Behavioural changes and occlusal splints are effective in the management of masticatory myofascial pain: a short-term evaluation

Summary The aim of this research was to test the hypothesis that treatment with intra‐oral appliances with different occlusal designs was beneficial in the management of pain of masticatory muscles compared with a control group. A total of 51 patients were analysed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) to obtain the diagnosis of masticatory myofascial pain (MMP). The sample was then randomly divided into three groups: group I (n = 21) wore a full coverage acrylic stabilisation occlusal splint; group II (n = 16) wore an anterior device nociceptive trigeminal inhibitory (NTI) system; and group III (n = 14) only received counselling for behavioural changes and self‐care (the control group). The first two groups also received counselling. Follow‐ups were performed after 2 and 6 weeks and 3 months. In these sessions, patients were evaluated by means of a visual analogue scale (VAS) and pressure pain threshold (PPT) of the masticatory muscles. Possible adverse effects were also recorded, such as discomfort while using the appliance and occlusal changes. The results were analysed with Kruskal–Wallis, anova , Tukey’s and Friedman tests, with a significance level of 5%. Group I showed improvement in the reported pain at the first follow‐up (2 weeks), whereas for groups II and III, this progress was detected only after 6 weeks and 3 months, respectively. The PPT values did not change significantly. It was concluded that behavioural changes are effective in the management of pain in MMP patients. However, the simultaneous use of occlusal devices appears to produce an earlier improvement.     

Comparison of device‐supported sensorimotor training and splint intervention for myofascial temporomandibular disorder pain patients

This study was to compare the short‐term therapeutic efficacy of device‐supported sensorimotor training with that of standard splint therapy for patients with myofascial temporomandibular disorder (TMD) pain over a treatment period of 3 months. We tested the hypothesis that both types of intervention are equally effective for pain reduction. In addition, the electromyographic (EMG) activity of the temporal and masseter muscles was recorded under conditions of force‐controlled submaximum and maximum biting in intercuspation. Of consecutive patients seeking treatment for non‐odontogenic oro‐facial pain, 45 patients with myofascial TMD pain (graded chronic pain status, GCPS, I and II) were randomly assigned to 2 treatment groups (sensorimotor training and conventional splint treatment). Patients were evaluated 4 times (initial examination, 2, 6 and 12 weeks later) by use of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Electromyographic activity was recorded at the initial session and after 3 months. Ease‐of‐use of the treatment options was also evaluated. Significant (P < .0001) pain reduction (sensorimotor training 53%, splint therapy 40%) was achieved for both groups, with no significant differences (P > .05) between the groups. Force‐controlled sub‐maximum normalized electromyographic activity was significantly different between T0 and T3 for group A (sensorimotor training, P < .05) but was not significantly different for group B (splint, P > .05). For normalized maximum‐biting EMG activity in intercuspation, however, a significant increase in EMG activity was observed for group A for the masseter and temporal muscles (P < .001) and for group B for the masseter muscle only (P < .001). Moreover, sensorimotor training was significantly (P < .05) less easy to use than the splint. The results of this study confirm the pain‐reducing effect of sensorimotor training for patients with myofascial TMD pain (GCPS I and II). This innovative active treatment might be a promising option for TMD pain patients.     

Evaluation of the short-term effectiveness of education versus an occlusal splint for the treatment of myofascial pain of the jaw muscles

BackgroundThe authors conducted a clinical trial to compare the effectiveness of an education program with that of an occlusal splint in treating myofascial pain of the jaw muscles across a short period.MethodThe authors assigned 44 patients randomly to two treatment groups; 41 patients completed the study. The first group (four male, 19 female; mean [standard deviation {SD}] age, 31.4 [14.0] years) received information regarding the nature of temporomandibular disorder (TMD) and self-care measures, whereas the second group (five male, 13 female; mean [SD] age, 31.1 [8.8] years) received an occlusal splint. One of the authors evaluated each patient every three weeks during a three-month treatment period. Treatment outcomes included pain-free maximal mouth opening, spontaneous muscle pain, pain during chewing and headache.ResultsAfter three months, changes in spontaneous muscle pain differed significantly between the education and occlusal splint groups (P = .034; effect size = 0.33). Changes in pain-free maximal mouth opening did not differ significantly between groups (P = .528; effect size = 0.20). Changes of headache and pain on chewing did not differ significantly between groups (P ≥ .550, effect size ≤ 0.10).ConclusionsDuring a short period, education was slightly more effective than an occlusal splint delivered without education in reducing spontaneous muscle pain in patients with TMD. Pain-free mouth opening, headache and pain during chewing were not significantly different between the two treatments.     

