S-Space College of Dentistry/School of Dentistry (치과대학/치의학대학원) Dept. of Dentistry (치의학과) Journal Papers (저널논문_치의학과)
점도, 시편형태 그리고 접착의 유무가 광중합 복합레진의 선형중합수축의 측정에 미치는 영향
THE EFFECT OF VISCOSITY, SPECIMEN GEOMETRY AND ADHESION ON THE LINEAR POLYMERIZATION SHRINKAGE MEASUREMENT OF LIGHT CURED COMPOSITES
- 이인복; 손호현; 권혁춘; 엄정문; 조병훈
- Issue Date
- 대한치과보존학회지 28 : 457 466, 2003.
- Anisotropy; Polymerization shrinkage; Bonded disc method; Flow; C-factor; Light cured composites
- The aim of study was to investigate the effect of flow, specimen geometry and adhesion on the measurement of linear polymerization shrinkage of light cured composite resins using linear shrinkage measuring device. Four commercially available composites - an anterior posterior hybrid composite Z100, a posterior packable composite P60 and two flowable composites, Filtek flow and Tetric flow-were studied. The linear polymerization shrinkage of composites was determined using 'bonded disc method' and 'non-bond-ed' free shrinkage method at varying C-factor in the range of 1∼8 by changing specimen geometry. These measured linear shrinkage values were compared with free volumetric shrinkage values. The viscosity and flow of composites were determined and compared by measuring the dropping speed of metal rod under constant load. In non-bonded method, the linear shrinkage approximated one third of true volumetric shrink-age by isotropic contraction. However, in bonded disc method, as the bonded surface increased the linear shrinkage increased up to volumetric shrinkage value by anisotropic contraction. The linear shrinkage value increased with increasing C-factor and approximated true volumetric shrinkage and reached plateau at about C-factor 5∼6. The more flow the composite was, reduced linear shrinkage was measured by compensation radial flow.