In JoVE (1)
Other Publications (1)
Articles by Andrew T. Jang in JoVE
In situ Trykk Lasting og korrelative Noninvasive Imaging av Bone-periodontal ligament-tann fibrøs Joint Andrew T. Jang1, Jeremy D. Lin1, Youngho Seo2, Sergey Etchin3, Arno Merkle3, Kevin Fahey3, Sunita P. Ho1 1Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California San Francisco, 2Department of Radiology and Biomedical Imaging, University of California San Francisco, 3Xradia Inc. I denne studien, vil bruk av en in situ lademekanisme kombinert med mikro-røntgen-computertomografi for fibrøse felles biomechanics bli diskutert. Eksperimentelle leselig identifiserbare med en samlet endring i felles biomekanikk vil inneholde: 1) reaksjonær kraft vs fortrengning, dvs. tann forskyvning innenfor kjeve kontakten og sin reaksjonære respons til lasting, 2) tredimensjonale (3D) romlig konfigurasjon og morphometrics, dvs. geometrisk Forholdet av tannen med den alveolar-kontakten, og 3) forandringer i avlesninger 1 og 2 på grunn av en endring i lastende akse, dvs. konsentriske eller eksentriske belastninger.
Other articles by Andrew T. Jang on PubMed
Biomechanics of a Bone-periodontal Ligament-tooth Fibrous Joint Journal of Biomechanics. Feb, 2013 | Pubmed ID: 23219279 This study investigates bone-tooth association under compression to identify strain amplified sites within the bone-periodontal ligament (PDL)-tooth fibrous joint. Our results indicate that the biomechanical response of the joint is due to a combinatorial response of the constitutive properties of organic, inorganic, and fluid components. Second maxillary molars within intact maxillae (N=8) of 5-month-old rats were loaded with a μ-XCT-compatible in situ loading device at various permutations of displacement rates (0.2, 0.5, 1.0, 1.5, 2.0 mm/min) and peak reactionary load responses (5, 10, 15, 20 N). Results indicated a nonlinear biomechanical response of the joint, in which the observed reactionary load rates were directly proportional to displacement rates (velocities). No significant differences in peak reactionary load rates at a displacement rate of 0.2mm/min were observed. However, for displacement rates greater than 0.2mm/min, an increasing trend in reactionary rate was observed for every peak reactionary load with significant increases at 2.0mm/min. Regardless of displacement rates, two distinct behaviors were identified with stiffness (S) and reactionary load rate (LR) values at a peak load of 5 N (S(5 N)=290-523 N/mm) being significantly lower than those at 10 N (LR(5 N)=1-10 N/s) and higher (S(10 N-20 N)=380-684 N/mm; LR(10 N-20 N)=1-19 N/s). Digital image correlation revealed the possibility of a screw-like motion of the tooth into the PDL-space, i.e., predominant vertical displacement of 35 μm at 5 N, followed by a slight increase to 40 μm at 10 N and 50 μm at 20 N of the tooth and potential tooth rotation at loads above 10 N. Narrowed and widened PDL spaces as a result of tooth displacement indicated areas of increased apparent strains within the complex. We propose that such highly strained regions are "hot spots" that can potentiate local tissue adaptation under physiological loading and adverse tissue adaptation under pathological loading conditions.