The hemodynamic effects of occlusal splint therapy on the masseter muscle of patients with myofascial pain accompanied by bruxism

ABSTRACT

Objective: The aim of this study was to investigate the hemodynamic effects of occlusal splint therapy on masseter muscles of patients with myofascial pain accompanied by bruxism with near-infrared spectroscopy (NIRS).

Methods: Twenty-four patients were randomly divided into two groups, where the study group (n = 12) received occlusal splint therapy and the control group (n = 12) underwent no therapy. Measurements were categorized into four subgroups: painful or painless control and painful or painless splint. Percent changes in deoxyhemoglobin (Hb), oxyhemoglobin (HbO₂), and OXY (HbO₂-Hb) values were calculated during a 1-month period.

Results: Statistically significant inter-session differences between painful-splint and painful-control groups were detected for NIRS oxygenation parameters, whereas inter-session differences between painless groups were statistically insignificant.

Conclusion: The results suggest that occlusal splint usage causes a decrease in hyperemic response, which is indicative of a decrease in masseter muscle contraction strength.     

A change of occlusal conditions after splint therapy for bruxers with and without pain in the masticatory muscles

Bruxism has been suggested as an initiating or perpetuating factor in a certain subgroup of temporomandibular disorders (TMD), however, the exact association between bruxism and TMD remains unclear. This study aimed to demonstrate the difference in responses between bruxism and a subgroup of TMD to a full-arch maxillary stabilization splint from the standpoint of an occlusal condition. This study was conducted to verify the null hypothesis that there were no differences between bruxer groups with and without myofascial pain (MFP) with respect to the changes in occlusal conditions after the use of a splint. Thirty bruxers with MFP and 30 without MFP participated. Occlusal conditions were examined before and after splint therapy, and occlusal changes following the use of a splint were compared between the two groups. The frequency of occlusal changes after splint therapy was significantly higher in the MFP bruxer group than the non-MFP bruxer group (p < 0.05) for the occlusal conditions investigated in the present study. However, no statistical differences were found with regard to each occlusal condition. This result may show the variety of splint effects and may demonstrate a heterogeneous aspect to bruxism and myofascial pain.     

Effect of treatment with a full-occlusion biofeedback splint on sleep bruxism and TMD pain: a randomized controlled clinical trial

Objectives

The purpose of the present study was to analyze treatment outcome with a full-occlusion biofeedback (BFB) splint on sleep bruxism (SB) and TMD pain compared with treatment with an adjusted occlusal splint (AOS).

Materials and methods

Forty-one patients were randomly allocated to a test (BFB) or a control (AOS) group and monitored over a 3-month period. Output variables were frequency and duration of bruxing events (bursts) and various pain symptoms.

Results

The BFB group showed a statistically significant reduction in the frequency and duration of bursts and a statistically significant improvement in the patients’ global well-being and the facial muscle pain parameter. After the treatment was stopped, the BFB group showed a statistically significant reduction in the average and maximum duration but no statistically significant change in the frequency of bursts.

Conclusions

The tested BFB splint is highly effective in reducing SB at the subconscious level, i.e., without waking the patient, and in achieving improvements in global pain perception. The results suggest that the BFB splint also provides a better treatment option for bruxism-related pain than an AOS. However, further research is needed, and specifically studies with a larger patient population displaying higher levels of pain at baseline.

Clinical relevance

By reducing burst duration and therefore the pathological load on the masticatory apparatus, the BFB splint reduces TMD and bruxism-related symptoms and improves patients’ physical well-being. In the long term, this could prevent damage to the TMJ. This study confirms the effectiveness and safety of this splint.

