349. [PMID: 34347718 DOI: 10.1097/scs.0000000000008058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
ABSTRACT The purpose of this report is to introduce a digital approach to evaluating three-dimensional root position without radiation using virtual tooth model which is composed of intraoral-scanned crown and cone-beam computed tomography (CBCT)-scanned root. Successful treatment depends not only on the formulation of a proper initial diagnosis, but also on an accurate assessment of treatment progress, which should include the monitoring and evaluation of tooth and root movements. Although CBCT allows the visualization of the true root position and angulation in three-dimensions, the obtaining of serial CBCT scans for this purpose is associated with concerns regarding radiation exposure. This report introduces a method for monitoring three-dimensional root position following tooth movement during treatment that does not require repeated CBCT scans. This method uses an individual virtual tooth model composed of intraoral-scanned crowns and CBCT-scanned roots. When an evaluation of root positions is needed during treatment, only additional intraoral scan is needed and is integrated into the tooth model; this allows root positions to be estimated without the need for another CBCT scan. The use of a virtual tooth model can potentially allow clinicians to accurately monitor tooth position in routine clinical practice, without the hazards of increased radiation exposure.
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Maret D, Vergnes JN, Peters OA, Peters C, Nasr K, Monsarrat P. Recent Advances in Cone-beam CT in Oral Medicine. Curr Med Imaging 2021; 16:553-564. [PMID: 32484089 DOI: 10.2174/1573405615666190114152003] [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: 09/24/2018] [Revised: 12/09/2018] [Accepted: 12/19/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND The cone-beam computed tomography (CBCT) technology has continuously evolved since its appearance in oral medicine in the early 2000s. OBJECTIVES To present recent advances in CBCT in oral medicine: i) selection of recent and consensual evidence-based sources, ii) structured summary of the information based on an iterative framework and iii) compliance with ethical, public health and patient-centered concerns. MAIN FINDINGS We will focus on technological advances, such as sensors and reconstruction algorithms used to improve the constant quality of the image and dosimetry. CBCT examination is now performed in almost all disciplines of oral medicine: currently, the main clinical disciplines that use CBCT acquisitions are endodontics and oral surgery, with clearly defined indications. Periodontology and ear, nose and throat medicine are more recent fields of application. For a given application and indication, the smallest possible field of view must be used. One of the major challenges in contemporary healthcare is ensuring that technological developments do not take precedence over admitted standards of care. The entire volume should be reviewed in full, with a systematic approach. All findings are noted in the patient's record and explained to the patient, including incidental findings. This presupposes the person reviewing the images is sufficiently trained to interpret such images, inform the patient and organize the clinical pathway, with referrals to other medical or oral medicine specialties as needed. CONCLUSION A close collaboration between dentists, medical physicists, radiologists, radiographers and engineers is critical for all aspects of CBCT technology.
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Affiliation(s)
- Delphine Maret
- Oral Rehabilitation Department, Dental Faculty, Paul Sabatier University, Toulouse University Hospital (CHU de Toulouse), Toulouse, France.,AMIS Laboratory - Laboratoire Anthropologie Moléculaire et Imagerie de Synthèse, Université de Toulouse, UMR 5288 CNRS, UPS, Toulouse, France
| | - Jean-Noel Vergnes
- Epidemiology and Public Health Department, Dental Faculty, Paul Sabatier University, Toulouse University Hospital (CHU de Toulouse), Toulouse, France.,Division of Oral Health and Society, Faculty of Dentistry, McGill University, Montreal, Quebec, Canada
| | - Ove A Peters
- Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California, United States.,School of Dentistry, University of Queensland, Brisbane, Queensland, Australia
| | - Christine Peters
- Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, California, United States
| | - Karim Nasr
- Oral Rehabilitation Department, Dental Faculty, Paul Sabatier University, Toulouse University Hospital (CHU de Toulouse), Toulouse, France
| | - Paul Monsarrat
- Oral Rehabilitation Department, Dental Faculty, Paul Sabatier University, Toulouse University Hospital (CHU de Toulouse), Toulouse, France.,STROMALab, Université de Toulouse, CNRS ERL 5311, EFS, ENVT, Inserm U1031, UPS, Toulouse, France
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Cong A, Massaro C, Ruellas ACDO, Barkley M, Yatabe M, Bianchi J, Ioshida M, Alvarez MA, Aristizabal JF, Rey D, Cevidanes L. Dental long axes using digital dental models compared to cone-beam computed tomography. Orthod Craniofac Res 2021; 25:64-72. [PMID: 33966340 DOI: 10.1111/ocr.12489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Standard methods of evaluating tooth long axes are not comparable (digital dental models [DDMs], panoramic and cephalometric radiographs) or expose patients to more radiation (cone-beam computed tomography [CBCT]). This study aimed to compare angular changes in tooth long axes using DDMs vs using CBCTs. SETTINGS AND SAMPLE POPULATION Secondary data analysis of DDMs and CBCTs, taken before and after orthodontic treatment with piezocision of 24 patients. METHODS Angular changes in tooth long axes were evaluated using landmarks on first molars (centre of the occlusal surface and centre of the furcation), canines and incisors (cusp tip and centre of the root at the cementoenamel junction). Wilcoxon test, intraclass correlation coefficient (ICC) and Bland-Altman plots were used to test intra- and inter-rater agreement and compare DDM and CBCT measurements. RESULTS The mesiodistal angulation and buccolingual inclination DDM measurements were reproducible. Overall mean differences between DDM and CBCT measurements of mesiodistal angulation, 1.9°±1.5°, and buccolingual inclination, 2.2 ± 2.2°, were not significant for all teeth. ICC between DDM and CBCT measurements ranged from good (0.85 molars) to excellent (0.94 canines; 0.96 incisors). The percentages of measurements outside the range of ±5 were 17.4% for molars, 13.8% for canines and 4.5% for incisors. CONCLUSIONS DDM assessment of changes in tooth long axes has good reproducibility and yields comparable measurements to those obtained from CBCT within a 5° range. These findings lay the groundwork for machine learning approaches that synthesize crown and root canal information towards planning tooth movement without the need for ionizing radiation scans.
