Year : 2008 | Volume
: 19 | Issue : 3 | Page : 196--203
Soft occlusal splint therapy in the management of myofascial pain dysfunction syndrome: A follow-up study
Venkatesh Naikmasur, Puneet Bhargava, Kruthika Guttal, Krishna Burde
Department of Oral Medicine and Radiology, SDM College of Dental Sciences, Sattur, Dharwad - 580 009, Karnataka, India
Department of Oral Medicine and Radiology, SDM College of Dental Sciences, Sattur, Dharwad - 580 009, Karnataka
Background and Objectives: Myofascial Pain Dysfunction Syndrome (MPDS) has been recognized as the most common, nontooth-related chronic orofacial pain condition that confronts dentists. A variety of therapies has been described in literature for its management. The present study is a prospective study carried out to evaluate the efficacy of occlusal splint therapy and compare it with pharmacotherapy (using analgesics and muscle relaxants) in the management of Myofascial Pain Dysfunction Syndrome.
Materials and Methods: Forty patients in the age range of 17-55 years were included in the study and randomly assigned to one of two equally sized groups, A and B. Group A patients received a combination of muscle relaxants and analgesics while Group B patients received soft occlusal splint therapy. All the patients were evaluated for GPI, VAS, maximum comfortable mouth opening, TMJ clicking and tenderness during rest and movement as well as for the number of tender muscles at the time of diagnosis, after the 1 st week of initiation of therapy and every month for three months of follow-up.
Results: There was a progressive decrease in GPI scores, number of tender muscles, TMJ clicking and tenderness with various jaw movements and significant improvement in mouth opening in patients on occlusal splint therapy during the follow-up period as compared to the pharmacotherapy group.
Conclusion: Occlusal splint therapy has better long-term results in reducing the symptoms of MPDS. It has better patient compliance, fewer side effects, and is more cost-effective than pharmacotherapy; hence, it can be chosen for the treatment of patients with MPDS.
|How to cite this article:|
Naikmasur V, Bhargava P, Guttal K, Burde K. Soft occlusal splint therapy in the management of myofascial pain dysfunction syndrome: A follow-up study.Indian J Dent Res 2008;19:196-203
|How to cite this URL:|
Naikmasur V, Bhargava P, Guttal K, Burde K. Soft occlusal splint therapy in the management of myofascial pain dysfunction syndrome: A follow-up study. Indian J Dent Res [serial online] 2008 [cited 2021 Oct 19 ];19:196-203
Available from: https://www.ijdr.in/text.asp?2008/19/3/196/42950
The temporomandibular joint (TMJ) forms one of the most fascinating and complex synovial systems in the body. Movements of the TMJ are regulated by an intricate neurological controlling mechanism, which is essential for the system to function normally and efficiently.  Lack of such harmony may cause disruptive muscle behavior or structural damage to any of the components.
In 1934, Costen first described a syndrome that included facial and head pain and temporomandibular joint dysfunction, which was known as temporomandibular joint pain dysfunction syndrome (TMJPDS). Over the years, several diagnostic terms have been suggested by various authors for musculoskeletal disorders of the temporomandibular region, reflecting the different theories of etiology probably responsible for the various signs and symptoms presenting in the patients. The term, "Myofascial Pain Dysfunction Syndrome" was initially coined by Laskin in 1969.  Even though the condition is common, it is not well understood by most dental practitioners. The reason is probably related to the diversity of views expressed and a difficulty in comprehending its natural history and symptomatology.
Consequently, many different therapies-some conservative and reversible, others irreversible, including surgery and repositioning of the mandible, have been advocated for patients with TMJ dysfunction. Due to the difficulty in determining the etiology and the possibility that the symptoms are secondary to some other disorders of TMJ or muscles of mastication, initial treatment given should be reversible. 
Occlusal splint therapy is chosen for the treatment of dysfunctions in the orofacial region for several reasons. It is relatively simple, reversible, noninvasive and costs less than other treatments. Soft splints have been advocated for patients with TMD. They can be made for maxillary arches and are easily constructed and often inserted immediately at the initial examination. A high degree of patient acceptance has been reported with soft splints. The soft, resilient material may help in distributing the heavy load that occurs during parafunctional activity. 
A wide variety of drug classes have been described for chronic orofacial pain, ranging from short-term treatment with Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) and muscle relaxants for pain of muscular origin to long-term administration of antidepressants for less well-characterized pain.
In this context, this study was carried out to evaluate the efficacy of conventional soft occlusal splint therapy in comparison to pharmacotherapy with a combination of analgesics and muscle relaxants in the management of Myofascial pain dysfunction syndrome.
Materials and Methods
This prospective study was conducted in the Department of Oral Medicine and Radiology in the SDM College of Dental Sciences, Dharwad. Subjects were selected from a consecutive series of Myofascial pain dysfunction syndrome patients from the Department of Oral medicine over a period of November 2004 to March 2006.
