Instrumentasi saluran akar masih meninggalkan area tidak terpreparasi. Insrumen osilasi diklaim dapat membersihkan dinding saluran akar secara optimal.Tujuan: Membandingkan luas dinding sepertiga apeks saluran akar yang tidak terpreparasi antara instrumen osilasi Reciproc® dan WaveOne®.Metode: Tiga puluh dua saluran akar premolar mandibula diisi tinta cina kemudian dibagi menjadi dua kelompok berjumlah sama (n=16): Reciproc® dan WaveOne®. Luas dinding yang tertutup tinta cina dianalisis dengan Adobe Photoshop CS5.Hasil: Kelompok II mempreparasi lebih banyak dinding tetapi tidak berbeda bermakna dengan kelompok I (p=0,265).Kesimpulan: Reciproc® dan WaveOne® tetap meninggalkan area tidak terpreparasi di sepertiga apeks saluran akar.

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Thirty five percents area of root canal wall was left uninstrumented after instrumentation. Oscillation instrument was claimed able to clean whole area of root canal walls.Objective: to compare uninstrumented area of root canal at the apical third after instrumented by oscillation instrument.Methods: Thirty two human mandibular premolar root canals were dyed with china ink and were divided equally into Reciproc® and WaveOne® group. The area was analyzed using Adobe Photoshop CS5.Results: WaveOne® showed a better result than Reciproc®, but not statistically significant (p=0,265).Conclusion: The Reciproc® and WaveOne® showed no difference in cleaning the root canal.