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Sabbagh H, Haas E, Baumert U, Seidel CL, Hötzel L, Wichelhaus A. Biomechanical Simulation of Orthodontic En-Bloc Retraction Comparing Compound Technique and Sliding Mechanics Using a HOSEA Robotic Device. Bioengineering (Basel) 2024; 11:153. [PMID: 38391639 PMCID: PMC10886252 DOI: 10.3390/bioengineering11020153] [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: 01/15/2024] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/24/2024] Open
Abstract
En-bloc retraction is a common procedure in orthodontic therapy. The application of palatal root torque moments is required to control incisor inclination during retraction, yet studies comparing forces and moments with respect to different mechanics are lacking. This study aimed to investigate the forces and moments during orthodontic en-bloc retraction using a robotic biomechanical simulation system, comparing two distinct approaches: (I) compound technique [stainless steel (SS) combined with nickel-titanium (NiTi)] using industrially pretorqued retraction-torque-archwires (RTA) in combination with NiTi closed coil springs; (II) conventional sliding mechanics using SS archwires with manually applied anterior twist bends in combination with elastic chains. Two dimensions (0.017" × 0.025" and 0.018" × 0.025") and ten archwires per group were investigated using 0.022" slot self-ligating brackets. Kruskal-Wallis tests with a significance level of α = 0.05 were conducted. The biomechanical simulation showed that en-bloc retraction was characterized by a series of tipping and uprighting movements, differing significantly regarding the examined mechanics. Collateral forces and moments occurred in all groups. Notably, RTA exhibited fewer extrusive forces. The most bodily movement was achieved with the compound technique and the 0.018" × 0.025" RTA. Sliding mechanics exhibited maximum palatal root torque moments of more than 20 Nmm, exceeding recommended values.
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Affiliation(s)
- Hisham Sabbagh
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Ellen Haas
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Uwe Baumert
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Corinna Lesley Seidel
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Linus Hötzel
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Andrea Wichelhaus
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
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Mall V, Bhosale V, Vichare G, Patil A. Comparison of stainless steel and titanium-molybdenum alloy closing loop archwires using numeric simulation model based on finite element method. Am J Orthod Dentofacial Orthop 2023; 164:e129-e138. [PMID: 37656072 DOI: 10.1016/j.ajodo.2023.06.010] [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: 06/01/2022] [Revised: 06/01/2023] [Accepted: 06/01/2023] [Indexed: 09/02/2023]
Abstract
INTRODUCTION The objective of this study was to determine and compare the moment-to-force (Mc/F) ratio and the type of tooth movement generated in the anterior and posterior segments in orthodontic space closure with stainless steel and titanium-molybdenum alloy loop archwires. METHODS Three-dimensional model of the maxilla from which the first premolar was extracted, 18 × 25-mil slot stainless steel brackets, and 16 × 22-mil stainless steel and β titanium-molybdenum alloy (TMA) closing loop archwires with anterior gable bend of 15° and posterior gable bend of 25° were constructed. The archwires were engaged in the brackets, and 1-mm activations were carried out, which were repeated 5 times. The anterior and posterior segment Mc/F ratio and the type of tooth movement generated by the 2 wires were compared. RESULTS It was found that the Mc/F ratio for the anterior segment was approximately 5 mm, and for posterior teeth was approximately 10 mm for both stainless steel and TMA closing loop archwire. The anterior teeth exhibited controlled tipping, whereas the posterior teeth showed bodily tooth movement, which was in accordance with the Mc/F ratio that was obtained. CONCLUSIONS The Mc/F ratio and the type of tooth movement exhibited by stainless steel and TMA closing loop archwires were similar in both anterior and posterior segments.
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Affiliation(s)
- Vaishali Mall
- Bharati Vidyapeeth (Deemed to be University) Dental College and Hospital, Navi Mumbai, Maharashtra, India.
| | - Veera Bhosale
- Department of Orthodontics and Dentofacial Orthopedics, Bharati Vidyapeeth (Deemed to be University) Dental College and Hospital, Pune, Maharashtra, India
| | - Gauri Vichare
- VSPM Dental College and Research Centre, Nagpur, Maharashtra, India
| | - Amol Patil
- Bharati Vidyapeeth (Deemed to be University) Dental College and Hospital, Navi Mumbai, Maharashtra, India
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Haas E, Schmid A, Stocker T, Wichelhaus A, Sabbagh H. Force-Controlled Biomechanical Simulation of Orthodontic Tooth Movement with Torque Archwires Using HOSEA (Hexapod for Orthodontic Simulation, Evaluation and Analysis). Bioengineering (Basel) 2023; 10:1055. [PMID: 37760157 PMCID: PMC10525810 DOI: 10.3390/bioengineering10091055] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
This study aimed to investigate the dynamic behavior of different torque archwires for fixed orthodontic treatment using an automated, force-controlled biomechanical simulation system. A novel biomechanical simulation system (HOSEA) was used to simulate dynamic tooth movements and measure torque expression of four different archwire groups: 0.017″ x 0.025″ torque segmented archwires (TSA) with 30° torque bending, 0.018″ x 0.025″ TSA with 45° torque bending, 0.017″ x 0.025″ stainless steel (SS) archwires with 30° torque bending and 0.018″ x 0.025″ SS with 30° torque bending (n = 10/group) used with 0.022″ self-ligating brackets. The Kruskal-Wallis test was used for statistical analysis (p < 0.050). The 0.018″ x 0.025″ SS archwires produced the highest initial rotational torque moment (My) of -9.835 Nmm. The reduction in rotational moment per degree (My/Ry) was significantly lower for TSA compared to SS archwires (p < 0.001). TSA 0.018″ x 0.025″ was the only group in which all archwires induced a min. 10° rotation in the simulation. Collateral forces and moments, especially Fx, Fz and Mx, occurred during torque application. The measured forces and moments were within a suitable range for the application of palatal root torque to incisors for the 0.018″ x 0.025″ archwires. The 0.018″ x 0.025″ TSA reliably achieved at least 10° incisal rotation without reactivation.
