1
|
Ubuzima P, Nshimiyimana E, Mukeshimana C, Mazimpaka P, Mugabo E, Mbyayingabo D, Mohamed AS, Habumugisha J. Exploring biological mechanisms in orthodontic tooth movement: Bridging the gap between basic research experiments and clinical applications - A comprehensive review. Ann Anat 2024; 255:152286. [PMID: 38810763 DOI: 10.1016/j.aanat.2024.152286] [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: 02/28/2024] [Revised: 04/21/2024] [Accepted: 05/21/2024] [Indexed: 05/31/2024]
Abstract
OBJECTIVES The molecular mechanisms behind orthodontic tooth movements (OTM) were investigated by clarifying the role of chemical messengers released by cells. METHODS Using the Cochrane library, Google scholar, and PubMed databases, a literature search was conducted, and studies published from 1984 to 2024 were considered. RESULTS Both bone growth and remodeling may occur when a tooth is subjected to mechanical stress. These chemicals have a significant effect on the stimulation and regulation of osteoblasts, osteoclasts, and osteocytes during alveolar bone remodeling. This regulation can take place in pathological conditions, such as periodontal diseases, or during OTM alone. This comprehensive review outlines key molecular mechanisms underlying OTM and explores various clinical assumptions associated with specific molecules and their functional domains during this process. Furthermore, clinical applications of certain molecules such as relaxin, prostaglandin E (PGE), and interleukin-1β (IL-1β) in accelerating OTM have been reported. Our findings underscore the existing gap between OTM clinical applications and basic research investigations. CONCLUSION A comprehensive understanding of orthodontic treatment is enriched by insights into biological systems. We reported the activation of osteoblasts, osteoclast precursor cells, osteoclasts, and osteocytes in response to mechanical stress, leading to targeted cellular and molecular interventions and facilitating rapid and regulated alveolar bone remodeling during tooth movement. Despite the shortcomings of clinical studies in accelerating OTM, this review highlights the crucial role of biological agents in this process and advocates for prioritizing high-quality human studies in future research to gain further insights from clinical trials.
Collapse
Affiliation(s)
- Pascal Ubuzima
- Department of Orthodontics, Affliated Hospital of Stomatology, Anhui Medical University Hefei, 69 Meishan Road, Hefei, Anhui, China; School of Dentistry, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Eugene Nshimiyimana
- Department of Orthodontics, Affliated Hospital of Stomatology, Anhui Medical University Hefei, 69 Meishan Road, Hefei, Anhui, China
| | - Christelle Mukeshimana
- Department of Orthodontics, Affliated Hospital of Stomatology, Anhui Medical University Hefei, 69 Meishan Road, Hefei, Anhui, China
| | - Patrick Mazimpaka
- School of Dentistry, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Eric Mugabo
- Department of Orthodontics, Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, 72 Xiangya Road, Changsha, Hunan 410000, China
| | - Dieudonne Mbyayingabo
- Department of Orthodontics, Stomatological Hospital of Xi'an Jiaotong University, 98 XiWu Road, Xi'an, Shaanxi 710004, China
| | | | - Janvier Habumugisha
- Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-cho, Kitaku, Okayama 700-8525, Japan; Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
| |
Collapse
|
2
|
Ciobotaru CD, Feștilă D, Dinte E, Muntean A, Boșca BA, Ionel A, Ilea A. Enhancement of Orthodontic Tooth Movement by Local Administration of Biofunctional Molecules: A Comprehensive Systematic Review. Pharmaceutics 2024; 16:984. [PMID: 39204329 PMCID: PMC11360669 DOI: 10.3390/pharmaceutics16080984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 07/20/2024] [Accepted: 07/22/2024] [Indexed: 09/04/2024] Open
Abstract
Enhancement of orthodontic tooth movement (OTM) through local administration of biofunctional molecules has become increasingly significant, particularly for adult patients seeking esthetic and functional improvements. This comprehensive systematic review analyzes the efficacy of various biofunctional molecules in modulating OTM, focusing on the method of administration and its feasibility, especially considering the potential for topical application. A search across multiple databases yielded 36 original articles of experimental human and animal OTM models, which examined biofunctional molecules capable of interfering with the biochemical reactions that cause tooth movement during orthodontic therapy, accelerating the OTM rate through their influence on bone metabolism (Calcitriol, Prostaglandins, Recombinant human Relaxin, RANKL and RANKL expression plasmid, growth factors, PTH, osteocalcin, vitamin C and E, biocompatible reduced graphene oxide, exogenous thyroxine, sclerostin protein, a specific EP4 agonist (ONO-AE1-329), carrageenan, and herbal extracts). The results indicated a variable efficacy in accelerating OTM, with Calcitriol, Prostaglandins (PGE1 and PGE2), RANKL, growth factors, and PTH, among others, showing promising outcomes. PGE1, PGE2, and Calcitriol experiments had statistically significant outcomes in both human and animal studies and, while other molecules underwent only animal testing, they could be validated in the future for human use. Notably, only one of the animal studies explored topical administration, which also suggests a future research direction. This review concluded that while certain biofunctional molecules demonstrated potential for OTM enhancement, the evidence is not definitive. The development of suitable topical formulations for human use could offer a patient-friendly alternative to injections, emphasizing comfort and cost-effectiveness. Future research should focus on overcoming current methodological limitations and advancing translational research to confirm these biomolecules' efficacy and safety in clinical orthodontic practice.
