<![CDATA[Abstract: Denture stomatitis is caused by food debris sticking to the surface of the denture plate becoming a habitat for the growth of Staphylococcus aureus bacteria. The increase in the number of Staphylococcus aureus in the oral cavity can be overcome by maintaining the cleanliness of the denture plate. Denture cleaning can use natural materials such as sea urchin extract which is known of its antibacterial potential due to its active compounds such as flavonoids, saponins, steroids, alkaloids, phenols, and tannins. This study aimed to test the inhibition of Diadema setosum sea urchin extract against the growth of Staphylococcus aureus bacteria on artificial tooth plates. This was a laboratory experimental study with a post-test control group design using the disc diffusion method. Samples were divided into six groups: sea urchin Diadema setosum extract 10%, 30%, 50%, and 70%, positive control (manufactured denture cleaner), and negative control (distilled water). The test was conducted at the Microbiology Laboratory of Pharmacy FMIPA Sam Ratulangi University. The results showed that Diadema setosum sea urchin extract was able to inhibit the growth of Staphylococcus aureus bacteria at all test concentrations, with the largest inhibition zone found at 70% concentration (medium category). In conclusion, Diadema setosum sea urchin extract can inhibit the growth of Staphylococcus aureus bacteria on denture plates Keywords: Diadema setosum; sea urchin; Staphylococcus aureus Abstrak: Denture stomatitis disebabkan oleh sisa makanan menempel pada permukaan plat gigi tiruan dan menjadi habitat untuk berkembang biaknya bakteri Staphylococcus aureus. Peningkatan jumlah Staphylococcus aureus dalam rongga mulut dapat diatasi dengan menjaga kebersihan plat gigi tiruan. Pembersih gigi tiruan dapat menggunakan bahan dari alam seperti ekstrak landak laut Diadema setosum yang memiliki potensi antibakteri karena kandungan senyawa aktif seperti flavonoid, saponin, steroid, alkaloid, fenol, dan tanin. Penelitian ini bertujuan untuk menguji daya hambat ekstrak landak laut Diadema setosum terhadap pertumbuhan bakteri Staphylococcus aureus pada plat gigi tiruan. Penelitian dilakukan secara eksperimental laboratorium dengan post-test control group design menggunakan metode difusi cakram. Sampel dibagi menjadi enam kelompok: ekstrak landak laut Diadema setosum 10%, 30%, 50%, dan 70%, kontrol positif (pembersih gigi tiruan pabrikan), serta kontrol negatif (akuades). Pengujian dilakukan di Laboratorium Mikrobiologi Farmasi FMIPA Universitas Sam Ratulangi. Hasil penelitian menunjukkan bahwa ekstrak landak laut Diadema setosum mampu menghambat pertumbuhan bakteri Staphylococcus aureus pada seluruh konsentrasi uji, dengan zona hambat terbesar ditemukan pada konsentrasi 70% (kategori sedang). Simpulan penelitian ini ialah ekstrak landak laut Diadema setosum mempunyai daya hambat terhadap pertumbuhan bakteri Staphylococcus aureus pada plat gigi tiruan. Kata kunci: landak laut; Diadema setosum; Staphylococcus aureus]]>
