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Abello EH, Nguyen TV, Dilley KK, Hong D, Kim JS, Nair PS, Bitner BF, Jia W, Wong BJF. Temperature Profile Measurement From Radiofrequency Nasal Airway Reshaping Device. Laryngoscope 2024; 134:1063-1070. [PMID: 37594207 DOI: 10.1002/lary.30942] [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: 01/25/2023] [Revised: 06/17/2023] [Accepted: 07/19/2023] [Indexed: 08/19/2023]
Abstract
OBJECTIVE Nasal airway obstruction (NAO) is caused by various disorders including nasal valve collapse (NVC). A bipolar radiofrequency (RF) device (VivAer®, Aerin Medical, Sunnyvale, CA) has been used to treat NAO through RF heat generation to the upper lateral cartilage (ULC). The purpose of this study is to measure temperature elevations in nasal tissue, using infrared (IR) radiometry to map the spatial and temporal evolution of temperature. STUDY DESIGN Experimental and computational. METHODS Composite porcine nasal septum was harvested and sectioned (1 mm and 2 mm). The device was used to heat the cartilage in composite porcine septum. An IR camera (FLIR® ExaminIR, Teledyne, Wilsonville, OR) was used to image temperature on the back surface of the specimen. These data were incorporated into a heat transfer finite element model that also calculated tissue damage using Arrhenius rate process. RESULTS IR temperature imaging showed peak back surface temperatures of 49.57°C and 42.21°C in 1 and 2 mm thick septums respectively. Temperature maps were generated demonstrating the temporal and spatial evolution of temperature. A finite element model generated temperature profiles with respect to time and depth. Rate process models using Arrhenius coefficients showed 30% chondrocyte death at 1 mm depth after 18 s of RF treatment. CONCLUSION The use of this device creates a thermal profile that may result in thermal injury to cartilage. Computational modeling suggests chondrocyte death extending as deep as 1.4 mm below the treatment surface. Further studies should be performed to improve dosimetry and optimize the heating process to reduce potential injury. Laryngoscope, 134:1063-1070, 2024.
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Affiliation(s)
- Eric H Abello
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
- Department of Otolaryngology - Head and Neck Surgery, University of California - Irvine Medical Center, Orange, California, USA
| | | | - Katelyn K Dilley
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
| | - Donggyoon Hong
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
| | - Justin S Kim
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
| | - Pranav S Nair
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
| | - Benjamin F Bitner
- Department of Otolaryngology - Head and Neck Surgery, University of California - Irvine Medical Center, Orange, California, USA
| | - Wangcun Jia
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
| | - Brian J F Wong
- Beckman Laser Institute and Medical Clinic, Irvine, California, USA
- Department of Otolaryngology - Head and Neck Surgery, University of California - Irvine Medical Center, Orange, California, USA
- Department of Biomedical Engineering, Henry Samueli School of Engineering, Irvine, California, USA
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Casale M, Moffa A, Giorgi L, Pierri M, Lugo R, Jacobowitz O, Baptista P. Could the use of a new novel bipolar radiofrequency device (Aerin) improve nasal valve collapse? A systematic review and meta-analysis. J Otolaryngol Head Neck Surg 2023; 52:42. [PMID: 37349806 DOI: 10.1186/s40463-023-00644-7] [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: 07/05/2022] [Accepted: 04/22/2023] [Indexed: 06/24/2023] Open
Abstract
BACKGROUND Surgical treatment for nasal obstruction caused by nasal valve collapse requires a significant recovery period and risks of complications, while nasal dilators are uncomfortable. Recently, radiofrequency treatment of lateral walls has been used under local anesthesia as an office base surgery. This work aims to assess the efficacy of a new radiofrequency device, the Vivaer™ System (Aerin Medical, Sunnyvale, CA), to treat nasal obstruction through a systematic review and meta-analysis. METHODS Two researchers independently reviewed the literature up to December 2021. Studies on patients seeking treatment for nasal obstruction due to nasal valve collapse were included in the analysis. RESULTS Four studies (218 patients) met the inclusion criteria and treated the nasal valve regions bilaterally with the Aerin Medical Vivaer™ System. After the treatment, the NOSE score was reduced at three months postoperatively. Minor adverse events were reported in the included studies, and two showed no complications. None of the studies reported changes in the external appearance of the nose. CONCLUSION The radiofrequency treatment using the Vivaer device can be useful for treating nasal valve collapse, improving significantly subjective breathing symptom scores. Further studies on a large scale are needed to confirm these results.