Collapse
Affiliation(s)
- Cristina Dora Ciobotaru
- Department of Oral Rehabilitation, Faculty of Dentistry, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (C.D.C.); (A.I.)
| | - Dana Feștilă
- Department of Orthodontics, Faculty of Dentistry, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
| | - Elena Dinte
- Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Pharmacy, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania;
| | - Alexandrina Muntean
- Department of Paediatric Dentistry, Faculty of Dentistry, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania;
| | - Bianca Adina Boșca
- Department of Histology, Faculty of Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania;
| | - Anca Ionel
- Department of Oral Rehabilitation, Faculty of Dentistry, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (C.D.C.); (A.I.)
| | - Aranka Ilea
- Department of Oral Rehabilitation, Faculty of Dentistry, “Iuliu Hațieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania; (C.D.C.); (A.I.)
| |
Collapse
|
3
|
Chen Y, Zhang C. Role of noncoding RNAs in orthodontic tooth movement: new insights into periodontium remodeling. J Transl Med 2023; 21:101. [PMID: 36759852 PMCID: PMC9912641 DOI: 10.1186/s12967-023-03951-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 02/01/2023] [Indexed: 02/11/2023] Open
Abstract
Orthodontic tooth movement (OTM) is biologically based on the spatiotemporal remodeling process in periodontium, the mechanisms of which remain obscure. Noncoding RNAs (ncRNAs), especially microRNAs and long noncoding RNAs, play a pivotal role in maintaining periodontal homeostasis at the transcriptional, post-transcriptional, and epigenetic levels. Under force stimuli, mechanosensitive ncRNAs with altered expression levels transduce mechanical load to modulate intracellular genes. These ncRNAs regulate the biomechanical responses of periodontium in the catabolic, anabolic, and coupling phases throughout OTM. To achieve this, down or upregulated ncRNAs actively participate in cell proliferation, differentiation, autophagy, inflammatory, immune, and neurovascular responses. This review highlights the regulatory mechanism of fine-tuning ncRNAs in periodontium remodeling during OTM, laying the foundation for safe, precise, and personalized orthodontic treatment.
Collapse
Affiliation(s)
- Yuming Chen
- grid.284723.80000 0000 8877 7471Stomatological Hospital, Southern Medical University, Guangzhou, 510280 China
| | - Chao Zhang
- Stomatological Hospital, Southern Medical University, Guangzhou, 510280, China.
| |
Collapse
|
4
|
Chaushu S, Klein Y, Mandelboim O, Barenholz Y, Fleissig O. Immune Changes Induced by Orthodontic Forces: A Critical Review. J Dent Res 2021; 101:11-20. [PMID: 34105404 DOI: 10.1177/00220345211016285] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Orthodontic tooth movement (OTM) is generated by a mechanical force that induces an aseptic inflammatory response in the periodontal tissues and a subsequent coordinated process of bone resorption and apposition. In this review, we critically summarize the current knowledge on the immune processes involved in OTM inflammation and provide a novel insight into the relationship between classical inflammation and clinical OTM phases. We found that most studies focused on the acute inflammatory process, which ignites the initial alveolar bone resorption. However, the exact mechanisms and the immune reactions involved in the following OTM phases remain obscure. Recent studies highlight the existence of a typical innate response of resident and extravasated immune cells, including granulocytes and natural killer (NK), dendritic, and γδT cells. Based on few available studies, we shed light on an active, albeit incomplete, process of resolution in the lag phase, supported by continuously elevated ratios of M1/M2 macrophage and receptor activator of nuclear factor κB ligand/osteoprotegerin ratio. This partial resolution enables tissue formation and creates the appropriate environment for a transition between the innate and adaptive arms of the immune system, essential for the tissue's return to homeostasis. Nevertheless, as the mechanical trigger persists, the resolution turns into a low-grade chronic inflammation, which underlies the next, acceleration/linear OTM phase. In this stage, the acute inflammation dampens, and a simultaneous process of bone resorption and formation occurs, driven by B and T cells of the adaptive immune arm. Excessive orthodontic forces or tooth movement in periodontally affected inflamed tissues may hamper resolution, leading to "maladaptive homeostasis" and tissue loss due to uncoupled bone resorption and formation. The review ends with a brief description of the translational studies on OTM immunomodulation. Future studies are necessary for further uncovering cellular and molecular immune targets and developing novel strategies for controlling OTM by local and sustained tuning of the inflammatory process.
