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Tissue Engineering Supporting Regenerative Strategies to Enhance Clinical Orthodontics and Dentofacial Orthopaedics: A Scoping, Perspective Review. Biomedicines 2023; 11:biomedicines11030795. [PMID: 36979774 PMCID: PMC10045353 DOI: 10.3390/biomedicines11030795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/01/2023] [Accepted: 02/20/2023] [Indexed: 03/08/2023] Open
Abstract
The personalized regenerative therapeutic strategies applicable in the structural and functional repair of maxillofacial/dental defects are expected to extend beyond the limits of what is currently possible in the management of dentofacial anomalies and treating malocclusions. The application of undifferentiated stem cells (SCs), including signaling molecule control and individualized tissue engineering based on targeted therapies, has been proposed to overcome therapeutic limitations and complications associated with treatments for craniofacial defects, including severe orthodontic discrepancies. This scoping, prospective review discusses comprehensively the current knowledge and prospects for improving clinical outcomes by the application of novel cell-required and cell-free regenerative strategies in biomedicine. The existing evidence, although scant, suggests that patients receiving an orthodontic treatment could benefit from precise tissue augmentation, allowing enhancement of tooth movement generated by orthognathic forces; faster, more predictable alignment of dental arches; optimal management of periodontal complications; and prevention of external root resorption. Ultimately, enriching orofacial tissues and “customizing” the repair of congenital/acquired defects in the craniofacial region can be vastly enhanced to provide a positive therapeutic outcome and improve patients’ quality of life.
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Maurya RK, Jayan B, Singh H, Nakra O, Sharma P. Effects of Low-Intensity Pulsed Ultrasound Therapy on the Temporomandibular Joint Complex in Conjunction With a Fixed Functional Appliance: A Prospective 3-Dimensional Cone Beam Computed Tomographic Study. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2019; 38:1661-1676. [PMID: 30393868 DOI: 10.1002/jum.14850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/07/2018] [Accepted: 09/28/2018] [Indexed: 06/08/2023]
Abstract
OBJECTIVES This prospective study aimed to analyze 3-dimensional changes in the temporomandibular joint (TMJ) complex with a synergistic effect of functional jaw orthopedics using a fixed functional appliance and low-intensity pulsed ultrasound (LIPUS) therapy. METHODS Forty patients with skeletal class II malocclusion were randomly assigned to 4 groups (2 control groups and 2 test groups) of 10 patients each. After insertion of the fixed functional appliance, the test group was stimulated with LIPUS therapy in the TMJ region bilaterally for 20 minutes daily for first 10 days and thereafter at least 3 times per week until complete mandibular advancement was achieved. Three-dimensional images obtained with a cone beam computed tomographic scanner were used to analyze the changes in the TMJ complex at the prefunctional stage and after completion of functional appliance therapy. Direct intragroup and intergroup comparisons for different morphometric variables were conducted with the Student t test. RESULTS The 40 patients included 20 male and 20 female patients between the ages of 12 and 16 years (mean age ± SD, 13.2 ± 1.8 years). Both the test groups and the control groups showed statistically significant variable changes in condylar head position and morphometric changes in relation to the joint space analysis (mean differences, -1.000 and -1.080 mm; P < .05). However, no significant differences were found during the intergroup comparisons at the prefunctional and postfunctional stages for the variables examined, except for the measurements of the linear distance of the condyle to the external auditory meatus on both the right and left sides at the prefunctional phase. CONCLUSIONS Low-intensity pulsed ultrasound therapy positively affects the quantum of the joint space, thus proving to be a promising adjunct in enhancing treatment outcomes of functional jaw orthopedics in growing patients with skeletal class II malocclusions.
