< Topic >The gypsum knife for dentistry skill manufacture to which the blade is difficult to break, vis-a-vis the gypsum efficiently can cut is offered.SolutionsCross section is shaved on the curved surface with the form of the knife as a middling.< Choice figure >Drawing 1【課題】刃が折れにくく、石膏に対し効率よく切削できる歯科技工用石膏ナイフを提供する。【解決手段】ナイフの形状を片刃にして断面形状を曲面に削る。【選択図】図1