Effects of prepolymerized particle size and polymerization kinetics on volumetric shrinkage of dental modeling resins.
Dental modeling resins have been developed for use in areas where highly precise resin structures are needed. The manufacturers claim that these polymethyl methacrylate/methyl methacrylate (PMMA/MMA) resins show little or no shrinkage after polymerization. This study examined the polymerization shrinkage of five dental modeling resins as well as one temporary PMMA/MMA resin (control). The morphology and the particle size of the prepolymerized PMMA powders were investigated by scanning electron microscopy and laser diffraction particle size analysis, respectively. Linear polymerization shrinkage strains of the resins were monitored for 20 minutes using a custom-made linometer, and the final values (at 20 minutes) were converted into volumetric shrinkages. The final volumetric shrinkage values for the modeling resins were statistically similar (P > 0.05) or significantly larger (P < 0.05) than that of the control resin and were related to the polymerization kinetics (P < 0.05) rather than the PMMA bead size (P = 0.335). Therefore, the optimal control of the polymerization kinetics seems to be more important for producing high-precision resin structures rather than the use of dental modeling resins.
Department of Dental Biomaterials, School of Dentistry, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea ; Department of Medical & Biological Engineering, Graduate School, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea.
Tae-Yub
0000-0002-9998-3099
TY
Kwon
Department of Medical & Biological Engineering, Graduate School, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea.
Jung-Yun
JY
Ha
Department of Medical & Biological Engineering, Graduate School, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea.
Ju-Na
JN
Chun
Korea Textile Development Institute, 1083 Jungri-dong, Seo-gu, Daegu 703-712, Republic of Korea.
Jun Sik
JS
Son
Department of Dental Biomaterials, School of Dentistry, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea ; Department of Medical & Biological Engineering, Graduate School, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu 700-412, Republic of Korea.
Kyo-Han
KH
Kim
D000180:Acrylic Resins / Q000737:chemistry*; D004548:Elasticity; D006801:Humans; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D003765:Models, Dental; D058105:Polymerization; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D013499:Surface Properties
D000180:Acrylic Resins; D019904:Polymethyl Methacrylate