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Affiliation(s)
- Raj Kumar Maurya
- Department of Orthodontics and Dentofacial Orthopedics, Army Dental Center (Research and Referral), Delhi, India
| | - Balakrishna Jayan
- Department of Orthodontics and Dentofacial Orthopedics, Army Dental Center (Research and Referral), Delhi, India
| | - Harpreet Singh
- Department of Orthodontics and Dentofacial Orthopedics, Employees' State Insurance Corporation Dental College and Hospital, Delhi, India
| | - Oonit Nakra
- Department of Orthodontics and Dentofacial Orthopedics, Army Dental Center (Research and Referral), Delhi, India
| | - Poonam Sharma
- Department of Orthodontics and Dentofacial Orthopedics, Employees' State Insurance Corporation Dental College and Hospital, Delhi, India
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Amuk NG, Baysal A, Coskun R, Kurt G. Effectiveness of incremental vs maximum bite advancement during Herbst appliance therapy in late adolescent and young adult patients. Am J Orthod Dentofacial Orthop 2019; 155:48-56. [DOI: 10.1016/j.ajodo.2018.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/01/2018] [Accepted: 02/01/2018] [Indexed: 10/27/2022]
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Safari S, Mahdian A, Motamedian SR. Applications of stem cells in orthodontics and dentofacial orthopedics: Current trends and future perspectives. World J Stem Cells 2018; 10:66-77. [PMID: 29988866 PMCID: PMC6033713 DOI: 10.4252/wjsc.v10.i6.66] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/19/2018] [Accepted: 05/10/2018] [Indexed: 02/06/2023] Open
Abstract
A simple overview of daily orthodontic practice involves use of brackets, wires and elastomeric modules. However, investigating the underlying effect of orthodontic forces shows various molecular and cellular changes. Also, orthodontics is in close relation with dentofacial orthopedics which involves bone regeneration. In this review current and future applications of stem cells (SCs) in orthodontics and dentofacial orthopedics have been discussed. For craniofacial anomalies, SCs have been applied to regenerate hard tissue (such as treatment of alveolar cleft) and soft tissue (such as treatment of hemifacial macrosomia). Several attempts have been done to reconstruct impaired temporomandibular joint. Also, SCs with or without bone scaffolds and growth factors have been used to regenerate bone following distraction osteogenesis of mandibular bone or maxillary expansion. Current evidence shows that SCs also have potential to be used to regenerate infrabony alveolar defects and move the teeth into regenerated areas. Future application of SCs in orthodontics could involve accelerating tooth movement, regenerating resorbed roots and expanding tooth movement limitations. However, evidence supporting these roles is weak and further studies are required to evaluate the possibility of these ideas.
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Affiliation(s)
- Shiva Safari
- Department of Orthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran 13819, Iran
| | - Arezoo Mahdian
- Department of Orthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran 13819, Iran
| | - Saeed Reza Motamedian
- Department of Orthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran 13819, Iran
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Aras I, Pasaoglu A, Olmez S, Unal I, Tuncer AV, Aras A. Comparison of stepwise vs single-step advancement with the Functional Mandibular Advancer in Class II division 1 treatment. Angle Orthod 2016; 87:82-87. [PMID: 27366817 DOI: 10.2319/032416-241.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE To compare two groups of subjects at the peak of the pubertal growth period treated with the Functional Mandibular Advancer (FMA; Forestadent, Pforzheim, Germany) appliance using either single-step or stepwise mandibular advancement. MATERIALS AND METHODS This study was conducted on 34 Class II division 1 malocclusion subjects at or just before the peak phase of pubertal growth as assessed by hand-wrist radiographs. Subjects were assigned to two groups of mandibular advancement, using matched randomization. Both groups were treated with the FMA. While the mandible was advanced to a super Class I molar relation in the single-step advancement group (SSG), patients in the stepwise mandibular advancement group (SWG) had a 4-mm initial bite advancement and subsequent 2-mm advancements at bimonthly intervals. The material consisted of lateral cephalograms taken before treatment and after 10 months of FMA treatment. Data were analyzed by means paired t-tests and an independent t-test. RESULTS There were statistically significant changes in SNB, Pg horizontal, ANB, Co-Gn, and Co-Go measurements in both groups (P < .001); these changes were greater in the SWG with the exception of Co-Go (P < .05). While significant differences were found in U1-SN, IMPA, L6 horizontal, overjet, and overbite appraisals in each group (P < .001), these changes were comparable (P > .05). CONCLUSION Because of the higher rates of sagittal mandibular skeletal changes, FMA using stepwise advancement of the mandible might be the appliance of choice for treating Class II division 1 malocclusions.