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Affiliation(s)
- Manuele Casale
- School of Medicine, Università Campus Bio-Medico di Roma, Via Álvaro del Portillo, 21, 00128, Rome, RM, Italy
- Unit of Integrated Therapies in Otolaryngology, Fondazione Policlinico Universitario Campus Bio-Medico, Rome, Italy
| | - Antonio Moffa
- School of Medicine, Università Campus Bio-Medico di Roma, Via Álvaro del Portillo, 21, 00128, Rome, RM, Italy.
- Unit of Integrated Therapies in Otolaryngology, Fondazione Policlinico Universitario Campus Bio-Medico, Rome, Italy.
| | - Lucrezia Giorgi
- Unit of Integrated Therapies in Otolaryngology, Fondazione Policlinico Universitario Campus Bio-Medico, Rome, Italy
| | - Michelangelo Pierri
- School of Medicine, Università Campus Bio-Medico di Roma, Via Álvaro del Portillo, 21, 00128, Rome, RM, Italy
- Unit of Integrated Therapies in Otolaryngology, Fondazione Policlinico Universitario Campus Bio-Medico, Rome, Italy
| | - Rodolfo Lugo
- Department of Otolaryngology Head and Neck Surgery, Hospital San José, 64718, Monterrey, Mexico
| | | | - Peter Baptista
- Department of Otorhinolaryngology, Clínica Universidad de Navarra, Pamplona, Spain
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Sivam S, Jones E. Minimally invasive nasal valve treatment. Facial Plast Surg 2022; 38:353-358. [PMID: 35545120 DOI: 10.1055/a-1849-5594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Nasal valve insufficiency can be addressed using endonasal and open structure surgical techniques. However, some patients may prefer or be better suited for minimally invasive techniques that allow for more expedient treatment in the clinical setting. Techniques include internal dilators, external dilators, suture suspension, lateral wall implants, and radiofrequency remodeling. Understanding the indications for each technique as well as the available evidence can help facial plastic surgeons assess the role of incorporating these techniques into the care of patients with nasal valve insufficiency.
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Affiliation(s)
- Sunthosh Sivam
- Otolaryngology, Baylor College of Medicine, Bellaire, United States
| | - Evan Jones
- Otolaryngology, Baylor College of Medicine, Houston, United States
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Wu Z, Krebs JP, Spector BM, Otto BA, Zhao K, Farag AA. Regional Peak Mucosal Cooling Predicts Radiofrequency Treatment Outcomes of Nasal Valve Obstruction. Laryngoscope 2020; 131:E1760-E1769. [PMID: 33140876 DOI: 10.1002/lary.29223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 01/27/2023]
Abstract
OBJECTIVES/HYPOTHESIS Low energy radiofrequency may offer effective treatment for narrow or obstructed nasal valve, yet its precise mechanism is not fully understood. STUDY DESIGN Prospective, nonrandomized, case series. METHODS Twenty prospective patients with internal nasal valve obstruction underwent office-based Vivaer treatment (Aerin Medical, Inc) under local anesthesia. Computational fluid dynamics (CFD) models were constructed based on the pre- and 90 days post-procedure computed tomography (CT) scans to identify salient changes in nasal airflow parameters. RESULTS Patients' Nasal Obstruction Symptom Evaluation score (NOSE: pre-treatment 78.89 ± 11.57; post-treatment 31.39 ± 18.30, P = 5e-7) and Visual Analog Scale of nasal obstruction (VAS: pre-treatment 6.01 ± 1.83; post-treatment 3.44 ± 2.11, P = 1e-4) improved significantly at 90 days after the minimally invasive approach. Nasal airway volume in the treatment area increased ~7% 90 days post-treatment (pre-treatment 5.97 ± 1.20, post-treatment 6.38 ± 1.50 cm3 , P = .018), yet there were no statistically significant changes in the measured peak nasal inspiratory flowrate (PNIF, pre-treatment: 60.16 ± 34.49; post-treatment: 72.38 ± 43.66 ml/s; P = .13) and CFD computed nasal