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Affiliation(s)
| | | | | | | | - Hisham Sabbagh
- Department of Orthodontics and Dentofacial Orthopedics, LMU University Hospital, LMU Munich, Goethestraße 70, 80336 Munich, Germany; (E.H.); (A.S.); (T.S.); (A.W.)
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Kawamura J, Ojima K, Nanda R. Effect of attachment type on distal bodily movement of the maxillary canine in aligner orthodontics: a finite element study. Angle Orthod 2023; 93:566-571. [PMID: 37079796 PMCID: PMC10575637 DOI: 10.2319/120121-879.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 03/01/2023] [Indexed: 04/22/2023] Open
Abstract
OBJECTIVES To clarify the effect of attachment types on bodily movement of the maxillary canine in aligner orthodontics. MATERIALS AND METHODS Using an aligner, the canine was moved bodily by 0.1 mm distally as a target position. Orthodontic tooth movement was simulated using the finite element method (FEM). The alveolar socket was displaced in the same manner as the initial movement caused by elastic deformation of the periodontal ligament. First, the initial movement was calculated, and then the alveolar socket was displaced in the same direction and with the same magnitude as the initial movement. These calculations were repeated to move the teeth after placement of the aligner. The teeth and the alveolar bone were assumed to be rigid bodies. A FEM model of the aligner was made based on the crown surfaces. The thickness of the aligner was 0.45 mm, and its Young's modulus was 2 GPa. Three types of attachments-semicircular couple, vertical rectangular, and horizontal rectangular-were placed on the canine crown. RESULTS Regardless of the type of attachment, upon placement of the aligner on the dentition the crown of the canine moved to the target position, while the apex hardly moved. That is, the canine tipped and rotated. After repeating the calculation, the canine became upright and moved bodily regardless of the attachment type. In the aligner without an attachment, the canine did not become upright. CONCLUSIONS There was almost no difference among attachment types in terms of achieving bodily movement of the canine.
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Affiliation(s)
- Jun Kawamura
- Corresponding author: Jun Kawamura, DDS, PhD, Kawamura Dental Office, 4-21 Sodensakae-machi Gifu City, Gifu, 502-0847, Japan (e-mail: )
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Three-dimensional comparison of the effects of sliding mechanics in labial and lingual orthodontics using the finite element method. Am J Orthod Dentofacial Orthop 2022; 162:24-32. [DOI: 10.1016/j.ajodo.2021.02.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 02/01/2021] [Accepted: 02/01/2021] [Indexed: 11/21/2022]
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Liu Z, Sun T, Fan Y. Biomechanical influence of anchorages on orthodontic space closing mechanics by sliding method. Med Biol Eng Comput 2020; 58:1091-1097. [PMID: 32162244 DOI: 10.1007/s11517-020-02149-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 02/19/2020] [Indexed: 11/27/2022]
Abstract
This study aims to analyse the stress distributions and initial displacements of teeth during the space closing stage through a three-dimensional finite element method. Computed tomography images of a patient were used to reconstruct the detailed teeth and alveolar bone, and brackets with stainless steel archwire were modelled according to the orthodontic prescriptions. The second premolars and first molars were chosen as the anchorages in the model 6-force, with buccal tubes attached to the second molars in the model 6-force-7, and the second molars as additional anchorages in the model 7-force. The results indicated that a movement of lingual lateral inclination occurred on the incisors during the retraction, and the frictional force between the teeth and the archwire significantly reduced the stress on the teeth and periodontal structures. Graphical abstract Malocclusion is one of the most common issue in dentistry with high prevalence and orthodontic treatment need. The extraction of first premolar teeth was normally needed at the beginning of the treatment. And the straight wire appliance together with the sliding mechanics was used for space closure at the end of the treatment. However, side effects like root resorption also found after the surgery. Biomechanically, the stress distributions and initial displacements of teeth during space closing stage might be a crucial factor contributed to those undesirable side effects. And different selections of anchorages might alter the biomechanical environment during the treatment. Thus, the purpose of the current study was to analyse the stress distributions and initial displacements, with the different anchorage selections, of teeth during space closing stage through 3D finite element method.