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Doshi UH, Mahindra R. Effective temporomandibular joint growth changes after stepwise and maximum advancement with Twin Block appliance. J World Fed Orthod 2014. [DOI: 10.1016/j.ejwf.2013.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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New therapeutics in promoting and modulating mandibular growth in cases with mandibular hypoplasia. BIOMED RESEARCH INTERNATIONAL 2013; 2013:789679. [PMID: 23819121 PMCID: PMC3681221 DOI: 10.1155/2013/789679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 04/10/2013] [Accepted: 04/18/2013] [Indexed: 01/25/2023]
Abstract
Children with mandibular growth deficiency may develop airway obstruction. The standard treatment of severe airway obstruction involves invasive procedures such as tracheostomy. Mandibular distraction osteogenesis has been proposed in neonates with mandibular deficiency as a treatment option to avoid tracheostomy procedure later in life. Both tracheostomy and distraction osteogenesis procedures suffer from substantial shortcomings including scarring, unpredictability, and surgical complications. Forward jaw positioning appliances have been also used to enhance mandible growth. However, the effectiveness of these appliances is limited and lacks predictability. Current and future approaches to enhance mandibular growth, both experimental and clinical trials, and their effectiveness are presented and discussed.
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Lee RT, Barnes E, DiBiase A, Govender R, Qureshi U. An extended period of functional appliance therapy: a controlled clinical trial comparing the Twin Block and Dynamax appliances. Eur J Orthod 2013; 36:512-21. [PMID: 23291502 DOI: 10.1093/ejo/cjs076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The aim of this clinical trial was to compare the hard- and soft-tissue effects of 15 month full-time functional appliance therapy with Twin Block (TB) and Dynamax (Dx) appliances. The effects on both hard and soft tissue were analysed using cephalograms and three-dimensional optical surface laser scans. One hundred and three subjects with a class II division 1 malocclusion, and a minimum overjet of 7mm were available for analysis following stratified randomization according to gender and age. Data was collected at the start of treatment, 15 month therapy, and after 3 month post-treatment observation. Statistical analysis was conducted using analysis of covariance. The results demonstrated both appliances corrected the overjet with significantly increased skeletal dimensional changes with the TB compared with the Dx with forward movement of pogonion of 5.2mm (TB) and 0.7mm (Dx) P = 0.003. In addition, significant changes occurred particularly in the vertical dimension where there was also an increase in total anterior face height in both groups (TB = 6.4mm, Dx = 5.5mm) and significant (P = 0.003) mandibular length changes were also observed (TB = 7.2mm, Dx = 3.8mm). The cephalometric soft-tissue changes were significantly different between the two appliances at soft-tissue pogonion (TB = 9.8mm, Dx = 4.6mm, P = 0.001). Laser scan three-dimansional changes showed significant difference in the lower labial sulcus region where forward movements were observed (TB = 8.2mm, Dx = 6.2mm; P = 0.04). Overall these changes appear to be greater and more stable than those achieved in a previous 9 month study.
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Affiliation(s)
- Robert T Lee
- *Department of Orthodontics, Bart's & The London NHS Trust, London,
| | - Emma Barnes
- *Department of Orthodontics, Bart's & The London NHS Trust, London
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Schiavoni R. The Herbst appliance updated. Prog Orthod 2011; 12:149-60. [PMID: 22074840 DOI: 10.1016/j.pio.2011.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 06/09/2011] [Accepted: 06/13/2011] [Indexed: 11/27/2022] Open
Abstract
The aim of this paper is to analyze the evolution that the Herbst appliance has experienced in the last 30 years. In particular the different designs proposed for the Herbst appliance are examined and the related differences in clinical management, indications, and treatment effects are also illustrated. The two major challenges in the clinical management of the Herbst appliance are represented by the choice of the type of stabilization and by the control of the proclination of the lower incisors. The use of acrylic splints presents a set of relevant advantages: the construction technique is simple, the appliance can be worn easily by the patients, and the height of the splint can be adjusted to the growth pattern. Moreover, the acrylic splint Herbst can be used to reposition the mandible in cases with temporomandibular disorders. As for the proclination of the lower incisors, an accurate assessment of the neuromuscular pattern of the individual patient before treatment can provide the clinician with reliable criteria to evaluate the risk for incisor proclination during Herbst therapy.
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Austin DF, Chaiyongsirisern A, Yang Y, Wong RWK, Rabie ABM. A protocol for improved stability with Herbst appliance treatment for adults. Prog Orthod 2010; 11:151-6. [PMID: 20974452 DOI: 10.1016/j.pio.2010.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 09/15/2010] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVE To present a treatment protocol for improved stability with Herbst appliance treatment in Class II adult cases. MATERIALS AND METHODS Sixteen Class II adults were treated at the University of Hong Kong with two phase treatment. The treatment protocol which leads to good stability was presented. RESULTS The protocol leading to stable correction of overjet, molar relationship and enhanced forward positioning of the mandible involved 12 months Herbst appliance treatment with stepwise advancement followed by fixed appliance. CONCLUSIONS The long term stability of Herbst appliance treatment is influenced by the treatment protocol employed. Based on the stability of the adult group in the present study, it is recommended to treat for 12 months in a step-wise manner for mandibular advancement with over correction.
