PURPOSE: The metabolic processes that regulate bone healing and bone induction in tissue engineering models are not fully understood. Eddy current excitation is widely used in technical approaches and in the food industry. The aim of this study was to establish eddy current excitation for monitoring metabolic processes during heterotopic osteoinduction in vivo. METHODS: Hydroxyapatite scaffolds were implanted into the musculus latissimus dorsi of six rats. Bone morphogenetic protein 2 (BMP-2) was applied 1 and 2 weeks after implantation. Weekly eddy current excitation measurements were performed. Additionally, invasive pH measurements were obtained from the scaffolds using fiber optic detection devices. Correlations between the eddy current measurements and the metabolic values were calculated. RESULTS: The eddy current measurements and pH values decreased significantly in the first 2 weeks of the study, followed by a steady increase and stabilization at higher levels towards the end of the study. The measurement curves and statistical evaluations indicated a significant correlation between the resonance frequency values of the eddy current excitation measurements and the observed pH levels (p = 0.0041). CONCLUSIONS: This innovative technique was capable of noninvasively monitoring metabolic processes in living tissues according to pH values, showing a direct correlation between eddy current excitation and pH in an in vivo tissue engineering model.
PURPOSE: The metabolic processes that regulate bone healing and bone induction in tissue engineering models are not fully understood. Eddy current excitation is widely used in technical approaches and in the food industry. The aim of this study was to establish eddy current excitation for monitoring metabolic processes during heterotopic osteoinduction in vivo. METHODS:Hydroxyapatite scaffolds were implanted into the musculus latissimus dorsi of six rats. Bone morphogenetic protein 2 (BMP-2) was applied 1 and 2 weeks after implantation. Weekly eddy current excitation measurements were performed. Additionally, invasive pH measurements were obtained from the scaffolds using fiber optic detection devices. Correlations between the eddy current measurements and the metabolic values were calculated. RESULTS: The eddy current measurements and pH values decreased significantly in the first 2 weeks of the study, followed by a steady increase and stabilization at higher levels towards the end of the study. The measurement curves and statistical evaluations indicated a significant correlation between the resonance frequency values of the eddy current excitation measurements and the observed pH levels (p = 0.0041). CONCLUSIONS: This innovative technique was capable of noninvasively monitoring metabolic processes in living tissues according to pH values, showing a direct correlation between eddy current excitation and pH in an in vivo tissue engineering model.
Authors: Benedicta Elisabeth Beck-Broichsitter; David W Christofzik; Frank Daschner; Reinhard Knöchel; Ralf Smeets; Patrick Warnke; Jörg Wiltfang; Stephan T Becker Journal: Tissue Eng Part C Methods Date: 2012-05-04 Impact factor: 3.056
Authors: Hermann Seitz; Wolfgang Rieder; Stephan Irsen; Barbara Leukers; Carsten Tille Journal: J Biomed Mater Res B Appl Biomater Date: 2005-08 Impact factor: 3.368
Authors: S T Becker; H Bolte; K Schünemann; H Seitz; J J Bara; B E Beck-Broichsitter; P A J Russo; J Wiltfang; P H Warnke Journal: Int J Oral Maxillofac Surg Date: 2012-05-29 Impact factor: 2.789
Authors: Stephan T Becker; Hendrik Bolte; Oliver Krapf; Hermann Seitz; Timothy Douglas; Sureshan Sivananthan; Jörg Wiltfang; Eugene Sherry; Patrick H Warnke Journal: Oral Oncol Date: 2009-08-31 Impact factor: 5.337