resistance (pre-treatment: 0.096 ± 0.065; post-treatment: 0.075 ± 0.026 Pa/(ml/s); P = .063). As validation, PNIF correlated significantly with nasal resistance (r = 0.47, P = .004). Among all the variables, only the peak mucosal cooling posterior to the nasal vestibule significantly correlated with the NOSE at baseline (r = -0.531, P = .023) and with post-treatment improvement (r = 0.659, P = .003). CONCLUSION Minimal remodeling of the nasal valve (7% in this study) may have a profound effect on perceived nasal obstruction, despite little effect on nasal resistance, or PNIF. The results corroborated our previous findings that subjective relief of nasal obstruction correlates with regional mucosal cooling rather than nasal resistance or peak flow rate, a potential target for future effective, personalized therapeutic approaches. LEVEL OF EVIDENCE 4 Laryngoscope, 131:E1760-E1769, 2021.
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Affiliation(s)
- Zhenxing Wu
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
| | - Jillian P Krebs
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
| | - Barak M Spector
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
| | - Bradley A Otto
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
| | - Kai Zhao
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
| | - Alexander A Farag
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, Ohio, U.S.A
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Guo F, Yu X, Sun Z, Pan B, Jiang H. [Preliminary study on microdissection needle-assisted ear cartilage reshaping in vivo rabbit models]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2019; 33:601-605. [PMID: 31090355 DOI: 10.7507/1002-1892.201807032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Objective To preliminarily investigate morghological changes of rabbits reshaping ear cartilage assisted by microdissection needle and explore feasibility of new therapy for ear deformity. Methods The bilateral ears of 5 male New Zealand rabbits (aged, 5-6 months) were fixed maintaining the curvature and randomly divided into 2 groups (5 ears in each group). The ears were stimulated by microdissection needle in experimental group and were not treated with stimulation in control group. The skin reaction in the experimental group was observed immediately and at 4 weeks after stimulation. Then, the fixtures were removed at 4 weeks, and the shapes of the ears were observed. The cartilages were harvested from the ears to examined morphological changes after HE staining, and measured the chondrocyte layer thickness. Results All rabbits survived until the end of the experiment. The skin has healed completely after 4 weeks in experimental group. After removing fixtures, the ears in the two groups all maintained certain forms momentarily; while 24 hours later, the ears in the control group mostly recovered original form, and the ears in the experimental group still maintained certain molding form until 8 weeks. HE staining showed there were smooth cartilage and uniform distribution of cells in the control group; the matrix staining was basically consistent; and the skin was normal appearance with epidermis, dermis, and cartilage of normal aspect. But the proliferation of chondrocyte with more layers of cells were observed in the experimental group. In addition, there were degeneration and injury of cartilage cells and connective tissue with necrotic cells and inflammatory cells at needle insertion sites. The chondrocyte layer thickness was (385.714±2.027) μm in the control group and (1 594.732±1.872) μm in the experimental group, there was significant difference between the two groups ( t=-759.059, P=0.000). Conclusion Rabbit ear cartilage can be effectively reshaped by microdissection needle. Proliferation of chondrocyte and changes in matrix can be found during the reshaping process.
