Abstract
Bis-GMA, 2.2-bis[p(2-hydroxy-3-methacryloyloxypropokyl)phenyl]Propane, is an essential component as a multifunctional methacrylate prepolymer in the light-curable polymeric dental composite resins. Two hydroxyl groups of the Bis-GMA molecule are considered to induce water sorption of the photocured composite resin in a mouth, resulting in gradual long-term deterioration of aesthetics and mechanical properties of the composite resins. In this study, some additives such as light stabilizer and antioxidant were added to composite resins to promote durability and storage stability of the last product. First of all, color change increased as a light stabilizer. Tinuvin P, was added to the composed resins and color stability was improved as an antioxidant, Irganox 245, was added to ones. In addition, when Tinuvin P and Irganox 245 were added together to the composed resins. the color stability was enhanced and mechanical properties such as diametral tensile strength before and after acceleration tests were also not greatly decreased. Therefore, when 0.5 weight Percent of Tinuvin P and 0.1 weight percent of Irganox 245 were added together to dental composite resins. the durability and color stability were enhanced, and furthermore the storage stability was also improved for the composed resins.
2.2-Bis[P-(2-hydroxy-3-methacryloyloxypropoxyl)phenol]propane (Bis-GMA)는 광중합형 치과용 고분자 복합레진의 다관능성 유기물로 널리 사용되고 있다. Bis-GMA는 두 개의 히드록시기를 가지고 있어서 구강내에서 광중합되는 복합레진의 물흡수를 야기시켜 장기간 점진적으로 심미성이 감소하고 결국엔 복합레진의 기계적 특성까지 저하시키게 된다. 본 연구에서는 최종제품의 내구성과 저장안정성을 향상시키기 위하여 복합레진에 광안정제와 산화방지제를 첨가제로 사용하였다. 먼저 Tinuvin P의 광안정제를 첨가하면 색변화가 큰 것을 볼 수 있었으나 Irganox 245의 산화방지제를 첨가하였을 때 색안정성이 향상됨을 알 수 있었다. 또한 Tinuvin P와 Irganox 245가 동시에 첨가되었을 때 색안 정성이 향상되며 시료의 가속화 실험 전과 가속화 후 간접인장강도와 같은 기계적 성질도 크게 감소되지 않았다. 따라서 치과용 복합레진의 제조에 있어서 첨가제인 Tinuvin P와 Irganox 245가 각각 0.5% 및 0.1% 첨가되었을 때 내구성 및 색안정성이 향상되었으며 나아가 저장 안정성도 향상됨을 확인할 수 있었다.
