Abstract:
Flexural strength, flexural modulus, surface hardness, water sorption, water
solubility, level of residual monomer and biocompatibility are important properties of
self-cured orthodontic resins. The purpose of this study is to compare these properties
of a Thai self-cured orthodontic resin with the commercial product (Orthocryl®). The
tested specimens were classified into 4 groups according to their types and fabrication
techniques (Thai-mixing, Thai-infiltration, Orthocryl®-mixing, Orthocryl®-infiltration)
and were tested by the methods described by ISO 1567:1999 which is the international
standard for dental polymers. Flexural strength, flexural modulus, surface hardness,
water sorption, water solubility, residual monomer and biocompatibility of the resins
were determined. Kruskal-Wallis, Mann-Whitney and One-Sample T tests (P<.05)
were used to compare significant differences in the levels of these properties among
the four groups of self-cured orthodontic resins. According to ISO1567:1999, the
properties of the Thai resin were acceptable. The surface hardness of Orthocryl® was
significantly higher than that of the Thai resin. Water sorption and solubility of
Orthocryl® were significantly lower than those of the Thai resin. However, there were
no significant differences in flexural strength, flexural modulus and level of residual
monomer between Orthocryl® and the Thai resin . The specimens prepared by mixing
and infiltration technique showed no significant differences in levels of flexural
strength, flexural modulus, surface hardness, water sorption, water solubility and
residual monomer.
This study suggests that the Thai self-cured orthodontic resin is suitable as an
alternative orthodontic denture base. Also, this study will serve as a guidance for
further development of Thai self-cured orthodontic resin.