1
|
Koru Akan BE, Hancıoğlu Kircelli B, Paşaoğlu Bozkurt A, Gögen H. Evaluation of the effects of semipontic design on tooth movements during mesialization of mandibular second molar performed with clear aligner treatment by finite element analysis. Am J Orthod Dentofacial Orthop 2024:S0889-5406(24)00277-4. [PMID: 39140924 DOI: 10.1016/j.ajodo.2024.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2024] [Revised: 07/11/2024] [Accepted: 07/01/2024] [Indexed: 08/15/2024]
Abstract
INTRODUCTION Loss of the mandibular first molar is common in orthodontic patients. One treatment option is the mesialization of the second and third molars. This study aimed to investigate the displacement and type of movement in the second molar during mandibular second molar mesialization with clear aligner treatment using finite element analysis in configurations with or without pontic, semipontic, and anatomic pontic for the edentulous space. METHODS Mesialization of the mandibular second molar with clear aligner treatment was simulated using the AlGOR Fempro program (ALGOR, Inc, Pa) with 3 different configurations. RESULTS In the transverse direction, the highest rotation occurred in the anatomic pontic model, whereas the lowest rotation was in the semipontic model. In the sagittal axis, although tooth movement was realized by tipping in all scenarios, the semipontic model showed the closest movement to translation because of a higher rate of crown-root movement. In the vertical axis, although extrusion occurred in all configurations, the semipontic model showed the least extrusion forces, whereas the anatomic pontic model showed the most. CONCLUSIONS Mesiobuccal rotation, mesial tipping, and extrusion were observed in all models. However, the semipontic design had the closest movement to translational. Further randomized, controlled clinical trials are needed to evaluate the effects of different pontic designs on tooth movements.
Collapse
Affiliation(s)
- Burcu Ece Koru Akan
- Department of Orthodontics, Faculty of Dentistry, Istanbul Aydin University, Istanbul, Turkey.
| | | | - Aylin Paşaoğlu Bozkurt
- Department of Orthodontics, Faculty of Dentistry, Istanbul Aydin University, Istanbul, Turkey
| | | |
Collapse
|
2
|
Yuan X, Liu L, Fan Q, Zhou H, Wang Y, Lai W, Long H. Uprighting and protraction of two unilateral mandibular molars using a cantilever arm through a sophisticated biomechanical system with clear aligner: A case report. Int Orthod 2024; 22:100893. [PMID: 38996691 DOI: 10.1016/j.ortho.2024.100893] [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: 06/08/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 07/14/2024]
Abstract
Although clear aligner can be efficient and predictable in some tooth movements, mandibular molar protraction is the least predictable owing to biological and biomechanical limitations. This case report presents a 20-year-old female with poor prognosed left mandibular first molar (#36), deviated dental midline and mild crowding. After extraction of #36, clear aligners and an Albert cantilever were used for treatment. Through carefully designed dual mechanical system, we achieved uprighting and protraction of #37 within 27 months, with crown and root movements of 9.9mm and 12.1mm, respectively. The predictability of the crown and root movement was 107.6% and 84.6%. Coincident dental and facial midline, class I molar and canine relationship and good root parallelism were also achieved. Large-distance mandibular molar protraction can be achieved effectively with a combination of Albert cantilever arm and clear aligner.
Collapse
Affiliation(s)
- Xuechun Yuan
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Lu Liu
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; Department of Maxillofacial Orthognathics, Graduate school, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, 113-8510 Tokyo, Japan
| | - Qi Fan
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Hong Zhou
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yan Wang
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Wenli Lai
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Hu Long
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, Sichuan, China; State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China.