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Affiliation(s)
- Fengfeng Guo
- The Seventh Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144, P.R.China
| | - Xiaobo Yu
- The Seventh Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144, P.R.China
| | - Zhongyang Sun
- Department of Plastic Surgery, Beijing Hospital, Beijing, 100730, P.R.China
| | - Bo Pan
- The Seventh Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144, P.R.China
| | - Haiyue Jiang
- The Seventh Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144,
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Jacobowitz O, Driver M, Ephrat M. In-office treatment of nasal valve obstruction using a novel, bipolar radiofrequency device. Laryngoscope Investig Otolaryngol 2019; 4:211-217. [PMID: 31024989 PMCID: PMC6476263 DOI: 10.1002/lio2.247] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/26/2018] [Accepted: 01/03/2019] [Indexed: 11/23/2022] Open
Abstract
Objectives To assess the safety and effectiveness of in‐office bipolar radiofrequency treatment of nasal valve obstruction Study Design Prospective, nonrandomized, multicenter case series Methods Adult patients with a Nasal Obstruction Symptom Evaluation scale (NOSE) score ≥60 were selected. Patients were clinically diagnosed with dynamic or static internal nasal valve obstruction as primary or significant contributor to obstruction and were required to have a positive response to nasal mechanical dilators or lateralization maneuvers. Bilateral radio‐frequency treatment was applied intranasally using a novel device, under local anesthesia in a single session. Safety and tolerance were assessed by event reporting, inspection, and Visual Analogue Scale (VAS) for pain. Efficacy was determined using the NOSE score and patient‐reported satisfaction survey at 26 weeks. Results Fifty patients were treated. No device or procedure‐related serious adverse events occurred. Soreness, edema, and crusting resolved by 1 month. The mean baseline NOSE score was 79.9 (SD 10.8, range 60–100), and all had severe or extreme obstruction. At 26 weeks, mean NOSE score was 69% lower at 24.7 (P < .0001) with 95% two‐sided confidence intervals 48.5 to 61.1 for decrease. The decrease in NOSE score did not differ significantly between patients who did or did not have prior nasal surgery. Patient satisfaction mean by survey was 8.2 of 10. Conclusion In office treatment of internal nasal valve obstruction using a bipolar radiofrequency device is safe and well‐tolerated. Nasal obstruction, as assessed using the NOSE questionnaire at 26 weeks, was markedly improved with high patient satisfaction. Level of Evidence 2b, prospective cohort
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Affiliation(s)
| | - Mark Driver
- ENT and Allergy Associates New York New York U.S.A
| | - Moshe Ephrat
- ENT and Allergy Associates New York New York U.S.A
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Han G, Eriten M. Effect of relaxation-dependent adhesion on pre-sliding response of cartilage. ROYAL SOCIETY OPEN SCIENCE 2018; 5:172051. [PMID: 29892390 PMCID: PMC5990745 DOI: 10.1098/rsos.172051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
Possible links between adhesive properties and the pre-sliding (static) friction response of cartilage are not fully understood in the literature. The aims of this study are to investigate the relation between adhesion and relaxation time in articular cartilage, and the effect of relaxation-dependent adhesion on the pre-sliding response of cartilage. Adhesion tests were performed to evaluate the work of adhesion of cartilage at different relaxation times. Friction tests were conducted to identify the pre-sliding friction response of cartilage at relaxation times corresponding to adhesion tests. The pre-sliding friction response of cartilage was systematically linked to the work of adhesion and contact conditions by a slip-based failure model. It was found that the work of adhesion increases with relaxation time. Also, the work of adhesion is linearly correlated to the resistance to slip-based failure. In addition, as the work of adhesion increases, the adhered (stick) area at the moment of failure increases, and the propagation rate of the annular slip (crack) area towards its centre increases. These findings offer a mechanistic explanation of the pre-sliding friction behaviour and stick-slip response of soft hydrated interfaces such as articular cartilage and hydrogels. In addition, the linear correlation between adhesion and threshold to slip-based failure enables estimation of the adhesive strength of such interfaces directly from the pre-sliding friction response (e.g. shear wave elastography).