Collapse
Affiliation(s)
- S Chaushu
- Department of Orthodontics, Faculty of Dental Medicine, The Hebrew University and Hadassah Medical Center, Jerusalem, Israel
| | - Y Klein
- Department of Orthodontics, Faculty of Dental Medicine, The Hebrew University and Hadassah Medical Center, Jerusalem, Israel.,Department of Biochemistry, Institute for Medical Research Israel-Canada, Hebrew University and Hadassah Medical Center, Jerusalem, Israel
| | - O Mandelboim
- Lautenberg Center for Cancer Immunology, Faculty of Medicine, The Hebrew University and Hadassah Medical Center, Jerusalem, Israel
| | - Y Barenholz
- Department of Biochemistry, Institute for Medical Research Israel-Canada, Hebrew University and Hadassah Medical Center, Jerusalem, Israel
| | - O Fleissig
- Department of Orthodontics, Faculty of Dental Medicine, The Hebrew University and Hadassah Medical Center, Jerusalem, Israel
| |
Collapse
|
5
|
Weider M, Schröder A, Docheva D, Rodrian G, Enderle I, Seidel CL, Andreev D, Wegner M, Bozec A, Deschner J, Kirschneck C, Proff P, Gölz L. A Human Periodontal Ligament Fibroblast Cell Line as a New Model to Study Periodontal Stress. Int J Mol Sci 2020; 21:ijms21217961. [PMID: 33120924 PMCID: PMC7663139 DOI: 10.3390/ijms21217961] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/19/2020] [Accepted: 10/23/2020] [Indexed: 01/22/2023] Open
Abstract
The periodontal ligament (PDL) is exposed to different kinds of mechanical stresses such as bite force or orthodontic tooth movement. A simple and efficient model to study molecular responses to mechanical stress is the application of compressive force onto primary human periodontal ligament fibroblasts via glass disks. Yet, this model suffers from the need for primary cells from human donors which have a limited proliferative capacity. Here we show that an immortalized cell line, PDL-hTERT, derived from primary human periodontal ligament fibroblasts exhibits characteristic responses to glass disk-mediated compressive force resembling those of primary cells. These responses include induction and secretion of pro-inflammatory markers, changes in expression of extracellular matrix-reorganizing genes and induction of genes related to angiogenesis, osteoblastogenesis and osteoclastogenesis. The fact that PDL-hTERT cells can easily be transfected broadens their usefulness, as molecular gain- and loss-of-function studies become feasible.
Collapse
Affiliation(s)
- Matthias Weider
- Department of Orthodontics and Orofacial Orthopedics, University Hospital of Erlangen, Friedrich-Alexander University Erlangen-Nuernberg, Glueckstr. 11, 91054 Erlangen, Germany; (G.R.); (I.E.); (C.L.S.); (L.G.)
- Correspondence: ; Tel.: + 49-9131-85-45653
| | - Agnes Schröder
- Department of Orthodontics, University Hospital Regensburg, Franz Josef Strauss Allee 11, 93053 Regensburg, Germany; (A.S.); (C.K.); (P.P.)
| | - Denitsa Docheva
- Experimental Trauma Surgery, Department of Trauma Surgery, University Hospital Regensburg, Franz Josef Strauss Allee 11, 93053 Regensburg, Germany;
| | - Gabriele Rodrian
- Department of Orthodontics and Orofacial Orthopedics, University Hospital of Erlangen, Friedrich-Alexander University Erlangen-Nuernberg, Glueckstr. 11, 91054 Erlangen, Germany; (G.R.); (I.E.); (C.L.S.); (L.G.)
| | - Isabel Enderle
- Department of Orthodontics and Orofacial Orthopedics, University Hospital of Erlangen, Friedrich-Alexander University Erlangen-Nuernberg, Glueckstr. 11, 91054 Erlangen, Germany; (G.R.); (I.E.); (C.L.S.); (L.G.)
| | - Corinna Lesley Seidel
- Department of Orthodontics and Orofacial Orthopedics, University Hospital of Erlangen, Friedrich-Alexander University Erlangen-Nuernberg, Glueckstr. 11, 91054 Erlangen, Germany; (G.R.); (I.E.); (C.L.S.); (L.G.)
| | - Darja Andreev
- Department of Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Glueckstr. 6, 91054 Erlangen, Germany; (D.A.); (A.B.)
| | - Michael Wegner
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Fahrstr. 17, 91054 Erlangen, Germany;
| | - Aline Bozec
- Department of Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Glueckstr. 6, 91054 Erlangen, Germany; (D.A.); (A.B.)