| |
Collapse
|
3
|
He X, Huang Z, Yang Y, Yuan X, Wen S, Li Y, Hu G, Lai W, Long H. A Bibliometric Analysis of Clear Aligner Treatment (CAT) From 2003 to 2023. Cureus 2024; 16:e63348. [PMID: 39077282 PMCID: PMC11283927 DOI: 10.7759/cureus.63348] [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] [Accepted: 06/19/2024] [Indexed: 07/31/2024] Open
Abstract
Clear aligner treatment (CAT) has been evolving over the past two decades. This study aims to conduct a comprehensive and up-to-date bibliometric analysis of publications related to CAT, presenting the research trends, landscapes, and hot spots in this field. All publications were retrieved from the Web of Science Core Collection from 2003 to 2023. In addition to a general analysis of research landscapes, the following items were analyzed, i.e., countries, institutions, authors, journals, publications, and keywords. A total of 1031 relevant publications were included in this study. From 2003 to the present, the number of publications and citations in this field showed an increasing trend. Italy led in terms of publication counts, and Sichuan University in China had the highest publication counts among institutions. In total, 33 scholars had published a minimum of 10 articles, and the collaborations among them were mostly within each country. The American Journal of Orthodontics and Dentofacial Orthopedics published the most relevant publications. "Predictability of tooth movements," "influencing factors for clinical efficacy," "biomechanics," and "patients' perception and periodontal health" stood out as the core research focus on CAT. Our study identified the most influential countries, institutions and authors, and their cooperative relationships, and detected hot research topics on CAT, calling for more high-quality international collaborative research in the future.
Collapse
Affiliation(s)
- Xian He
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Zeyu Huang
- West China School of Stomatology, Sichuan University, Chengdu, CHN
| | - Yi Yang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Xuechun Yuan
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Shangyou Wen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Yuetian Li
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Guannan Hu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Wenli Lai
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| | - Hu Long
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN
| |
Collapse
|
4
|
Gao Y, Sun X, Yan X, Tang Z, Lai W, Long H. Orthodontic Practitioners' Knowledge and Education Demand on Clear Aligner Therapy. Int Dent J 2024; 74:81-87. [PMID: 37500450 PMCID: PMC10829360 DOI: 10.1016/j.identj.2023.07.001] [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: 03/10/2023] [Revised: 06/14/2023] [Accepted: 07/03/2023] [Indexed: 07/29/2023] Open
Abstract
OBJECTIVES Clear aligner therapy (CAT) has been gaining popularity amongst the orthodontic community. No systematic course on CAT has been reported to date. The objectives of this study were to determine practitioners' knowledge and to offer insights for future tailored courses on CAT. METHODS An online questionnaire was distributed. The questionnaire comprised personal background information, predictability of tooth movement through CAT, and CAT knowledge that practitioners demanded to learn. Four senior expert orthodontists' answers to the predictability of tooth movement through CAT were averaged to be a standard reference. Descriptive statistics, 1-way analysis of variance (ANOVA), principal component analysis, Student t test, and multivariate logistics regression analysis were performed with significance set at P < .05. RESULTS In total, 190 practitioners participated in this study. As compared to the standard reference, participants overestimated the predictability of difficult-to-be-achived tooth movements (eg, molar mesialisation; P < .0001). Strategy of managing troubleshooting cases and extraction cases ranked the highest CAT knowledge that participants requested to learn. Practice type, number of completed CAT cases, number of undergoing CAT cases, years of practice, education background, and time of using CAT were the influencing factors of the questions regarding the predictability of tooth movement through CAT and CAT knowledge that were demanded to be learned. CONCLUSIONS The predictability of difficult-to-be-achieved tooth movement through CAT is often overestimated by practitioners with limited clinical experience. Tailored education on CAT, especially managing troubleshooting cases and extraction cases, should be designed for all practitioners.