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Affiliation(s)
- Amalia Cong
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Camila Massaro
- Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil
| | - Antonio Carlos de Oliveira Ruellas
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.,Department of Orthodontics, School of Dentistry, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Mary Barkley
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Marilia Yatabe
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Jonas Bianchi
- Department of Orthodontics, University of the Pacific, Arthur A. Dugoni School of Dentistry, San Francisco, CA, USA
| | - Marcos Ioshida
- Department of Cariology, Restorative Sciences & Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | | | | | - Diego Rey
- Department of Orthodontics, CES University, Medellin, Colombia
| | - Lucia Cevidanes
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
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Jiang T, Wang JK, Jiang YY, Hu Z, Tang GH. How well do integrated 3D models predict alveolar defects after treatment with clear aligners? Angle Orthod 2021; 91:313-319. [PMID: 33492354 DOI: 10.2319/042220-342.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 11/01/2020] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVES To evaluate the accuracy of integrated models (IMs) constructed by pretreatment cone-beam computed tomography (pre-CBCT) in diagnosing alveolar defects after treatment with clear aligners. MATERIALS AND METHODS Pre-CBCT and posttreatment cone-beam computed tomography (CBCT) scans from 69 patients who completed nonextraction treatment with clear aligners were collected. The IMs comprised anterior teeth in predicted positions and alveolar bone from pre-CBCT scans. The accuracy of the IMs for identifying dehiscences or fenestrations was evaluated by comparing the means of the defect volumes, absolute mean differences, and Pearson correlation coefficients with those measured from post-CBCT scans. Defect prediction accuracy was assessed by sensitivity, specificity, positive predictive values, and negative predictive values. Factors possibly affecting changes in mandibular alveolar defects were analyzed using a mixed linear model. RESULTS The IM measurements showed mean deviations of 2.82 ± 9.99 mm3 for fenestrations and 3.67 ± 9.93 mm3 for dehiscences. The absolute mean differences were 4.50 ± 9.35 mm3 for fenestrations and 5.17 ± 9.24 mm3 for dehiscences. The specificities of the IMs were higher than 0.8, whereas the sensitivities were both lower (fenestration = 0.41; dehiscence = 0.53). The positive predictive values were unacceptable (fenestration = 0.52; dehiscence = 0.62), and the overall reliability was low (<0.80). Molar distalization and proclination were positively correlated with significant increases in alveolar defects at the mandibular incisors after treatment. CONCLUSIONS Alveolar defects after clear aligner treatment cannot be simulated accurately by IMs constructed from pre-CBCT. Caution should be taken in the treatment of crowding with proclination and molar distalization for the safety of alveolar bone at the mandibular incisors.
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21
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Weir T. The application of 3D metrology software in the quantitative and qualitative assessment of aligner treatment outcomes. AUSTRALASIAN ORTHODONTIC JOURNAL 2021. [DOI: 10.21307/aoj-2021-011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
Abstract
Abstract
3D metrology software (Geomagic® Control X™) can be used in orthodontic treatment to significantly improve the analysis of achieved tooth movements compared with those predicted by treatment planning software, such as ClinCheck® software (Align Technology®). The applications of this technology enable clinicians to present more accurate and detailed case presentations and analyse their treatment outcomes. Additionally, information presented may further aid clinicians in interpreting and understanding metrology-derived information, in the form of digital heat maps, when incorporated into case presentations and scientific articles.
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22
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Mao H, Yang A, Pan Y, Li H, Lei L. Displacement in root apex and changes in incisor inclination affect alveolar bone remodeling in adult bimaxillary protrusion patients: a retrospective study. Head Face Med 2020; 16:29. [PMID: 33213460 PMCID: PMC7678166 DOI: 10.1186/s13005-020-00242-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 11/09/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Periodontal health is of great concern for periodontists and orthodontists in the inter-disciplinary management of patients with bimaxillary protrusion. The aim of present study is to investigate changes in the alveolar bone in the maxillary incisor region and to explore its relationship with displacement of root apex as well as changes in the inclination of maxillary incisors during incisor retraction. METHODS Samples in this retrospective study consisted of 38 patients with bimaxillary protrusion. Cone-beam computed tomography (CBCT) images was taken before(T0) and after (T1) treatment. Alveolar bone thickness (ABT), height (ABH) and area (ABA) were utilized to evaluate changes in the alveolar bone, while incisor inclination and apex displacement were used to assess changes in the position of maxillary central and lateral incisors. Correlations between alveolar bone remodeling and apex displacement as well as changes in the inclination were investigated. RESULTS The labial ABT of central and lateral incisors at the mid-root third was increased. In contrast, the palatal ABT at crestal, mid-root and apical third level were consistently decreased. ABH was not altered on the labial side, while significantly decreased on the palatal side. ABA was not significantly increased on the labial side, but significantly decreased on the palatal side, leading to a significantly reduced total ABA. Orthodontic treatment significantly reduced inclination of upper incisors. Changes in the amount (T1-T0) of ABA was remarkably correlated with apex displacement and changes of inclination (T1-T0); in addition, using the multivariate linear regression analysis, changes of ABA on the palatal side (T1-T0) can be described by following equation: Changes of palatal ABA (T1-T0) = - 3.258- 0.139× changes of inclination (T1-T0) + 2.533 × apex displacement (T1-T0). CONCLUSIONS Retraction of incisors in bimaxillary protrusion patients may compromise periodontal bone support on the palatal side. An equation that incorporated the displacement of root apex and change in the incisor inclination may enable periodontist-orthodontist interdisciplinary coordination in assessing treatment risks and developing an individualized treatment plan for adult patients with bimaxillary protrusion. Moreover, the equation in predicating area of alveolar bone may reduce the risks of placing the teeth out of the bone boundary during 3D digital setups.
