Centric splints more effective than distraction splints in anterior disc displacement without reduction?

摘要

DESIGN: A single-blind randomised controlled trial was conducted in a university prosthodontics department in Germany. INTERVENTION: Only people who presented a clear-cut clinical diagnosis of anterior disc displacement without reduction (ADDWR) were included: limited mouth opening with deflection, and limited lateral movement of the incisors and/or pain had to be found. Additionally, patients had to present at least one antagonistic molar contact on each side. The clinical finding was verified by magnetic resonance images in open and closed mouth positions. After clinical examination and imaging, centric splints or distraction splints were randomly assigned. Patients were instructed to wear the splint 18 h each day. Directions as to the care of the splint were given. OUTCOME MEASURE: After 1, 3 and 6 months of therapy, patients provided their subjective evaluation by filling out a visual analogue scale form. Any change in their pain level or functional performance level was recorded. The outcome was evaluated using the Wilcoxon signed rank test for matched pairs. Success after 6 months was defined as improvement in active mouth opening of greater than 20% and pain reduction (on chewing) of at least 50%. Success was statistically verified using a logistic regression test. RESULTS: A total of 74 patients (65 females and nine males) fulfilled the inclusion criteria and agreed to participate. Thirty-eight patients received a centric splint and 36 a distraction splint. The improvements in mouth opening were significant in both groups. The improvements in pain on chewing, pain during other functions, pain at rest, functional limitation on chewing and other functions were also comparable in the two groups. The logistic regression test, however, suggested that patients using centric splints were treated more successfully than the others (odds ratio, 2.88; 95% confidence interval, 1.01-8.74). CONCLUSIONS: Centric splints seem to be more effective than distraction splints. Therefore, before the surgical treatment of ADDWR, centric splints should be used instead of distraction splints.