Gorseta Kristina, Glavina Domagoj, Skrinjaric Tomislav, Czarnecka Beata, Nicholson John W
Department of Paediatric and Preventive Dentistry, School of Dental Medicine, University of ZagrebCroatia.
Department of Biomaterials and Experimental Dentistry, University of Medical SciencesPoznańPoland.
Acta Biomater Odontol Scand. 2016 Mar 29;2(1):55-59. doi: 10.3109/23337931.2016.1160784. eCollection 2016 Dec.
This study determined the influence of coating with either petroleum jelly or light-cured varnish and storage medium on the flexural strength of glass-ionomer cements (GIC). The flexural strength of two glass-ionomer cements (Fuji Equia Fil and Ketac Molar Aplicap) was measured. Specimens (2 × 2 × 25 mm) were prepared in three groups: uncoated, coated with petroleum jelly, or coated with light-cured varnish (EquiaCoat) cured for 20 s using a cure lamp (Bluephase G2, Ivoclar Vivadent, Schaan, Liechtenstein). Specimens were stored for 1 week at 37 °C in water, artificial saliva or 20 mmol dm lactic acid, then flexural strength was determined in 3-pont bend. Data were analyzed by ANOVA and Tukey HSD test ( < 0.05). In addition, the mold was filled with water and the temperature change caused by the cure lamp was measured with a thermocouple. For both materials, storage in water gave the lowest flexural strength. It was slightly higher in either saliva or lactic acid, and was improved by coating in petroleum jelly. Specimens coated with light-cured varnish, that also involved heating with a cure lamp, gave the highest flexural strength. The heating effect of the lamp was demonstrated by the temperature rise in the water in the mold after light exposure from 21.9 (± 1.0) °C to 26.8 (± 1.0) °C. hence, sealing of GIC from aqueous media improves flexural strength. The cure lamp emitted heat, which may enhance the flexural strength of specimens coated with light-cured varnish.
本研究确定了涂覆凡士林或光固化清漆以及储存介质对玻璃离子水门汀（GIC）弯曲强度的影响。测量了两种玻璃离子水门汀（Fuji Equia Fil和Ketac Molar Aplicap）的弯曲强度。制备了三组尺寸为2×2×25mm的试样：未涂覆组、涂覆凡士林组或涂覆光固化清漆（EquiaCoat）组，后者使用固化灯（Bluephase G2，义获嘉伟瓦登特公司，列支敦士登公国沙恩）固化20秒。试样在37℃下于水、人工唾液或20mmol/dm乳酸中储存1周，然后通过三点弯曲测定弯曲强度。数据采用方差分析和Tukey HSD检验进行分析（P<0.05）。此外，向模具中注水，并用热电偶测量固化灯引起的温度变化。对于两种材料，在水中储存时弯曲强度最低。在唾液或乳酸中储存时弯曲强度略高，涂覆凡士林可提高弯曲强度。涂覆光固化清漆的试样（这也涉及用固化灯加热）弯曲强度最高。光照后模具中水的温度从21.9（±1.0）℃升高到26.8（±1.0）℃，证明了灯的加热效果。因此，将GIC与水性介质密封可提高弯曲强度。固化灯发出热量，这可能会提高涂覆光固化清漆试样的弯曲强度。
