We reviewed the literature from 1985 to 1996 concerning the preliminary treatment of disc dislocation with reduction (DDWR) by means of occlusal splints, pinpointing two main methods. The conflicting results of many papers induced us to make a literature meta-analysis of those articles with the necessary requirements in order to verify the effectiveness of the two therapeutic means more frequently used in DDWR; the repositioning splint and the bite plane. A statistical comparison between the two kinds of treatment has demonstrated that the repositioning splint is more effective both in the resolution of the articular click and of the pain at a level of P < or = 0.00001, which is noteworthy and highly significant.