To study the clinical effects of soft occlusal splint and hard occlusal splint on the treatment of sleep bruxism or clenching.

58 patients with sleep bruxism or clenching were randomly treated with splints, 28 of them were treated with hard occlusal splint while the other 30 patients were treated with soft splints. All participants were asked to wear the splints during night and totally more than 8 h every day. Clinical effects such as muscle aches, bruxism or clenching habit and whether there are changes compared with before wearing were checked at 1, 2, 3, 6 months after treatment. The effective rates were compared by chi-square with SPSS 17.0.

The effective rates of soft and hard splint were 93.33% and 82.14% after 6 months' treatment, and there was no significant difference (P < 0.05).

Both hard occlusal splint and soft occlusal splint have good effects, and soft splint is more acceptable because it is easy to make and comfortable to be worn.