| | - James Deschner
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany;
| | - Christian Kirschneck
- Department of Orthodontics, University Hospital Regensburg, Franz Josef Strauss Allee 11, 93053 Regensburg, Germany; (A.S.); (C.K.); (P.P.)
| | - Peter Proff
- Department of Orthodontics, University Hospital Regensburg, Franz Josef Strauss Allee 11, 93053 Regensburg, Germany; (A.S.); (C.K.); (P.P.)
| | - Lina Gölz
- Department of Orthodontics and Orofacial Orthopedics, University Hospital of Erlangen, Friedrich-Alexander University Erlangen-Nuernberg, Glueckstr. 11, 91054 Erlangen, Germany; (G.R.); (I.E.); (C.L.S.); (L.G.)
| |
Collapse
|
6
|
Systematic review of biological therapy to accelerate orthodontic tooth movement in animals: Translational approach. Arch Oral Biol 2019; 110:104597. [PMID: 31739076 DOI: 10.1016/j.archoralbio.2019.104597] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/08/2019] [Accepted: 10/29/2019] [Indexed: 01/10/2023]
Abstract
OBJECTIVES To systematically review and evaluate what is known regarding contemporary biological therapy capable of accelerating orthodontic tooth movement (OTM) in animal model. MATERIALS AND METHODS MedLine, Scopus, Web of Science and OpenGrey were searched without restrictions until June 2019. Following study retrieval and selection, relevant data was extracted using a standardized table. Risk of bias (RoB) assessment was performed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool. RESULTS Fifty-one animal studies were included. Two biological therapies were identified as capable of accelerating the OTM: chemical methods (49 studies) and gene therapy (2 studies). The main substances that increased the OTM rate were cytokines (13 studies), followed by growth factors (6 studies) and hormones (5 studies). Most studies were assessed to be at unclear or high RoB. The application protocols, measurement and reporting of outcomes varied widely and methodologies were not adequately reported. CONCLUSIONS Although biological therapies to accelerate OTM have been widely tested and effective in preclinical studies, the validity of the evidence is flawed to support translational of these results. There is a need for well-designed experimental studies to translate these methods for clinical field.
Collapse
|
7
|
Moon JS, Lee SY, Kim JH, Choi YH, Yang DW, Kang JH, Ko HM, Cho JH, Koh JT, Kim WJ, Kim MS, Kim SH. Synergistic alveolar bone resorption by diabetic advanced glycation end products and mechanical forces. J Periodontol 2019; 90:1457-1469. [PMID: 31294467 DOI: 10.1002/jper.18-0453] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 01/08/2019] [Accepted: 03/01/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The association between diabetes mellitus (DM) and bone diseases is acknowledged. However, the mechanistic pathways leading to the alveolar bone (AB) destruction remain unclear. This study aims to elucidate the mechanical forces (MF)-induced AB destruction in DM and its underlying mechanism. METHODS In vivo periodontal tissue responses to MF were evaluated in rats with diabetes. In vitro human periodontal ligament (PDL) cells were either treated with advanced glycation end products (AGEs) alone or with AGEs and MF. RESULTS In vivo, the transcription of VEGF-A, colony stimulating factor-1 (CSF-1), and Ager was upregulated in diabetes, whereas changes in DDOST and Glo1 mRNAs were negligible. DM induced VEGF-A protein in the vascular cells of the PDL and subsequent angiogenesis, but DM itself did not induce osteoclastogenesis. MF-induced AB resorption was augmented in DM, and such augmentation was morphologically substantiated by the occasional undermining resorption as well as the frontal resorption of the AB by osteoclasts. The mRNA levels of CSF-1 and vascular endothelial growth factor (VEGF) during MF application were highly elevated in diabetes, compared with those of the normal counterparts. In vitro, AGEs treatment elevated Glut-1 and CSF-1 mRNA levels via the p38 and JNK pathways, whereas OGT and VEGF levels remained unchanged. Compressive MF especially caused upregulation of VEGF, CSF-1, and Glut-1 levels, and such upregulation was further enhanced by AGEs treatment. CONCLUSIONS Overloaded MF and AGEs metabolites may synergistically aggravate AB destruction by upregulating CSF-1 and VEGF. Therefore, regulating the compressive overloading of teeth, as well as the levels of diabetic AGEs, may prove to be an effective therapeutic modality for managing DM-induced AB destruction.
