Sublingual group had significantly more cervical dilatation and shorter operative time than oral group ( 7.3 + / - 1.5 vs. 5.9 + / - 1.4 mm , p < 0.001 and 5.2 + / - 3.3 vs. 7.3 + / - 4.6 min , p = 0.02 , respectively ) .