2Veerkamp SJ,Gruythuysen RJ,Hoogstraten J,et al.Dental treatment of fearful children using nitrous oxide.Part4:Anxiety after two years ASDC.J Dent Child,1993,60:372.
2Klorman R, Michael R, Hilpert PL, et al .A further assessment of predictors of the child behavior in dental treatment [J]. J Dent Res ,1979,58:2238.
3Hoist A, Hallonsten AL, Schroder U, et al . Prediction of behavior management problems in 3 year old Children[J]. Stand J Dent Res ,1993,01(2):110-112.
4Veerkamp SJ, Gruythuysen RJ M and Hoogstraten J, et al . Dental treatment of fearful children using nitrous oxide. Part 4:Anxiety after two years ASDC[J]. J Dent Child , 1993, 60:372.