Reduction in Parafunctional Activity: A Potential Mechanism for The Effectiveness of Splint Therapy.
Glaros AG, Owais Z, Lausten L. J Oral Rehabil. 2007;34:97-104.
Interocclusal splints may be an effective modality in the management of temporomandibular disorders (TMD), but there is little evidence regarding the mechanism by which splints work. This study tested the hypothesis that pain reduction produced by splints is associated with reduction in parafunctional activity. In a two-group, single-blinded randomized clinical trial, patients diagnosed with myofascial pain received full coverage hard maxillary stabilization splints. Patients were instructed to maintain or avoid contact with the splint for the 6 weeks of active treatment. Patients who decreased the intensity of tooth contact were expected to show the greatest alleviation of pain, and those who maintained or increased contact were expected to report lesser reductions in pain. Experience-sampling methodology was used to collect data on pain and parafunctional behaviours at pre-treatment and during the final week of treatment. Patients were reminded approximately every 2 h by pagers to maintain/avoid contact with the splint. The amount of change in intensity of tooth contact accounted for a significant proportion of the variance in pain change scores. Patients who reduced tooth contact intensity the most reported greater relief from pain. Splints may produce therapeutic effects by reducing parafunctional activities associated with TMD pain.
Splint therapy, also known as intraoral orthotic treatment, is the most common therapeutic approach used to treat patients with diagnosed temporomandibular disorders (TMD). In this age of minimally invasive dentistry, splints offer a conservative treatment for TMD. There is significant variety in the types and forms of splints being used, including hard and soft splints, as well as differences in the rationales for their use. In some patients, TMD symptoms can be treated with psychological or behavioral treatment approaches. The authors of this well-designed study evaluated the effect of parafunction on the effectiveness of stabilization splint therapy for patients with myalgia and/or arthralgia. Would a reduction in parafunctional activity with the use of a splint contribute to pain reduction for these patients? While typically clinical studies report restorative treatment techniques and periodontal treatment results, the efforts these researchers used to recruit patients who met their strict criteria were well-designed. Each patient evaluated was screened with muscle palpation and with panoramic radiographs. The patients selected received a maxillary flat-plane acrylic interocclusal splint and assigned to two groups, either an Avoid Contact or Maintain Contact group. After 6 weeks the patients were evaluated for changes in pain. An analysis of the data revealed the success of occlusal splints in the treatment of TMD pain and that intervening with patient behavior through targeted treatment of parafunctional activity improves the effectiveness of the splint treatment. The results of this study parallel Ficton’s systematic review of current evidence that the management of TMD-splint therapy works.1 When a patient presents with TMD symptoms, after a thorough examination to confirm the diagnosis, consider the use of splint therapy to alleviate the symptoms.
1. Ficton J. Current evidence providing clarity in management of temporomandibular disorders: summary of a systematic review of randomized clinical trials for intra-oral appliances and occlusal therapies. J Evidence Base Dent Pract. 2006;6:48-52.
|About the Author|
Howard E. Strassler, DMD