<![CDATA[Periodontitis is a condition that affects the supporting structure of the teeth and causes tooth loss. Indonesia has a variety of medicinal plants, one of which is ant's nest (Myrmecodia tuberosa jack) which contains various secondary metabolites. To determine the antibacterial activity of Kalimantan anthill extract (Myrmecodia tuberosa jack) in inhibiting the growth of Treponema denticola bacteria. This research is a pure experimental research (true experimental) with post test only control group design. Ant-nest extract (Myrmecodia tuberosa jack) was made by maceration method using 96% ethanol and then serial dilution. The results showed antibacterial activity at concentrations of 80 mg/mL and 40 mg/mL which means it has bacteriostatic properties with a p value = 0.003 which means there is a very significant difference in each concentration of anthill extract and the results of the Minimum Bactericidal Concentration (MBC) did not show any killing power against Treponema denticola bacteria. Ant-nest extract (Myrmecodia tuberosa jack) has the ability to inhibit the growth of Treponema denticola bacteria and there are very significant differences in each concentration of ant nest extract (Myrmecodia tuberosa jack) against Treponema denticola bacteria. Keywords: Ethanol extract, Myrmecodia tuberosa jack, Chronic periodontitis, Treponema denticola Abstrak Periodontitis adalah kondisi yang mempengaruhi struktur penyangga gigi dan menyebabkan gigi goyah bahkan tanggal. Indonesia memiliki beragam tanaman obat, salah satunya sarang semut (Myrmecodia tuberosa jack) yang mengandung berbagai metabolit sekunder. Mengetahui aktivitas antibakteri ekstrak sarang semut Kalimantan (Myrmecodia tuberosa jack) dalam menghambat pertumbuhan bakteri Treponema denticola. Penelitian ini merupakan penelitian eksperimental murni (true experimental) dengan post test only control group design. Ekstrak sarang semut (Myrmecodia tuberosa jack) dibuat dengan metode maserasi menggunakan etanol 96% lalu dilakukan serial dilusi. Hasil penelitian menunjukan adanya aktivitas antibakteri pada konsentrasi 80 mg/mL dan 40 mg/mL yang berarti memiliki sifat bakteriostatik dengan nilai p= 0,003 yang berarti terdapat perbedaan sangat signifikan pada setiap konsentrasi ekstrak sarang semut dan hasil Konsentrasi Bunuh Minimum (KBM) tidak menunjukan adanya daya bunuh terhadap bakteri Treponema denticola. Ekstrak sarang semut (Myrmecodia tuberosa jack) memiliki kemampuan untuk menghambat pertumbuhan bakteri Treponema denticola dan terdapat perbedaan yang sangat bermakna pada tiap konsentrasi ekstrak sarang semut (Myrmecodia tuberosa jack) terhadap bakteri Treponema denticola. Kata Kunci: Ekstrak Etanol, Treponema denticola, Myrmecodia tuberosa jack, Periodontitis kronis]]>