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Affiliation(s)
- Zhan Liu
- Key Lab for Biomechanical Engineering of Sichuan Province, Sichuan University, Chengdu, China
| | - Tinghui Sun
- Key Lab for Biomechanical Engineering of Sichuan Province, Sichuan University, Chengdu, China
| | - Yubo Fan
- School of Biological Science and Medical Engineering, Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China.
- Beijing Key Laboratory of Rehabilitation Engineering for Elderly, National Research Center for Rehabilitation Technical Aids, Beijing, China.
- Yubo Fan, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
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Park CS, Yu HS, Cha JY, Mo SS, Lee KJ. Effect of archwire stiffness and friction on maxillary posterior segment displacement during anterior segment retraction: A three-dimensional finite element analysis. Korean J Orthod 2019; 49:393-403. [PMID: 31815107 PMCID: PMC6883216 DOI: 10.4041/kjod.2019.49.6.393] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/16/2019] [Accepted: 08/09/2019] [Indexed: 11/20/2022] Open
Abstract
Objective Sliding mechanics using orthodontic miniscrews is widely used to stabilize the anchorage during extraction space closure. However, previous studies have reported that both posterior segment displacement and anterior segment displacement are possible, depending on the mechanical properties of the archwire. The present study aimed to investigate the effect of archwire stiffness and friction change on the displacement pattern of the maxillary posterior segment during anterior segment retraction with orthodontic miniscrews in sliding mechanics. Methods A three-dimensional finite element model was constructed. The retraction point was set at the archwire level between the lateral incisor and canine, and the orthodontic miniscrew was located at a height of 8 mm from the archwire between the second premolar and first molar. Archwire stiffness was simulated with rectangular stainless steel wires and a rigid body was used as a control. Various friction levels were set for the surface contact model. Displacement patterns for the posterior and anterior segments were compared between the conditions. Results Both the anterior and posterior segments exhibited backward rotation, regardless of archwire stiffness or friction. Among the conditions tested in this study, the least undesirable rotation was found with low archwire stiffness and low friction. Conclusions Posterior segment displacement may be unavoidable but reducing the stiffness and friction of the main archwire may minimize unwanted rotations during extraction space closure.
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Affiliation(s)
- Choon-Soo Park
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea
| | - Hyung-Seog Yu
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea
| | - Jung-Yul Cha
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea
| | - Sung-Seo Mo
- Division of Orthodontics, Department of Dentistry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Kee-Joon Lee
- Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea.,Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea
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Cozzani M, Sadri D, Nucci L, Jamilian P, Pirhadirad AP, Jamilian A. The effect of Alexander, Gianelly, Roth, and MBT bracket systems on anterior retraction: a 3-dimensional finite element study. Clin Oral Investig 2019; 24:1351-1357. [PMID: 31352519 DOI: 10.1007/s00784-019-03016-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 07/10/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVES The aims of this study were to compare the effect of 4 bracket systems including Alexander, Roth, MBT, and Gianelly on upper anterior retraction and to quantify the amount of torque loss ratio in sliding mechanics by help of a 3-dimensional (3D) finite element method. METHOD AND MATERIALS 3D FEM models were constructed in order to simulate anterior incisor retraction in first premolar extraction case. Displacement, stress, and strain on the incisal edge and apex of maxillary central incisor were calculated when 1-, 2-, and 3-N retraction forces were applied. Torque loss ratio was calculated by measuring the displacement of the teeth at crown tip and root apex in all 4 bracket systems on upper central incisor. RESULTS Uncontrolled lingual crown tipping of the incisor was observed in all bracket systems. The crown moved lingually by 9.5 μm and the root labially by 4.5 μm in MBT system with 3-N retraction force. The amount of crown movement was 8 μm and the root displacement was 4 μm in Gianelly system with the same retraction force. Torque loss ratio was 1.46 in Alexander and Gianelly with 3-N retraction force. However, the amount of torque loss ratio was 1.47 in MBT and Roth with the same retraction force. CONCLUSIONS AND CLINICAL RELEVANCE Uncontrolled tipping was the least in Gianelly and was the highest in MBT. The amount of torque loss ratio was the lowest in Gianelly and Alexander systems and the amount of torque loss ratio was the highest in MBT system.