The universal trial number

U1111-1239-2450

DRKS-ID registration

DRKS00018092

     

稳定型咬合板配合咬合重建治疗咀嚼肌疼痛疗效评价

目的　评价稳定型咬合板配合咬合重建治疗咀嚼肌疼痛的疗效。方法　选取2016年9月至2018年5月于中国医科大学附属口腔医院综合科及修复一科行稳定型咬合板及咬合重建序列治疗的咀嚼肌疼痛患者20例。分析治疗前（T0期）、佩戴咬合板3个月后（T1期）、咬合重建完成即刻（T2期）及咬合重建完成3个月后（T3期）的疼痛视觉模拟评分（visual analogue scale,VAS）、肌电图及Friction颞下颌关节紊乱指数的变化。结果　T1、T2、T3期患者VAS评分、下颌姿势位时颞肌咬肌的肌电活性、颞肌咬肌不对称指数及Friction颞下颌关节紊乱指数均较T0期显著降低,差异有统计学意义（均P < 0.05）;最大紧咬牙时颞肌咬肌的肌电活性较T0期明显增高,差异有统计学意义（均P < 0.05）。T1、T2、T3期患者之间的VAS评分、颞肌咬肌的肌电活性、颞肌咬肌不对称指数及Friction颞下颌关节紊乱指数差异无统计学意义（均P > 0.05）。结论　稳定型咬合板可有效治疗咀嚼肌疼痛,咬合重建序列治疗能很好维持其疗效。     

Efficacy of Appliance Therapy on Temporomandibular Disorder Related Facial Pain and Mandibular Mobility: A Randomized Controlled Study

There is limited evidence supporting the role of occlusal splints in Temporomandibular disorder (TMD) therapy. The aim of this randomized controlled clinical trial was to assess the efficacy of stabilization splint therapy on TMD related facial pain and mandibular mobility. The sample of study consisted of eighty consecutive patients diagnosed with TMD. Patients were randomly assigned into two groups: a splint group (n = 40) comprising of patients treated with stabilization splint, councelling and masticatory muscle exercises, and a control group (n = 40), comprising of patients treated with councelling and masticatory muscle exercises alone. Data from both the groups were collected at the beginning of the study and after a 6-month follow up. The outcome variables were visual analogue scale on facial pain intensity and clinical findings for TMD (anterior maximal opening, mandibular right laterotrusion, mandibular left laterotrusion, mandibular protrusion, and number of painful muscle sites). Changes within the splint and control groups (before treatment and 6 months after treatment) were analyzed using paired samples t test. Differences in change between the splint and control groups were analyzed using independent samples t-test. The level of significance was set at p < 0.05. Facial pain and number of painful muscle sites decreased, and the mandibular mobility increased significantly in both groups after treatment; however the differences in changes in VAS or clinical TMD findings between the two groups were not statistically significant. The findings of this study show that stabilization splint treatment in combination with counselling and masticatory muscle exercises has no additional benefit in relieving facial pain and increasing the mobility of the mandible than counselling and masticatory muscle exercises alone over a 6-months’ time interval.     

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??Objective??To observe and analyze the clinical effect of the stabilization splint and the occlusal reconstruction treatment on patients with masticatory muscle pain. Methods??Totally 20 patients with masticatory muscle pain who visited General Department and Prosthodontics Department of Affiliated Stomatology Hospital of China Medical University from September 2016 to May 2018 were given the stabilization splint therapy and the occlusal reconstruction treatment. Analyze the visual analogue scale??VAS????electromyographic pattern and Friction temporomandibular joint dysfunction index before treatment??T0????three months after the stabilization splint therapy??T1????when occlusal reconstruction was finished??T2??and three months later??T3??. Results??Statistical analysis showed that VAS??the electromyographic signal of anterior temporalis and masseters in mandibular postural position??asymmetry index of masseter muscles and temporalis muscles and Friction temporomandibular joint dysfunction index in T1??T2 and T3 were significantly lower than those in T0??P < 0.05??. The electromyographic signal were dramatically increased in intercuspal position ??P < 0.05??. No significant difference was shown in VAS??the electromyographic signal of anterior temporalis and masseters??asymmetry index of masseter muscles and temporalis muscles??or Friction temporomandibular joint dysfunction index in T1??T2 and T3??P > 0.05??. Conclusion??The stabilization splint therapy is effective on patients with masticatory muscle pain??and the occlusal reconstruction treatment is able to maintain these effects.     

