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Caragiuli M, Candelari M, Zalunardo F, Bruno G, De Stefani A, Brunzini A, Mandolini M. Effects of Oral Appliances for Obstructive Sleep Apnoea in Reduced Periodontium: A Finite Element Analysis. Int Dent J 2024:S0020-6539(24)00139-4. [PMID: 38839530 DOI: 10.1016/j.identj.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 04/21/2024] [Accepted: 05/07/2024] [Indexed: 06/07/2024] Open
Abstract
BACKGROUND AND OBJECTIVE In the literature, no studies correlate the effects of mandibular advancement devices (MADs) with different titration systems to periodontitis. Through a finite element analysis (FEA), this study investigates the effects generated on periodontal ligaments (PDLs) and teeth by four commercial MADs in periodontal health and with 15% bone resorption. METHODS Four MADs (Somnodent Flex™, Somnodent Avant™, Orthoapnea™, and Herbst™) were digitalised starting from the impressions of a patient's dental arches. A force of 11.18 N, representing an advancement of 9.5 mm, was applied, and a FEA was subsequently performed. After measuring the stresses and displacements on the PDLs and teeth in healthy periodontal conditions, the vertical dimension of the alveolar bone was reduced by 15%, and measurements were repeated. RESULTS In terms of PDL stress, Herbst™ is the device which guarantees a more uniform increment in case of the first stage of periodontitis (+7% for mandibular and maxillary PDLs compared to the healthy condition). For Somnodent™ devices, the PDLs stress increment is almost null for mandibular PDLs but much higher than Herbst™ for maxillary PDLs (+17% and +21% for Flex™ and Avant™). Orthoapnea™ determines a PDL stress augmentation between the other devices (+16% and +7%, respectively, for maxillary and mandibular PDLs). Concerning teeth movement, Herbst™ and Orthoapnea™ determine a lower and more uniform displacement than Somnodent devices. CONCLUSIONS The stress distribution and teeth displacement are strictly related to MAD geometry. Since its minor effects on teeth and PDLs, the Herbst™ could be more appropriate in patients with periodontitis.
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Affiliation(s)
- Manila Caragiuli
- Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Ancona, Italy.
| | - Mara Candelari
- Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Ancona, Italy
| | - Francesca Zalunardo
- Department of Neuroscience, Dental Clinic, Section of Dentistry, University of Padua, Padua, Italy
| | - Giovanni Bruno
- Department of Neuroscience, Dental Clinic, Section of Dentistry, University of Padua, Padua, Italy; Department of Industrial Engineering, University Tor Vergata, Rome, Italy
| | - Alberto De Stefani
- Department of Neuroscience, Dental Clinic, Section of Dentistry, University of Padua, Padua, Italy; Department of Pharmacological Sciences, University of Padua, Padua, Italy
| | - Agnese Brunzini
- Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Ancona, Italy
| | - Marco Mandolini
- Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Ancona, Italy
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Antonarakis GS, Zekeridou A, Kiliaridis S, Giannopoulou C. Periodontal considerations during orthodontic intrusion and extrusion in healthy and reduced periodontium. Periodontol 2000 2024. [PMID: 38831560 DOI: 10.1111/prd.12578] [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: 10/17/2023] [Revised: 04/30/2024] [Accepted: 05/13/2024] [Indexed: 06/05/2024]
Abstract
In patients with advanced periodontal disease, pathological tooth migration may occur, which may require subsequent orthodontic treatment for both aesthetic and functional purposes. When planning orthodontic treatment mechanics, intrusive or extrusive forces are frequently indicated. Understanding tissue reactions during these movements is essential for clinicians when devising a comprehensive orthodontic-periodontal treatment plan. This knowledge enables clinicians to be fully aware of and account for the potential effects on the surrounding tissues. The majority of our understanding regarding the behavior of periodontal tissues in both healthy and compromised periodontal conditions is derived from animal studies. These studies offer the advantage of conducting histological and other assessments that would not be feasible in human research. Human studies are nevertheless invaluable in being able to understand the clinically relevant response elicited by the periodontal tissues following orthodontic tooth movement. Animal and human data show that in dentitions with reduced periodontal support, orthodontic intrusion of the teeth does not induce periodontal damage, provided the periodontal tissues do not have inflammation and plaque control with excellent oral hygiene is maintained. On the contrary, when inflammation is not fully controlled, orthodontic intrusion may accelerate the progression of periodontal destruction, with bacterial plaque remnants being displaced subgingivally, leading to further loss of attachment. Orthodontic extrusion, on the other hand, does not seem to cause further periodontal breakdown in dentitions with reduced periodontal support, even in cases with deficient plaque control. This is attributed to the nature of the tooth movement, which directs any plaque remnants coronally (supragingivally), reducing the risk of adverse effects on the periodontal tissues. This specific type of tooth movement can be leveraged to benefit periodontal conditions by facilitating the regeneration of lost hard and soft periodontal tissues in a coronal direction. As a result, orthodontic extrusion can be employed in implant site development, offering an advantageous alternative to more invasive surgical procedures like bone grafting. Regardless of the tooth movement prescribed, when periodontal involvement is present, it is essential to prioritize periodontal therapy before commencing orthodontic treatment. Adequate plaque control is also imperative for successful outcomes. Additionally, utilizing light orthodontic forces is advisable to achieve efficient tooth movement while minimizing the risk of adverse effects, notably root resorption. By adhering to these principles, a more favorable and effective combined orthodontic-periodontal approach can be ensured. The present article describes indications, mechanisms, side effects, and histological and clinical evidence supporting orthodontic extrusion and intrusion in intact and reduced periodontal conditions.
