The polymerization even under wetting environment and under oxygen existing does not inhibit, is superior in arm edge blockade Characteristic, offer of the hardenability constituent for dentistry whose in addition grant of flexibility and control of removal Characteristic are possible. (A) the polymerizability monomer, and, (B) the organicity amine polymerization initiator is contained, being the constituent for dentistry, when aforementioned (A) in the component, (A) the weight section of the component) [as a,] the total of the component as 100 weight sections it contains the long-chain polymerizability monomer which has the structure above the numbers of chain long 17 atoms, or and/or (C) contains the soft resin material in the aforementioned constituent, and (A) the component as 100 weight sections designating when (A designates at the same time (A) the component and (B) designating (A), (B) and (C) the weight section of the componentWhen each one (a) and (b), (c) with doing, the 70 (a) the 99.99 and the 0.01 (b) the 30 and the 1 [a] /5+ (c) /1, the 0 [a] the 95 and the 0 (the hardenability constituent for dentistry which is c) 250.湿潤環境下、酸素存在下でも重合が阻害されず、辺縁封鎖性に優れ、また柔軟性の付与や除去性の制御が可能な歯科用硬化性組成物の提供。(A)重合性単量体、および、(B)有機アミン系重合開始剤を含有する、歯科用組成物であって、前記(A)成分中に、(A’)鎖長17原子数以上の構造を持つ長鎖重合性単量体を含有するか、および/または前記組成物中に(C)軟質樹脂材を含有し、そして(A)成分を100重量部としたときの(A’)成分の重量部を[a’]とし、且つ(A)成分と(B)成分の合計を100重量部としたときの(A)、(B)、(C)成分の重量部をそれぞれ(a)、(b)、(c)としたとき、70≦(a)≦99.99、0.01≦(b)≦30、1≦[a’]/5+(c)/1、0≦[a’]≦95、0≦(c)≦250である歯科用硬化性組成物。