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Affiliation(s)
| | - Donia Sadri
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
| | - Ludovica Nucci
- Dental School, Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Parsa Jamilian
- International Baccalaureate Program, Danube International School, Vienna, Austria
| | - Amir Parham Pirhadirad
- Department of Bio Medical Engineering, Faculty of Bio Medical Engineering, Science and Research Branch, Cranio Maxillofacial Research Center, Islamic Azad University, Tehran, Iran
| | - Abdolreza Jamilian
- Department of Orthodontics, Faculty of Dentistry, Cranio Maxillofacial Research Center, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
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Gómez-Gómez SL, Sánchez-Obando N, Álvarez-Castrillón MA, Montoya-Goez Y, Ardila CM. Comparison of frictional forces during the closure of extraction spaces in passive self-ligating brackets and conventionally ligated brackets using the finite element method. J Clin Exp Dent 2019; 11:e439-e446. [PMID: 31275516 PMCID: PMC6599702 DOI: 10.4317/jced.55739] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/13/2019] [Indexed: 11/12/2022] Open
Abstract
Background This study compared the frictional force resulting from the bracket/archwire interface and the stress at the root/periodontal ligament/bone interface, between passive self-ligating brackets and conventionally ligated brackets, during the space closure stage. Material and Methods A cone beam tomography was taken to a female patient that required extraction of upper first premolars and passive self-ligating system; three months after its activation, a cone beam tomography was taken again. The designs of the maxillary bone and the entire system were possible through tomography images and stereomicroscopic photographs. Validation of the Finite Element Method (FEM) was achieved comparing the amount of movement seen through tomography images and the FEM. Space closure was simulated for each system through the FEM and a comparison was made between the frictional force at the bracket/archwire interface, and the root/periodontal ligament/bone interface. Results The most significant representation of frictional force at bracket/archwire interface and bone stress was found at the conventionally ligated system, while the passive self-ligating system accounted for the highest distribution of stress over the root. Conclusions The FEM is an accurate tool used to quantify frictional force and stress concentration during the orthodontic closure. The passive self-ligating system was seen less frictional during the closure state compared to conventional brackets. Key words:Friction, orthodontic bracket, finite element analysis.
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Affiliation(s)
- Sandra-Liliana Gómez-Gómez
- Orthodontics; Master in Epidemiology; Assistant Professor, School of Dentistry, Universidad de Antioquia
| | | | | | - Yesid Montoya-Goez
- Civil Engineer. Master of Materials Science; Assistant Professor, Escuela de Ingeniería de Antioquia
| | - Carlos M Ardila
- Periodontist. Ph.D in Epidemiology; Biomedical Stomatology Group, Universidad de Antioquia, Medellín, Colombia. Department of Periodontology, School of Dentistry, Universidad de Antioquia
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Tunçer Nİ, Köseoğlu-Seçgin C, Arman-Özçırpıcı A. An unusual case of invasive cervical resorption after piezosurgery-assisted en masse retraction. Am J Orthod Dentofacial Orthop 2019; 156:137-147. [PMID: 31256827 DOI: 10.1016/j.ajodo.2019.02.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 02/01/2019] [Accepted: 02/01/2019] [Indexed: 11/30/2022]
Abstract
A 16-year-old patient sought orthodontic correction for profile improvement and labially inclined maxillary incisors. She had Class II malocclusion, protrusive maxillary and mandibular incisors, and increased overjet and overbite with an American Board of Orthodontics discrepancy index value of 25. She was treated with maxillary premolar extractions and miniscrew-supported en masse retraction assisted with piezoincisions. Extraction spaces (7.5 mm per side) were closed with maximum anchorage in 10 months. Total treatment time was 23 months. Twenty-seven months after debonding, a pink spot was noted at the buccocervial region of the left central incisor. Radiographic evaluation on cone-beam computed tomographic scans revealed a severe case of invasive cervical resorption on both central incisors, around which the piezosurgical cuts had been made. Treatment proceeded with a nonintervention approach and the affected teeth were reinforced with a lingual retainer.
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Affiliation(s)
- Nilüfer İrem Tunçer
- Department of Orthodontics, Faculty of Dentistry, Başkent University, Ankara, Turkey.
| | - Cansu Köseoğlu-Seçgin
- Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Başkent University, Ankara, Turkey
| | - Ayça Arman-Özçırpıcı
- Department of Orthodontics, Faculty of Dentistry, Başkent University, Ankara, Turkey
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Ruenpol N, Sucharitpwatskul S, Wattanawongskun P, Charoenworaluck N. Force direction using miniscrews in sliding mechanics differentially affected maxillary central incisor retraction: Finite element simulation and typodont model. J Dent Sci 2019; 14:138-145. [PMID: 31205605 PMCID: PMC6558348 DOI: 10.1016/j.jds.2019.01.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/02/2018] [Indexed: 11/29/2022] Open
Abstract
Background/purpose En masse retraction was still controversy in orthodontics. The aim of this study was to investigate the effect of force directions created by different miniscrew positions and lever arm heights on maxillary central incisor movement using Finite Element (FE) simulation and a Typodont model. Materials and methods A typodont model and 3-dimensional FE were used to simulate en masse anterior teeth retraction in sliding mechanics. The lever arm and the miniscrew positions were varied to change the force direction. The maxillary central incisor displacement was recorded and analyzed. Results The typodont results revealed that miniscrew vertical position and lever arm height affected the type of tooth movement. The best control in the vertical plane was achieved by a 7 mm lever arm height and miniscrew 9 mm from the archwire. When the lever arm height and miniscrew were 7 mm from the archwire, the tooth extruded. When the lever arm height was 9 mm and the miniscrew was 7 or 9 mm from the archwire, the tooth intruded. The FE stimulation determined that near bodily movement of the maxillary central incisor was achieved when the lever arm height and miniscrew was 9 mm from the archwire. The highest strain distribution in the periodontal ligament was observed at the apical third of the lateral incisor. Conclusion In en masse retraction, the appropriate direction of force or the height of the miniscrew and the lever arm may enable orthodontists to maintain better control of the anterior teeth in sliding mechanics.