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Affiliation(s)
- Gregory S Antonarakis
- Division of Orthodontics, University Clinics of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Alkisti Zekeridou
- Division of Regenerative Dental Medicine and Periodontology, University Clinics of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Stavros Kiliaridis
- Division of Orthodontics, University Clinics of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Department of Orthodontics and Dentofacial Orthopaedics, University of Bern, Bern, Switzerland
| | - Catherine Giannopoulou
- Division of Regenerative Dental Medicine and Periodontology, University Clinics of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Liu X, Wan X, Sui B, Hu Q, Liu Z, Ding T, Zhao J, Chen Y, Wang ZL, Li L. Piezoelectric hydrogel for treatment of periodontitis through bioenergetic activation. Bioact Mater 2024; 35:346-361. [PMID: 38379699 PMCID: PMC10876489 DOI: 10.1016/j.bioactmat.2024.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 01/26/2024] [Accepted: 02/07/2024] [Indexed: 02/22/2024] Open
Abstract
The impaired differentiation ability of resident cells and disordered immune microenvironment in periodontitis pose a huge challenge for bone regeneration. Herein, we construct a piezoelectric hydrogel to rescue the impaired osteogenic capability and rebuild the regenerative immune microenvironment through bioenergetic activation. Under local mechanical stress, the piezoelectric hydrogel generated piezopotential that initiates osteogenic differentiation of inflammatory periodontal ligament stem cells (PDLSCs) via modulating energy metabolism and promoting adenosine triphosphate (ATP) synthesis. Moreover, it also reshapes an anti-inflammatory and pro-regenerative niche through switching M1 macrophages to the M2 phenotype. The synergy of tilapia gelatin and piezoelectric stimulation enhances in situ regeneration in periodontal inflammatory defects of rats. These findings pave a new pathway for treating periodontitis and other immune-related bone defects through piezoelectric stimulation-enabled energy metabolism modulation and immunomodulation.
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Affiliation(s)
- Xin Liu
- Department of Dental Materials, Shanghai Biomaterials Research & Testing Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, PR China
| | - Xingyi Wan
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Baiyan Sui
- Department of Dental Materials, Shanghai Biomaterials Research & Testing Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, PR China
| | - Quanhong Hu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, PR China
| | - Zhirong Liu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Tingting Ding
- Department of Dental Materials, Shanghai Biomaterials Research & Testing Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, PR China
| | - Jiao Zhao
- Department of Dental Materials, Shanghai Biomaterials Research & Testing Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, PR China
| | - Yuxiao Chen
- Department of Dental Materials, Shanghai Biomaterials Research & Testing Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, 200011, PR China
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Linlin Li
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
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Kökan EC, Atik Y, Özüpek Ş, Podnos E, Erişen R. Finite element study of the fatigue behaviour of nickel-titanium endodontic files utilised with pecking motion technique. AUST ENDOD J 2024; 50:97-109. [PMID: 37994546 DOI: 10.1111/aej.12813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/18/2023] [Accepted: 10/30/2023] [Indexed: 11/24/2023]
Abstract
The purpose of the study is to evaluate the influence of the pecking motion (reciprocal axial motion) surgical technique on the durability behaviour of the Nickel-Titanium endodontic files using Finite Element Analysis (FEA). A commonly used endodontic file, ProTaper Universal F2, is selected for the study. Root canal treatment procedure is simulated on a test-bench (simulated root canal) proposed by G. Gambarini for cyclic fatigue loading of endodontic files with and without the pecking motion via FEA. The hysteresis energy density is used as evaluation criteria for low cycle fatigue life estimation of Shape Memory Alloy files. In an additional study, the root canal treatment procedure is also simulated for an FEA model of a molar tooth with significant root canal curvature to understand the influence of the realistic curvature of a root canal on the fatigue behaviour of endodontic files. For the simulated root canal, analysis accurately predicts the endodontic file's failure location, and fatigue life estimation based on the hysteresis energy density is shown to increase significantly with the introduction of the pecking motion, an observation confirmed by reported experimental results. Molar tooth simulations reveal greater file fatigue resistance than in simulated root canals, confirming the pecking motion's efficacy in enhancing file durability, even in real root canal conditions. Simulations indicate that the pecking motion technique increases the fatigue life of endodontic files for simulated as well as real root canals and the hysteresis energy is confirmed as an acceptable parameter to quantify fatigue life of Nickel-Titanium endodontic files.