Collapse
Affiliation(s)
- Jung-Sun Moon
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Su-Young Lee
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jung-Ha Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Yoon-Ho Choi
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Dong-Wook Yang
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jee-Hae Kang
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Hyun-Mi Ko
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jin-Hyoung Cho
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jeong-Tae Koh
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Won-Jae Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Min-Seok Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Sun-Hun Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| |
Collapse
|
8
|
Qi J, Kitaura H, Shen WR, Kishikawa A, Ogawa S, Ohori F, Noguchi T, Marahleh A, Nara Y, Mizoguchi I. Establishment of an orthodontic retention mouse model and the effect of anti-c-Fms antibody on orthodontic relapse. PLoS One 2019; 14:e0214260. [PMID: 31216288 PMCID: PMC6583981 DOI: 10.1371/journal.pone.0214260] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/03/2019] [Indexed: 11/20/2022] Open
Abstract
Orthodontic relapse after orthodontic treatment is a major clinical issue in the dental field. However, the biological mechanism of orthodontic relapse is still unclear. This study aimed to establish a mouse model of orthodontic retention to examine how retention affects the rate and the amount of orthodontic relapse. We also sought to examine the role of osteoclastogenesis in relapse using an antibody to block the activity of M-CSF, an essential factor of osteoclast formation. Mice were treated with a nickel-titanium closed-coil spring that was fixed between the upper incisors and the upper-left first molar to move the first molar in a mesial direction over 12 days. Mice were randomly divided into three groups: group 1, no retention (G1); group 2, retention for 2 weeks (G2); and group 3, retention for 4 weeks (G3). In G2 and G3, a light-cured resin was placed in the space between the first and second molars as a model of retention. Orthodontic relapse was assessed by measuring changes in the dimensions of the gap created between the first and second molars. To assess the activity and role of osteoclasts, mice in G3 were injected with anti-c-Fms antibody or PBS, and assessed for changes in relapse distance and rate. Overall, we found that a longer retention period was associated with a slower rate of relapse and a shorter overall amount of relapse. In addition, inhibiting osteoclast formation using the anti-c-Fms antibody also reduced orthodontic relapse. These results suggest that M-CSF and/or its receptor could be potential therapeutic targets in the prevention and treatment of orthodontic relapse.
Collapse
Affiliation(s)
- Jiawei Qi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Hideki Kitaura
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
- * E-mail:
| | - Wei-Ren Shen
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Akiko Kishikawa
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Saika Ogawa
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Fumitoshi Ohori
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Takahiro Noguchi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Aseel Marahleh
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Yasuhiko Nara
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Itaru Mizoguchi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| |
Collapse
|
9
|
Matsumoto Y, Sringkarnboriboon S, Ono T. Proinflammatory mediators related to orthodontically induced periapical root resorption in rat mandibular molars. Eur J Orthod 2019; 39:686-691. [PMID: 28444165 DOI: 10.1093/ejo/cjx033] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Objectives The early phase of orthodontic tooth movement involves acute inflammatory response that may induce bone resorption. The aim of this study was to localize and quantify cells in the periodontium expressing proinflammatory mediators during orthodontically induced periapical root resorption of the rat mandibular molars. Materials and methods The levels of proinflammatory cytokines interleukin-1 (IL-1) α and β, tumor necrosis factor-α (TNF-α), inflammatory enzymes cyclooxygenase (COX) 1 and 2, and their product prostaglandin E2 (PGE2) in the root resorption site were compared to those in the corresponding area of the untreated periodontal ligament (PDL) of physiologically drifting teeth. Continuous heavy orthodontic force was applied to the mandibular first molar for 8 and 15 days while in occlusion to induce root resorption. Frozen sections including root resorption lacunae were analyzed for the activity of non-specific esterase (NSE) and tartrate-resistant acid phosphatase (TRAP) by enzyme histochemistry and for the expression of IL-1α, IL-1β, TNF-α, COX-1, COX-2, and PGE2 by immunohistochemistry. Results The active root resorption lacunae had significantly more TRAP-positive multinucleated odontoclasts, whereas the number of NSE-positive cells of the monocyte-macrophage lineage did not differ from that in the control PDL. Several types of periodontal cells exhibited a significant increase in the expression of IL-1α, IL-1β, TNF-α, COX-2, and PGE2 in the root resorption zone, while COX-1 was rarely detected. Conclusions These data suggest that proinflammatory mediators expressed in periodontal cells may synergistically promote apical root resorption in response to continuous heavy mechanical force applied to teeth.
