6Liddell A, Gosse V. Characteristics of early unpleasant dental experiences [J]. J Behav Ther Exp Psychiatry,1998,29(3):227-237.
7Locker D, Liddell A. Age of onset of dental anxiety [J]. J Dent Res,1999,78 (3):790-796.
8Cohen LA,Snyder TL,LaBelle A D.Correlates of denal anxiety in a university population[J].J Public Health Dent,1982,42 (3):228-235.Assoc,1988,116(6):641-647.
9Chapman H R.Kirby-Tumer N C[J].Br Dent J,1999,187(1):408-412.