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Affiliation(s)
- Eyüp Can Kökan
- Department of Mechanical Engineering, Boğaziçi University, İstanbul, Turkey
| | - Yasin Atik
- Department of Mechanical Engineering, Boğaziçi University, İstanbul, Turkey
| | - Şebnem Özüpek
- Department of Mechanical Engineering, Boğaziçi University, İstanbul, Turkey
| | - Evgeny Podnos
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, Texas, USA
| | - Raif Erişen
- Department of Clinical Sciences, Nişantaşı University, İstanbul, Turkey
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Abramson Z, Oh C, Wells M, Choudhri AF, Whitehead MT. CT and MR Appearance of Teeth: Analysis of Anatomy and Embryology and Implications for Disease. J Clin Med 2024; 13:1187. [PMID: 38592028 PMCID: PMC10932355 DOI: 10.3390/jcm13051187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 02/12/2024] [Accepted: 02/18/2024] [Indexed: 04/10/2024] Open
Abstract
Abnormalities of dental development and anatomy may suggest the presence of congenital or acquired anomalies. The detection of abnormalities, therefore, is an important skill for radiologists to achieve. Knowledge of dental embryology and an understanding of the radiologic appearances of teeth at various stages of maturation are required for the appreciation of abnormal dental development. While many tooth abnormalities are well-depicted on dedicated dental radiographs, the first encounter with a dental anomaly may be by a radiologist on a computed tomographic (CT) or magnetic resonance (MR) exam performed for other reasons. This article depicts normal dental anatomy and development, describing the appearance of the neonatal dentition on CT and MRI, the modalities most often encountered by clinical radiologists. The radiology and dental literature are reviewed, and key concepts are illustrated with supplemental cases from our institution. The value of knowledge of dental development is investigated using the analysis of consecutive MR brain examinations. Finally, the anatomical principles are applied to the diagnosis of odontogenic infection on CT. Through analysis of the literature and case data, the contrast of dental pathology with normal anatomy and development facilitates the detection and characterization of both congenital and acquired dental disease.
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Affiliation(s)
- Zachary Abramson
- Clinical Radiology, Radiologist, Body Imaging, Department of Diagnostic Imaging, St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Chris Oh
- Quantum Radiology, 790 Church St., Suite 400, Marietta, GA 30060, USA;
| | - Martha Wells
- Department of Surgery, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA;
| | - Asim F. Choudhri
- Department of Radiology, Le Bonheur Children’s Hospital, University of Tennessee Health Science Center, 50 N. Dunlap St., Memphis, TN 38103, USA;
| | - Matthew T. Whitehead
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA;
- Division of Neuroradiology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
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Wu B, Li N, Liu M, Cheng K, Jiang D, Yi Y, Ma S, Yan B, Lu Y. Construction of Human Periodontal Ligament Constitutive Model Based on Collagen Fiber Content. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6582. [PMID: 37834722 PMCID: PMC10573969 DOI: 10.3390/ma16196582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 10/15/2023]
Abstract
Periodontal ligament (PDL) is mainly composed of collagen fiber bundles, and the content of collagen fiber is an important factor affecting the mechanical properties of PDL. Based on this, the purpose of this study is to explore the effect of the PDL collagen fiber content on its viscoelastic mechanical behavior. Transverse and longitudinal samples of different regions of PDL were obtained from the human maxilla. The fiber content at different regions of human PDL was quantitatively measured using image processing software, and a new viscoelastic constitutive model was constructed based on the fiber content. The nano-indentation experiment was carried out with a loading rate of 0.5 mN·s-1, a peak load of 3 mN, and a holding time of 200 s, and the model parameters were obtained through the experiment data. The results showed that with the increase of fiber content, the deformation resistance of PDL also increased, and compared with the neck and middle region, the compressive strain in the apical region of PDL was the largest. The range of reduced elastic modulus of human PDL was calculated to be 0.39~5.08 MPa. The results of the experimental data and the viscoelastic constitutive model fit well, indicating that the model can well describe the viscoelastic behavior of human PDL.
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Affiliation(s)
- Bin Wu
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; (B.W.); (N.L.); (D.J.); (Y.Y.)
| | - Na Li
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; (B.W.); (N.L.); (D.J.); (Y.Y.)
| | - Mao Liu
- Department of Orthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing 210029, China;
- Jiangsu Province Key Laboratory of Oral Diseases, Nanjing 210029, China
- Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing 210029, China
| | - Ke Cheng
- College of Mechanical Engineering, Southeast University, Nanjing 210018, China;
| | - Di Jiang
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; (B.W.); (N.L.); (D.J.); (Y.Y.)
| | - Yang Yi
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; (B.W.); (N.L.); (D.J.); (Y.Y.)
| | - Songyun Ma
- Institute of General Mechanics, RWTH-Aachen University, 52062 Aachen, Germany;
| | - Bin Yan
- Department of Orthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing 210029, China;
- Jiangsu Province Key Laboratory of Oral Diseases, Nanjing 210029, China
- Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing 210029, China
- College of Mechanical Engineering, Southeast University, Nanjing 210018, China;
| | - Yi Lu
- College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; (B.W.); (N.L.); (D.J.); (Y.Y.)