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Affiliation(s)
- Nantaporn Ruenpol
- Faculty of Dentistry, Thammasat University, Pathum Thani, 12120, Thailand
| | | | - Prasit Wattanawongskun
- National Metal and Materials Technology Center, Thailand Science Park, Pathum Thani, 12120, Thailand
| | - Nongluck Charoenworaluck
- Faculty of Dentistry, Thammasat University, Pathum Thani, 12120, Thailand
- Corresponding author. Fax: +66 2 986 9205.
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Cozzani M, Azizi A, Eslami S, Darnahal A, Pirhadirad A, Jamilian A. 3-dimensional finite element analysis of the outcomes of Alexander, Gianelly, Roth and MBT bracket prescription. Int Orthod 2019; 17:45-52. [PMID: 30773446 DOI: 10.1016/j.ortho.2019.01.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The purpose of this study was to compare the effect of a 4-bracket system including Alexander, Roth, MBT (Maxillary Transverse Bioadaptation), and Gianelly on the upper anterior tooth movement in sliding mechanics with the help of a 3-Dimensional (3D) Finite Element Method. METHODS Displacement, stress, strain, centre of rotation and resistance on the incise edge and apex of the maxillary central incisor were calculated when 100, 200, 300, 400grams of retraction force were applied. RESULTS The amount of incise edge displacement was 2.609×10-4mm 2.682×10-4mm 2.875×10-4mm and 2.881×10-4mm in Alexander, Gianelly, Roth and MBT respectively with 100gr of retraction force. The value of apex root movement was 3.485×10-4mm 3.547×10-4mm 3.852×10-4mm and 3.864×10-4mm in Alexander, Gianelly, Roth and MBT respectively with 400g of retraction force. CONCLUSIONS The MBT system had the maximum apex root and incisal edge movement in all 100, 200, 300, 400grams of retraction force. The Alexander system had the lowest apex and incisal edge movement in all retraction forces.
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Affiliation(s)
- Mauro Cozzani
- Medical and Rehabilitation Area, Dental Sciences Section, United Campus of Malta HEI, Malta, USA
| | - Arash Azizi
- Department of Oral and Maxillofacial Medicine, Tehran Medical Sciences, Craniomaxillofacial Research Centre, Islamic Azad University, Tehran, Iran
| | - Sara Eslami
- Department of orthodontics, Dental School, Craniomaxillofacial Research Centre, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Alireza Darnahal
- Department of orthodontics, Dental School, Craniomaxillofacial Research Centre, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Amirparham Pirhadirad
- Department of Bio Medical Engineering, Faculty of Bio Medical Engineering, Science and Research Branch, Tehran Dental Branch, Cranio maxillofacial Research Centre, Islamic Azad University, Tehran, Iran
| | - Abdolreza Jamilian
- Department of orthodontics, Dental School, Craniomaxillofacial Research Centre, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
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Kawamura J, Tamaya N. A finite element analysis of the effects of archwire size on orthodontic tooth movement in extraction space closure with miniscrew sliding mechanics. Prog Orthod 2019; 20:3. [PMID: 30663006 PMCID: PMC6339866 DOI: 10.1186/s40510-018-0255-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 12/04/2018] [Indexed: 11/27/2022] Open
Abstract
Background Sliding mechanics with miniscrews is recently used for extraction space closure. The purpose of this study was to elucidate how and why the archwire size affects long-term tooth movement in miniscrew sliding mechanics. Methods Long-term orthodontic tooth movements were simulated based on a remodeling law of the alveolar bone by using a finite element method, in which the bracket rotated freely within a clearance gap (a play) of the archwire-bracket slot. The archwire size was changed to 0.021, 0.018, and 0.016 in. for the 0.022-in. bracket. Result Lingual crown tipping and extrusion of the incisors increased with decreasing the archwire size. Movements of the posterior teeth were approximately the same irrespective of archwire size. Conclusions When decreasing the archwire size, a play of the archwire-bracket slot, as well as the elastic deformation of the archwire, resulted in lingual tipping of the incisors. This tipping led to extrusion of the incisors.
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Affiliation(s)
- Jun Kawamura
- Kawamura Dental Office, 4-21 Sodensakae-machi, Gifu, 502-0847, Japan.