Collapse
Affiliation(s)
- Yoshiro Matsumoto
- Department of Orthodontic Science, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | | | - Takashi Ono
- Department of Orthodontic Science, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| |
Collapse
|
10
|
Atsawasuwan P, Chen Y, Ganjawalla K, Kelling AL, Evans CA. Extracorporeal shockwave treatment impedes tooth movement in rats. Head Face Med 2018; 14:24. [PMID: 30419912 PMCID: PMC6233511 DOI: 10.1186/s13005-018-0181-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 10/24/2018] [Indexed: 12/22/2022] Open
Abstract
Background Accelerated tooth movement has been a topic of interest for orthodontic research recently. Surgically facilitated orthodontic treatment has been shown to be an effective approach to accelerate tooth movement; however, it remains invasive, requires additional surgery, and may increase post-operative complications. In this study, we evaluate the effects of extracorporeal shockwave treatment (ESWT), a non-invasive approach to regenerate alveolar bone, on orthodontic tooth movement in rats. Materials and methods Seventy-two male rats, aged 10 weeks old, were subjected to 10-cN closed-coil nickel-titanium springs for unilateral maxillary first molar tooth movement. One group of rats received a single treatment of extracorporeal shockwave treatment at 500 impulses at energy flux density 0.1 mJ/mm2, with a pulse rate of 5 pulses per second immediately after spring installation while the non-ESWT-treated group served as a control group. The rats were sacrificed at day 3, 7, 14, 21 and 28 for tooth movement evaluation and sample analyses. Faxitron radiography, histological, double bone labeling and gene expression analyses were performed. Serum biochemistry was evaluated at day 3, 7 and 28 of the study. Kruskal-Wallis analysis of variance was used to determine the mean difference among groups, and multiple comparisons were analyzed by Mann-Whitney-U tests with a significance level = 0.05. Results The results demonstrated that tooth movement in the ESWT-treated rats (0.11 ± 0.07 mm) was impeded compared to the tooth movement in the non-ESWT-treated rats (0.44 ± 0.09 mm). ESWT up-regulated several osteoblastic and osteoclastic gene markers and cytokines; however, the effects on osteoclasts were only transient. Double-fluorescence bone labeling demonstrated that osteoblastic activity increased after ESWT treatment. There was no difference in systemic RANKL/OPG ratio between groups. Conclusions ESWT at 500 impulse at energy flux density 0.1 mJ/mm2 increased osteoblast and osteoclast activities and imbalanced bone remodeling resulting in impeded tooth movement in rats.
Collapse
Affiliation(s)
- Phimon Atsawasuwan
- Department of Orthodontics, University of Illinois at Chicago, College of Dentistry, 801 S. Paulina St, Chicago, Illinois, 60612, USA.
| | - Yinghua Chen
- Department of Orthodontics, University of Illinois at Chicago, College of Dentistry, 801 S. Paulina St, Chicago, Illinois, 60612, USA
| | | | | | - Carla A Evans
- Department of Orthodontic and Dentofacial Orthopedics, Boston University, Boston, Massachusetts, USA
| |
Collapse
|
11
|
Krishnan V, Sanford RL, Davidovitch Z. Tooth movement biology and laboratory experiments: How useful are they to orthodontic practitioners? Semin Orthod 2017. [DOI: 10.1053/j.sodo.2017.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
12
|
Abstract
The tooth-periodontal ligament-alveolar bone complex acts symbiotically to dissipate the mechanical loads incurred during mastication and/or orthodontic tooth movement. The periodontal ligament functions both in the tension and compression. At the molecular and celleular levels, the loads in the periodontal ligament trigger mechanobiological events in the alveolar bone, which leads to bone modeling and remodeling. The current review focuses on the bone response to mechanical loading of the periodontal ligament on the tension and pressure sides. Understanding the bone response has major implications for dentistry, including a better understanding of the different types of orthodontic tooth movement.
Collapse
Affiliation(s)
- Eliane Hermes Dutra
- Division of Orthodontics, University of Connecticut Health Center, 263 Farmington Avenue, Room No L7056, MC1725, Farmington, CT, 06030, USA
| | - Ravindra Nanda
- Division of Orthodontics, University of Connecticut Health Center, 263 Farmington Avenue, Room No L7056, MC1725, Farmington, CT, 06030, USA
| | - Sumit Yadav
- Division of Orthodontics, University of Connecticut Health Center, 263 Farmington Avenue, Room No L7056, MC1725, Farmington, CT, 06030, USA.
| |
Collapse
|
13
|
Abstract
Tooth movement by orthodontic treatment is characterized by remodeling changes in the periodontal ligament, alveolar bone, and gingiva. A reflection of these phenomenons can be found in the gingival crevicular fluid (GCF) of moving teeth, with significant elevations in the concentrations of its components like, cytokines, neurotransmitters, growth Factors, and a arachidonic acid metabolites. GCF arises at the gingival margin and can be described as a transudate or an exudate. Several studies have focused on the composition of GCF and the changes that occur during orthodontic tooth movement (OTM). GCF component analysis is a non-invasive method for studying the cellular response of the underlying periodontium. Clinically, GCF can be easily collected using platinum loops, filter paper strips, gingival washings, and micropipettes. A number of GCF biomarkers involve in bone remodeling during OTM. The data suggest that knowledge of all the biomarkers present in the GCF that can be used to mark the changes in tooth that is undergoing orthodontic treatment may be of clinical usefulness leading to proper choice of mechanical stress to improve and to shorten treatment time and avoid side effects.