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Moga RA, Olteanu CD, Buru SM, Botez MD, Delean AG. Cortical and Trabecular Bone Stress Assessment during Periodontal Breakdown-A Comparative Finite Element Analysis of Multiple Failure Criteria. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1462. [PMID: 37629752 PMCID: PMC10456684 DOI: 10.3390/medicina59081462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/06/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023]
Abstract
Background and Objectives: This numerical analysis investigated the biomechanical behavior of the mandibular bone as a structure subjected to 0.5 N of orthodontic force during periodontal breakdown. Additionally, the suitability of the five most used failure criteria (Von Mises (VM), Tresca (T), maximum principal (S1), minimum principal (S3), and hydrostatic pressure (HP)) for the study of bone was assessed, and a single criterion was identified for the study of teeth and the surrounding periodontium (by performing correlations with other FEA studies). Materials and Methods: The finite element analysis (FEA) employed 405 simulations over eighty-one mandibular models with variable levels of bone loss (0-8 mm) and five orthodontic movements (intrusion, extrusion, tipping, rotation, and translation). For the numerical analysis of bone, the ductile failure criteria are suitable (T and VM are adequate for the study of bone), with Tresca being more suited. S1, S3, and HP criteria, due to their distinctive design dedicated to brittle materials and liquids/gas, only occasionally correctly described the bone stress distribution. Results: Only T and VM displayed a coherent and correlated gradual stress increase pattern for all five movements and levels of the periodontal breakdown. The quantitative values provided by T and VM were the highest (for each movement and level of bone loss) among all five criteria. The MHP (maximum physiological hydrostatic pressure) was exceeded in all simulations since the mandibular bone is anatomically less vascularized, and the ischemic risks are reduced. Only T and VM displayed a correlated (both qualitative and quantitative) stress increase for all five movements. Both T and VM displayed rotation and translation, closely followed by tipping, as stressful movements, while intrusion and extrusion were less stressful for the mandibular bone. Conclusions: Based on correlations with earlier numerical studies on the same models and boundary conditions, T seems better suited as a single unitary failure criterion for the study of teeth and the surrounding periodontium.
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Affiliation(s)
- Radu Andrei Moga
- Department of Cariology, Endodontics and Oral Pathology, School of Dental Medicine, University of Medicine and Pharmacy Iuliu Hatieganu, Str. Motilor 33, 400001 Cluj-Napoca, Romania;
| | - Cristian Doru Olteanu
- Department of Orthodontics, School of Dental Medicine, University of Medicine and Pharmacy Iuliu Hatieganu, Str. Avram Iancu 31, 400083 Cluj-Napoca, Romania
| | - Stefan Marius Buru
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania; (S.M.B.); (M.D.B.)
| | - Mircea Daniel Botez
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania; (S.M.B.); (M.D.B.)
| | - Ada Gabriela Delean
- Department of Cariology, Endodontics and Oral Pathology, School of Dental Medicine, University of Medicine and Pharmacy Iuliu Hatieganu, Str. Motilor 33, 400001 Cluj-Napoca, Romania;
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Zhang Y, Gao J, Wang X, Wang J, Zhang X, Fang S, Wang W, Ma Y, Jin Z. Biomechanical factors in the open gingival embrasure region during the intrusion of mandibular incisors: A new model through finite element analysis. Front Bioeng Biotechnol 2023; 11:1149472. [PMID: 37064220 PMCID: PMC10090539 DOI: 10.3389/fbioe.2023.1149472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023] Open
Abstract
Introduction: Open gingival embrasure (OGE) is a common complication in adults following clear aligner therapy and the influence of gingival or alveolar bone biotype on OGE is of great concern. Unfortunately, due to the limited number of patients with clearaligner therapy and the clinical methods to distinguish the gingival biotype of patients being invasive, it is difficult to carry out clinical studies on the gingival or alveolar bone biotype of the OGE. In the meanwhile, the detailed biomechanics of the occurrence of OGE remains unknown. The goal of this study was to establish a new model to simulate the virtual space region, namely, the OGE region, to investigate the relationship between alveolar bone biotype and the occurrence of OGE, and explore potential biomechanical factors related to OGE.Methods: The OGE region in the interproximal space was established using a filler with a very low modulus of elasticity (1 × 10−6 MPa). To illustrate the biomechanics of OGE more exhaustively, a line was created at the top of the alveolar crest along the proximal tooth root. FEA was then used to analyze the biomechanics of the surrounding tissues, the OGE region and the line at the top of the alveolar crest along the proximal tooth root of the central incisor under two different labial bone thicknesses (thick and thin) with an axial inclination of 80°, 90° and 100°.Results: During intrusion of the incisors in clear aligner therapy, as inclination increased or bone tissue became thinner, the stress in the surrounding tissues [tooth root, alveolar crest, and periodontal ligament (PDL)] was greater. In the OGE region and interproximal alveolar crest, the strain increased with increasing inclination and labial bone thinning. The results from the line at the top of the alveolar crest along the proximal tooth root showed more detailed biomechanics: In all groups, stress and strain were focused on the mesial-labial alveolar crest. Interestingly, our results also demonstrated that when OGE occurs, other complications may arise, including root resorption and bone dehiscence.