咬合板高度对TMD患者咀嚼肌肌电的影响

目的:研究不同高度的咬合板对颞下颌关节紊乱病(TMD)患者颞肌前束、咬肌肌电的影响。方法:73例TMD患者随机分为3组,戴用不同高度咬合板使咬合距离分别增加3mm、5mm、7mm,比较分析戴板前和戴板后即刻测量的双侧颞肌前束(TA)和咬肌(MM)肌电电位。结果:在静息及紧咬状态下,戴用不同高度咬合板即刻测量的TA及MM肌电电位均明显低于戴板前的测量值(P<0.05);紧咬状态下5mm和7mm咬合板对MM肌电电位的降低程度显著高于3mm组。结论:咬合板是治疗肌功能紊乱的有效方法。高度为5mm和7mm的咬合板降低咀嚼肌肌电的能力较3mm咬合板更强。     

Efficacy of stabilisation splint treatment on facial pain – 1‐year follow‐up

The aim of this randomised controlled trial was to assess the efficacy of stabilisation splint treatment on TMD‐related facial pain during a 1‐year follow‐up. Eighty patients were randomly assigned to two groups: splint group (n = 39) and control group (n = 41). The patients in the splint group were treated with a stabilisation splint and received counselling and instructions for masticatory muscle exercises. The controls received only counselling and instructions for masticatory muscles exercises. The outcome variables were the change in the intensity of facial pain (as measured with visual analogue scale, VAS) as well as the patients' subjective estimate of treatment outcome. The differences in VAS changes between the groups were analysed using variance analysis and linear regression models. The VAS decreased in both groups, the difference between the groups being not statistically significant. The group status did not significantly associate with the decrease in VAS after adjustment for baseline VAS, gender, age, length of treatment and general health status. The only statistically significant predicting factor was the baseline VAS, which was also confirmed by the mixed‐effect linear model. After 1‐year follow‐up, 27·6% of the patients in the splint group and 37·5% of the patients in the control group reported ‘very good' treatment effects. The findings of this study did not show stabilisation splint treatment to be more effective in decreasing facial pain than masticatory muscle exercises and counselling alone in the treatment of TMD‐related facial pain over a 1‐year follow‐up.     

The association between forward head posture and masticatory muscle pressure pain thresholds in patients with temporomandibular joint dissorders: a cross-sectional observational study

Objectives

Forward head posture (FHP) is common in patients with temporomandibular joint disorders (TMDs); however, whether it contributes to TMD symptoms remains unclear. The aim of this study was to investigate the association between (1) FHP and masticatory muscle pressure pain thresholds (PPTs) and (2) neck muscle and masticatory muscle PPTs.

Materials and methods

A total of 145 patients diagnosed with TMD were recruited between December 2020 and April 2021. Data regarding FHP and neck and masticatory muscle PPTs were collected. FHP was characterized by the craniocervical angle (CVA) measured between the horizontal line through C7 and the line between the tragus of the ear and C7. Patients were divided into either the FHP group (CVA?≤?51°) or the non-FHP group. Differences in the masseter and temporalis muscle PPTs between the two groups were analyzed using the Mann‐Whitney U test. The correlation between the CVA, neck, and masticatory muscle PPTs in all patients was determined by Spearman’s correlation analysis.

Results

There were 70 patients in the FHP group and 75 patients in the non-FHP group. No significant difference in masseter and temporalis muscle PPTs was found between the two groups (p?>?0.05). No correlation was found between FHP and masticatory muscle PPTs (p?>?0.05). A significant association was found between the neck muscle and masticatory muscle PPTs (p?<?0.05). The C5–C6 pillar and masticatory PPTs were either moderately (r?=?0.435, masseter muscle) or strongly (r?=?0.608, temporalis muscle) correlated, while the correlation between the trapezius and masticatory muscles was moderate (r?=?0.378, masseter muscle and r?=?0.461, temporalis muscle).

