title: Measurement of Poisson's ratio of dental composite restorative materials.
abstract: The aim of this study was to determine the Poisson ratio of resin-based dental composites using a static tensile test method. Materials used in this investigation were from the same manufacturer (3M ESPE) and included microfill (A110), minifill (Z100 and Filtek Z250), polyacid-modified (F2000), and flowable (Filtek Flowable [FF]) composites. The Poisson ratio of the materials were determined after 1 week conditioning in water at 37 degrees C. The tensile test was performed with using a uniaxial testing system at crosshead speed of 0.5 mm/min. Data was analysed using one-way ANOVA/post-hoc Scheffe's test and Pearson's correlation test at significance level of 0.05. Mean Poisson's ratio (n=8) ranged from 0.302 to 0.393. The Poisson ratio of FF was significantly higher than all other composites evaluated, and the Poisson ratio of A110 was higher than Z100, Z250 and F2000. The Poisson ratio is higher for materials with lower filler volume fraction.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074, Singapore. rsdcsm@nus.edu.sg
authors.forename: Sew Meng
authors.initials: SM
authors.lastname: Chung
authors.forename: Adrian U Jin
authors.initials: AU
authors.lastname: Yap
authors.forename: Wee Kiat
authors.initials: WK
authors.lastname: Koh
authors.forename: Kuo Tsing
authors.initials: KT
authors.lastname: Tsai
authors.forename: Chwee Teck
authors.initials: CT
authors.lastname: Lim
mesh_terms: D003764:Dental Materials; D003793:Dental Restoration, Permanent; D008422:Materials Testing; D016012:Poisson Distribution
chemical_list: D003764:Dental Materials