1
|
Tarkan H, Guvenc IS. Finite element analysis of the effects of different archwire forms and power arm positions on maxillary incisors in en masse retraction using fixed lingual orthodontic appliances. Korean J Orthod 2024; 54:265-273. [PMID: 39049466 PMCID: PMC11422679 DOI: 10.4041/kjod23.196] [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: 10/04/2023] [Revised: 02/15/2024] [Accepted: 04/12/2024] [Indexed: 07/27/2024] Open
Abstract
Objective This study aimed to investigate the effects of archwire form and power arm positions on maxillary incisors during lingual en masse retraction supported by miniscrew implants, using the finite element analysis method. Methods Sliding mechanics for lingual en masse retraction were simulated using the finite element method. Power arms were placed mesial and distal to the maxillary canine with straight and mushroom-shaped archwires. Miniscrews provided absolute anchorage for retraction force. Results When power arms were positioned mesial to the canine teeth, an increase in the intercanine distance was observed, while a decrease was noted when the power arms were distal to the canine tooth. Lateral incisors exhibited a greater torque loss, particularly when the power arm was mesial to the canine tooth. In the central incisors, the mushroom archwire resulted in intrusion, while the straight archwire showed an extrusion tendency. Movements in groups using the straight archwire were less controlled compared to those in groups using the mushroom archwire. Conclusions The archwire form and the position of the power arm affected the torque loss and vertical position of incisors during lingual en masse retraction supported by miniscrew implants. The most controlled movement was achieved with the combination of a power arm positioned distal to the canine tooth and a mushroom archform.
Collapse
Affiliation(s)
- Hilal Tarkan
- Department of Orthodontics, Usak University, Usak, Türkiye
| | | |
Collapse
|
2
|
Attia AM, Shibl LA, Dehis HM, Mostafa YA, El-beialy AR. Evaluation of anchorage loss after en masse retraction in orthodontic patients with maxillary protrusion using friction vs frictionless mechanics: randomized clinical trial. Angle Orthod 2024; 94:532-540. [PMID: 39230024 PMCID: PMC11363983 DOI: 10.2319/113023-791.1] [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: 11/01/2023] [Accepted: 04/01/2024] [Indexed: 09/05/2024] Open
Abstract
OBJECTIVES To evaluate anchorage loss after en masse retraction in bimaxillary dentoalveolar protrusion patients using friction vs frictionless mechanics. MATERIALS AND METHODS Thirty patients with bimaxillary dentoalveolar protrusion needing extraction of upper first premolars and en masse retraction with maximum anchorage were included in this two-arm, parallel, single-center, single-blinded randomized clinical trial with a 1:1 allocation ratio using fully sealed opaque envelopes. Friction group retraction utilized elastomeric power chain between miniscrews and hooks crimped mesial to upper canines on 17 × 25 stainless steel archwire. Frictionless group used customized T-loop springs loading upper first molars indirectly anchored to miniscrews. Activation was every 4 weeks until full retraction. The primary outcome assessed was anchorage loss evaluated at cusp tip and root apex of the first molar. First molar rotation, incisor tip and torque, and root resorption of anterior teeth were evaluated on digital models and cone beam computed tomography taken before and after space closure. RESULTS Anchorage loss at crown of first molar was significantly more in frictionless group by 2.1 mm (95% CI = -0.4 to 3.5), (P = .014), while there was no significant difference in anchorage loss at root apex between groups. Significant mesial in molar rotation of 6.672° (95% CI = 12.2-21.2), (P = 0.02) was greater in the frictionless group. Both groups showed comparable tip, torque, and root resorption values. No severe harms were reported. There was mild gingival overgrowth and inflammation in the frictionless group due to T-loop irritation. CONCLUSIONS Extra anchorage considerations are needed during en masse retraction when frictionless mechanics is implemented as higher anchorage loss and molar rotation were detected. No difference in tip, torque, and root resorption was observed.
Collapse
Affiliation(s)
- Amr Mahmoud Attia
- Corresponding author: Dr Amr R El-Beialy, 11 ElSaraya Street, Manial, Cairo, Egypt (e-mail: )
| | | | | | | | | |
Collapse
|
3
|
Zheng B, Ran J, He J, Al-Yafrusee ESAM, Zhao Y, Liu Y. Three-dimensional finite element analysis of the uprighting movement of mandibular mesially inclined second molars. Am J Orthod Dentofacial Orthop 2024; 165:314-320. [PMID: 37921729 DOI: 10.1016/j.ajodo.2023.09.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 09/01/2023] [Accepted: 09/01/2023] [Indexed: 11/04/2023]
Abstract
INTRODUCTION The mesially inclined mandibular second molar can be supported upright by the microimplant anchorage. This study established the finite element model to analyze the displacement trend and periodontal ligament (PDL) stress distribution of the uprighting mandibular second molar with the microimplant under different conditions. METHODS A 3-dimensional model of the mandible and dentition was established. The mesial inclination of the mandibular second molar was 30°, 45°, and 60°. Microimplants were implanted between the buccal side of the second premolar and the first molar and in the distal part of the mandibular second molar, respectively. Six groups were set, each loaded with 0.5 N of force. The second molar initial displacement trend and PDL stress distribution were evaluated. RESULTS The PDL stress of mandibular second molars in all groups was within the physiological limit, and the PDL stress of mandibular second molars in the distal implant groups was lower than that of mandibular second molars in the mesial implant groups. PDL stress concentration in the cervical area. Tooth displacement decreased as the mesial inclination angle of the second molars increased. The sagittal displacement of mesial implant groups was larger, and there was a tendency of mesiobuccal torsion when standing uprighting; the vertical displacement of distal implant groups was larger, and there was a tendency of distal lingual torsion when standing uprighting. CONCLUSIONS Distal microimplant has a better extrusion effect on the mesially inclined second molar, whereas mesial microimplant has a better effect on the distal movement. The optimal orthodontic force for microimplant traction on mesially inclined second molars is 0.5-0.8 N.
