Penelitian dilakukan untuk mengetahui pengaruh perendaman dalam larutan kayu manis terhadap kekerasan mikro email gigi manusia dengan menggunakan Shimadzu Micro Hardness Tester HMV-2. Delapan spesimen gigi premolar atas manusia dibagi menjadi kelompok perendaman larutan 4% dan 12,5%, selama 60 menit, 120 menit, dan 180 menit. Pengukuran kekerasan menggunakan indenter Knoop, sebelum dan setelah perlakuan. Data dianalisis dengan Repeated ANOVA dan Independent T-Test. Perendaman dalam larutan 4% selama 60 menit dan 120 menit menurunkan kekerasan. Sebaliknya, perendaman selama 180 menit meningkatkan kekerasan. Perendaman dalam larutan 12,5% hingga180 menit menurunkan kekerasan. Perendaman gigi dalam larutan kayu manis dapat menyebabkan perubahan kekerasan.

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This research was conducted to understand the effect of immersion of the human tooth enamel in cinnamon extract solution to the enamel microhardness using Shimadzu Micro Hardness Tester HMV-2. Eight specimens of maxillary premolar soaked in 4% and 12,5% solution for 60 minutes, 120 minutes, and 180 minutes. Hardness measurements using Knoop indenter performed before and after treatment. Data were analyzed by Repeated ANOVA and Independent T-Test. Immersion in 4% solution for 60 minutes and 120 minutes reduce microhardness. Soaking for 180 minutes will increase microhardness. Soaking in 12,5% solution for 180 minutes reduce microhardness. Enamel immersion may change microhardness.