Collapse
Affiliation(s)
- A Anand Kumar
- Department of Orthodontics and Dentofacial Orthopedics, JKK Dental College and Hospital, Komarapalayam, Namakkal, Tamil Nadu, India
| | - K Saravanan
- Department of Orthodontics and Dentofacial Orthopedics, JKK Dental College and Hospital, Komarapalayam, Namakkal, Tamil Nadu, India
| | - K Kohila
- Department of Orthodontics and Dentofacial Orthopedics, JKK Dental College and Hospital, Komarapalayam, Namakkal, Tamil Nadu, India
| | - S Sathesh Kumar
- Department of Orthodontics and Dentofacial Orthopedics, JKK Dental College and Hospital, Komarapalayam, Namakkal, Tamil Nadu, India
| |
Collapse
|
14
|
Zeng M, Kou X, Yang R, Liu D, Wang X, Song Y, Zhang J, Yan Y, Liu F, He D, Gan Y, Zhou Y. Orthodontic Force Induces Systemic Inflammatory Monocyte Responses. J Dent Res 2015; 94:1295-302. [PMID: 26130260 DOI: 10.1177/0022034515592868] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Periodontal inflammation and alveolar bone remodeling during orthodontic tooth movement are considered regional reactions. However, how systemic immune responses are involved in this regional reaction remains unclear. In this study, we explored the systemic effects of orthodontic force by focusing on the mononuclear phagocyte system. Flow cytometric analysis showed that the percentage of inflammatory monocytes, in peripheral blood and in the monocyte reservoir spleen, decreased on days 1 and 3 and then recovered on day 7 after force application. Along with the systemic decrease of inflammatory monocyte percentage, the number of tartrate-resistant acid phosphatase–positive osteoclasts increased in the compression side of the periodontal tissue during orthodontic tooth movement. Systemic transfusion of enhanced green fluorescent protein–labeled inflammatory monocytes showed recruitment of these monocytes to the orthodontic force compression side of periodontal tissues. These monocytes were colocalized with tartrate-resistant acid phosphatase–positive osteoclasts. In vivo and in vitro experiments showed that orthodontic force could upregulate the expression of pivotal monocyte chemokine monocyte chemotactic protein 1 in periodontal tissues or cultured periodontal ligament cells, which may contribute to monocyte recruitment to regional sites. These data suggest that orthodontic force induces systemic immune responses related to inflammatory monocytes and that systemic inflammatory monocytes can be recruited to periodontal tissues by orthodontic force stimulus.
Collapse
Affiliation(s)
- M. Zeng
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - X. Kou
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - R. Yang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - D. Liu
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - X. Wang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - Y. Song
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - J. Zhang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - Y. Yan
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - F. Liu
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - D. He
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - Y. Gan
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Temporomandibular Disorders and Orofacial Pain, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| | - Y. Zhou
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
- Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, P.R. China
| |
Collapse
|
15
|
Accelerated orthodontic tooth movement: Molecular mechanisms. Am J Orthod Dentofacial Orthop 2014; 146:620-32. [DOI: 10.1016/j.ajodo.2014.07.007] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 07/01/2014] [Accepted: 07/01/2014] [Indexed: 12/22/2022]
|
16
|
Effect of cytokines on osteoclast formation and bone resorption during mechanical force loading of the periodontal membrane. ScientificWorldJournal 2014; 2014:617032. [PMID: 24574904 PMCID: PMC3916098 DOI: 10.1155/2014/617032] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 11/20/2013] [Indexed: 01/10/2023] Open
Abstract
Mechanical force loading exerts important effects on the skeleton by controlling bone mass and strength. Several in vivo experimental models evaluating the effects of mechanical loading on bone metabolism have been reported. Orthodontic tooth movement is a useful model for understanding the mechanism of bone remodeling induced by mechanical loading. In a mouse model of orthodontic tooth movement, TNF-α was expressed and osteoclasts appeared on the compressed side of the periodontal ligament. In TNF-receptor-deficient mice, there was less tooth movement and osteoclast numbers were lower than in wild-type mice. These results suggest that osteoclast formation and bone resorption caused by loading forces on the periodontal ligament depend on TNF-α. Several cytokines are expressed in the periodontal ligament during orthodontic tooth movement. Studies have found that inflammatory cytokines such as IL-12 and IFN-γ strongly inhibit osteoclast formation and tooth movement. Blocking macrophage colony-stimulating factor by using anti-c-Fms antibody also inhibited osteoclast formation and tooth movement. In this review we describe and discuss the effect of cytokines in the periodontal ligament on osteoclast formation and bone resorption during mechanical force loading.