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Affiliation(s)
- Yubohan Zhang
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi’an, China
| | - Jie Gao
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi’an, China
| | - Xu Wang
- Xijing Hospital of Digestive Diseases, Air Force Medical University, Xi’an, China
| | - Jihong Wang
- The First People’s Hospital of Xianyang, Xianyang, Shaanxi Province, China
| | - Xu Zhang
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi’an, China
| | - Shishu Fang
- General Hospital of Southern Theater Command of the Chinese People’s Liberation Army, Guangzhou, China
| | - Wei Wang
- Urumql DW Innovation InfoTech Co., Ltd., Xinjiang, China
| | - Yanning Ma
- Stomatological Hospital, Shanxi Medical University, Taiyuan, Shanxi Province, China
- *Correspondence: Yanning Ma, ; Zuolin Jin,
| | - Zuolin Jin
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi’an, China
- *Correspondence: Yanning Ma, ; Zuolin Jin,
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Moga RA, Olteanu CD, Daniel BM, Buru SM. Finite Elements Analysis of Tooth-A Comparative Analysis of Multiple Failure Criteria. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:ijerph20054133. [PMID: 36901151 PMCID: PMC10002102 DOI: 10.3390/ijerph20054133] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/19/2023] [Accepted: 02/23/2023] [Indexed: 06/01/2023]
Abstract
Herein Finite elements analysis (FEA) study assesses the adequacy and accuracy of five failure criteria (Von Mises (VM), Tresca, maximum principal (S1), minimum principal (S3), and Hydrostatic pressure) for the study of tooth as a structure (made of enamel, dentin, and cement), along with its stress absorption-dissipation ability. Eighty-one 3D models of the second lower premolar (with intact and 1-8 mm reduced periodontium) were subjected to five orthodontic forces (intrusion, extrusion, tipping, rotation, and translation) of 0.5 N (approx. 50 gf) (in a total of 405 FEA simulations). Only the Tresca and VM criteria showed biomechanically correct stress display during the 0-8 mm periodontal breakdown simulation, while the other three showed various unusual biomechanical stress display. All five failure criteria displayed comparable quantitative stress results (with Tresca and VM producing the highest of all), showing the rotational and translational movements to produce the highest amount of stress, while intrusion and extrusion, the lowest. The tooth structure absorbed and dissipated most of the stress produced by the orthodontic loads (from a total of 0.5 N/50 gf only 0.125 N/12.5 gf reached PDL and 0.01 N/1 gf the pulp and NVB). The Tresca criterion seems to be more accurate than Von Mises for the study of tooth as structure.
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Affiliation(s)
- Radu Andrei Moga
- Department of Cariology, Endodontics and Oral Pathology, School of Dental Medicine, University of Medicine and Pharmacy Iuliu Hatieganu, Str. Motilor 33, 400001 Cluj-Napoca, Romania
| | - Cristian Doru Olteanu
- Department of Orthodontics, School of Dental Medicine, University of Medicine and Pharmacy Iuliu Hatieganu, Str. Avram Iancu 31, 400083 Cluj-Napoca, Romania
| | - Botez Mircea Daniel
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania
| | - Stefan Marius Buru
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania
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Moga RA, Olteanu CD, Botez M, Buru SM. Assessment of the Maximum Amount of Orthodontic Force for Dental Pulp and Apical Neuro-Vascular Bundle in Intact and Reduced Periodontium on Bicuspids (Part II). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:1179. [PMID: 36673936 PMCID: PMC9859427 DOI: 10.3390/ijerph20021179] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 01/04/2023] [Accepted: 01/07/2023] [Indexed: 06/01/2023]
Abstract
This study examines 0.6 N-4.8 N as the maximum orthodontic force to be applied to dental pulp and apical NVB on intact and 1-8 mm reduced periodontal-ligament (PDL), in connection with movement and ischemic, necrotic and resorptive risk. In addition, it examines whether the Tresca finite-element-analysis (FEA) criterion is more adequate for the examination of dental pulp and its apical NVB. Eighty-one (nine patients, with nine models for each patient) anatomically correct models of the periodontium, with the second lower-premolar reconstructed with its apical NVB and dental pulp were assembled, based on X-ray CBCT (cone-beam-computed-tomography) examinations and subjected to 0.6 N, 1.2 N, 2.4 N and 4.8 N of intrusion, extrusion, translation, rotation, and tipping. The Tresca failure criterion was applied, and the shear stress was assessed. Forces of 0.6 N, 1.2 N, and 2.4 N had negligible effects on apical NVB and dental pulp up to 8 mm of periodontal breakdown. A force of 4.8 N was safely applied to apical NVB on the intact periodontium only. Rotation and tipping seemed to be the most invasive movements for the apical NVB. For the dental pulp, only the translation and rotation movements seemed to display a particular risk of ischemia, necrosis, and internal orthodontic-resorption for both coronal (0-8 mm of loss) and radicular pulp (4-8 mm of loss), despite the amount of stress being lower than the MHP. The Tresca failure criterion seems more suitable than other criteria for apical NVB and dental pulp.