Collapse
Affiliation(s)
- Yanzi Gao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xuejun Sun
- Department of Biostatistics, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, North Carolina, USA
| | - Xinyu Yan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ziwei Tang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Wenli Lai
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Hu Long
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China; Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
| |
Collapse
|
5
|
Oliveira AC, Rocha AS, Leitão R, Maia M, Pinho T. Coronal Repercussions of the Maxillary Central Incisor Torque in the First Set of Aligners: A Retrospective Study. Dent J (Basel) 2023; 11:186. [PMID: 37623282 PMCID: PMC10453348 DOI: 10.3390/dj11080186] [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: 06/21/2023] [Revised: 07/17/2023] [Accepted: 07/31/2023] [Indexed: 08/26/2023] Open
Abstract
Coronal torque is one of the key factors in orthodontic treatment. An adequate torque value has an impact on aesthetics and soft tissue profile. The aim of this quantitative, comparative and observational longitudinal cohort study was to analyze the efficacy of the maxillary central incisor coronal torque in the Invisalign® system and evaluate the relation between coronal torque movement and patient's facial biotype. In total, 27 patients were selected. The planned movements (TP) were obtained from the Invisalign Doctor Site® using mathematical formulas that consider the T0 measurements. Pre-treatment (T0) and after full use of the first set of aligners (T1) scanners were evaluated using Geomagic® Control X TM by superimposing T0 and T1 models using a transverse plane and the long axis of the tooth crown. IBM® SPSS® software was used for statistical purposes. We found statistically significant differences between T0 and T1 in pro-inclination and retro-inclination, as well as between achieved and planned values in pro-inclination (p = 0.011). We verified that hyperdivergent clinical cases presented higher mean values of coronal torque, and hypodivergent cases presented lower values. In pro-inclination, the differences between the planned and achieved values were greater in hypodivergent cases and smaller in hyperdivergent cases. In retro-inclination, the differences between the planned and achieved values were greater in normodivergent cases and smaller in hypodivergent cases. This study highlights that inefficacy is more accentuated in pro-inclination. Aligners are an effective tool for producing coronal repercussions of torque movement, being more effective in retro-inclination.
Collapse
Affiliation(s)
- Ana Catarina Oliveira
- UNIPRO—Oral Pathology and Rehabilitation Research Unit, University Institute of Health Science (IUCS), CESPU, 4585-116 Gandra, Portugal; (A.C.O.); (A.S.R.); (R.L.)
| | - Ana Sofia Rocha
- UNIPRO—Oral Pathology and Rehabilitation Research Unit, University Institute of Health Science (IUCS), CESPU, 4585-116 Gandra, Portugal; (A.C.O.); (A.S.R.); (R.L.)
| | - Rita Leitão
- UNIPRO—Oral Pathology and Rehabilitation Research Unit, University Institute of Health Science (IUCS), CESPU, 4585-116 Gandra, Portugal; (A.C.O.); (A.S.R.); (R.L.)
| | - Manuela Maia
- IPMAIA—Instituto Politécnico da Maia, Avenida Carlos de Oliveira Campos, Castêlo da Maia, 4475-690 Maia, Portugal;
| | - Teresa Pinho
- UNIPRO—Oral Pathology and Rehabilitation Research Unit, University Institute of Health Science (IUCS), CESPU, 4585-116 Gandra, Portugal; (A.C.O.); (A.S.R.); (R.L.)
- IBMC—Molecular and Cellular Biology Institute, i3S—Health Innovation and Research Institute, University of Porto, 4200-135 Porto, Portugal
| |
Collapse
|
6
|
Lyu X, Cao X, Chen L, Liu Y, Li H, Hu C, Tan J. Accumulated biomechanical effects of mandibular molar mesialization using clear aligners with auxiliary devices: an iterative finite element analysis. Prog Orthod 2023; 24:13. [PMID: 37032410 PMCID: PMC10083150 DOI: 10.1186/s40510-023-00462-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/07/2023] [Indexed: 04/11/2023] Open
Abstract
BACKGROUND The biomechanics generated by the clear aligner (CA) material changes continuously during orthodontic tooth movement, but this factor remains unknown during the computer-aid design process and the predictability of molars movement is not as expected. Therefore, the purpose of this study was to propose an iterative finite element method to simulate the long-term biomechanical effects of mandibular molar mesialization (MM) in CA therapy under dual-mechanical systems. METHODS Three groups including CA alone, CA with a button, and CA with a modified lever arm (MLA) were created. Material properties of CA were obtained by in vitro mechanical experiments. MM was conducted by the rebound force exerted by CA material and the mesial elastic force (2N, 30° to the occlusal plane) applied to the auxiliary devices. Stress intensity and distribution on periodontal ligament (PDL), attachment, button and MLA, and displacement of the second molar (M2) during the iterations were recorded. RESULTS There was a significant difference between the initial and cumulative long-term displacement. Specifically, compared to the beginning, the maximum stress of PDL decreased by 90% on average in the intermediate and final steps. The aligner was the main mechanical system at first, and then, the additional system exerted by the button and MLA dominated gradually. The stress of attachments and auxiliary devices is mainly concentrated on their interfaces with the tooth. Additionally, MLA provided a distal tipping and extrusive moment, which was the only group that manifested a total mesial displacement of the root. CONCLUSIONS The innovatively designed MLA was more effective in reducing undesigned mesial tipping and rotation of M2 than the traditional button and CA alone, which provided a therapeutic method for MM. The proposed iterative method simulated tooth movement by considering the mechanical characteristic of CA and its long-term mechanical force changes, which will facilitate better movement prediction and minimize the failure rate.
