Abstract
Effect of orthodontic bracket bonding-debonding on fracture toughness of human dental enamel was investigated by using nano-indentation test. For this purpose, some ceramic brackets were bonded by a dental adhesive on the buccal surface of sound human teeth enamel. All clinical requirements were considered for bracket bonding and sample preparation. After debonding of the brackets, the teeth were sectioned transverse to their longitudinal axes and from the middle of the bracket region to prepare the samples required for nano-indentation tests. The nanoindentation test was performed on both the enamel under bracket and the intact enamel. The values of fracture toughness of dental enamel in both regions were calculated from the analysis of nano-scale holes observed after the nano-indentation tests. A comparison between the results obtained from the two regions indicated that bracket bonding-debonding significantly decreased the fracture toughness of human dental enamel.
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Ayatollahi, M.R., Karimzadeh, A. Nano-Indentation Measurement of Fracture Toughness of Dental Enamel. Int J Fract 183, 113–118 (2013). https://doi.org/10.1007/s10704-013-9864-x
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DOI: https://doi.org/10.1007/s10704-013-9864-x