Collapse
Affiliation(s)
- Bowen Zheng
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China
| | - Junyi Ran
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China
| | - Jia He
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China
| | - Enas Senan Ali Mohammed Al-Yafrusee
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China
| | - Yang Zhao
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China
| | - Yi Liu
- Department of Orthodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, Liaoning, China.
| |
Collapse
|
4
|
Alhasyimi AA, Ayub A, Farmasyanti CA. Effectiveness of the Attachment Design and Thickness of Clear Aligners during Orthodontic Anterior Retraction: Finite Element Analysis. Eur J Dent 2024; 18:174-181. [PMID: 36963425 PMCID: PMC10959602 DOI: 10.1055/s-0043-1761452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
OBJECTIVE Clear aligner treatment (CAT) provides orthodontic patients with a comfortable treatment alternative; however, this device has limited capacity to facilitate tooth movements. Although composite attachment has been proposed to facilitate tooth displacement, some of its aspects, such as aligner thickness, can influence CAT's precision. This work aimed to compare the stress distribution patterns produced by clear aligners with different thicknesses and composite attachment shapes during anterior retraction. MATERIALS AND METHODS Maxillary models consisting of clear aligners, maxillary teeth, and various attachments to the upper central incisor's labial surface were generated. Three models were built to mimic the retraction of the upper central incisors. Each had a distinct attachment design (rectangular attachment, ellipsoid attachment, and pyramidal attachment) and various aligner thicknesses (0.75, 0.85, 0.95, 1.05, and 1.15 mm). Upper central incisor retraction was accomplished using clear aligners. Finite element analysis was used to examine the built models. Stress distribution pattern was examined. RESULTS The greater the thickness of the aligner, the higher the stress experienced by the teeth. The 0.75 mm-thick aligner induces the lightest stress with a minimum of 0.0037623 MPa and a maximum of 0.32859 MPa. Meanwhile, the 1.5 mm-thick aligner has the highest stress with a minimum of 0.004679 MPa and a maximum of 0.43858 MPa. The force distribution on rectangular attachments appears evenly distributed. The maximum pressure force on rectangular attachments has a minimum of 0.38828 MPa, which is smaller than the maximum on ellipsoid and pyramidal attachments at 0.40933 and 0.45099 MPa, respectively. CONCLUSION The best aligner thickness is 0.75 to 0.85 mm for anterior retraction. An aligner with 0.95 mm thickness can still be used when a remarkable amount of tooth movement force is needed; however, this exception is only applicable to a limited number of clear aligner trays. The ellipsoid attachment is the best type of attachment because the resulting force is substantial and evenly distributed.
Collapse
Affiliation(s)
- Ananto Ali Alhasyimi
- Department of Orthodontics, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Aulia Ayub
- Department of Orthodontics, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | | |
Collapse
|
5
|
Zalaquett R, Karam R, Kaddah F, Khoury E, El Khoury T, Ghoubril J, Kassis A. Effect of power arm length combined with additional anterior torque on the axial orientation of the maxillary incisors during en-masse retraction: A finite element analysis. Am J Orthod Dentofacial Orthop 2024; 165:220-231. [PMID: 37906243 DOI: 10.1016/j.ajodo.2023.08.016] [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: 02/01/2023] [Revised: 08/01/2023] [Accepted: 08/01/2023] [Indexed: 11/02/2023]
Abstract
INTRODUCTION This study aimed to clarify the effect of power arm length combined with additional torque incorporated into the archwire on the controlled movement of the anterior teeth using the finite element method. METHODS An adult patient requiring medium anchorage after extraction of the maxillary first premolars was selected for this study. The power arms were placed between the lateral incisor and the canine at 3 levels: 3 mm, 6 mm, and 9 mm. A 150 g of retraction force was applied from each height of the anterior hook to the first molar tube, with 0°, 5°, and 10° of applied lingual root torque on the incisors. RESULTS A 3-mm hook with 10° of applied torque, a 6-mm hook with 5° of applied torque, or a 9-mm hook with no extra torque constituted the best combinations targeted at controlling the inclination of incisors during retraction. Extrusion and distal tipping of the canine were observed. Moreover, mesial tipping and mesiopalatal rotation of the molar were unavoidable. Finally, intercanine and intermolar widths were decreased. CONCLUSIONS Adding extra torque on the incisors or using high torque brackets is recommended for patients with maxillary first premolar extraction.
Collapse
Affiliation(s)
- Rime Zalaquett
- Department of Orthodontics, School of Dental Medicine, Saint Joseph University, Beirut, Lebanon
| | - Richard Karam
- Lebanese Center for Studies and Research of Construction, Faculty of Engineering, Saint Joseph University, Beirut, Lebanon
| | - Fouad Kaddah
- Lebanese Center for Studies and Research of Construction, Faculty of Engineering, Saint Joseph University, Beirut, Lebanon
| | - Elie Khoury
- Department of Orthodontics, School of Dental Medicine, Saint Joseph University, Beirut, Lebanon
| | - Tony El Khoury
- Department of Orthodontics, School of Dental Medicine, Saint Joseph University, Beirut, Lebanon
| | - Joseph Ghoubril
- Department of Orthodontics, School of Dental Medicine, Saint Joseph University, Beirut, Lebanon.