Collapse
Affiliation(s)
- Xinwei Lyu
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Xing Cao
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Luxian Chen
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Yuyao Liu
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Huilin Li
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Cheng Hu
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Jiali Tan
- Department of Orthodontics, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China.
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510080, China.
- Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510080, China.
| |
Collapse
|
7
|
Yang Y, Yang R, Liu L, Zhang X, Jiang Q, Fan Q, Zhang H, Long H, Lai W. The effects of aligner anchorage preparation on mandibular first molars during premolar-extraction space closure with clear aligners: A finite element study. Am J Orthod Dentofacial Orthop 2023:S0889-5406(23)00098-7. [PMID: 37024337 DOI: 10.1016/j.ajodo.2022.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 12/01/2022] [Accepted: 12/01/2022] [Indexed: 04/08/2023]
Abstract
INTRODUCTION This study aimed to determine the effectiveness of different aligner anchorage preparations on mandibular first molars during premolar-extraction space closure with clear aligners and to assess the effects of different modes of Class II elastics on mandibular first molars. METHODS Finite element models were constructed on the basis of cone-beam computed tomography data from an orthodontic patient. The models comprised maxilla, mandible, maxillary and mandibular teeth without first premolars, periodontal ligaments, attachments and aligners. Tooth displacement tendencies were calculated using different aligner anchorage preparations and Class II elastics on the models from the same patient. Three group sets were designed on the basis of the positions of aligner cutouts and buttons (mesiobuccal, distobuccal and lingual). Four groups were established in each of the 3 group sets. Four groups were created: (1) no elastic traction + no anchorage preparation, (2) anchorage preparation only, (3) elastic traction only, and (4) elastic traction + anchorage preparation. Different aligner anchorage preparations (0°, 1°, 2°, 3°) were applied on mandibular second premolars and molars. The Class II traction force was set to 100 g. RESULTS With clear aligners, mandibular first molars were subject to mesial tipping, lingual tipping and intrusion. In the condition of no elastic traction, aligner anchorage preparation resulted in distal tipping, buccal tipping, and extrusion effect on mandibular first molars. Aligner anchorage preparation was more effective in the distal and lingual cutout groups than in the mesial cutout group. In the condition of Class II elastic traction, the bodily movement of mandibular first molars was achieved with a 3° anchorage preparation for the mesial cutout group and a 1.7° anchorage preparation for distal and lingual cutout groups. Absolute maximal anchorage was achieved with a 2° anchorage preparation for distal and lingual cutout groups. CONCLUSIONS Clear aligner therapy caused mesial tipping, lingual tipping and intrusion of mandibular first molars during premolar-extraction space closure. Aligner anchorage preparation effectively prevented mesial and lingual tipping of mandibular molars. Distal and lingual cutout modes were more effective than mesial cutout modes in aligner anchorage preparation. For each aligner stage (0.25 mm), 1.7° aligner anchorage preparation and Class II elastics with distal or lingual cutouts led to the bodily movement of mandibular first molars, whereas 2° anchorage preparation reached absolute maximal anchorage.