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Hwang M, Ahn HW, Kwon SY, Choi JH, Kim SH, Nelson G. Control of anterior segment using an antero-posterior lingual sliding retraction system: a preliminary cone-beam CT study. Prog Orthod 2018; 19:2. [PMID: 29333593 PMCID: PMC5767571 DOI: 10.1186/s40510-017-0202-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This study was performed to evaluate the treatment effects of the antero-posterior lingual retractor (APLR), focusing on the 3-dimensional (3D) tooth movement of the maxillary anterior teeth and their alveolar bone levels. METHODS En masse retraction was performed using either the C-lingual retractor (CLR, C-group, n = 9) or the antero-posterior lingual retractor (APLR, AP-group, n = 8). We evaluated 3D movement of the maxillary anterior teeth and alveolar bone levels, root length of the central incisors, long axes of the maxillary canines, and occlusal plane changes from CBCT images. RESULTS After retraction, the central incisors were more significantly intruded and their root apex was more retracted in the AP-group. The long axis of the canine was well maintained in the AP-group. There were no differences in the steepness of occlusal plane and the incidence of alveolar bone loss or of root resorption during en masse retraction with the two retractors. CONCLUSIONS The clockwise bowing effect of the anterior segment was less with the APLR, which prevented unwanted canine movement.
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Affiliation(s)
- Min Hwang
- Department of Orthodontics, Graduate School, Kyung Hee University, #1 Hoegi-dong, Dongdaemun-gu, Seoul, 130-701, Republic of Korea
| | - Hyo-Won Ahn
- Department of Orthodontics, Graduate School, Kyung Hee University, #1 Hoegi-dong, Dongdaemun-gu, Seoul, 130-701, Republic of Korea
| | - Soon-Yong Kwon
- Department of Orthodontics, Graduate School, Kyung Hee University, #1 Hoegi-dong, Dongdaemun-gu, Seoul, 130-701, Republic of Korea
| | - Jeong-Ho Choi
- Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Seong-Hun Kim
- Department of Orthodontics, Graduate School, Kyung Hee University, #1 Hoegi-dong, Dongdaemun-gu, Seoul, 130-701, Republic of Korea.
| | - Gerald Nelson
- Division of Orthodontics, Department of Orofacial Science, University of California San Francisco, San Francisco, CA, USA
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Hamanaka R, Yamaoka S, Anh TN, Tominaga JY, Koga Y, Yoshida N. Numeric simulation model for long-term orthodontic tooth movement with contact boundary conditions using the finite element method. Am J Orthod Dentofacial Orthop 2017; 152:601-612. [PMID: 29103438 DOI: 10.1016/j.ajodo.2017.03.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/01/2017] [Accepted: 03/01/2017] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Although many attempts have been made to simulate orthodontic tooth movement using the finite element method, most were limited to analyses of the initial displacement in the periodontal ligament and were insufficient to evaluate the effect of orthodontic appliances on long-term tooth movement. Numeric simulation of long-term tooth movement was performed in some studies; however, neither the play between the brackets and archwire nor the interproximal contact forces were considered. The objectives of this study were to simulate long-term orthodontic tooth movement with the edgewise appliance by incorporating those contact conditions into the finite element model and to determine the force system when the space is closed with sliding mechanics. METHODS We constructed a 3-dimensional model of maxillary dentition with 0.022-in brackets and 0.019 × 0.025-in archwire. Forces of 100 cN simulating sliding mechanics were applied. The simulation was accomplished on the assumption that bone remodeling correlates with the initial tooth displacement. RESULTS This method could successfully represent the changes in the moment-to-force ratio: the tooth movement pattern during space closure. CONCLUSIONS We developed a novel method that could simulate the long-term orthodontic tooth movement and accurately determine the force system in the course of time by incorporating contact boundary conditions into finite element analysis. It was also suggested that friction is progressively increased during space closure in sliding mechanics.
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Affiliation(s)
- Ryo Hamanaka
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| | - Satoshi Yamaoka
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Tuan Nguyen Anh
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Jun-Ya Tominaga
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yoshiyuki Koga
- Department of Orthodontics, Nagasaki University Hospital, Nagasaki, Japan.
| | - Noriaki Yoshida
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
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Andrade I. Frictionless segmented mechanics for controlled space closure. Dental Press J Orthod 2017; 22:98-109. [PMID: 28444016 PMCID: PMC5398848 DOI: 10.1590/2176-9451.22.1.098-109.bbo] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 12/16/2016] [Indexed: 05/29/2023] Open
Abstract
Extraction spaces may be needed to achieve specific orthodontic goals of positioning the dentition in harmony with the craniofacial complex. However, the fundamental reality that determines the occlusion final position is the control exerted by the orthodontist while closing the extraction spaces. A specific treatment objective may require the posterior teeth to remain in a constant position anteroposteriorly as well as vertically, while the anterior teeth occupy the entire extraction site. Another treatment objective may require the opposite, or any number of intentional alternatives of extraction site closure. The present case report describes a simple controlled segmented mechanic system that permitted definable and predictable force systems to be applied and allowed to predict the treatment outcome with confidence. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) in partial fulfillment of the requirements for Diplomate certification.