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Affiliation(s)
- Radu Andrei Moga
- Department of Cariology, Endodontics and Oral Pathology, School of Dental Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Str. Motilor 33, 400001 Cluj-Napoca, Romania
| | - Cristian Doru Olteanu
- Department of Orthodontics, School of Dental Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, Str. Avram Iancu 31, 400083 Cluj-Napoca, Romania
| | - Mircea Botez
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania
| | - Stefan Marius Buru
- Department of Structural Mechanics, School of Civil Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania
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Construction of hyperelastic model of human periodontal ligament based on collagen fibers distribution. J Mech Behav Biomed Mater 2022; 135:105484. [PMID: 36179616 DOI: 10.1016/j.jmbbm.2022.105484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/18/2022] [Accepted: 09/21/2022] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The human periodontal ligament (PDL) dominated by collagen fibers showed hyperelastic mechanical behavior under orthodontic force. Despite previous researches on the hyperelastic model of PDL, there were certain limitations because of the types of samples and the ignorance of distribution of collagen fibers. Therefore, the aim of this study was to quantify the effect of collagen fibers distribution of human PDL on its hyperelastic behavior. METHODS A total of 6 human PDL samples of root neck, root middle and root apex were cut from human maxillary central incisor and lateral incisor. The spatial angles of collagen fibers were observed by optical microscope, the hyperelastic model was constructed combined with the observation results. The quasi-static uniaxial tensile tests with displacement load 0.05 mm/min were carried out, and the test data were used to identify the parameters of model. RESULTS The mechanical behavior of human PDL conformed to the trend of hyperelastic materials, and greatly depended on the spatial angles of internal collagen fibers. The R2 value statistical fit of the constitutive model to the data is excellent (R2 > 0.98). This model could excellently describe the hyperelastic properties of human PDL. SIGNIFICANCE In this study, we quantitatively described the effect of spatial distribution of collagen fibers on the mechanical properties of human PDL. The accuracy of this model was verified by the uniaxial test data, and the relevant model parameters were acquired, which have certain reference value in subsequent researches on hyperelasticity of human PDL and clinical treatment.
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Dantas T, Rodrigues F, Araújo J, Vaz P, Silva F. Customized root-analogue dental implants - Procedure and errors associated with image acquisition, treatment, and manufacturing technology in an experimental study on a cadaver dog mandible. J Mech Behav Biomed Mater 2022; 133:105350. [DOI: 10.1016/j.jmbbm.2022.105350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/21/2022] [Accepted: 06/28/2022] [Indexed: 11/30/2022]
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Ramakrishnan AN, Röhrle O, Ludtka C, Varghese R, Koehler J, Kiesow A, Schwan S. Numerical study of the stress state on the oral mucosa and abutment tooth upon insertion of partial dentures in the mandible. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2022; 38:e3604. [PMID: 35419990 DOI: 10.1002/cnm.3604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/12/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
The introduction of a removable partial denture onto the dental arch significantly influences the mechanical stress characteristics of both the jawbone and oral mucosa. The aim of this study was to analyze the stress state caused by biting forces upon insertion of partial dentures into the assembly, and to understand the influence of the resulting contact pressure on its retention behavior. For this purpose, a numerical model of a removable partial denture is proposed based on 3D models developed using computer tomography data of the jawbone and the removable partial denture. The denture system rests on the oral mucosa surface and three abutment teeth. The application of bite forces on the denture generated a stick condition on the loaded regions of the denture-oral mucosa interface, which indicates positive retention of the denture onto the oral mucosa surface. Slip and negative retention were observed in the regions of the contact space that were not directly loaded. The contact pressures observed in the regions of the oral mucosa in contact with the denture were below the clinical pressure pain threshold value for soft tissue, which potentially lowers the risk of pain being experienced by denture users. Further, the variation of the retention behavior and contact pressures across different regions of the denture assembly was observed. Thus, there is a need for adhesives or restraining mechanisms for the denture system in order to avoid bending and deformation of sections of the denture as a consequence of the applied bite force.