Collapse
Affiliation(s)
- Yi Yang
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ruicong Yang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China
| | - Lu Liu
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaoqi Zhang
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qingsong Jiang
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qi Fan
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Haoxin Zhang
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Hu Long
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
| | - Wenli Lai
- Department of Orthodontics, State Key Laboratory of Oral Diseases and National Clinical Center for Oral Research, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
| |
Collapse
|
8
|
Clear Aligners and Smart Eye Tracking Technology as a New Communication Strategy between Ethical and Legal Issues. Life (Basel) 2023; 13:life13020297. [PMID: 36836654 PMCID: PMC9967915 DOI: 10.3390/life13020297] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/26/2023] Open
Abstract
Smart eye-tracking technology (SEET) that determines visual attention using smartphones can be used to determine the aesthetic perception of different types of clear aligners. Its value as a communication and comprehension tool, in addition to the ethical and legal concerns which it entails, can be assessed. One hundred subjects (50 F, 50 M; age range 15-70) were equally distributed in non-orthodontic (A) and orthodontic (B) groups. A smartphone-based SEET app assessed their knowledge of and opinions on aligners. Subjects evaluated images of smiles not wearing aligners, with/without attachments and with straight/scalloped gingival margins, as a guided calibration step which formed the image control group. Subsequently, the subjects rated the same smiles, this time wearing aligners (experimental images group). Questionnaire data and average values for each group of patients, and images relating to fixation times and overall star scores, were analyzed using these tests: chi-square, t-test, Mann-Whitney U, Spearman's rho, and Wilcoxon (p < 0.05). One-way ANOVA and related post-hoc tests were also applied. Orthodontic patients were found to be better informed than non-orthodontic patients. Aesthetic perception could be swayed by several factors. Attachments scored lower in aesthetic evaluation. Lips distracted attention from attachments and improved evaluations. Attachment-free aligners were better rated overall. A more thorough understanding as to the opinions, expectations and aesthetic perception of aligners can improve communication with patients. Mobile SEET is remarkably promising, although it does require a careful medicolegal risk-benefit assessments for responsible and professional use.
Collapse
|
9
|
Ren L, Liu L, Wu Z, Shan D, Pu L, Gao Y, Tang Z, Li X, Jian F, Wang Y, Long H, Lai W. The predictability of orthodontic tooth movements through clear aligner among first-premolar extraction patients: a multivariate analysis. Prog Orthod 2022; 23:52. [PMID: 36581703 PMCID: PMC9800677 DOI: 10.1186/s40510-022-00447-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 11/02/2022] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The purpose was to determine the predictability of tooth movements through clear aligner among premolar extraction patients and to explore the effects of various factors on tooth movements. METHODS A total of 31 extraction patients (10 males and 20 females; age 14-44) receiving clear aligner treatment (Invisalign) were enrolled in this study. The actual post-treatment models and pre-treatment models were superimposed using the palatal area as a reference and registered with virtual post-treatment models. A paired t test was used to compare the differences between actual and designed tooth movements of maxillary first molars, canines, and central incisors. A multivariate linear mixed model was performed to examine the influence of variables on actual tooth movements. RESULTS Compared to the designed tooth movements, the following undesirable tooth movements occurred: mesial movement (2.2 mm), mesial tipping (5.4°), and intrusion (0.45 mm) of first molars; distal tipping (11.0°), lingual tipping (4.4°), and distal rotation of canines (4.9°); lingual tipping (10.6°) and extrusion (1.5 mm) of incisors. Age, crowding, mini-implant, overbite, and attachments have differential effects on actual tooth movements. Moreover, vertical rectangular attachments on canines are beneficial in achieving more predictable canine and incisor tooth movements over optimized attachments. Lingual tipping and extrusion of incisors were significantly influenced by the interaction effects between incisor power ridge and different canine attachments (p < 0.05). CONCLUSIONS Incisors, canines, and first molars are subject to unwanted tooth movements with clear aligners among premolar extraction patients. Age, crowding, mini-implant, overbite, and attachments influence actual tooth movements. Moreover, vertical rectangular attachments on canines are beneficial in achieving more predictable incisor tooth movements over optimized canine attachments.