| | - Adib Kassis
- Department of Orthodontics, School of Dental Medicine, Saint Joseph University, Beirut, Lebanon
| |
Collapse
|
6
|
Pareek PK, Kumar A, Bhariya BS, Bamal R, Yadav L, Jaswal A. Influence of the Curve of Spee on Tooth Displacement Patterns: A Finite Element Analysis at Varying Implant Heights. Cureus 2024; 16:e54283. [PMID: 38496186 PMCID: PMC10944568 DOI: 10.7759/cureus.54283] [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: 02/13/2024] [Indexed: 03/19/2024] Open
Abstract
Background Monocortical mini-screw-type temporary anchorage devices (TADs), or mini-screws, have significantly impacted orthodontic treatment strategies, especially in severe crowding and protrusion cases. These devices offer flexibility in placement sites, but the chosen location can considerably influence tooth displacement patterns. Key factors include the 'line of force' and the biomechanical properties of orthodontic tools. By analyzing tension distribution and three-dimensional displacements, the finite element method (FEM) provides a thorough means to comprehend these patterns. The Curve of Spee (COS) is a crucial factor potentially affecting displacement. Objective This study aimed to leverage finite element analysis (FEA) to understand the impact of varying mini-implant heights (10 mm, 13 mm, and 16 mm) on the displacements of different tooth types under a consistent force of 150 gm and compare these displacements both in the presence and absence of the COS. Materials and methods A CAD model of the jaw and teeth was developed using CT scan data and a Rexcan III 3D White Light Scanner. This model was meshed in Altair HyperMesh using tetrahedral elements, resulting in a Finite Element Model. The model incorporated various components, including teeth, the periodontal ligament (PDL), alveolar bone, brackets, a titanium mini-screw, and an archwire measuring 0.019 x 0.025 inches. Unique material properties were assigned to the PDL, and the assembly accurately replicated the clinical alignment of the archwire and brackets. Subsequently, stress and strain analyses were conducted on the model using the FEM. Results The displacement patterns of various teeth at implant heights of 10 mm, 13 mm, and 16 mm under a 150-gm force were analyzed in relation to the COS. Notably, for the central incisor, the COS significantly affected displacements in the Y and Z directions. Similarly, the Lateral Incisor and Canine exhibited marked changes in the Z direction with the presence of the COS. The Second Premolar's apex displacement showed significant variation due to the COS, while the First Molar displayed notable changes in the X direction. Generally, the presence of the COS either maintained or slightly increased Z-directional displacements across teeth, particularly at the apices. Conclusion The presence of COS significantly influences tooth displacement patterns when using mini-screws at different implant heights. Central incisors, lateral incisors, and canines are particularly sensitive to changes in the Z direction with the COS. The biomechanical analysis emphasizes the importance of considering COS in treatment planning for optimal results with mini-implants in orthodontics.
Collapse
Affiliation(s)
- Pankaj K Pareek
- Department of Orthodontics, Rajasthan Dental College and Hospital, Jaipur, IND
| | - Ashish Kumar
- Department of Orthodontics, Rajasthan Dental College and Hospital, Jaipur, IND
| | | | - Renuka Bamal
- Department of Orthodontics, NIMS Dental College and Hospital, Jaipur, IND
| | - Lucky Yadav
- Department of Dental and Oral Surgery, Lady Hardinge Medical College, Delhi, IND
| | | |
Collapse
|
7
|
Ji L, Li B, Wu X. Evaluation of biomechanics using different traction devices in distalization of maxillary molar with clear aligners: a finite element study. Comput Methods Biomech Biomed Engin 2023; 26:559-567. [PMID: 35543236 DOI: 10.1080/10255842.2022.2073789] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The study aimed to mechanically evaluate the tooth displacement of molar distalization by clear aligners combined with micro-implant through different traction devices using finite element analysis. A three-dimensional finite element model of complete maxillary dentition was constructed. Simultaneously move the maxillary first and second molars 0.2 mm distally at the height of 4 mm and 6 mm of micro-implant, and 150 g force was applied to button, precision cut and angelbutton respectively. Initial tooth movement in six different conditions of anterior tooth and molars was analyzed and calculated with ANSYS software. All the upper anterior tooth exhibited uncontrolled labial tipping and intrusion upon the six conditions, and the central incisor showed the largest tendency of crown labial inclination. Among the absolute values of crown-root displacement difference of the anterior tooth in sagittal direction, the angelbutton was the smallest, which means the torque control ability was superior to others. However, button played a more accurate role in the sagittal and vertical control of canine. With the increase of micro-implant height, the torque control ability of anterior tooth was decreased, but the intrusion trend increased. The controlled distal inclination with extrusion of the first molar and uncontrolled distal inclination with intrusion of the second molar were observed, and the angelbutton had more effective horizontal and vertical control on molars, which was close to bodily movement than others. As a new type of traction device, angelbutton has excellent anchorage control effect in clear aligners therapy of molar distalization, which further realizes the accurate expression of orthodontic force.
Collapse
Affiliation(s)
- Lili Ji
- Dental Hospital of Shanxi Medical University, Taiyuan, P. R. China
| | - Bing Li
- Dental Hospital of Shanxi Medical University, Taiyuan, P. R. China
| | - Xiuping Wu
- Dental Hospital of Shanxi Medical University, Taiyuan, P. R. China
| |
Collapse
|
8
|
Wang Y, Chen J, Qin S, Han X, Liao L, Sima X, Guo W. An in vivo evaluation of clear aligners for optimal orthodontic force and movement to determine high-efficacy and periodontal-friendly aligner staging. Heliyon 2023; 9:e15317. [PMID: 37113787 PMCID: PMC10126945 DOI: 10.1016/j.heliyon.2023.e15317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 03/15/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
Objectives To investigate the effect of aligner displacement on tooth movement and periodontal health to improve the efficiency of aligner treatment and explore the mechanism in vivo. Methods A two-tooth site was established by a finite element (FE) model to virtually evaluate aligner staging. A randomized controlled experiment was conducted when the tooth sites in beagles were treated with fixed or aligner appliances with different movement and force, and tooth movement and internal structure were recorded during the alignment. After sacrificing five dogs, bone-periodontal ligament (PDL)-tooth specimens were removed and processed to conduct uniaxial compression and tensile tests as well as micro-CT imaging and histological analysis. Results Three displacements of 0.25, 0.35 and 0.45 mm were obtained from FE analysis and applied in beagles. In general, aligners had poorer performance on movement compared to fixed systems in vivo, but the aligner with a staging of 0.35 mm had the highest accuracy (67.46%) (P < 0.01). Loaded with severe force, fixed sites exhibited tissue damage due to excess force and rapid movement, while aligners showed better safety. The PDL under a 0.35-mm aligner treatment had the highest elastic modulus in the biomechanical test (551.4275 and 1298.305 kPa) (P < 0.05). Conclusions Compared to fixed appliances, aligners achieve slightly slower movement but better periodontal condition. Aligners with an interval of 0.35 mm have the highest accuracy and best PDL biomechanical and biological capacities, achieving the most effective and safest movement. Even with complexity of oral cavity and lack of evaluation of other factors, these results provide insight into faster displacement as a method to improve the efficacy of aligners.