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Affiliation(s)
- Anantha Narayanan Ramakrishnan
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, Germany
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
| | - Oliver Röhrle
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
| | - Christopher Ludtka
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida, USA
| | | | - Josephine Koehler
- Department of Prosthodontics, School of Dental Medicine, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Andreas Kiesow
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, Germany
| | - Stefan Schwan
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, Germany
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Tian T, Huang HY, Wang W, Shi B, Zheng Q, Li CH. Three-dimensional finite element analysis of the effect of alveolar cleft bone graft on the maxillofacial biomechanical stabilities of unilateral complete cleft lip and palate. Biomed Eng Online 2022; 21:31. [PMID: 35596229 PMCID: PMC9123812 DOI: 10.1186/s12938-022-01000-y] [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: 09/30/2021] [Accepted: 05/16/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The objective is to clarify the effect of alveolar cleft bone graft on maxillofacial biomechanical stabilities, the key areas when bone grafting and in which should be supplemented with bone graft once bone resorption occurred in UCCLP (unilateral complete cleft lip and palate). METHODS Maxillofacial CAD (computer aided design) models of non-bone graft and full maxilla cleft, full alveolar cleft bone graft, bone graft in other sites of the alveolar cleft were acquired by processing the UCCLP maxillofacial CT data in three-dimensional modeling software. The maxillofacial bone EQV (equivalent) stresses and bone suture EQV strains under occlusal states were obtained in the finite element analysis software. RESULTS Under corresponding occlusal states, the EQV stresses of maxilla, pterygoid process of sphenoid bone on the corresponding side and anterior alveolar arch on the non-cleft side were higher than other maxillofacial bones, the EQV strains of nasomaxillary, zygomaticomaxillary and pterygomaxillary suture on the corresponding side were higher than other maxillofacial bone sutures. The mean EQV strains of nasal raphe, the maximum EQV stresses of posterior alveolar arch on the non-cleft side, the mean and maximum EQV strains of nasomaxillary suture on the non-cleft side in full alveolar cleft bone graft model were all significantly lower than those in non-bone graft model. The mean EQV stresses of bilateral anterior alveolar arches, the maximum EQV stresses of maxilla and its alveolar arch on the cleft side in the model with bone graft in lower 1/3 of the alveolar cleft were significantly higher than those in full alveolar cleft bone graft model. CONCLUSIONS For UCCLP, bilateral maxillae, pterygoid processes of sphenoid bones and bilateral nasomaxillary, zygomaticomaxillary, pterygomaxillary sutures, anterior alveolar arch on the non-cleft side are the main occlusal load-bearing structures before and after alveolar cleft bone graft. Alveolar cleft bone graft mainly affects biomechanical stabilities of nasal raphe and posterior alveolar arch, nasomaxillary suture on the non-cleft side. The areas near nasal floor and in the middle of the alveolar cleft are the key sites when bone grafting, and should be supplemented with bone graft when the bone resorbed in these areas.
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Affiliation(s)
- Tao Tian
- West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China
| | - Han-Yao Huang
- West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China.,West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China
| | - Wei Wang
- Urumql DW Innovation InfoTech Co., Ltd., Urumqi, 830000, Xinjiang Uygur Autonomous Region, The People's Republic of China
| | - Bing Shi
- West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China.,West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China
| | - Qian Zheng
- West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China. .,West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China.
| | - Cheng-Hao Li
- West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China. .,West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan Province, The People's Republic of China.
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Finite element analysis of stress distribution in autotransplanted molars. J Dent 2022; 119:104082. [PMID: 35247471 DOI: 10.1016/j.jdent.2022.104082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 02/22/2022] [Accepted: 02/28/2022] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE The biomechanical response of an autotransplanted tooth and surrounding bone to occlusal loads is not well-known. The aim of the present study was to investigate the effect of root form and occlusal morphology on stress distribution in autotransplanted teeth and surrounding bone by using finite element analysis (FEA). METHODS Seven FEA models representing different autotransplanted tooth situations were generated: (a) first molar, (b) third molar, (c) root canal-treated third molar, (d) root canal-treated, ankylosed, third molar, (e) crowned third molar, (f) crowned and root canal-treated third molar, (g) root canal-treated, ankylosed, and crowned third molar. Load (200 N) was applied on the occlusal surface, parallel to the long axis of the tooth. Maximum von Mises stress values on dentin and surrounding bone were calculated for each situation. RESULTS Differences in stress distribution were observed among models. In ankylosed model, stress was primarily observed at the coronal region of the tooth. The stress was observed more at the coronal region of the tooth in crowned models compared with the non-crowned models. The stress distribution was homogeneous with root canal-treated and crowned autotransplanted tooth. CONCLUSIONS The occlusal morphology and root form of the autotransplanted tooth affected the stress in surrounding bone at the transfer site and the biomechanical response of the tooth. The stress was more homogeneous in crowned tooth and primarily observed at the coronal region, which may decrease the risk for root resorption. CLINICAL SIGNIFICANCE Root configuration, occlusal form and root canal treatment induce significant changes on the stress distribution on teeth and bone, including characteristic stress concentration and increased stress values. Clinicians can consider crowning autotransplanted teeth for improved stress distribution within the tooth structure.
