Tujuan: Penelitian ini bertujuan untuk mengetahui perbedaan nilai kekerasan resin komposit microhybrid G-aenial Posterior™ setelah perendaman dalam saliva buatan dengan pH 4,5; 5,5; dan 7 selama 1 hari dan 7 hari.Metode Penelitian: Dalam penelitian ini digunakan 36 spesimen resin komposit microhybrid G-aenial Posterior™ berbentuk silinder dengan ukuran diameter 6 mm dan tebal 2 mm. Selembar mylar strip diletakkan diatas permukaan resin komposit sebelum dilakukan proses curing. Polimerisasi dilakukan menggunakan Light Curing Unit (LED DBA iLed) selama 10 detik dengan irradiansi 1200 mW/cm2. Setelah polimerisasi, spesimen direndam dalam akuades pada suhu 37oC selama 24 jam. Spesimen dibagi menjadi enam kelompok (n = 6) yaitu; perendaman pada saliva buatan pH 4,5 selama 1 hari, saliva buatan pH 5,5 selama 1 hari, saliva buatan pH 7 selama 1 hari, saliva buatan pH 4,5 selama 7 hari, saliva buatan pH 5,5 selama 7 hari, dan saliva buatan pH 7 selama 7 hari. Spesimen diuji menggunakan HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Jepang) dengan beban 50 gram selama 15 detik untuk mendapatkan nilai kekerasan. Data dianalisis dengan uji statistik One-Way ANOVA dan Post-Hoc Bonferroni. Hasil Penelitian: Hasil uji statistik menunjukkan penurunan bermakna nilai kekerasan material G-aenial PosteriorTM setelah dilakukan perendaman selama 1 dan 7 hari dalam saliva buatan dengan pH 4,5; 5,5; dan 7. Nilai kekerasan tertinggi terlihat pada resin komposit microhybrid G-aenial Posterior™ setelah perendaman 1 hari pada pH saliva buatan pH 7 yaitu sebesar 19,14 ± 0,61 VHN. Sedangkan nilai kekerasan terendah terlihat pada resin komposit microhybrid G-aenial Posterior™ setelah perendaman 7 hari pada pH saliva buatan pH 4,5 yaitu sebesar 14,37 ± 0,31 VHN. Kesimpulan: Disimpulkan bahwa dengan pertambahan waktu perendaman, dan penurunan pH saliva buatan didapatkan nilai kekerasan yang menurun pada resin komposit microhybrid G-aenial PosteriorTM.

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Objective: The aim of this study was to determine the difference of Microhybrid G-Aenial Posterior™ Composite Resin hardness value after immersion in artificial saliva with pH 4.5; 5.5; and 7 for 1 day and 7 days. Method: 36 specimens of Microhybrid G-Aenial Posterior™ Composite Resin were used in this study. All materials were prepared into disk-shaped specimens of 6 mm in diameter and 2 mm in thickness. A piece of mylar strip was placed on the top of the specimens just before the polymerization. Polymerization was done using LED curing unit (LED DBA iLed) in 10 seconds with irradiance 1200 mW/cm2. After polymerization, specimens were immersed in 37C aquadest solution for 24 hours. Specimens were divided into six groups (n=6) immersed with artificial saliva pH 4,5 in a day; pH 5,5 in a day; pH 7 in a day; pH 4,5 in 7 days; pH 5,5 in 7 days; and pH 7 in 7 days. Specimens were tested with HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Japan) with 50 gram indentation in 15 seconds. Data were analyzed using One-Way ANOVA and Post-Hoc Bonferroni to assess the significant differences among groups. Result: The result showed hardness significant decreased of G-aenial PosteriorTM after were immersed in 1 and 7 days in 4,5; 5,5; dan 7 pH of artificial saliva. The highest and lowest hardness value seen in microhybrid G-aenial Posterior™ composite resin after were immersed in one day with pH 7 of artificial saliva (19,14 ± 0,61 VHN) and 7 days with pH 4,5 (14,37 ± 0,31 VHN) respectively. Conclusion: It was concluded that the increased immersion time and the decrease in the pH value of the artificial saliva decreased the hardness value of the G-aenial PosteriorTM microhybrid composite resin.