Collapse
Affiliation(s)
- Yuru Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School/Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jie Chen
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School/Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Siwen Qin
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School/Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xue Han
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School/Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lijun Liao
- Sichuan Hospital of Stomatology, Chengdu, China
| | - Xiutian Sima
- Department of Neurosurgery, West China School of Medicine/West China Hospital, Sichuan University, Chengdu, China
- Corresponding author. Department of Neurosurgery, West China Hospital, Sichuan University, 37# Wainan Guoxue Road, Chengdu 610041, China.
| | - Weihua Guo
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China School/Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- Corresponding author. Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, No. 14, 3rd Sec., Ren Min Nan Road, Chengdu 610041, China.
| |
Collapse
|
9
|
Zhang L, Guo R, Xu B, Wang Y, Li W. Three-dimensional evaluation of maxillary tooth movement in extraction patients with three different miniscrew anchorage systems: a randomized controlled trial. Prog Orthod 2022; 23:46. [PMID: 36529797 PMCID: PMC9760583 DOI: 10.1186/s40510-022-00441-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 10/10/2022] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE To compare the three-dimensional (3-D) movement of maxillary teeth in response to three common miniscrew anchorage systems in extraction patients with maxillary dentoalveolar protrusion. MATERIALS AND METHODS The study employed a randomized controlled single-blinded design with three arms. Thirty extraction patients who required maximum anchorage to retract maxillary anterior teeth were included and randomly allocated into three treatment groups: space closure with direct miniscrew anchorage and low crimpable hooks (DL group), indirect miniscrew anchorage and low crimpable hooks (IL group), and direct miniscrew anchorage and high crimpable hooks (DH group). Cone beam computed tomography (CBCT) images of all included patients were obtained immediately before (T0) and after (T1) space closure. The outcomes were 3-D positional changes of maxillary central incisor, lateral incisor, canine, second premolar, and first molar. The repeated measures analysis of variance with post hoc LSD test was used to evaluate differences among groups. RESULTS A significant intrusion (- 1.34 mm; 95% CI, - 1.60 mm, 1.08 mm) and buccal (- 6.92°; 95% CI, - 8.67°, - 5.13°) and distal (4.90°; 95% CI, 3.75°, 6.04°) inclination of the maxillary first molars were observed in the DL group, compared to the other two groups. The mesial movement (- 0.40 mm; 95% CI, - 0.83 mm, - 0.03 mm) of the maxillary first molars was found in the IL group, while the DL (0.44 mm; 95% CI, 0.15 mm, 0.73 mm) and IL (0.62 mm; 95% CI, 0.28 mm, 0.96 mm) groups exhibited distal movement. In the DH group, the lingual inclination changes of maxillary central incisor (5.04°; 95% CI, 2.82°, 7.26°) were significantly lower, which is indicative of good lingual root torque control of the maxillary anterior teeth. CONCLUSION Three miniscrew anchorage systems produced significantly different 3-D maxillary tooth movement. The maxillary first molars were significantly buccally and distally inclined and intruded in patients using direct miniscrew anchorages with low crimpable hooks. Direct miniscrew anchorages with high crimpable hooks could help to achieve better lingual root torque control of the maxillary incisors. Trial registration The trial was registered at www.chictr.org.cn (ChiCTR1900026960). Registered 27 October 2019.
Collapse
Affiliation(s)
- Liwen Zhang
- grid.415954.80000 0004 1771 3349Department of Dental Medical Center, China-Japan Friendship Hospital, Beijing, People’s Republic of China
| | - Runzhi Guo
- grid.11135.370000 0001 2256 9319Department of Orthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing, 100081 People’s Republic of China
| | - Baohua Xu
- grid.415954.80000 0004 1771 3349Department of Dental Medical Center, China-Japan Friendship Hospital, Beijing, People’s Republic of China
| | - Yue Wang
- grid.415954.80000 0004 1771 3349Department of Dental Medical Center, China-Japan Friendship Hospital, Beijing, People’s Republic of China
| | - Weiran Li
- grid.11135.370000 0001 2256 9319Department of Orthodontics, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing, 100081 People’s Republic of China
| |
Collapse
|
10
|
Zhang C, Ji L, Liao W, Zhao Z. A novel biomechanical system to intrude the upper incisors and control overbite: Posterior miniscrew-assisted lever arm and 2 cases report. Medicine (Baltimore) 2022; 101:e31616. [PMID: 36451401 PMCID: PMC9704898 DOI: 10.1097/md.0000000000031616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
RATIONALE Overbite control is a key factor in orthodontic treatment. In some cases, incisor intrusion is essential and could be an optimal strategy for overbite control. The aim of this article was to introduce a biomechanical system called the posterior miniscrew-assisted lever arm, which is innovative in using existing posterior miniscrews to intrude the upper incisors and to control anterior overbite while simultaneously retracting the anterior teeth. Its efficiency in incisor intrusion has been proved with 2 cases. PATIENT CONCERNS Two adult women who came for orthodontic treatment with the chief complaint of convex profile were included in this study. DIAGNOSIS Both patients had similar malocclusions of Class II molar relationship, anterior deep overjet, and anterior deep overbite. INTERVENTIONS Their treatment plans were to extract 4 first premolars and insert 2 maxillary posterior buccal miniscrews. After teeth aligning and leveling, en masse retraction was started in both arches. During the space-closing stage, posterior miniscrew-assisted lever arms were placed in their upper arches so as to intrude upper incisors and control the overbite. OUTCOMES After respectively 4 months and 3 months of incisor intrusion, the anterior overbite was successfully reduced to the normal range in each patient. Cephalometric analysis and superimposition also confirmed the treatment effect of this biomechanical system on incisor intrusion. LESSONS The posterior miniscrew-assisted lever arm is a valuable biomechanical system for intruding incisors and controlling anterior overbite.
