[Penelitian ini bertujuan untuk menganalisa pengaruh waktu penyinaran resin komposit nanofil menggunakan Light Curing Unit (LCU) LED protototipe terhadap temperatur atap pulpa gigi. Spesimen berupa 30 gigi premolar 1 rahang atas yang dibagi menjadi 3 kelompok dengan jumlah spesimen 10 untuk setiap kelompok. Gigi kemudian direstorasi resin komposit nanofil dan disinari menggunakan LCU LED prototipe selama 10 atau 20 detik dan komersial selama 20 detik. Pengukuran temperatur dilakukan sebelum dan setelah penyinaran resin komposit dan temperatur atap pulpa yang dihasilkan oleh LCU LED prototipe selama 10 atau 20 detik lebih rendah secara signifikan dari yang dihasilkan oleh LCU LED komersial., The aim of the present research was to analyze the effect of curing duration of nanofilled composite resin by the prototype curing light on pulp roof temperature. Thirty extracted human maxillary premolars were divided into 3 groups, 10 specimens for each group. Each teeth restored using nanofilled composite resin and were cured by the prototype LED curing light in 10 or 20 seconds or the commercially available in 20 seconds as a comparison. Pulp roof temperature was measured before and after the curing process. As a result, the temperature induced by the prototype curing light in both 10 or 20 seconds were significantly lower compared to the commercially available.]