Collapse
Affiliation(s)
- Linghuan Ren
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China ,grid.32566.340000 0000 8571 0482Hospital of Stomatology, Lanzhou University, Lanzhou, Gansu Province China
| | - Lu Liu
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Zhouqiang Wu
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Di Shan
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Lingling Pu
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Yanzi Gao
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Ziwei Tang
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Xiaolong Li
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Fan Jian
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Yan Wang
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Hu Long
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| | - Wenli Lai
- grid.13291.380000 0001 0807 1581State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041 China
| |
Collapse
|
10
|
Chi J, Yang L, Liu Y, Yang J, Deng J. Biomechanical Characteristics of Maxillary Molar Distalization Using Different Attachments with Clear Aligners: A 3-Dimensional Finite Element Analysis. J BIOMATER TISS ENG 2022. [DOI: 10.1166/jbt.2022.3094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study aimed to compare the biomechanical characteristics of maxillary teeth in molar distalization with different orthodontic attachments. A 3-dimensional finite model of maxillary molar distalization with clear aligners was generated by computed tomography and contained different
components. Four models—non-attachment (model A), horizontal rectangular attachment (model B), vertical rectangular attachment (model C), and combined attachment (model D)—were set up. The modalities of molar distalization were simulated using a finite element analysis. The results
showed that the minimum displacement (rotation center) of the second molar in models A and B was located at the root furcation. In model C, the minimum displacement was located in the middle third of the palatal root. In model D, the minimum displacement was located at the apical third of
the root. The anchorage teeth in all the four groups tended to have mesial tipping movement. Models B and D had more uniform stress distribution of the periodontal ligament than models A and C. Models with attachment had a larger tooth displacement pattern than that without attachment. Collectively,
if molar distalization is planned before treatment, the appropriate application of attachments can help achieve the desired tooth movements more efficiently.
Collapse
Affiliation(s)
- Jingwen Chi
- School of Stomatology, Qingdao University, Qingdao, 266003, China
| | - Lixia Yang
- School of Stomatology, Qingdao University, Qingdao, 266003, China
| | - Yicong Liu
- School of Stomatology, Qingdao University, Qingdao, 266003, China
| | - Jianjun Yang
- Department of Oral and Maxillofacial Surgery, Affiliated Hospital, Qingdao University, Qingdao, 266001, China
| | - Jing Deng
- School of Stomatology, Qingdao University, Qingdao, 266003, China
| |
Collapse
|
11
|
Wang Q, Dai D, Wang J, Chen Y, Zhang C. Biomechanical analysis of effective mandibular en-masse retraction using Class II elastics with a clear aligner: a finite element study. Prog Orthod 2022; 23:23. [PMID: 35811318 PMCID: PMC9271451 DOI: 10.1186/s40510-022-00417-4] [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: 02/03/2022] [Accepted: 05/05/2022] [Indexed: 11/13/2022] Open
Abstract
Background This study aimed to evaluate the displacement and stress distribution of mandibular dentition by various positions of the Class II elastics during en-masse retraction in clear aligner therapy. Methods Models including a mandibular dentition (without first premolars), periodontal ligament (PDL), mandible, as well as attachments, aligners and buttons were constructed and imported into Ansys Workbench 2019 (ANSYS, USA) to generate the three-dimensional (3D) finite element model. Six combinations were created: (1) aligner alone (control), (2)-(5) Class II elastics with buttons placed on the mesiobuccal (MB), distobuccal (DB), mesiolingual (ML) and distolingual (DL) surface of the mandibular first molar, and (6) Class II elastics with a button on the aligner corresponding to the mesiobuccal surface of the mandibular first molar (AMB). The elastic force was set to 2 N for simulations. Results The central incisors appeared lingual tipping in the six models. The lingual crown movement of the central incisors was 0.039 mm, 0.034 mm, 0.034 mm, 0.042 mm, 0.041 mm, and 0.034 mm for control model, MB model, DB model, ML model, DL model, and AMB model, respectively. The first molars showed mesial tipping in the six models. The mesial movement of the mesiobuccal cusps of the first molars was 0.045 mm, 0.060 mm, 0.063 mm, 0.048 mm, 0.051 mm, and 0.055 mm for control model, MB model, DB model, ML model, DL model, and AMB model, respectively. Conclusions Class II elastics reduced lingual tipping of anterior teeth but aggravated mesial tipping of posterior teeth. Mesiolingual elastics developed minimum mesial tipping of the posterior teeth. When Class II elastics are required, attaching elastics on the mesiolingual surface of the mandibular first molar is recommended to prevent mandibular anchorage loss.
Collapse
|
12
|
Liu L, Song Q, Zhou J, Kuang Q, Yan X, Zhang X, Shan Y, Li X, Long H, Lai W. The effects of aligner overtreatment on torque control and intrusion of incisors for anterior retraction with clear aligners: A finite-element study. Am J Orthod Dentofacial Orthop 2022; 162:33-41. [DOI: 10.1016/j.ajodo.2021.02.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 02/01/2021] [Accepted: 02/01/2021] [Indexed: 01/22/2023]
|