Collapse
Affiliation(s)
- Chenghao Zhang
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
| | - Ling Ji
- West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
| | - Wen Liao
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
| | - Zhihe Zhao
- Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
- * Correspondence: Zhihe Zhao, Department of Orthodontics, West China Hospital of Stomatology, State Key Laboratory of Oral Diseases& National Clinical Research Center for Oral Diseases, Sichuan University, 3rd section of Renmin South Road, Chengdu 610041, Sichuan Province, China (e-mail: )
| |
Collapse
|
11
|
Xia Q, He Y, Jia L, Wang C, Wang W, Wang C, Song J, Fan Y. Assessment of labially impacted canines traction mode with clear aligners vs. fixed appliance: A comparative study based on 3D finite element analysis. Front Bioeng Biotechnol 2022; 10:1004223. [PMID: 36277381 PMCID: PMC9579379 DOI: 10.3389/fbioe.2022.1004223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/21/2022] [Indexed: 12/05/2022] Open
Abstract
Purpose: The objective of this study was to evaluate and compare the biomechanical differences between clear aligner and fixed appliance in the traction of labially impacted canines based on 3D finite element analysis. Methods: A series of patient-oriented finite element models were constructed, including a maxillary dentition with a right labially canine, maxilla, periodontal ligaments, traction attachments, and clear aligners. The two most common clinical scenarios were investigated: Scenario A: impacted canine (distal) and Scenario B: impacted canine (mesial). For each clinical scenario, three traction models with clear aligners and one fixed appliance model were established. Results: In all four models, the impacted canines exhibited similar initial displacement tendencies of mesially rotated in Scenario A and distally rotated in Scenario B, and with small differences in periodontal ligament stress magnitude. However, the sum of the periodontal ligament stresses of the anchorage teeth in the clear aligner mode was in the range of 56.28–76.21 kPa and in the fixed appliance mode was in the range of 6.61–7.22 kPa. The maximum value of initial displacement of the anchorage teeth in the clear aligner mode was in the range of 13.71–19.72 μm, while in the fixed appliance mode was 3.10–3.92 μm. Conclusion: For impacted canines, clear aligner mode and fixed appliance mode have little difference in biomechanical effect. However, the anchorage teeth in the clear aligner mode endure higher stress and show a more pronounced displacement tendency. In addition, the biomechanical effects of different clear aligner traction models are various but not obvious.
Collapse
Affiliation(s)
- Qian Xia
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Yao He
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Lurong Jia
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Chunjuan Wang
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Weixu Wang
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Chao Wang
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
- *Correspondence: Jinlin Song, ; Chao Wang,
| | - Jinlin Song
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
- *Correspondence: Jinlin Song, ; Chao Wang,
| | - Yubo Fan
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, School of Engineering Medicine, Beihang University, Beijing, China
| |
Collapse
|
12
|
He X, Zhuang WH, Zhang DL. A Three-Dimensional Finite Element Analysis: Maxillary Dentition Distalization with the Aid of Microimplant in Lingual Orthodontics. Int J Gen Med 2021; 14:8455-8461. [PMID: 34824544 PMCID: PMC8609240 DOI: 10.2147/ijgm.s337212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/28/2021] [Indexed: 12/01/2022] Open
Abstract
Aim To analyze the movement of anterior teeth by changing the height of the power-arm and changing the force application points during whole maxillary dentition distalization with the aid of micro-implants in lingual orthodontics to set a biomechanical reference for effective clinical use of lingual orthodontic appliance. Methods A three-dimensional finite element model of the maxillary teeth with lingual appliance and the associated support tissue was established. Maxillary dentition with the force of 200g was distalized using implant as anchorage, then the movement of anterior teeth was analyzed by changing the length of power-arm (1mm, 3mm, 6mm, 9mm) and by changing the force location from lingual side to buccal side. Results During whole maxillary dentition distalization with aid of the implants in lingual orthodontics: when the height of power arm was 1mm, the anterior teeth rotated clockwise, with the increasing of the height of power-arm, the anterior teeth rotated counterclockwise gradually. When the height of power-arm was 9mm, all anterior teeth rotated counterclockwise. Central incisor and lateral incisor rotated counterclockwise and canine rotated clockwise when the buccal side force was applied. Conclusion With the increase of the height of the power-arm, the movement pattern of the upper anterior teeth is different. The canine is more sensitive to the height of the power-arm than the central incisor and the lateral incisor. When the height of the power-arm reaches 9mm, the upper anterior teeth are displayed as crown tipping buccally movement. Compare with lingual side force, the buccal side force do better in preventing the loss of anterior tooth torque. If the upper anterior teeth are up-right or lingually tipped before treatment, it is preferable to use longer power-arm or buccal side traction force. If the anterior teeth are already tipped buccally, then short power-arm or lingual side force is advised.
Collapse
Affiliation(s)
- Xin He
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, 100050, People's Republic of China
| | - Wei-Hang Zhuang
- Department of Stomatology, Beijing Rytime Dental Hospital, Beijing, 100024, People's Republic of China
| | - Dong-Liang Zhang
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, 100050, People's Republic of China
| |
Collapse
|
13
|
Akbari A, Wang D, Chen J. Peak loads on teeth from a generic mouthpiece of a vibration device for accelerating tooth movement. Am J Orthod Dentofacial Orthop 2021; 162:229-237. [PMID: 34420844 DOI: 10.1016/j.ajodo.2021.04.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 01/16/2023]
Abstract
INTRODUCTION The effect of vibrational force (VF) on accelerating orthodontic tooth movement depends on the ability to control the level of stimulation in terms of its peak load (PL) on the tooth. The objective of this study was to investigate the PL distribution on the teeth when a commercial VF device is used. METHODS Finite element models of a human dentition from cone-beam computed tomography images of an anonymous subject and a commonly used commercial VF device were created. The device consists of a mouthpiece and a VF source. The maxilla and mandible bites on the mouthpiece with the VF applied to it. Interface elements were used between the teeth and the mouthpiece, allowing relative motion at the interfaces. The finite element model was validated experimentally. Static load and VF with 2 frequencies were used, and the PL distributions were calculated. The effects of mouthpiece materials and orthodontic appliances on the PL distribution were also investigated. RESULTS The PL distribution of this kind of analyzed device is uneven under either static force or VF. Between the anterior and posterior segments, the anterior segment receives the most stimulations. The mouthpiece material affects the PL distribution. The appliance makes the PL more concentrated on the incisors. The VF frequencies tested have a negligible influence on both PL magnitude and distribution. CONCLUSIONS The device analyzed delivers different levels of stimulation to the teeth in both maxilla and mandible. Changing the material property of the mouthpiece alters the PL distribution.