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Affiliation(s)
- Guebum Han
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
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Yau AYY, Manuel C, Hussain SF, Protsenko DE, Wong BJF. In vivo needle-based electromechanical reshaping of pinnae: New Zealand White rabbit model. JAMA FACIAL PLAST SU 2015; 16:245-52. [PMID: 24854476 DOI: 10.1001/jamafacial.2014.85] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Electromechanical reshaping (EMR) is a low-cost, needle-based, and simple means to shape cartilage tissue without the use of scalpels, sutures, or heat that can potentially be used in an outpatient setting to perform otoplasty. OBJECTIVES To demonstrate that EMR can alter the shape of intact pinnae in an in vivo animal model and to show that the amount of shape change and the limited cell injury are proportional to the dosimetry. DESIGN, SETTING, AND SPECIMENS In an academic research setting, intact ears of 18 New Zealand white rabbits underwent EMR using 6 different dosimetry parameters (4 V for 5 minutes, 4 V for 4 minutes, 5 V for 3 minutes, 5 V for 4 minutes, 6 V for 2 minutes, and 6 V for 3 minutes). A custom acrylic jig with 2 rows of platinum needle electrodes was used to bend ears at the middle of the pinna and to perform EMR. Treatment was repeated twice per pinna, in proximal and distal locations. Control pinnae were not subjected to current application when being bent and perforated within the jig. Pinnae were splinted for 3 months along the region of the bend using soft silicon sheeting and a cotton bolster. MAIN OUTCOMES AND MEASURES The ears were harvested the day after splints were removed and before euthanasia. Photographs of ears were obtained, and bend angles were measured. Tissue was sectioned for histologic examination and confocal microscopy to assess changes to microscopic structure and cellular viability. RESULTS Treated pinnae were bent more and retained shape better than control pinnae. The mean (SD) bend angles in the 7 dosimetry groups were 55° (35°) for the control, 60° (15°) for 4 V for 4 minutes, 118° (15°) for 4 V for 5 minutes, 88° (26°) for 5 V for 3 minutes, 80° (17°) for 5 V for 4 minutes, 117° (21°) for 6 V for 2 minutes, and 125° (18°) for 6 V for 3 minutes. Shape change was proportional to electrical charge transfer, which increased with voltage and application time. Hematoxylin-eosin staining of the pinnae identified localized areas of cell injury and fibrosis in the cartilage and in the surrounding soft tissue where the needle electrodes were inserted. This circumferential zone of injury (range, 1.5-2.5 mm) corresponded to dead cells on cell viability assay, and the diameter of this region increased with total electrical charge transfer to a maximum of 2.5 mm at 6 V for 3 minutes. CONCLUSIONS AND RELEVANCE Electromechanical reshaping produced shape change in intact pinnae of rabbits in this expanded in vivo study. A short application of 4 to 6 V can achieve adequate reshaping of the pinnae. Tissue injury around the electrodes increases with the amount of total current transferred into the tissue and is modest in spatial distribution. This study is a critical step toward evaluation of EMR in clinical trials. LEVEL OF EVIDENCE NA.