Adult patients suffering from chronic Myofascial pain for a minimum duration of three months and willing to participate in the study.
The diagnosis of Myofascial Pain Dysfunction Syndrome in these patients was based on the clinical features outlined by Eversole and Machado.  These include i) tender muscles of mastication, often accompanied by neck and strap muscles tenderness, ii) Restricted or deviated mandibular movement caused by muscular restriction, iii) No clinical or radiographic evidence of internal derangement.
The more recent RDC-TMD criteria were not incorporated in the study as they have not been validated in the Indian population.
Patients with the following conditions were excluded from the study: occlusal disharmony, those undergoing orthodontic treatment and/or occlusal corrections, any form of arthritis affecting the TMJ and patients undergoing treatment from a psychiatrist for psychological disorders associated with pain in the TMJ region.
The experimental protocol for this study underwent review and approval by the Ethical Committee of the institution. The disease process and treatment procedures were fully explained to each patient and consent was obtained before the commencement of the study.
A detailed history was recorded for each patient at the time of diagnosis regarding onset, duration and progress of symptoms. Pain characteristics like type, nature and severity were noted. Pain response to jaw activities such as mastication, phonation, and deglutition were also recorded. The impact of pain on the global functional ability related to jaw use was assessed using a six-point Global Pain Impact scale (GPI).  Intensity rates of pain were recorded on a Visual Analog Scale, 100 mm-long continuum (VAS).  The extremes were labeled as no pain and worst possible pain.
After taking history, maximum comfortable mouth opening of all patients was recorded. Temporomandibular joint examination included assessment of clicking, tenderness at rest and during various jaw movements (opening, closing, right and left lateral, protrusion and retrusion) and deviation during opening and closing movements. Both study and control groups were matched for mouth opening and TMJ clicking [Table 1] and [Table 2]. Tenderness of the muscles of mastication and the neck muscles was assessed by means of digital palpation, resistance testing and functional manipulation of the muscles.  The tenderness in the muscle was recorded as being present or absent. Extraoral masticatory muscles such as the temporalis and masseter, were palpated with a digital pressure of 2 lb/in 2 . The medial and lateral pterygoids were evaluated by functional manipulation. 
Forty patients diagnosed with Myofascial Pain Dysfunction Syndrome were selected for the study and randomly assigned to two equally sized groups, A and B consisting of 20 patients each. The mean ages of the patients were 35.85 and 25.85 years in Groups A (pharmacotherapy group) and B (Occlusal splint therapy group), respectively. Group A was comprised of 40% males and 60% females, whereas Group B was comprised of 30% males and 70% females.
Group A (the positive control group) received an orally administered combination of muscle relaxants and analgesics comprising of Ibuprofen 400 mg, Paracetamol 325 mg, and Chlorzoxazone 250 mg in two doses daily for a period ranging from 5-7 days initially. If the patients reported with recurrence of pain during their post treatment follow-up, they were advised to repeat the same treatment regimen.
Group B was treated with Occlusal splint therapy for a period of three months. Patients were instructed to wear the splint at night to take care of parafunctional habits if any. In both the groups, subjective and objective assessments were evaluated at the time of diagnosis, after the first week of initiation of therapy and every month for three months of follow-up. The author himself performed the follow-up examination without any blinding.
Fabrication and adjustment of the occlusal splint
An alginate impression of the maxillary and mandibular arches was made. A soft occlusal splint was fabricated from a 3 mm-thick, soft polyvinyl sheet [Figure 1]. The sheet was adapted to a maxillary cast. The fabrication was done in a vacuum former, pressure moulding device [Figure 2] (BIOSTARŪ SCHEU-DENTAL GmbH, Iserlohn, Germany) with a thermally controlled, infrared heater. This machine accomplished vacuum suctioning of the warmed sheet of thick, resilient mouthguard material (BIOPLASTŪ SCHEU-DENTAL GmbH, Iserlohn, Germany) over the maxillary cast [Figure 3]. When the sheet had properly adapted to the cast in the vacuum former, it was taken out. The splint was then separated from the cast with a laboratory knife/scissors, the edges were smoothed and the palatal area removed. The splint was then disinfected with 2% gluteraldehyde and placed in the patient's mouth to check for retention. Chair side occlusal adjustment was made by evenly warming the occlusal surface of the splint with an alcohol torch before insertion into the patient's mouth. A functional imprint was developed in centric using bilateral, centric relation manipulation such that it had evenly distributed bilateral, posterior contact with little or no contact with the anterior teeth when in centric occlusion. Anterior guidance provided posterior separation in excursive movement. A carbide bur was used to remove the excess material from the imprint to develop the desired occlusal pattern. The soft splint was then polished with pumice, disinfected and the appliance then placed in the patient's mouth [Figure 4], [Figure 5].