Collapse
Affiliation(s)
- Amin Akbari
- Department of Mechanical and Energy Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Ind
| | - Dongcai Wang
- Department of Mechanical and Energy Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Ind; College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Jie Chen
- Department of Mechanical and Energy Engineering, and Department of Orthodontics and Oral Facial Genetics, Indiana University Purdue University Indianapolis, Indianapolis, Ind.
| |
Collapse
|
14
|
Al-Thomali Y, Basha S, Mohamed RN. Effect of surface treatment on the mechanical stability of orthodontic miniscrews. Angle Orthod 2021; 92:127-136. [PMID: 34338745 DOI: 10.2319/020721-111.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/01/2021] [Indexed: 12/09/2022] Open
Abstract
OBJECTIVES To provide collective quantitative evidence about the effect of surface treatments on the mechanical stability of orthodontic miniscrews (MSs). MATERIALS AND METHODS The study was registered in PROSPERO (No. CRD42020209652). The research question was defined according to the PICO (population, intervention, control, and outcomes) format. Various research databases were searched for animal and human studies on effects of surface treatment on the mechanical stability of MSs. Both prospective and retrospective in vivo clinical studies published in English were included. The risk of bias was assessed using SYRCLE's risk of bias tool for animal studies. The meta-analysis was conducted using RevMan 5.4. RESULTS A total of 109 articles were identified; 14 were included in the systematic review, and seven studies with sandblasting, acid etching (SLA) methods of surface treatment were included for meta-analysis. The number of study participants ranged from 6 to 24 (total n = 185), with a mean of 13.2. A total of 949 MSs were used with a mean of 67.8. The overall success rate for surface-treated MSs ranged from 47.9% to 100%. Forest plot of removal torque values showed significantly higher values for SLA surface-treated MSs compared with controls with a standard mean difference of 2.61 (95% confidence interval = 1.49-3.72, I2 = 85%). Forest plot of insertion torque showed a standard mean difference of -6.19 (95% confidence interval = -13.63-1.25, I2 = 98%, P = .10). CONCLUSIONS Surface treatment of MSs improved primary and secondary stability with good osseointegration at the bone-implant surface. However, significant heterogeneity across the studies included in the meta-analysis made it difficult to draw conclusions.
Collapse
|
15
|
Khan J, Goyal M, Kumar M, Kushwah A, Kaur A, Sharma M. Comparative evaluation of displacement and stress distribution pattern during maxillary arch distalization with Infra Zygomatic Screw- A three dimensional finite element study. Int Orthod 2021; 19:291-300. [PMID: 33875363 DOI: 10.1016/j.ortho.2021.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/19/2021] [Accepted: 03/20/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVE This study aimed to evaluate and compare the distribution of stress and displacement of teeth during maxillary arch distalization with IZC (Infra zygomatic crest) screw with two maxillary positions and different lever arm heights. SETTINGS AND DESIGN Six three-dimensional finite element models of the maxillary arch were constructed with third molars extracted. Models 1, 2 and 3: IZC 6 (mesial to mesiobuccal root of first molar, 6) with 0mm, 4mm and 8mm lever arm height; Models 4, 5 and 6: IZC 7 (mesial to mesiobuccal root of second molar, 7) with 0mm, 4mm and 8mm, respectively. MATERIAL AND METHODS MBT preadjusted Brackets (slot size 0.022×0.028") were placed over the clinical crown's centre with 0.019×0.025" stainless steel archwire on all six models. Retraction force of 4N was applied with different combinations of IZC screws and lever arm bilaterally using Nickel-Titanium (NiTi) closed coil spring. Then, evaluation of stress distribution, von Mises stress and maxillary teeth displacement were performed using ANSYS 12.1 software. RESULTS In this study, maximum von Mises stress in alveolar bone (cortical bone) was observed in Model 4 (107.79MPa) at the screw fixation site that was within the optimum limit (135MPa). Different extents of displacements like labiolingual tipping of crown, labiolingual tipping of root, extrusion and intrusion were noticed. The models with 0mm and 4mm lever arm height (models1, 2, 4 and 5) showed more controlled crown and root movements in comparison to 8mm long lever arm models (models 3 and 6). In model 5, a maximum distal movement compared to all other five models was observed. CONCLUSIONS IZC 7 position showed the most favourable results (maximum distalization) with the lever arm height of 4mm. Therefore, the nearer the force to the centre of resistance of the tooth, the greater is distalization. Stresses on the IZC screw decreases when lever arm height increases, in all the models.
Collapse
Affiliation(s)
- Junaid Khan
- Department of Orthodontics and Dentofacial Orthopaedics, Teerthanker Mahaveer Dental College, Moradabad, Uttar Pradesh, India.