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Affiliation(s)
- David F Austin
- Faculty of Dentistry, the University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong
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Kim HS, Kim HY, Heo SS, Kang KH, Kim SC. Expression of nitric oxide synthases in the mandibular condyle of anterior repositioned rat mandibles. ACTA ACUST UNITED AC 2010. [DOI: 10.4041/kjod.2010.40.4.239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Ho-Young Kim
- Graduate Student, Department of Orthodontics, School of Dentistry, Wonkwang University, Korea
| | - Sung-Su Heo
- Resident, Department of Orthodontics, School of Dentistry, Wonkwang University, Korea
| | - Kyang-Hwa Kang
- Associate Professor, Department of Orthodontics, School of Dentistry, Wonkwang University, Korea
| | - Sang-Cheol Kim
- Professor, Department of Orthodontics, School of Dentistry, Wonkwang University, Korea
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Wadhawan N, Kumar S, Kharbanda OP, Duggal R, Sharma R. Temporomandibular joint adaptations following two-phase therapy: an MRI study. Orthod Craniofac Res 2009; 11:235-50. [PMID: 18950321 DOI: 10.1111/j.1601-6343.2008.00436.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To document the alterations within the condyle-glenoid fossa (C-GF) complex and the positional changes of the glenoid fossa in the cranium after removable functional appliance therapy and after the completion of fixed appliance therapy. SETTING AND SAMPLE The Department of Orthodontics, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India. The study sample consisted of 12 growing children (eight girls and four boys) between 10 and 14 years of age with skeletal Class II division 1 malocclusion selected on well defined criteria. MATERIALS AND METHODS All patients were treated with either the Twin Block or the Bionator appliance followed by fixed appliances. Mean total treatment duration was 28 months. The changes in and around the C-GF complex were evaluated using MRI at pre-treatment stage, after functional appliance therapy and at the completion of fixed mechanotherapy. RESULTS Forward condylar position within the glenoid fossa and articular disc retrusion with respect to the condylar head were statistically significant after functional appliance therapy. However, the condyles had a relatively concentric position within the glenoid fossa, while the articular disc resumed its pre-treatment position at the end of the treatment. Linear measurements from the centre of the external auditory meatus to the post-glenoid spine revealed a 1.3-mm forward relocation of the post-glenoid spine along the Frankfurt Horizontal plane. CONCLUSIONS Forward relocation of the C-GF complex seems to be one of the mechanisms of action of functional appliances, while the internal anatomic arrangement within the temporomandibular joint (TMJ) complex normalizes to its pre-treatment position.
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Affiliation(s)
- N Wadhawan
- Center for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India
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Macroscopic and microscopic aspects of the temporomandibular joint related to its clinical implication. Micron 2008; 39:852-8. [DOI: 10.1016/j.micron.2007.12.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2007] [Revised: 12/09/2007] [Accepted: 12/14/2007] [Indexed: 11/17/2022]
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Rabie ABM, Al-Kalaly A. Does the degree of advancement during functional appliance therapy matter? Eur J Orthod 2008; 30:274-82. [PMID: 18343894 PMCID: PMC2422860 DOI: 10.1093/ejo/cjm129] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The aim of this study was to assess the effect of varied degrees of mandibular advancement on condylar growth. Three hundred and thirty five 35-day-old female Sprague-Dawley rats were randomly divided into 10 experimental groups (n = 10) and five control groups (n = 5) for analysis of new bone formation and 10 experimental groups (n = 14) and five control groups (n = 14) for molecular analysis. The experimental animals were fitted with bite-jumping appliance to advance the mandible 2 and 4 mm. The rats were sacrificed on days 3, 7, 14, 21, and 30. A computer-assisted image analysing system was used to assess the quantity of new condylar bone formation. Molecular analysis utilizing real-time reverse transcription-polymerase chain reaction was used to assess the different levels of mRNA expression of different growth markers in the condyle. One-way analysis of variance (ANOVA), with a Bonferroni multiple comparison test, showed significantly more newly formed bone in the 4 mm group compared with the 2 mm and control groups on days 21 and 30 (P < 0.05). Most of the examined growth markers demonstrated a significant increase during the 4 mm advancement (P < 0.05). Indian hedgehog (Ihh) mRNA showed a 7- and 5-fold change, parathyroid hormone-related peptide (PTHrP) a 5.2- and 3-fold change and type II collagen a 9.6- and 3.7-fold change in the 4 and 2 mm advancement groups, respectively. Varied degrees of mandibular advancement result in different quantities of new bone formation and levels of expression of growth members: Ihh, PTHrP, and type II collagen.