The GPI and VAS scores, number of tender muscles, maximum comfortable mouth opening within and between the groups were compared with the help of the student's t-test (paired and unpaired tests). P rd month of treatment follow-up.
Improvement in TMJ tenderness during rest and during movements, and jaw deviation revealed no significant difference between Group A and Group B during the course of the study.
The success for a treatment of any disorder relies on two considerations: relieving of symptoms and treating the cause. In this view, various treatment modalities for TMD have been tried and tested over time. Choosing a specific conservative treatment modality for Myofascial Pain Dysfunction Syndrome patients depends on clinicians' expertise, patient presentation, and elimination of possible etiologic factors. Till date, no single treatment modality has been proven to be better than any other for TMD.
The present study evaluates the efficacy of occlusal splint therapy in the management of MPDS in comparison with pharmacotherapy, both being conservative treatment modalities.
In the current study, 55% of the patients of Group B had complete remission in GPI scores (for disability due to pain), the remaining 45% had significant reduction. TMJ clicking in Group B had also shown significant reduction as compared to Group A during the three months of treatment follow-up. Block et al,  also found that after six weeks of using soft splints, 74% patients had complete or almost complete remission of their TMD symptoms.
In the present study, 11 out of 20 patients (55%) in Group B had complete reduction in muscle tenderness and the remaining nine had significant reduction. Four patients had clicking at the time of diagnosis, which had completely decreased by the third month of treatment follow-up. Kovaleski et al,  have also shown significant reduction in clicking, TMJ and muscle tenderness in response to occlusal splint therapy when patients were followed up for two months. In our study, 70% of the patients showed VAS scores of less than five on a 10-cm continuum scale. Tsuga et al,  concluded that 87% of their patients had reduced TMJ pain; VAS reduction was seen in 50% and clicking was reduced in 70% of the patients. Harkins et al,  found that 74% of the patients with soft splints had reduction in facial myalgia and reduction in or elimination of TMJ clicking. This improvement can be explained by the fact that occlusal splints with equal-intensity contacts on all of the teeth, with immediate disclusion of all posterior teeth by the anterior teeth and condylar guidance in all movements. This will relax the elevator and positioning muscles and contribute to the reduction of abnormal muscle hyperactivity. 
When a splint is inserted, there is an adaptation to a new resting postural position. Occlusal splints that increase the occlusal vertical dimension beyond the freeway space, cause an immediate adaptation to a new freeway space at an increased vertical dimension. Thus, an occlusal splint allows a muscle to function more efficiently during contact and be less active during postural functions. Hence, as the vertical dimension increases from the occlusal contact on the insertion of an occlusal splint, muscular effort decreases resulting in the relaxing of the muscles and hence, the TMJ. 
In the existing study, the VAS scores reduced significantly after pharmacotherapy immediately after seven days of treatment, but the effect was not sustained during three months of treatment follow-up. This is consistent with the study conducted by Minakuchi et al, on the efficacy of occlusal splint therapy and pharmacotherapy on anterior disk displacement without reduction. They showed that both experimental groups had a significant improvement for most of the outcome variables, i.e., maximum mouth opening, VAS of pain and daily activity limitation.  The only group effect seen was with the daily activity limitation variable wherein NSAIDs had a stronger effect than the splint. However, this difference was present only for one month and there were no significant group differences at the completion of the treatment. One probable explanation for this event is that as optimal effects were seen when the concentration of drugs was optimal in the body during treatment. When the therapeutic effects of the drugs wore off, the symptoms reappeared.
In our study, the occlusal splint therapy did not result in any significant reduction in the VAS scores immediately after seven days of treatment, but significant and progressive reduction in VAS scores was seen in the third (last) month of treatment follow-up. This indicates that the occlusal splint causes a slow and steady improvement in TMJ symptoms in comparison to pharmacotherapy. This is in agreement with the conclusions of Raphael et al,  who found that occlusal splints had decreased the VAS scores and the number of painful muscles during a six-week follow-up study in patients with myofascial pain.
In our study, 65% of the patients showed an increase of 10.02 mm improvement in mouth opening with a mean increase of 7.4 mm. Suvinen et al,  have also shown a 7.4 mm improvement in mouth opening after splint therapy. Occlusal splint therapy decreased the pain and tenderness in the muscles and joints of the patients in the present study, apparently allowing an increase in their maximal mouth opening.
Davies et al,  in their study on the pattern of splint usage found no advantage of any particular pattern of splint use (i.e., day/night/day and night-time wear) in patients with myofascial pain dysfunction syndrome. In our study, the patients were instructed to wear the splint during the night to take care of any existing parafunctional habits. Results showed a progressive decrease in GPI and VAS scores, the number of tender muscles and TMJ clicking.