Conclusion

FHP was not directly associated with masticatory muscle PPTs. Masticatory muscle PPTs were strongly or moderately associated with neck muscle PPTs. Therefore, the presence of neck pain, not the degree of FHP, in patients with TMD is of significance.

Clinical relevance

In TMD treatment, we should pay attention to and actively relieve neck pain.

     

Management of pain in TMD patients: Bio-oxidative ozone therapy versus occlusal splints

Objective: To compare the effects of bio-oxidative ozone application with occlusal splints in temporomandibular disorder (TMD) patients with pain.

Methods: Forty participants were selected after the diagnosis of TMD and randomly divided into two groups: ozone group (OG, n = 20) and occlusal splint group (OCSG, n = 20). Ozone was applied to patients three times per week, for a total of six sessions. Patients in the OCSG were instructed to use occlusal splints every night over a period of four weeks.

Results: Mandibular movements showed significant differences for the time factor in OG and OCSG. Pressure pain thresholds of the temporal and masseter muscles at follow-up were significantly higher in the OCSG group. Both treatments statistically decreased the visual analog scale (VAS) scores. However, no statistically significant difference was observed between groups after the application of treatments.

Discussion: Occlusal splint treatment is still the gold treatment modality for objective pain relief in patients with TMD pain.     

Efficacy of stabilisation splint treatment on temporomandibular disorders

Summary The evidence supporting the use of stabilisation splints in the treatment of temporomandibular disorders (TMD) is scarce and a need for well‐controlled studies exists. The aim of this randomised, controlled trial study was to assess the efficacy of stabilisation splint treatment on TMD. The sample consisted of 80 consecutive referred patients who were randomly assigned to the splint group (n = 39) and the control group (n = 41). Subjects in the splint group were treated with a stabilisation splint, whereas subjects in the control group did not receive any treatment except counselling and instructions for masticatory muscle exercises which were given also to the subjects in the splint group. Outcomes were visual analogue scale (VAS) on facial pain intensity and clinical findings for TMD which were measured at baseline and after 1‐month follow‐up. The differences in change between the groups were analysed using regression models. Facial pain decreased and most of the clinical TMD findings resolved in both of the groups. The differences in changes in VAS or clinical TMD findings between the groups were not statistically significant. The findings of this study did not show that stabilisation splint treatment in combination with counselling and masticatory muscle exercises has additional benefit in relieving facial pain and increasing the mobility of the mandible than counselling and masticatory muscle exercises alone in a short time‐interval.     

稳定型咬合板治疗颞下颌关节紊乱病疼痛症状的研究

目的：探讨稳定型咬合板治疗颞下颌关节紊乱病（TMD）疼痛的疗效。方法：TMD疼痛患者61例，急性组28例（男11例，女17例）；慢性组33例（男18例，女15例）。记录治疗前后疼痛指数，双侧颞肌前束（temporal anterior，TA）和咬肌（masseter muscle，MM）牙尖交错位最大紧咬时电位及最大紧咬时咬合接触情况。结果：（1）2组治疗后1月疼痛指数均明显低于治疗前（P〈0．05），治疗前后疼痛强度差值及显效率2组之间无显著差异（P〉0．05）。（2）治疗后无论是急性组还是慢性组TA及MM最大紧咬电位症状侧均较治疗前明显升高（P〈0．05），而非症状侧治疗前后无明显差异（P〉0．05）。（3）治疗后急性组TA和MM肌电不对称指数与治疗前相比均明显降低（P〈0．05）。治疗后肌电不对称指数TA慢性组明显高于急性组（P〈0．05），而MM无明显差异（P〉0．05）。（4）2组治疗前后左、右两侧咬合接触点数、以及咬合接触不对称指数无明显差异（P〉0．05）。结论：稳定型咬合板治疗可以明显缓解TMD疼痛，但对急、慢性疼痛的缓解程度无明显差异。其机制可能与肌功能活动情况易于得到明显改善等生理学基础有关。     

Treatment outcome of appliance therapy in temporomandibular disorder patients with myofascial pain after 6 and 12 months