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Affiliation(s)
- A Bakr M Rabie
- Department of Orthodontics, Faculty of Dentistry, The University of Hong Kong, SAR, China.
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Li QF, Rabie ABM. A new approach to control condylar growth by regulating angiogenesis. Arch Oral Biol 2007; 52:1009-17. [PMID: 17640614 DOI: 10.1016/j.archoralbio.2007.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 05/04/2007] [Accepted: 05/24/2007] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To provide a comprehensive review of the mechanisms of growth of mandibular condyle, the roles of angiogenesis enhancers and inhibitors during endochondral ossification in mandibular condyle and newly developed delivery methods for local gene delivery that may represent strategies to regulate condylar growth. DESIGN Narrative review. RESULTS Angiogenesis is the crucial step in mandibular condylar growth for it regulates the transformation from cartilage to bone. Angiognesis enhancers, especially VEGF and FGF, play important roles in the process of new blood lumen formation and invasion. On the other hand, angiostatin and endostatin inhibit angiogenesis by targeting endothelial cells and several signal cascades. Delivery methods such as liposomes, stem cells and virus vectors have been studied. Recombinant AAV-mediated gene therapy is considered as one of the most promising strategies of condylar growth management. CONCLUSION AAV-mediated gene therapy using VEGF or angiogenesis inhibitor will be a promising way to regulate condylar growth at an early stage.
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Affiliation(s)
- Q F Li
- The Biomedical and Tissue Engineering Group, Department of Orthodontics, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong SAR, China
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Tagliaro ML, Rassi Guimarães ML, Pereira Padilha DM, Callegari-Jacques SM, Jeckel-Neto EA. Mandibular advancement and morphological changes in the mandibles of female mice of different ages. Exp Gerontol 2006; 41:1157-64. [PMID: 16979863 DOI: 10.1016/j.exger.2006.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 07/31/2006] [Accepted: 08/02/2006] [Indexed: 11/25/2022]
Abstract
Mandibular advancement (MA) by means of functional orthopedic techniques is currently used in young patients to stimulate mandibular growth. The aim of this study was to evaluate the morphological changes in the mandibles of 2-, 7-, and 16-month-old female mice after MA. Every 3 days during 1 month, the lower incisors were trimmed by 1mm to induce protrusion when the animal was feeding. The left mandibles of the 30 experimental and 28 control individuals were subsequently dissected and digital images were obtained to analyze nine linear/angular measurements. The condylar microstructure was also analyzed by scanning electron microscopy (SEM). The linear/angular measurements showed a growth response in different mandibular regions in 2- and 16-month-old individuals. SEM showed that, in the 7-month-old mice, the condylar cartilage had regenerated in the treated individuals but not in the controls. The results suggest that MA produces mandibular growth in 2- and 16-month-old female mice. Although there was no mandibular growth in 7-month-old mice, regeneration of the condylar cartilage was detected, thus demonstrating that different responses to the MA stimulus occur in female mice of different ages.
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Affiliation(s)
- Maria Luisa Tagliaro
- Biomedical Gerontology Post-graduate Program, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre 90035-051, Brazil.
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Wong L, Hägg U, Wong G. Correction of extreme overjet in 2 phases. Am J Orthod Dentofacial Orthop 2006; 130:540-8. [PMID: 17045156 DOI: 10.1016/j.ajodo.2005.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2004] [Revised: 05/04/2005] [Accepted: 06/23/2005] [Indexed: 11/26/2022]
Abstract
This case report describes the treatment of a 12-year-old Chinese boy with a Class II skeletal profile, an extreme overjet, and a retrusive mandible. The patient was teased at school because of his appearance, and he was experiencing negative psychosocial impacts, including shyness and falling grades. Orthodontic treatment had a positive psychosocial impact on his life over a period of 10 years. The advantages of using functional appliances are highlighted in this report.
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Affiliation(s)
- Louise Wong
- Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, China
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Guan G, Shi S, Kramer PR. Role of Adult Stem Cells in Craniofacial Growth and Repair. Semin Orthod 2005. [DOI: 10.1053/j.sodo.2005.07.007] [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]
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