In the present study, the patients in Group B experienced a decrease in the intensity of facial pain and a progressive improvement in TMJ disorder symptoms in comparison to Group A patients. Two patients with symptoms of otalgia and three patients with pain in cervical muscles also improved over a three-month treatment follow-up in Group B patients. This is consistent with the conclusions of Kutilla et al,  who proved the occlusal splint to be beneficial with regard to secondary otalgia and active temporomandibular disorders, facial pain and headache. In our opinion, the improvement of symptoms in these patients may indicate that pain in the auricular area and cervical muscles is often referred pain from the temporomandibular joint and associated structures.
In the current study, 11 out of 20 patients in group B had bruxism, of these 11, eight patients showed significant reduction in parafunctional habits. The other three patients found the occlusal splint to be ineffective in reducing bruxism. Raphael et al,  found an improvement in pain-related measures but the severity of bruxism did not moderate the therapeutic effect of the occlusal splints in their study. This could be explained due to the compressible nature of the soft occlusal splint in patients who are 'dedicated bruxists' and who are so aware of having something compressible in the mouth that they actually increase the activity rather than decrease it. 
Nonsteroidal anti-inflammatory analgesics (NSAIDs) are known to be effective in the management of mild-to-moderate inflammatory conditions, particularly of the musculoskeletal system.  Muscle relaxants are administered to reduce skeletal muscle tone and are often administered to patients with muscle tone and chronic orofacial pain to help prevent or alleviate the increased muscle activity.  They are thought to decrease muscle tone without the impairment of motor function by acting centrally to depress polysynaptic reflexes.
Andrade et al,  have reported pharmacological guidelines for the treatment of TMD. For acute spasm or Myofascial pain, Dypirone 500 mg can be given with a muscle relaxant, three times daily for two days whereas NSAIDs (oral route) can be given for 5-7 days for myositis and TMJ inflammatory disorders. A lack of therapeutic effect after a 7-10 days' trial or the development of any Gastro Intestinal (GI) symptoms should lead to prompt discontinuation of the NSAIDs. 
Due to the lack of standard recommended dosages of any form of pharmacotherapy, a commercially available combination of a muscle relaxant and analgesics consisting of Ibuprofen 400 mg, Paracetamol 325 mg, and Chlorzoxazone 250 mg was administered orally twice a day for 5-7 days initially in the present study. When patients reported with recurrence of pain during their post treatment follow-up, they were advised to repeat the same treatment regimen.
There was no report of serious side effects due to drug intake in any patient. Only four patients reported mild GI symptoms during the follow-up, which subsided after the discontinuation of the drugs. In Group B, a few patients had initial side effects such as dryness of mouth, occasional feeling of tightness of the appliance, and a feeling of queasiness and presence of foreign object, which gradually decreased within few days.
The results of the present study infer that a soft occlusal splint therapy is a commonly used conservative treatment modalities and is useful in the reduction of pain and tenderness in the muscles and also in an improvement in mouth opening. This is in agreement with various studies supporting the usefulness of occlusal splints in the management of Myofascial Pain Dysfunction Syndrome. ,,,,,,,,,,,,,,,,,,,,,
No treatment outcome is completely predictable with any form of therapy. The adverse effects caused by long-term use of various NSAIDs such as nausea, dyspepsia, ulceration, enteropathy, strictures, bleeding and perforations should not be overlooked. It has to be noted that NSAIDs are contraindicated in patients taking anticoagulants, diuretics and in patients with severe renal disease. Therefore, it is always advisable to choose a safer form of therapy in the management of patients with chronic musculoskeletal pain. The present study supports the use of conventional soft occlusal splints in the safe management of patients with myofascial pain dysfunction syndrome. But the present study does have certain limitations like the absence of a control group and of blinding during the evaluation of the patients.
The conventional soft occlusal splint therapy is a much safer and effective mode of a conservative line of therapy in comparison to long-term pharmacotherapy in patients with myofascial pain dysfunction syndrome. The advantages of occlusal splint therapy include reversible therapy, better results, fewer side effects, cost-effectiveness and better patient compliance than pharmacotherapy, which has many adverse side effects. The occlusal splint may also have placebo effects. This study supports the use of occlusal splint therapy in the management of Myofascial Pain Dysfunction Syndrome for better long-term results. Furthermore, randomized blinded trials with appropriate control groups are necessary to validate the effectiveness of occlusal splint therapy in a larger study sample.
The authors would like to acknowledge Dr. C Bhasker Rao, Principal SDM College of Dental Sciences Dharwad for his encouragement and Dr. Renuka J Bathi former Professor and HOD Department of Oral Medicine and Radiology SDM College of Dental Sciences Dharwad for the help rendered towards the study.
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