Synthesis, characterization, and evaluation of star-shaped poly(acrylic acid)s as well as nanoparticles constructed glass-ionomer cements for improved dental restoratives
Abstract
Glass-ionomer cement (GIC) is a promising dental restorative material with numerous advantages. However, its inferior mechanical performances have limited its application to low-stress bearing sites. In this dissertation, we successfully improved the mechanical performance and wear resistance of glass-ionomer cement using two strategies: (1) modification on polymer matrix by using star-shaped poly(acrylic acid)s; and (2) modification of glass filler by using surface modified OX50 (SiO2) nanoparticles. Star-shaped poly(acrylic acid)s were synthesized using atom transfer radical polymerization (ATRP) reaction and then formulated into glass-ionomer cement. The resultant GIC showed significantly better mechanical performances and wear resistance than commercial GICs. It also exhibited significantly better biocompatibility. The fluoride release was maintained in the cements of star-shaped polymers, while the curing shrinkage was limited to a low level. Surface modification of OX50 nanoparticles was performed via surface-initiated ATRP reaction. OX50 surfaced modified with poly(acrylic acid) significantly improved the mixing property. Although little improvement in mechanical strength was found; a significant improvement in attritional wear resistance was observed for all the cements containing surface modified nanoparticles. In general, both strategies have proved effective to improve the mechanical performances and wear resistance of GIC.
Degree
Ph.D.
Advisors
Schmidt, Purdue University.
Subject Area
Biomedical engineering
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