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Affiliation(s)
- Amy Y Y Yau
- Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine
| | - Cyrus Manuel
- Beckman Laser Institute, University of California, Irvine
| | - Syed F Hussain
- Department of Biomedical Engineering, University of California, Irvine
| | | | - Brian J F Wong
- Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine2Beckman Laser Institute, University of California, Irvine3Department of Biomedical Engineering, University of California, Irvine
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Al Dayeh AA, Herring SW. Compressive and tensile mechanical properties of the porcine nasal septum. J Biomech 2014; 47:154-61. [PMID: 24268797 PMCID: PMC3910320 DOI: 10.1016/j.jbiomech.2013.09.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 08/28/2013] [Accepted: 09/20/2013] [Indexed: 11/21/2022]
Abstract
The expanding nasal septal cartilage is believed to create a force that powers midfacial growth. In addition, the nasal septum is postulated to act as a mechanical strut that prevents the structural collapse of the face under masticatory loads. Both roles imply that the septum is subject to complex biomechanical loads during growth and mastication. The purpose of this study was to measure the mechanical properties of the nasal septum to determine (1) whether the cartilage is mechanically capable of playing an active role in midfacial growth and in maintaining facial structural integrity and (2) if regional variation in mechanical properties is present that could support any of the postulated loading regimens. Porcine septal samples were loaded along the horizontal or vertical axes in compression and tension, using different loading rates that approximate the in vivo situation. Samples were loaded in random order to predefined strain points (2-10%) and strain was held for 30 or 120 seconds while relaxation stress was measured. Subsequently, samples were loaded until failure. Stiffness, relaxation stress and ultimate stress and strain were recorded. Results showed that the septum was stiffer, stronger and displayed a greater drop in relaxation stress in compression compared to tension. Under compression, the septum displayed non-linear behavior with greater stiffness and stress relaxation under faster loading rates and higher strain levels. Under tension, stiffness was not affected by strain level. Although regional variation was present, it did not strongly support any of the suggested loading patterns. Overall, results suggest that the septum might be mechanically capable of playing an active role in midfacial growth as evidenced by increased compressive residual stress with decreased loading rates. However, the low stiffness of the septum compared to surrounding bone does not support a strut role. The relatively low stiffness combined with high stress relaxation under fast loading rates suggests that the nasal septum is a stress dampener, helping to absorb and dissipate loads generated during mastication.
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Affiliation(s)
- Ayman A Al Dayeh
- Orthodontist, Odessa Dental Solution, 2470 E 11th street, 79776 Midland/Odessa, TX, United States.
| | - Susan W Herring
- Departments of Orthodontics and Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States
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Colombo V, Cadová M, Gallo LM. Mechanical behavior of bovine nasal cartilage under static and dynamic loading. J Biomech 2013; 46:2137-44. [PMID: 23915577 DOI: 10.1016/j.jbiomech.2013.07.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 07/02/2013] [Accepted: 07/04/2013] [Indexed: 11/27/2022]
Abstract
Abnormal mechanical loading may trigger cartilage degeneration associated with osteoarthritis. Tissue response to load has been the subject of several in vitro studies. However, simple stimuli were often applied, not fully mimicking the complex in vivo conditions. Therefore, a rolling/plowing explant test system (RPETS) was developed to replicate the combined in vivo loading patterns. In this work we investigated the mechanical behavior of bovine nasal septum (BNS) cartilage, selected as tissue approximation for experiments with RPETS, under static and dynamic loading. Biphasic material properties were determined and compared with those of other cartilaginous tissues. Furthermore, dynamic loading in plowing modality was performed to determine dynamic response and experimental results were compared with analytical models and Finite Elements (FE) computations. Results showed that BNS cartilage can be modeled as a biphasic material with Young's modulus E=2.03 ± 0.7 MPa, aggregate modulus HA=2.35 ± 0.7 MPa, Poisson's ratio ν=0.24 ± 0.07, and constant hydraulic permeability k0=3.0 ± 1.3 × 10(-15)m(4)(Ns)(-1). Furthermore, dynamic analysis showed that plowing induces macroscopic reactions in the tissue, proportionally to the applied loading force. The comparison among analytical, FE analysis and experimental results showed that predicted tangential forces and sample deformation lay in the range of variation of experimental results for one specific experimental condition. In conclusion, mechanical properties of BNS cartilage under both static and dynamic compression were assessed, showing that this tissue behave as a biphasic material and has a viscoelastic response to dynamic forces.
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Affiliation(s)
- Vera Colombo
- Clinic of Masticatory Disorders, Removable Prosthodontics, Geriatric and Special Care Dentistry, Center of Dental Medicine, University of Zurich, Switzerland.
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