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17
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Root resorption of maxillary incisors retracted with and without skeletal anchorage. Am J Orthod Dentofacial Orthop 2017; 151:397-406. [DOI: 10.1016/j.ajodo.2016.06.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 06/01/2016] [Accepted: 06/01/2016] [Indexed: 01/16/2023]
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18
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En-masse protraction of mandibular posterior teeth into missing mandibular lateral incisor spaces using a fixed functional appliance. Am J Orthod Dentofacial Orthop 2016; 150:864-875. [PMID: 27871713 DOI: 10.1016/j.ajodo.2015.10.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 10/01/2015] [Accepted: 10/01/2015] [Indexed: 11/23/2022]
Abstract
Protraction of mandibular posterior teeth requiring absolute anchorage has always been a challenge, especially when the space is located in the anterior region, since more teeth must be protracted. Traditionally, skeletal anchorage devices have been used for anchorage reinforcement during protraction. However, drawbacks such as requirement of a surgical step, inability to tolerate heavy forces, and patient willingness to undergo such surgical procedures can be limiting factors. Additionally, the mechanics involved can sometimes create undesirable side effects, thereby limiting their application in such situations. This report describes the use of a fixed functional appliance as an anchorage-reinforcement device for en-masse protraction of mandibular posterior teeth into a missing lateral incisor space.
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Lee D, Heo G, El-Bialy T, Carey JP, Major PW, Romanyk DL. Initial forces experienced by the anterior and posterior teeth during dental-anchored or skeletal-anchored en masse retraction in vitro. Angle Orthod 2016; 87:549-555. [PMID: 27830931 DOI: 10.2319/080916-616.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE To investigate initial forces acting on teeth around the arch during en masse retraction using an in vitro Orthodontic SIMulator (OSIM). MATERIALS AND METHODS The OSIM was used to represent the full maxillary arch in a case wherein both first premolars had been extracted. Dental and skeletal anchorage to a posted archwire and skeletal anchorage to a 10-mm power arm were all simulated. A 0.019 × 0.025-inch stainless steel archwire was used in all cases, and 15-mm light nickel-titanium springs were activated to approximately 150 g on both sides of the arch. A sample size of n = 40 springs were tested for each of the three groups. Multivariate analysis of variance (α = 0.05) was used to determine differences between treatment groups. RESULTS In the anterior segment, it was found that skeletal anchorage with power arms generated the largest retraction force (P < .001). The largest vertical forces on the unit were generated using skeletal anchorage, followed by skeletal anchorage with power arms, and finally dental anchorage. Power arms were found to generate larger intrusive forces on the lateral incisors and extrusive forces on the canines than on other groups. For the posterior anchorage unit, dental anchorage generated the largest protraction and palatal forces. Negligible forces were measured for both skeletal anchorage groups. Vertical forces on the posterior unit were minimal in all cases (<0.1 N). CONCLUSIONS All retraction methods produced sufficient forces to retract the anterior teeth during en masse retraction. Skeletal anchorage reduced forces on the posterior teeth but introduced greater vertical forces on the anterior teeth.
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Alió-Sanz JJ, Claros-Stucchi M, Albaladejo A, Iglesias-Conde C, Alvarado-Lorenzo A. In vitro comparative study on the friction of stainless steel wires with and without Orthospeed® (JAL 90458) on an inclined plane. J Clin Exp Dent 2016; 8:e141-5. [PMID: 27034753 PMCID: PMC4808308 DOI: 10.4317/jced.52715] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/17/2015] [Indexed: 11/25/2022] Open
Abstract
Background During the treatment of orthodontics, in the mechanics of slide, there takes place friction, which they reduce the slide of the arch across bracket. Therefore, clinical there takes place an increase of the time of treatment. There are different the technologies that try to reduce this friction, as the self-ligating braces.
The purpose of this study was to research the in vitro behavior of JAL 90458 as a buffering agent which reduces friction between brackets and stainless steel arch wires of different cross sections and sizes. Material and Methods Three types of stainless steel wires with different cross sections and three types of ligatures were used with and without JAL 90458 to measure the friction according to the time and distance traveled by the brackets on an inclined plane with two angulations. The Kruskal-Wallis one-way analysis of variance by ranks was applied to determine the degree of friction between the group using and the group not using the product (P ≤ .05). Results Separate analysis of the arch wires, ligatures and angulation with and without the compound revealed statistically significant differences between the groups, showing that friction was reduced significantly when JAL 90458 was used (P ≤ .01). The 0.021x0.025” arch wires and the arch wires attached using elastic ligatures produce the least resistance to sliding among all of those analyzed when the product was not used (P ≤ .05). Conclusions The results show that JAL 90458 reduces friction independently of arch wire cross section, type of ligature and angulation of the measuring instrument. Key words:Friction, JAL 90458, arch wires, ligatures, in vitro.