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Affiliation(s)
- Huimin Mao
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Andi Yang
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Yue Pan
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Houxuan Li
- Department of Periodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
| | - Lang Lei
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
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Lim SW, Park H, Lim SY, Choo HH, Baek SH, Hwang HS, Cho JH. Can we estimate root axis using a 3-dimensional tooth model via lingual-surface intraoral scanning? Am J Orthod Dentofacial Orthop 2020; 158:e99-e109. [PMID: 33131571 DOI: 10.1016/j.ajodo.2020.07.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 07/01/2020] [Accepted: 07/01/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION This research aimed to compare the estimation error of the root axis using 3-dimensional (3D) tooth models at the midtreatment stage between the whole-surface scan (WSS) and lingual-surface scan (LSS) methods. METHODS The sample consisted of 208 teeth (26 each of central incisors, canines, second premolars, and first molars in the maxillary and mandibular dentition) from 13 patients whose pre- and midtreatment intraoral scan and cone-beam computed tomography (CBCT) were available. The 3D tooth models were constructed by merging the intraoral-scan crowns and the CBCT-scan roots obtained at the pretreatment stage. To estimate the root axis at the midtreatment stage, we superimposed the individual 3D tooth models onto the midtreatment intraoral scan obtained by the WSS and LSS methods. The midtreatment CBCT scan was used as the gold standard to determine the real root axis. The estimated root axis in terms of mesiodistal angulation and buccolingual inclination was measured in the WSS and LSS methods, and statistical analysis was performed. RESULTS The estimation errors of the mesiodistal angulation and buccolingual inclination were <2.0° in both methods. The LSS method demonstrated a statistically larger but clinically insignificant estimation error than the WSS method in the mandibular canine (mesiodistal angulation, 1.95° vs 1.62°) and the total tested teeth (mesiodistal angulation, 1.40° vs 1.29°; buccolingual inclination, 1.51° vs 1.41°). CONCLUSIONS Because the estimation errors of the root axis angle using the 3D tooth model by the WSS and LSS methods were within the clinically acceptable range, the root axis can be estimated by both methods.
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Affiliation(s)
- Seung-Weon Lim
- Department of Orthodontics, Chonnam National University Dental Hospital, Chonnam National University, Gwangju, South Korea
| | - Hunkyung Park
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | | | | | - Seung-Hak Baek
- Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Hyeon-Shik Hwang
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jin-Hyoung Cho
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, South Korea.
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Lim SW, Moon RJ, Kim MS, Oh MH, Lee KM, Hwang HS, Kim TW, Baek SH, Cho JH. Construction reproducibility of a composite tooth model composed of an intraoral-scanned crown and a cone-beam computed tomography-scanned root. Korean J Orthod 2020; 50:229-237. [PMID: 32632042 PMCID: PMC7369385 DOI: 10.4041/kjod.2020.50.4.229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/30/2020] [Accepted: 03/03/2020] [Indexed: 11/10/2022] Open
Abstract
Objective To evaluate the construction reproducibility of a composite tooth model (CTM) composed of an intraoral-scanned crown and a cone-beam computed tomography (CBCT)-scanned root. Methods The study assessed 240 teeth (30 central incisors, 30 canines, 30 second premolars, and 30 first molars in the maxillary and mandibular arches) from 15 young adult patients whose pre-treatment intraoral scan and CBCT were available. Examiner-Reference (3 years' experience in CTM construction) and Examiners-A and Examiner-B (no experience) constructed the individual CTMs independently by performing the following steps: image acquisition and processing into a three-dimensional model, integration of intraoral-scanned crowns and CBCT-scanned teeth, and replacement of the CBCT-scanned crown with the intraoral-scanned crown. The tooth axis angle in terms of mesiodistal angulation and buccolingual inclination of the CTMs constructed by the three examiners were measured. To assess the construction reproducibility of CTMs, intraclass correlation coefficient (ICC) assessments were performed. Results The ICC values of mesiodistal angulation and buccolingual inclination among the 3 examiners showed excellent agreement (0.950-0.992 and 0.965-0.993; 0.976-0.994 and 0.973-0.995 in the maxillary and mandibular arches, respectively). Conclusions The CTM showed excellent construction reproducibility in mesiodistal angulation and buccolingual inclination regardless of the construction skill and experience levels of the examiners.
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Affiliation(s)
- Seung-Weon Lim
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Ryu-Jin Moon
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Min-Seok Kim
- Department of Oral Anatomy, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Min-Hee Oh
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Kyung-Min Lee
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Hyeon-Shik Hwang
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Tae-Woo Kim
- Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, Korea
| | - Seung-Hak Baek
- Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, Korea
| | - Jin-Hyoung Cho
- Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
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Terada K, Kameda T, Kageyama I, Sakamoto M. Estimation of three-dimensional long axes of the maxillary and mandibular first molars with regression analysis. Anat Sci Int 2020; 95:126-133. [PMID: 31654329 PMCID: PMC6942590 DOI: 10.1007/s12565-019-00506-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 10/10/2019] [Indexed: 11/17/2022]
Abstract
The purpose of this study was to determine the long axes of molars with multiple roots through ordinary least squares regression (LSR) and to compare them with the axes defined by principal component analysis (PCA). Three-dimensional radiological images of 20 dry skulls were obtained by cone-beam computed tomography (CBCT). Data from maxillary and mandibular first molars were extracted from the CBCT DICOM data with a three-dimensional image visualization system. The obtained data were reconstructed, converted to STL files, and three-dimensional coordinate values were extracted. The long axes were estimated by an algorithm to synchronize the LSR line with the horizontal axis which was translated to the vertical axis. The axes of the molars defined by LSR were compared with the axes of the molars defined by PCA. The coordinate point number of each molar was 5400-5800. The algorithm for determining the tooth axes in this study consisted of four stages containing three steps each. The distance between the two axes calculated by the two methods (LSR and PCA) on the horizontal plane through the origin was less than 10-12 mm and the deviations between them were less than 0.003°. The long axes of the molars estimated by LSR agree almost exactly with the axes estimated by PCA, and the accuracy is sufficient for clinical usage; however, the distance between them would shorten with a more severe convergence condition of the α value at each stage of this LSR system.