| | - Manish Goyal
- Department of Orthodontics and Dentofacial Orthopaedics, Teerthanker Mahaveer Dental College, Moradabad, Uttar Pradesh, India
| | - Mukesh Kumar
- Department of Orthodontics and Dentofacial Orthopaedics, Teerthanker Mahaveer Dental College, Moradabad, Uttar Pradesh, India
| | - Ashish Kushwah
- Department of Orthodontics and Dentofacial Orthopaedics, Institute of Dental Education & Advanced Studies, Gwalior, Madhya Pradesh, India
| | - Amandeep Kaur
- Department of Orthodontics and Dentofacial Orthopaedics, Teerthanker Mahaveer Dental College, Moradabad, Uttar Pradesh, India
| | - Madhur Sharma
- Department of Orthodontics and Dentofacial Orthopaedics, Teerthanker Mahaveer Dental College, Moradabad, Uttar Pradesh, India
| |
Collapse
|
16
|
Agrawal A, Subash P. The Effect of Varied Positioning of Mini-screw, Anterior Retraction Hook, and Resultant Force Vector on Efficient En-Masse Retraction Using Finite Element Method: A Systematic Review. JOURNAL OF INDIAN ORTHODONTIC SOCIETY 2021. [DOI: 10.1177/0301574220982098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Objective: The objective of this systematic review was to assess the available evidence to evaluate the effectiveness of en-masse retraction design with mini-screw with respect to the retraction hook and mini-implant position and height. Methods: The following electronic databases were searched till July 31, 2020: Pro-Quest Dissertation Abstracts and Thesis database Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Google Scholar, US National Library of Medicine, and National Research Register. En-masse retractions with anterior retraction hooks assisted by mini-implant three-dimensional finite element method (3D FEM) models were included in the study. The selected studies were assessed for the risk of bias using the Cochrane Collaboration risk of bias tool. The “traffic plot” and “weighted plot” risk of bias distribution were designed using the ROBVIS tool. The authors extracted and analyzed the data. Results: Twelve studies fulfilled the inclusion criteria. The risks of biases were low for 9 studies and high for 3 studies. Data on mini-implant, retraction hook, and the center of resistance/force vectors were extracted. The outcomes of the included studies were heterogeneous. Conclusions: According to the currently available literature review for successful bodily en-masse tooth movement, the force vector should pass through the center of resistance, which can be achieved by the clinical judgment of placing a mini-screw and an anterior retraction hook. The force from an implant placed at a higher level from the anterior retraction hook will cause intrusion; an implant placed at the medium level shows bodily movement; and an implant placed at a lower level shows tipping forces in consolidated arches.
Collapse
Affiliation(s)
- Ashish Agrawal
- Department of Orthodontics, IMS, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - P Subash
- Department of Orthodontics, IMS, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| |
Collapse
|
17
|
Gonzalez J, Nacy S, Youssef G. Finite element analysis of human skull bone adaptation to mechanical loading. Comput Methods Biomech Biomed Engin 2020; 24:1-12. [PMID: 33241705 DOI: 10.1080/10255842.2020.1850703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/07/2020] [Accepted: 11/10/2020] [Indexed: 01/28/2023]
Abstract
Bones self-optimize their mechanical behavior in response to mechanical stimulus. The objective of this research was to develop an integrated bone remodeling and stress binning algorithms into a finite element environment to elucidate the evolution of the bone properties as a function of loading. The bone remodeling algorithm was used to calculate the change in the density and elastic modulus based on the strain energy stimulus. The stress-binning procedure seeks to assign the properties to each element based on the levels of stress from the previous cycle, eliminating pseudo-lazy-zoning and stress dilation effects. The developed algorithms were used to analyze the response skull to loading associated with orthodontic devices. Specifically, a load was applied between the roots of the canine teeth and the first premolars while constraining the foramen magnum. Full-field contours of the displacement, strain, and strain energy were extracted after each remodeling cycle at nine commonly cephalometric landmarks. The results indicate that the overall mechanical response and the associated properties reached a steady-state behavior after nearly 50 cycles of applying the algorithm, where different zones within the skull exhibited unique evolution based on the locations from the loading and boundary sites. When approaching this steady-state condition, it was found that the upper incisor displacement is reduced by 72%, and the density is reduced by almost 7.5%. The finite element approach can be used in defining the treatment process by dynamically changing the loads. Future research will focus on integrating the time-dependent behavior of the bone.
Collapse
Affiliation(s)
- Jose Gonzalez
- Experimental Mechanics Laboratory, Mechanical Engineering Department, San Diego State University, San Diego, CA, USA
| | - Somer Nacy
- Experimental Mechanics Laboratory, Mechanical Engineering Department, San Diego State University, San Diego, CA, USA
- University of Baghdad, Baghdad, Iraq
| | - George Youssef
- Experimental Mechanics Laboratory, Mechanical Engineering Department, San Diego State University, San Diego, CA, USA
| |
Collapse
|
18
|
Jiang T, Wu RY, Wang JK, Wang HH, Tang GH. Clear aligners for maxillary anterior en masse retraction: a 3D finite element study. Sci Rep 2020; 10:10156. [PMID: 32576935 PMCID: PMC7311544 DOI: 10.1038/s41598-020-67273-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 06/04/2020] [Indexed: 11/23/2022] Open
Abstract
To evaluate tooth behaviours under various maxillary incisor retraction protocols for clear aligner therapy. A three-dimensional finite element model of maxillary dentition was constructed for first premolar extraction. A loading method was developed to mimic the mode of action of clear aligners for incisor en masse retraction. Three protocols with different amounts of retraction and intrusion on incisors were designed. Initial tooth displacements and stresses on periodontal ligaments were analysed with ANSYS software. The central (U1) and lateral (U2) incisors exhibited uncontrolled lingual tipping and extrusion upon 0.25 mm retraction. U1 exhibited translation movement, while U2 underwent less tipping during 0.2 mm retraction and 0.15 mm intrusion. Labial tipping and intrusion of U1 and bodily intrusion of U2 were observed during 0.1 mm of retraction and 0.23 mm of intrusion. With the additional intrusion on incisors, canine showed extrusion movement, and higher stresses on periodontal ligaments were shifted from U2 to canines. Incisors also exhibited different mesial-distal angulation in the three simulations, while posterior teeth all suffered mesial inclination. Incorporating intrusion displacement in clear aligners led to a tendency of lingual root movement during incisor retraction. The complexity of tooth movement should be recognized regarding clear aligner therapy.