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Affiliation(s)
- Juan J Alió-Sanz
- Professor and Chair, Department of Orthodontics, Complutense University of Madrid, Madrid, Spain
| | - Miguel Claros-Stucchi
- Master's in Dental Science, Department of Orthodontics, Complutense University of Madrid, Madrid, Spain
| | - Alberto Albaladejo
- Professor in Orthodontics, School of Dentistry, Department of Surgery, University of Salamanca, Madrid, Spain
| | | | - Alfonso Alvarado-Lorenzo
- Professor in Orthodontics, School of Dentistry, Department of Surgery, University of Salamanca, Madrid, Spain
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21
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Tominaga JY, Ozaki H, Chiang PC, Sumi M, Tanaka M, Koga Y, Bourauel C, Yoshida N. Effect of bracket slot and archwire dimensions on anterior tooth movement during space closure in sliding mechanics: A 3-dimensional finite element study. Am J Orthod Dentofacial Orthop 2014; 146:166-74. [DOI: 10.1016/j.ajodo.2014.04.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 04/01/2014] [Accepted: 04/01/2014] [Indexed: 10/25/2022]
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Moresca R. Class I malocclusion with severe double protrusion treated with first premolars extraction. Dental Press J Orthod 2014; 19:127-38. [PMID: 25162577 PMCID: PMC4296619 DOI: 10.1590/2176-9451.19.3.127-138.bbo] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 04/15/2014] [Indexed: 11/23/2022] Open
Abstract
Angle Class I malocclusion with bymaxillary protrusion is characterized by severe buccal tipping of incisors, which causes upper and lower lip protrusion. First premolars extraction is recommended to reduce facial convexity as a result of anterior teeth retraction, which keeps canines and first molars in key to occlusion. In order to yield orthodontic results that are compatible with ideal esthetic and cephalometric outcomes, the space closure phase needs to be carried out with overbite and incisors torque control. The majority of cases also requires maximum anchorage of posterior teeth. This case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as a requirement for the title of certified by the BBO.
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Affiliation(s)
- Ricardo Moresca
- PhD in Orthodontics, School of Dentistry - University of São Paulo.
MSc in Orthodontics, Methodist University of São Paulo (UMESP). Specialist in
Orthodontics, Federal University of Paraná (UFPR). Adjunct professor, Department of
Orthodontics, Federal University of Paraná (UFPR). Full Professor and Head of the
Postgraduate program in Orthodontics, Positivo University. Certified by the Brazilian
Board of Orthodontics and Facial Orthopedics (BBO)
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23
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Jacob HB, Tadlock L, Swapp A. Skeletal Class III malocclusion correction using miniscrew implants. J World Fed Orthod 2013. [DOI: 10.1016/j.ejwf.2013.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kojima Y, Kawamura J, Fukui H. Finite element analysis of the effect of force directions on tooth movement in extraction space closure with miniscrew sliding mechanics. Am J Orthod Dentofacial Orthop 2012; 142:501-8. [PMID: 22999674 DOI: 10.1016/j.ajodo.2012.05.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 05/01/2012] [Accepted: 05/01/2012] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Miniscrews placed in bone have been used as orthodontic anchorage in extraction space closure with sliding mechanics. The movement patterns of the teeth depend on the force directions. To move the teeth in a desired pattern, the appropriate direction of force must be selected. The purpose of this article is to clarify the relationship between force directions and movement patterns. METHODS By using the finite element method, orthodontic movements were simulated based on the remodeling law of the alveolar bone. The power arm length and the miniscrew position were varied to change the force directions. RESULTS When the power arm was lengthened, rotation of the entire maxillary dentition decreased. The posterior teeth were effective for preventing rotation of the anterior teeth through an archwire. In cases of a high position of a miniscrew, bodily tooth movement was almost achieved. The vertical component of the force produced intrusion or extrusion of the entire dentition. CONCLUSIONS Within the limits of the method, the mechanical simulations demonstrated the effect of force direction on movement patterns.
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Affiliation(s)
- Yukio Kojima
- Department of Mechanical Engineering, Nagoya Institute of Technology, Japan.
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25
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Tominaga JY, Chiang PC, Ozaki H, Tanaka M, Koga Y, Bourauel C, Yoshida N. Effect of play between bracket and archwire on anterior tooth movement in sliding mechanics: A three-dimensional finite element study. JOURNAL OF DENTAL BIOMECHANICS 2012; 3:1758736012461269. [PMID: 23115578 PMCID: PMC3480707 DOI: 10.1177/1758736012461269] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The aim of this study was to clarify the effect of the play between the bracket and the archwire on anterior tooth movement subjected to the retraction force from various lengths of power arms in sliding mechanics. MATERIALS AND METHODS A three-dimensional finite element method was used to simulate en masse anterior tooth retraction in sliding mechanics. The displacements of the maxillary incisor and the archwire deformation were calculated when the retraction force was applied. RESULTS When a play did not exist, bodily movement was obtained at 5.0 mm length of power arm. In case a play existed, bodily movement was observed at the power arm length of 11.0 mm. CONCLUSIONS In the actual clinical situation, a bracket/archwire play and the torsion of the archwire within the bracket slot should be taken into consideration to prescribe an optimal power arm length and to achieve effective anterior tooth movement.
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Affiliation(s)
- Jun-Ya Tominaga
- Department of Orthodontics and Dentofacial Orthopedics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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