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Affiliation(s)
- Kazuto Terada
- Orthodontic Dentistry, The Nippon Dental University Niigata Hospital, 1-8 Hamaura-cho, Chuo-ku, Niigata, 951-8580, Japan.
| | - Takashi Kameda
- Department of Orthodontics, The Nippon Dental University at Niigata, 1-8 Hamaura-cho, Chuo-ku, Niigata, 951-8580, Japan
| | - Ikuo Kageyama
- Department of Anatomy, The Nippon Dental University at Niigata, 1-8 Hamaura-cho, Chuo-ku, Niigata, 951-8580, Japan
| | - Makoto Sakamoto
- Department of Health Sciences, Niigata University School of Medicine, 2-746 Asahimachi-dori, Chuo-ku, Niigata, 951-8518, Japan
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Lee RJ, Ko J, Park J, Pi S, Devgon D, Nelson G, Hatcher D, Oberoi S. Accuracy and reliability of the expected root position setup on clinical decision making of root position at midtreatment. Am J Orthod Dentofacial Orthop 2019; 156:566-573. [PMID: 31582128 DOI: 10.1016/j.ajodo.2019.03.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 03/01/2019] [Accepted: 03/01/2019] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Accurate root position is imperative for successful orthodontic treatment that is stable and functional. Current methods to monitor root position are either inaccurate or use relatively high levels of radiation. A method to generate an expected root position (ERP) setup has been reported to have the potential to accurately evaluate root position with minimal radiation. The purpose of this study was to determine the accuracy and reliability of the clinical decisions made on root position using the ERP setup. METHODS This retrospective study included 10 subjects who had pretreatment and midtreatment cone-beam computed tomography (CBCT) scans and study models. An ERP setup was generated for all patients at midtreatment. Four examiners assessed both the CBCT scan and ERP setup and made clinical decisions regarding the root position with each method. Cohen's kappa was determined to assess intraoperator and intermethod reliability. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to determine the accuracy of the ERP setup. RESULTS The kappa values for intraoperator reliability for both the CBCT scan and ERP setup fell within the 0.61-0.80 range. The kappa values for intermethod reliability between the CBCT scan and ERP setup fell within the 0.61-0.80 range for all tooth groups. The sensitivity of the ERP setup ranged from 0.72 to 0.90, specificity ranged from 0.89 to 0.97, positive predictive value ranged from 0.57 to 0.85, and negative predictive value ranged from 0.93 to 0.99. CONCLUSIONS This study demonstrated that the ERP setup, when compared with the gold standard CBCT scan, was accurate and reliable in making clinical decisions regarding root position at midtreatment.
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Affiliation(s)
- Robert J Lee
- Division of Orthodontics, University of California, San Francisco, San Francisco, Calif.
| | - Jaemin Ko
- Division of Orthodontics, University of California, San Francisco, San Francisco, Calif
| | - Justyn Park
- School of Dentistry, University of California, San Francisco, San Francisco, Calif
| | - Sarah Pi
- School of Dentistry, University of California, San Francisco, San Francisco, Calif
| | - Denise Devgon
- Department of Preventive & Restorative Dentistry, University of California, San Francisco, San Francisco, Calif
| | - Gerald Nelson
- Division of Orthodontics, University of California, San Francisco, San Francisco, Calif
| | - David Hatcher
- Department of Orofacial Sciences, University of California, San Francisco, San Francisco, Calif
| | - Snehlata Oberoi
- Department of Orofacial Sciences, University of California, San Francisco, San Francisco, Calif
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Siécola G, Henriques JFC, Freitas KMS, Janson G. Dentoalveolar changes in adults promoted by the use of auxiliary expansion arch: A cbct study. J Clin Exp Dent 2019; 11:e898-e905. [PMID: 31636859 PMCID: PMC6797465 DOI: 10.4317/jced.56169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 09/09/2019] [Indexed: 11/12/2022] Open
Abstract
Background The objective of this study was to evaluate the dentoalveolar effects and the changes of buccal cortical bone in the posterior area after expansion obtained with TMA auxiliary expansion arch in adult patients. Material and Methods A retrospective analysis of CT scans of 13 patients (6 male, 7 female) treated at a private clinic, taken immediately before and after the use of an auxiliary expansion archwire, was performed. Mean age at installation of TMA auxiliary expansion arch was 29.23 years (s.d.=9.13) and the mean age when the auxiliary arch was removed was 29.52 years (s.d.=9.16). Mean time of the use of the TMA auxiliary expansion arch was 0.29 years (s.d.=0.09). The patients used fixed appliances and after leveling and alignment, a TMA auxiliary expansion arch was installed, combined with the primary 0.017x0.025-inch thermoactivated Ni-Ti archwire. CBCT scans were taken at T1 and T2. Linear and angular measurements regarding the positioning of maxillary molar, premolars and canines were performed. Intragroup comparison of the variables at T1 and T2 was performed with dependent t tests. Results There was statistically significant transverse increase and buccal inclination of all teeth. The cortical bone showed adaptability and displacement in the same direction of tooth movement, but in smaller amounts. Conclusions The auxiliary expansion arch proved to be effective to correct dentoalveolar constriction in adult patients, by increasing the buccal dental inclination with larger displacements than the bone crest adaptation and with significant transverse gains. Key words:Cone-Beam Computed Tomography, Maxillary Expansion, Adult treatment.
