The scores of visual analogue scale ( VAS ) and present pain intensity ( PPI ) after treatment were all improved significantly as compared with those before treatment in the @ groups ( all P < @ ) , and the result in the @ min group was superior to the other @ groups ( VAS : @ + / -@ vs @ + / -@ , @ + / -@ , @ + / -@ ; PPI : @ + / -@ vs @ + / -@ , @ + / -@ , @ + / -@ , all P < @ ) .