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Chawla S, Deshmukh S. FEAr no more! Finite element analysis in orthodontics. JOURNAL OF THE INTERNATIONAL CLINICAL DENTAL RESEARCH ORGANIZATION 2022. [DOI: 10.4103/jicdro.jicdro_79_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Using FEM to Assess the Effect of Orthodontic Forces on Affected Periodontium. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11167183] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Orthodontic treatment in patients with no periodontal tissue breakdown vs. horizontal bone loss should be approached with caution even though it can bring significant benefits in terms of periodontal recovery and long-term success. We used the finite element method (FEM) to simulate various clinical scenarios regarding the periodontal involvement: healthy with no horizontal bone loss, moderate periodontal damage (33%) and severe horizontal bone loss (66%). Afterwards, forces of different magnitudes (0.25 N, 1 N, 3 N, and 5 N) were applied in order to observe the behavioral patterns. Through mathematical modeling, we recorded the maximum equivalent stresses (σ ech), the stresses on the direction of force application (σ c) and the displacements produced (f) in the whole tooth–periodontal ligament–alveolar bone complex with various degrees of periodontal damage. The magnitude of lingualization forces in the lower anterior teeth influences primarily the values of equivalent tension, then those of the tensions in the direction in which the force is applied, and lastly those of the displacement of the lower central incisor. However, in the case of the lower lateral incisor, it influences primarily the values of the tensions in the direction in which the force is applied, then those of equivalent tensions, and lastly those of displacement. Anatomical particularities should also be considered since they may contribute to increased periodontal risk in case of lingualization of the LLI compared to that of the LCI, with a potential emergence of the “wedge effect”. To minimize periodontal hazards, the orthodontic force applied on anterior teeth with affected periodontium should not exceed 1 N.
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Jain A, Prasantha GS, Mathew S, Sabrish S. Analysis of stress in periodontium associated with orthodontic tooth movement: a three dimensional finite element analysis. Comput Methods Biomech Biomed Engin 2021; 24:1841-1853. [PMID: 33982607 DOI: 10.1080/10255842.2021.1925255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
It is well known that the initiating factor for the biologic changes is the stress induced in the periodontal tissue; but as of now there is no gauge to measure the stress in the PDL directly. Therefore finite element model can be used to study the stress-strain relation through simulation of the PDL. The aim of the study was to simulate the stress response in the periodontium for different moment to farce ratios induced by tipping, translation, rotation, intrusion, extrusion and root torque by means of finite element method. The three-dimensional finite element model of the mandibular first molar was constructed. The pattern of Von misses stress and the maximum displacement of the mandibular molar was recorded on application of different combination of moment to force ratio. The periodontium was sensitive to changes in the load values. The stress pattern in the periodontal ligament for a lingually directed force without counterbalancing moments showed high concentration at the cervical level of the root. With addition of counter-tipping and counter-rotation moments, a relatively even distribution of stress throughout PDL was obtained. Additionally, high stress concentration was observed on the root surface at the furcation level for forces applied parallel to the long axis. Translation type of tooth movement showed relatively even distribution of the stress in the PDL and makes the tooth less susceptible to root resorption.
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Affiliation(s)
- Ankita Jain
- Department of Orthodontics, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India
| | - G S Prasantha
- Department of Orthodontics, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India
| | - Silju Mathew
- Department of Orthodontics, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India
| | - Sharanya Sabrish
- Department of Orthodontics, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India
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Tsai MT, Huang HL, Yang SG, Su KC, Fuh LJ, Hsu JT. Biomechanical analysis of occlusal modes on the periodontal ligament while orthodontic force applied. Clin Oral Investig 2021; 25:5661-5670. [PMID: 33665683 DOI: 10.1007/s00784-021-03868-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 02/25/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The study objective was to investigate four common occlusal modes by using the finite element (FE) method and to conduct a biomechanical analysis of the periodontal ligament (PDL) and surrounding bone when orthodontic force is applied. MATERIALS AND METHODS A complete mandibular FE model including teeth and the PDL was established on the basis of cone-beam computed tomography images of an artificial mandible. In the FE model, the left and right mandibular first premolars were not modeled because both canines required distal movement. In addition, four occlusal modes were simulated: incisal clench (INC), intercuspal position (ICP), right unilateral molar clench (RMOL), and right group function (RGF). The effects of these four occlusal modes on the von Mises stress and strain of the canine PDLs and bone were analyzed. RESULTS Occlusal mode strongly influenced the distribution and value of von Mises strain in the canine PDLs. The maximum von Mises strain values on the canine PDLs were 0.396, 1.811, 0.398, and 1.121 for INC, ICP, RMOL, and RGF, respectively. The four occlusal modes had smaller effects on strain distribution in the cortical bone, cancellous bone, and miniscrews. CONCLUSION Occlusal mode strongly influenced von Mises strain on the canine PDLs when orthodontic force was applied. CLINICAL RELEVANCE When an FE model is used to analyze the biomechanical behavior of orthodontic treatments, the effect of muscle forces caused by occlusion must be considered.
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Affiliation(s)
- Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan
| | - Heng-Li Huang
- School of Dentistry, College of Medicine, China Medical University, Taichung, 404, Taiwan
- Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan
| | - Shih-Guang Yang
- Master Program for Biomedical Engineering, China Medical University, Taichung, 404, Taiwan
| | - Kuo-Chih Su
- Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, 407, Taiwan
| | - Lih-Jyh Fuh
- School of Dentistry, College of Medicine, China Medical University, Taichung, 404, Taiwan
- Department of Dentistry, China Medical University and Hospital, Taichung, 404, Taiwan
| | - Jui-Ting Hsu
- School of Dentistry, College of Medicine, China Medical University, Taichung, 404, Taiwan.
- Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan.
- School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan.
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