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Affiliation(s)
- Gustavo Siécola
- D.D.S., M.Sc., Ph.D. Orthodontic graduate student. Department of Orthodontics, Bauru Dental School, University of São Paulo. Bauru, SP, Brazil
| | | | | | - Guilherme Janson
- D.D.S., M.Sc., Ph.D., M.R.C.D.C. (Member of the Royal College of Dentists of Canada). Professor and Head. Department of Orthodontics. Bauru Dental School, University of São Paulo, Brazil
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Likitmongkolsakul U, Aksornmuang J, Smithmaitrie P, Samruajbenjakun B. Three-Dimensional Simulation of Root Position Through a Combined Technique Using Cone-Beam Computed Tomography and a Digital Model. JOURNAL OF INDIAN ORTHODONTIC SOCIETY 2019. [DOI: 10.1177/0301574219840891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Objective: The aim of this study was to develop a method to simulate root position in the patient and to evaluate the accuracy of all procedures.Materials and Methods: In Part I, the accuracy of a tooth model generated using cone-beam computed tomography (CBCT) was evaluated. Mesiodistal width was measured and compared between digital models and actual teeth. In Part II, the accuracy of simulated root positions generated in the scanned model was evaluated. Simulated root models were superimposed on the scanned dental model using the best fit method. The distances between the reference wire and the tooth were compared. In Part III, the simulated method was used with real orthodontic patients. The distances between the mini-implant and the tooth were compared.Results: Part I: The range of the differences was −0.106 to 0.152 mm. Part II: The range of the differences between the distance of the constructed tooth model and the simulated model was −0.065 to 0.256 mm. Part III: The range of the differences between the distance of the constructed tooth model and the simulated model was −0.089 to 0.135 mm. This technique provided high accuracy, with an average error of only 0.054 mm.Conclusion: High accuracy of the constructed model was achieved. Simulation of root position in a patient can be accomplished by combining data from CBCT and the digital model. This technique might be used effectively in orthodontic treatment.
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Affiliation(s)
- Udomsak Likitmongkolsakul
- Departments of Preventive Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Juthatip Aksornmuang
- Departments of Conservative Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Pruittikorn Smithmaitrie
- Department of Mechanical Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Bancha Samruajbenjakun
- Departments of Preventive Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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González Guzmán JF, Teramoto Ohara A. Evaluation of three-dimensional printed virtual setups. Am J Orthod Dentofacial Orthop 2019; 155:288-295. [DOI: 10.1016/j.ajodo.2018.08.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 08/01/2018] [Accepted: 08/01/2018] [Indexed: 11/26/2022]
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Staderini E, Guglielmi F, Cornelis MA, Cattaneo PM. Three-dimensional prediction of roots position through cone-beam computed tomography scans-digital model superimposition: A novel method. Orthod Craniofac Res 2018; 22:16-23. [PMID: 30449070 DOI: 10.1111/ocr.12252] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/12/2018] [Accepted: 11/13/2018] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To introduce a new, fast, reliable, and free from software-related bias method to predict three-dimensionally the root position and angulation during and after orthodontic treatment. The final goal is to keep to a minimum the use of ionizing radiation by eliminating the necessity of multiple radiation exposure for checking root alignment. SETTING AND SAMPLE POPULATION Pre- and post-treatment digital models and cone-beam computed tomographic (CBCT) scans from a patient were retrieved. MATERIAL AND METHODS The post-treatment digital model (post-model) was set as the reference; pre- and post-treatment CBCT scans were pre-aligned to the post-model with a point set registration; iterative closest point algorithm was then employed for final adjustments. The accuracy of the proposed method was assessed by comparing the average distance between the expected root position setup with the true position of the roots, as from the post-treatment CBCT. RESULTS After crown superimposition, 3D colour maps showed that the accuracy of the root prediction was below 0.1 mm. CONCLUSION The proposed digital workflow allows to predict in an accurate and truly three-dimensional way the final position of roots, when an initial CBCT is available, without the need of an extra X-ray examination for the patient at the end of treatment. The limitation of the exposure to mid- and post-treatment X-rays is in accordance with the ALARA (As Low As Reasonably Achievable) principle and it is even more relevant in growing patients.
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Affiliation(s)
- Edoardo Staderini
- Institute of Dentistry, Head: Prof. M. Cordaro. Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italy.,Section of Orthodontics, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark
| | - Federica Guglielmi
- Institute of Dentistry, Head: Prof. M. Cordaro. Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Marie A Cornelis
- Section of Orthodontics, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark
| | - Paolo M Cattaneo
- Section of Orthodontics, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark
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Lee RJ, Pi S, Park J, Devgon D, Nelson G, Hatcher D, Oberoi S. Accuracy and reliability of the expected root position setup methodology to evaluate root position during orthodontic treatment. Am J Orthod Dentofacial Orthop 2018; 154:583-595. [PMID: 30268268 DOI: 10.1016/j.ajodo.2018.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/01/2018] [Accepted: 04/01/2018] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Current methods to evaluate root position either are inaccurate (panoramic radiograph) or expose patients to relatively large amounts of radiation (cone-beam computed tomography [CBCT]). A method to evaluate root position by generating an expected root position (ERP) setup was recently reported but has not been validated. The purpose of this study was to quantitatively assess the accuracy and reliability of the ERP setup with adequate statistical power. METHODS This retrospective study included 15 subjects who had completed phase 2 orthodontic treatment. An ERP setup was generated for all patients after treatment. The ERP setup was compared with the posttreatment CBCT scan, which served as the control. The mesiodistal angulation and buccolingual inclination of all teeth in both the ERP setup and the posttreatment CBCT scan were measured and compared. Bland-Altman analysis was used to assess interoperator reliability, intraoperator reliability, and agreement between the ERP setup and the posttreatment CBCT scan. RESULTS Bland-Altman plots showed high interoperator and intraoperator reliabilities. These plots also showed strong agreement between the ERP setup and the posttreatment CBCT scan; 11.8% of teeth measured for mesiodistal angulation and 9.6% of teeth measured for buccolingual inclination were outside the ±2.5° range of clinical acceptability. CONCLUSIONS We validated that the method to generate an ERP setup to evaluate root position for posttreatment orthodontic assessment is accurate and reliable.