Collapse
Affiliation(s)
- Ting Jiang
- Department of Orthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Rui Ying Wu
- Department of Orthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Jian Kai Wang
- Department of Orthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Hong Hong Wang
- Department of Orthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China.,National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, 200011, China
| | - Guo Hua Tang
- Department of Orthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China. .,National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, 200011, China.
| |
Collapse
|
19
|
Qie H, Kong L, Zhang F, Li C, Lu L, Dou C, Shan L. Three-Dimensional Finite Element Analysis on En-Masse Retraction of the Maxillary Anterior Teeth With Quantitative Combined Loading Control. J ORAL IMPLANTOL 2020; 46:214-220. [PMID: 32068860 DOI: 10.1563/aaid-joi-d-19-00340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study aims to elucidate the biomechanical effects of combined loading of maxillary anterior and posterior implants using the sliding method on en-masse retraction of the anterior teeth and to quantify the loading ratio (LR) of anterior and posterior implants to achieve controlled retraction of the maxillary anterior teeth. A three-dimensional finite element model of the maxilla-upper dentition appliance was constructed. Implants were placed on the distal (A) and mesial (B) sides of the lateral incisors as well as on the mesial (C) side of the first molar and different amounts of force were loaded between the implants using 2- or 5-mm traction hooks. The labiolingual movement of the anterior teeth was recorded and the relationship between the LR of the implants and the movement of the central incisors was evaluated. With 2-mm traction hooks, the central incisors exhibited a translation tendency during retraction at lower A/C and B/C LR and labial or lingual crown inclination at higher values. With 5-mm traction hooks, the central incisors, lateral incisors, and canine teeth exhibited a labial crown inclination. The results of this study suggest that 2-mm traction hooks can cause labial crown inclination, translation tendency during retraction, or lingual crown inclination of the central incisors due to alterations in the LR of the anterior and posterior implants. The central incisors only exhibited labial crown inclination during combined loading of the anterior and posterior implants when 5-mm traction hooks were used.
Collapse
Affiliation(s)
- Hui Qie
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Lingliang Kong
- Department of Orthodontics, The Jining Hospital of Stomatology, Jining, China
| | - Fan Zhang
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Chenxi Li
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Lin Lu
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Chenlei Dou
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Lihua Shan
- Department of Orthodontics, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| |
Collapse
|
20
|
THOTE ABHISHEKM, UDDANWADIKER RASHMIV, SHARMA KRISHNA, SHRIVASTAVA SUNITA, REDDY VENKATESWAR. OPTIMUM FORCE SYSTEM FOR EN-MASSE RETRACTION OF SIX MAXILLARY ANTERIOR TEETH IN LABIAL ORTHODONTICS. J MECH MED BIOL 2020. [DOI: 10.1142/s0219519419500660] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The orthodontists generally do not recommend application of force system above the archwire level owing to additional attachments and patient’s discomfort. Hence, the present research study focusses on application of retraction force system at the archwire level. The objective of this study is to specify an optimum combination of archwire and bracket slot size for en-masse (simultaneous) parallel retraction of six maxillary anterior teeth in labial orthodontics (LaO). In this research study, the concept (theoretical) model has been developed based on simple principles of mechanics to estimate the torque generated by different sizes of archwire in bracket slots. Based on torque value, retraction force developed by each combination of archwire and slot size was determined and compared with required retraction force of 150 gram-force on each side of sagittal plane. For combination of [Formula: see text] inch stalinless steel SS archwire and 0.022 inch SS bracket slot, magnitude of computed retraction force matched closely with aforementioned required force than other combinations and hence, it is recommended in the present research study. The validation of selected combination of archwire and bracket slot size was done successfully by in vivo (clinical) experimentation on three patients. Thus, it proves that the aforementioned combination of archwire and bracket slot size is more suitable than others for retraction force system applied at archwire level.
Collapse
Affiliation(s)
- ABHISHEK M. THOTE
- School of Mechanical Engineering, MIT-World Peace University, Pune, Maharashtra, India
| | - RASHMI V. UDDANWADIKER
- Department of Mechanical Engineering, Visvesvaraya National Institute of Technology, Nagpur, Maharashtra, India
| | - KRISHNA SHARMA
- Private Practice, Toothart Clinic, Nagpur, Maharashtra, India
| | - SUNITA SHRIVASTAVA
- Department of Orthodontics, Sharad Pawar Dental College, Wardha, Maharashtra, India
| | - VENKATESWAR REDDY
- Department of Mechanical Engineering, MLR Institute of Technology, Hyderabad, Telangana, India
| |
Collapse
|
21
|
Liu Y, Jiang F, Chen J. Can interfaces at bracket-wire and between teeth in multi-teeth finite element model be simplified? INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2019; 35:e3169. [PMID: 30427587 DOI: 10.1002/cnm.3169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 10/31/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
OBJECTIVE Finite element (FE) method's correctness depends heavily on modeling method. This study aimed at determining whether the interfaces at bracket-wire and between teeth can be simplified for multi-teeth FE analysis. METHOD A three-dimensional FE model of a mandible was created from cone-beam computed tomography scan. Due to symmetry, only a half of the mandible was modeled, which consisted of five teeth (first premolar extraction and only first molar), brackets and archwire, periodontal ligament (PDL), cortical bone, and cancellous bone. All the bone, teeth, and PDL were considered to be isotropic and linear. The En-masse retraction case was simulated. A detailed model, which has contact elements between the bracket and archwire and between teeth, was developed to allow relative motion at the interfaces. A model with simplified interfacial conditions, which does not allow the relative motion, was also created. The stresses and displacements as results of the treatment on these two models were calculated and compared. RESULTS The stress and displacement distributions from the detailed model were more close to reality based on the expected displacement pattern of the clinical case than from the simplified model. The maximum stresses from the two methods were also different. The highest stress from the detailed model is twice as high as from the simplified model. CONCLUSIONS The detailed model provides much more reasonable results than the simplified model. Thus, the simplified model should not be used to replace the detailed model if the stress magnitude and highest stress location are the expected outcomes.
Collapse
Affiliation(s)
- Yanzhi Liu
- Department of Mechanical Engineering, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN, USA
| | - Feifei Jiang
- Department of Mechanical Engineering, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN, USA
| | - Jie Chen
- Department of Mechanical Engineering, Department of Oral Facial Genetics, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| |
Collapse
|