Collapse
|
17
|
Gu JH, Tong XS, Chen GH, Liu XZ, Bian JC, Yuan Y, Liu ZP. Regulation of matrix metalloproteinase-9 protein expression by 1α, 25-(OH)₂D₃ during osteoclast differentiation. J Vet Sci 2013; 15:133-40. [PMID: 24136216 PMCID: PMC3973756 DOI: 10.4142/jvs.2014.15.1.133] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 10/06/2013] [Indexed: 01/08/2023] Open
Abstract
To investigate 1α,25-(OH)₂D₃ regulation of matrix metalloproteinase-9 (MMP-9) protein expression during osteoclast formation and differentiation, receptor activator of nuclear factor kB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) were administered to induce the differentiation of RAW264.7 cells into osteoclasts. The cells were incubated with different concentrations of 1α,25-(OH)₂D₃ during culturing, and cell proliferation was measured using the methylthiazol tetrazolium method. Osteoclast formation was confirmed using tartrate-resistant acid phosphatase (TRAP) staining and assessing bone lacunar resorption. MMP-9 protein expression levels were measured with Western blotting. We showed that 1α,25-(OH)₂D₃ inhibited RAW264.7 cell proliferation induced by RANKL and M-CSF, increased the numbers of TRAP-positive osteoclasts and their nuclei, enhanced osteoclast bone resorption, and promoted MMP-9 protein expression in a concentration-dependent manner. These findings indicate that 1α,25-(OH)₂D₃ administered at a physiological relevant concentration promoted osteoclast formation and could regulate osteoclast bone metabolism by increasing MMP-9 protein expression during osteoclast differentiation.
Collapse
Affiliation(s)
- Jian-Hong Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
| | | | | | | | | | | | | |
Collapse
|
18
|
Biomarkers of periodontal tissue remodeling during orthodontic tooth movement in mice and men: overview and clinical relevance. ScientificWorldJournal 2013; 2013:105873. [PMID: 23737704 PMCID: PMC3655650 DOI: 10.1155/2013/105873] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/12/2013] [Indexed: 12/31/2022] Open
Abstract
Biologically active substances are expressed by cells within the periodontium in response to mechanical stimuli from orthodontic appliances. Several possible biomarkers representing biological modifications during specific phenomena as simile-inflammatory process, bone resorption and formation, periodontal ligament changes, and vascular and neural responses are proposed. Citations to potentially published trials were conducted by searching PubMed, Cochrane databases, and scientific textbooks. Additionally, hand searching and contact with experts in the area were undertaken to identify potentially relevant published and unpublished studies. Selection criteria were as follows: animal models involving only mice and rats undergoing orthodontic treatment; collection of gingival crevicular fluid (GCF) as a noninvasively procedure for humans; no other simultaneous treatment that could affect experimental orthodontic movement. The data suggest that knowledge of the remodeling process occurring in periodontal tissues during orthodontic and orthopedic therapies may be a clinical usefulness procedure leading to proper choice of mechanical stress to improve and to shorten the period of treatment, avoiding adverse consequences. The relevance for clinicians of evaluating the rate of some substances as valid biomarkers of periodontal effects during orthodontic movement, by means of two models of study, mice and men, is underlined.
Collapse
|
19
|
Andrade I, Taddei SR, Souza PE. Inflammation and Tooth Movement: The Role of Cytokines, Chemokines, and Growth Factors. Semin Orthod 2012. [DOI: 10.1053/j.sodo.2012.06.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
20
|
|
21
|
Cytokines and VEGF induction in orthodontic movement in animal models. J Biomed Biotechnol 2012; 2012:201689. [PMID: 22665981 PMCID: PMC3361315 DOI: 10.1155/2012/201689] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 03/13/2012] [Accepted: 03/14/2012] [Indexed: 12/29/2022] Open
Abstract
Orthodontics is a branch of dentistry that aims at the resolution of dental malocclusions. The specialist carries out the treatment using intraoral or extraoral orthodontic appliances that require forces of a given load level to obtain a tooth movement in a certain direction in dental arches. Orthodontic tooth movement is dependent on efficient remodeling of periodontal ligament and alveolar bone, correlated with several biological and mechanical responses of the tissues surrounding the teeth. A periodontal ligament placed under pressure will result in bone resorption whereas a periodontal ligament under tension results in bone formation. In the primary stage of the application of orthodontic forces, an acute inflammation occurs in periodontium. Several proinflammatory cytokines are produced by immune-competent cells migrating by means of dilated capillaries. In this paper we summarize, also through the utilization of animal models, the role of some of these molecules, namely, interleukin-1β and vascular endothelial growth factor, that are some proliferation markers of osteoclasts and osteoblasts, and the macrophage colony stimulating factor.
Collapse
|
22
|
Yoshimatsu M, Kitaura H, Fujimura Y, Kohara H, Morita Y, Eguchi T, Yoshida N. Inhibitory effects of IL-12 on experimental tooth movement and root resorption in mice. Arch Oral Biol 2012; 57:36-43. [DOI: 10.1016/j.archoralbio.2011.07.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 06/15/2011] [Accepted: 07/18/2011] [Indexed: 11/26/2022]
|