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Affiliation(s)
- Robert J Lee
- Division of Orthodontics, University of California at San Francisco, San Francisco, Calif.
| | - Sarah Pi
- School of Dentistry, University of California at San Francisco, San Francisco, Calif
| | - Justyn Park
- School of Dentistry, University of California at San Francisco, San Francisco, Calif
| | - Denise Devgon
- Division of Orthodontics, University of California at San Francisco, San Francisco, Calif
| | - Gerald Nelson
- Division of Orthodontics, University of California at San Francisco, San Francisco, Calif
| | - David Hatcher
- Department of Orofacial Sciences, University of California at San Francisco, San Francisco, Calif
| | - Snehlata Oberoi
- Department of Orofacial Sciences, University of California at San Francisco, San Francisco, Calif
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Likitmongkolsakul U, Smithmaitrie P, Samruajbenjakun B, Aksornmuang J. Development and Validation of 3D Finite Element Models for Prediction of Orthodontic Tooth Movement. Int J Dent 2018; 2018:4927503. [PMID: 30245719 PMCID: PMC6136563 DOI: 10.1155/2018/4927503] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/10/2018] [Accepted: 07/29/2018] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES The aim of this study was to develop and validate three-dimensional (3D) finite element modeling for prediction of orthodontic tooth movement. MATERIALS AND METHODS Two orthodontic patients were enrolled in this study. Computed tomography (CT) was captured 2 times. The first time was at T0 immediately before canine retraction. The second time was at T4 precisely at 4 months after canine retraction. Alginate impressions were taken at 1 month intervals (T0-T4) and scanned using a digital scanner. CT data and scanned models were used to construct 3D models. The two measured parameters were clinical tooth movement and calculated stress at three points on the canine root. The calculated stress was determined by the finite element method (FEM). The clinical tooth movement was measured from the differences in the measurement points on the superimposed model. Data from the first patient were used to analyze the tooth movement pattern and develop a mathematical formula for the second patient. Calculated orthodontic tooth movement of the second patient was compared to the clinical outcome. RESULTS Differences between the calculated tooth movement and clinical tooth movement ranged from 0.003 to 0.085 mm or 0.36 to 8.96%. The calculated tooth movement and clinical tooth movement at all reference points of all time periods appeared at a similar level. Differences between the calculated and clinical tooth movements were less than 0.1 mm. CONCLUSION Three-dimensional FEM simulation of orthodontic tooth movement was achieved by combining data from the CT and digital model. The outcome of the tooth movement obtained from FEM was found to be similar to the actual clinical tooth movement.
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Affiliation(s)
- Udomsak Likitmongkolsakul
- Orthodontic Section, Department of Preventive Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Pruittikorn Smithmaitrie
- Department of Mechanical Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Bancha Samruajbenjakun
- Orthodontic Section, Department of Preventive Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Juthatip Aksornmuang
- Prosthodontic Section, Department of Conservative Dentistry, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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Lee RJ, Pi S, Park J, Nelson G, Hatcher D, Oberoi S. Three-dimensional evaluation of root position at the reset appointment without radiographs: a proof-of-concept study. Prog Orthod 2018; 19:15. [PMID: 29862456 PMCID: PMC5985242 DOI: 10.1186/s40510-018-0214-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/24/2018] [Indexed: 11/21/2022] Open
Abstract
Background Accurate root position is integral for successful orthodontic treatment. Current methods of monitoring root position are either inaccurate, exhibit poor resolution, or use relatively large amount of radiation relative to the benefits for the patient. The purpose of this study was to present an approach that can monitor root position during orthodontic treatment with minimal radiation. Methods Cone-beam computed tomography (CBCT) scans were taken for a patient at pre-treatment and at a dedicated reset appointment. An extra-oral laser scan of a poured up cast was taken at the reset appointment. An expected root position (ERP) setup, an approximation of the root position at the reset appointment, was generated using the pre-treatment CBCT scan and reset appointment cast. The ERP setup was compared to the CBCT scan taken at the reset appointment which served as the control. Color displacement maps were generated to measure any differences between the expected and true root positions. Results Color map displacement analysis after indirect superimposition found displacement differences of 0.021 mm ± 0.396 mm for the maxillary roots and 0.079 mm ± 0.499 mm for the mandibular roots. Conclusions This approach was demonstrated in a patient at the reset appointment to have the potential to accurately monitor root positions during treatment in three dimensions without the need for additional radiographs.
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Affiliation(s)
- Robert J Lee
- Division of Orthodontics, University of California San Francisco, 707 Parnassus Ave. d3000, San Francisco, CA, 94143, USA.
| | - Sarah Pi
- School of Dentistry, University of California San Francisco, San Francisco, CA, USA
| | - Justyn Park
- School of Dentistry, University of California San Francisco, San Francisco, CA, USA
| | - Gerald Nelson
- Division of Orthodontics, University of California San Francisco, 707 Parnassus Ave. d3000, San Francisco, CA, 94143, USA
| | - David Hatcher
- Department of Orofacial Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Snehlata Oberoi
- Department of Orofacial Sciences, University of California San Francisco, San Francisco, CA, USA
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Chardey EK, Fastuca R, Beretta M, Di Blasio A, Vercellini N, Caprioglio A, Zecca PA, Macchi A. Digital Dynamic 3D Monitoring of Lower Incisors Intrusion in Lingual Orthodontics. Open Dent J 2018; 12:104-117. [PMID: 29492176 PMCID: PMC5815052 DOI: 10.2174/1874210601812010104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 12/20/2017] [Accepted: 01/05/2018] [Indexed: 11/22/2022] Open
Abstract
Objective The aim of the present study is to propose a 3-dimensional evaluation of lower intrusion obtained with lingual orthodontics considering not only the crowns but also dental roots. Methods 9 adult patients underwent fixed lingual orthodontic treatment with i-TTя lingual brackets system for the correction of crowding in the lower arch associated with a deep overbite. Initial records, consisting of photos, CBCTs and intraoral scans were collected. Threshold segmentation of the CBCT was performed to generate a three-dimensional virtual model of each the teeth of the lower arch, superimposed with the crown of the same teeth obtained by intraoral scan models to generate a complete set of digital composite lower arch The same procedure was performed to monitor one key step of the i-TTЯ technique consisting in lower incisors intrusion (T2). T1-T2 three-dimensional superimposition and color displacement maps were generated to measure and evaluate the movements obtained at the lower arch. Results The root displacement of the incisors during their intrusion in the early stage was totally "bone-safe" in the 88.9% (8 of 9) of the cases observed. No significant extrusion of the premolars used as anchorage unit was measured. Conclusion This method has proved to be an accurate and reliable approach to dynamically visualize the 3-dimensional positions of the teeth, including their roots, with no additional radiation for in-progress treatment monitoring. The 3-dimensional evaluation showed that the employed lingual appliance allowed to obtain significant lower incisors intrusion with negligible undesired extrusion of premolars employed as anchorage teeth.
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Affiliation(s)
- Elia Kodjo Chardey
- Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
| | - Rosamaria Fastuca
- Department of Biomedical Sciences, Dentistry and Morphological and Functional Imaging, University of Messina, Messina, Italy
| | - Matteo Beretta
- Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
| | - Alberto Di Blasio
- Department of Biotechnological, Biomedical and Translational Sciences, Section of Orthodontics, University of Parma, Parma, Italy
| | - Nicolò Vercellini
- Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
| | - Alberto Caprioglio
- Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Piero Antonio Zecca
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Aldo Macchi
- Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
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Dai N, Li D, Yang X, Cheng C, Sun Y. Research and primary evaluation of an automatic fusion method for multisource tooth crown data. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:e2878. [PMID: 28257608 DOI: 10.1002/cnm.2878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/26/2017] [Accepted: 02/27/2017] [Indexed: 06/06/2023]
Abstract
With the development of 3-dimensional (3D) scanning technologies in dentistry, high accuracy optical scanning data from the crown and cone beam computed tomography data from the root can be acquired easily. In many dental fields, especially in digital orthodontics, it is useful to fuse the data from the crown and the root. However, the manual fusion method is complex and difficult. A novel automatic fusion method for 2-source data from the crown and the root was researched, and its accuracy was evaluated in this study. An occlusal splint with several alumina ceramic spheres was fabricated using heat-curing resin. A multipoint (center of each sphere) alignment method was performed to achieve rapid registration of the crown data from optical scanning and the root data from cone beam computed tomography. The segmentation algorithm based on heuristic search was adopted to perform extraction and segmentation of the crown from whole optical scanning data. The level set algorithm and the marching cubes (MC) algorithm were used to reconstruct digital imaging and communications in medicine data into a 3D model. A novel multisource data fusion algorithm, which is based on iterative Laplacian deformation (ILD), was researched and applied to achieve automatic fusion. Finally, the 3D errors of the method were evaluated. The 3 groups of typical tooth data were automatically fused within 2 seconds. The mean standard deviation was less than 0.02 mm. The novel method can aid the construction of a high-quality 3D model of complete teeth to enable orthodontists to safely, reliably, and visually plan tooth alignment programs.
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Affiliation(s)
- Ning Dai
- College of Mechanical & Electrical Engineering, Nanjing University of Aeronautics & Astronautics, 210016, Nanjing, People's Republic of China
| | - Dawei Li
- College of Mechanical & Electrical Engineering, Nanjing University of Aeronautics & Astronautics, 210016, Nanjing, People's Republic of China
| | - Xu Yang
- Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, 100081, Beijing, People's Republic of China
| | - Cheng Cheng
- College of Mechanical & Electrical Engineering, Nanjing University of Aeronautics & Astronautics, 210016, Nanjing, People's Republic of China
| | - Yuchun Sun
- Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, 100081, Beijing, People's Republic of China
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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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Bouton A, Simon Y, Goussard F, Teresi L, Sansalone V. Nouveau protocole d’étude par élément finis : simulation clinique du mouvement dentaire orthodontique. Int Orthod 2017; 15:165-179. [DOI: 10.1016/j.ortho.2017.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Bouton A, Simon Y, Goussard F, Teresi L, Sansalone V. New finite element study protocol: Clinical simulation of orthodontic tooth movement. Int Orthod 2017; 15:165-179. [PMID: 28416159 DOI: 10.1016/j.ortho.2017.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The aim of this work was to model tooth movement in a more clinically-exact fashion, thanks to the use of new IT tools and imaging systems (cone-beam). Image segmentation and 3D reconstruction now enable us to model the anatomy realistically, while finite element (FE) analysis makes it possible to evaluate stresses and their distribution on the level of the tooth, the periodontal ligament (PDL) and the alveolar bone when a force is applied. The principle is to monitor tooth movement by obtaining optical impressions at each stage of treatment. The model corresponds to a genuine clinical situation. FE analysis is correlated with the clinically-observed displacement. The protocol remains long and complex. It nevertheless makes it possible to obtain, throughout the duration of treatment, patient-specific models that can be exploited using finite element methods. It requires further validation in more thorough studies but offers interesting prospects: precise study of induced tooth movement, distribution of stresses in the PDL, and development of a customized previsualization tool.
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Affiliation(s)
| | - Yohann Simon
- Département d'orthopédie-dento-faciale, service d'odontologie, hôpital Bretonneau, 2, rue Carpeaux, 75018 Paris, France
| | - Florent Goussard
- Département histoire de la terre, UMR7207, CR2P, CNRS, "centre de recherche sur la paléobiodiversité et les paléoenvironnements", laboratoire de paléontologie, Muséum National d'Histoire Naturelle, 8, rue Buffon, CP38, 75005 Paris, France
| | - Luciano Teresi
- LaMS, Modelling & Simulation Lab, Department of Mathematics & Physics, Università Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
| | - Vittorio Sansalone
- MSME UMR 8208 CNRS, laboratoire modélisation et simulation multi-échelle, université Paris-Est, 61, avenue du Général-de-Gaulle, 94010 Créteil cedex, France
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Sang YH, Hu HC, Lu SH, Wu YW, Li WR, Tang ZH. Accuracy Assessment of Three-dimensional Surface Reconstructions of In vivo Teeth from Cone-beam Computed Tomography. Chin Med J (Engl) 2017; 129:1464-70. [PMID: 27270544 PMCID: PMC4910372 DOI: 10.4103/0366-6999.183430] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: The accuracy of three-dimensional (3D) reconstructions from cone-beam computed tomography (CBCT) has been particularly important in dentistry, which will affect the effectiveness of diagnosis, treatment plan, and outcome in clinical practice. The aims of this study were to assess the linear, volumetric, and geometric accuracy of 3D reconstructions from CBCT and to investigate the influence of voxel size and CBCT system on the reconstructions results. Methods: Fifty teeth from 18 orthodontic patients were assigned to three groups as NewTom VG 0.15 mm group (NewTom VG; voxel size: 0.15 mm; n = 17), NewTom VG 0.30 mm group (NewTom VG; voxel size: 0.30 mm; n = 16), and VATECH DCTPRO 0.30 mm group (VATECH DCTPRO; voxel size: 0.30 mm; n = 17). The 3D reconstruction models of the teeth were segmented from CBCT data manually using Mimics 18.0 (Materialise Dental, Leuven, Belgium), and the extracted teeth were scanned by 3Shape optical scanner (3Shape A/S, Denmark). Linear and volumetric deviations were separately assessed by comparing the length and volume of the 3D reconstruction model with physical measurement by paired t-test. Geometric deviations were assessed by the root mean square value of the imposed 3D reconstruction and optical models by one-sample t-test. To assess the influence of voxel size and CBCT system on 3D reconstruction, analysis of variance (ANOVA) was used (α = 0.05). Results: The linear, volumetric, and geometric deviations were −0.03 ± 0.48 mm, −5.4 ± 2.8%, and 0.117 ± 0.018 mm for NewTom VG 0.15 mm group; −0.45 ± 0.42 mm, −4.5 ± 3.4%, and 0.116 ± 0.014 mm for NewTom VG 0.30 mm group; and −0.93 ± 0.40 mm, −4.8 ± 5.1%, and 0.194 ± 0.117 mm for VATECH DCTPRO 0.30 mm group, respectively. There were statistically significant differences between groups in terms of linear measurement (P < 0.001), but no significant difference in terms of volumetric measurement (P = 0.774). No statistically significant difference were found on geometric measurement between NewTom VG 0.15 mm and NewTom VG 0.30 mm groups (P = 0.999) while a significant difference was found between VATECH DCTPRO 0.30 mm and NewTom VG 0.30 mm groups (P = 0.006). Conclusions: The 3D reconstruction from CBCT data can achieve a high linear, volumetric, and geometric accuracy. Increasing voxel resolution from 0.30 to 0.15 mm does not result in increased accuracy of 3D tooth reconstruction while different systems can affect the accuracy.
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Affiliation(s)
- Yan-Hui Sang
- Second Dental Center, Peking University School and Hospital of Stomatology, Beijing 100101; Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Hong-Cheng Hu
- Second Dental Center, Peking University School and Hospital of Stomatology, Beijing 100101; National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Song-He Lu
- Second Dental Center, Peking University School and Hospital of Stomatology, Beijing 100101; National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Yu-Wei Wu
- Second Dental Center, Peking University School and Hospital of Stomatology, Beijing 100101; National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Wei-Ran Li
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Zhi-Hui Tang
- Second Dental Center, Peking University School and Hospital of Stomatology, Beijing 100101; National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, China
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Weissheimer A, Menezes LM, Koerich L, Pham J, Cevidanes LHS. Fast three-dimensional superimposition of cone beam computed tomography for orthopaedics and orthognathic surgery evaluation. Int J Oral Maxillofac Surg 2015; 44:1188-96. [PMID: 25935632 DOI: 10.1016/j.ijom.2015.04.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 02/18/2015] [Accepted: 04/06/2015] [Indexed: 11/16/2022]
Abstract
The aim of this study was to validate a method for fast three-dimensional (3D) superimposition of cone beam computed tomography (CBCT) in growing patients and adults (surgical cases). The sample consisted of CBCT scans of 18 patients. For 10 patients, as the gold standard, the spatial position of the pretreatment CBCT was reoriented, saved as a reoriented volume, and then superimposed on the original image. For eight patients, four non-growing and four growing, the pre- and post-treatment scans were superimposed. Fast voxel-based superimposition was performed, with registration at the anterior cranial base. This superimposition process took 10-15s. The fit of the cranial base superimposition was verified by qualitative visualization of the semi-transparent axial, sagittal, and coronal cross-sectional slices of all corresponding anatomical structures. Virtual 3D surface models of the skull were generated via threshold segmentation, and superimposition errors in the reoriented models and the results of treatment for the treated cases were evaluated by 3D surface distances on colour-coded maps. The superimposition error of the spatial reorientation and for growing and non-growing patients was <0.5mm, which is acceptable and clinically insignificant. The voxel-based superimposition method evaluated was reproducible in different clinical conditions, rapid, and applicable for research and clinical practice.
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Affiliation(s)
- A Weissheimer
- Department of Orthodontics, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - L M Menezes
- Department of Orthodontics, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - L Koerich
- International Dental Program, Virginia Commonwealth University, Richmond, VA, USA
| | - J Pham
- Advanced Orthodontic Program, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - L H S Cevidanes
- Department of Orthodontics at the University of Michigan School of Dentistry, Ann Arbor, MI, USA
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