Aim: To compare the long‐term effect of treatment with a stabilization appliance (group T) and treatment with a control appliance (group C) in temporomandibular disorder (TMD) patients with myofascial pain. Methods: In this controlled trial, 60 patients (mean age 29 years) with myofascial pain were evaluated after 10 weeks of treatment with either a stabilization appliance or a control appliance. All 60 patients were then assigned to 1 of 3 groups according to demand for treatment. Seventeen patients from group C requested another appliance and were given a stabilization appliance, thus creating a mixed group (group M). Results: A significant difference in improvement of overall subjective symptoms in an intent‐to‐treat analysis between groups T and C was found at the follow‐ups. In a survival analysis of treatment compliance, a significant difference was found between groups T and C. At the 6‐ and 12‐month follow‐ups, a significant reduction in myofascial pain, as measured on a visual analog scale, was found in all three groups. A significant decrease in frequency and intensity of myofascial pain was found in group T at the follow‐ups. A significant decrease in number of tender sites on the masticatory muscles was found in group T at the follow‐ups. Conclusion: The results support the conclusion that the positive treatment outcome obtained by use of a stabilization appliance to alleviate the signs and symptoms in patients with myofascial pain persisted after 6 and 12 months. Most patients in groups T and M reported positive changes in overall subjective symptoms in this trial. We therefore recommend use of the stabilization appliance in the treatment of TMD patients with myofascial pain.     

Effect of orthognathic surgery on masticatory performance and muscle activity in skeletal Class III patients

Objective: To evaluate the effect of double jaw orthognathic surgery (OGS) on masticatory performance and electromyographic activity of the masseter and anterior temporal muscles in skeletal Class III patients.

Methods: Individuals were instructed to chew standardized round tablets of silicone impression material. The cumulative weight percentage was calculated using sieve analysis. The bilateral surface electromyographic activity of the muscles was evaluated. Following the orthodontic treatment, a stabilization splint was fabricated. Patients were instructed to wear it full-time until the surgical procedure occurred. Recordings were performed before the splint application (T0), after the splint application (T1), 1 month after the OGS (T2), and 6–8 months after the OGS (T3).

Results: Median particle size of the chewed silicone material did not differ from T0 to T1 with the use of an occlusal splint (p > 0.05). However, it decreased from 9.46 to 6.92 cm from T2 to T3. From T0 to T3, a statistically significant decrease was found, following the surgical intervention (p < 0.01). A significant decrease in masticatory muscle activity was also observed during the relaxation test from T0 to T3, at which time it reached the control group value.

Discussion: OGS enhanced masticatory function by improving occlusion in individuals with a dentofacial deformity.     

Effect of muscle relaxation splint therapy on the electromyographic activities of masseter and anterior temporalis muscles

The purpose of this study was to compare the effectiveness of splint therapy on the electromyographic activity of masticatory muscles (anterior temporalis and masseter) before and after the application of a muscle relaxation splint. Electromyography recordings from the masseter and anterior temporalis muscles were analyzed quantitatively during maximal biting in the intercuspal position both before and after treatment without a splint. Fourteen patients whose chief complaint was masticatory muscle pain were selected for the study. After the initial evaluations muscle relaxation splints were applied, and the patients were instructed to use the splints for 6 weeks. Surface electromyographic recordings were taken from each patient before the beginning of clinical therapy and after 6 weeks of wearing the splints. The data obtained were analyzed through paired sample t tests and Wilcoxon's signed rank tests. The results of the study were as follows: (1) the electromyographic activity of the two muscles during maximal biting was not markedly changed after the muscle relaxation splint was used; and (2) the changes observed in electromyographic activity of the involved and noninvolved sides were insignificant as well.     

Are the bite force and electromyographic activity altered in muscle TMD patients with abfraction lesions?

Objective: To verify if the maximal molar bite force (BF) and the electromyographic activity (EMG) are altered in TMD patients with abfraction lesions (AL) when compared to those without AL.

Methods: The sample was composed of 45 patients (18–60 years old), 30 diagnosed with TMD (RDC/TMD) (15 with AL and 15 without AL) and 15 controls. The BF and the EMG of the masticatory muscles (maximal voluntary contraction (MVC) and chewing gum) were measured.

Results: TMD patients showed decreased BF (p < 0.001), without differences between patients with and without AL. The electromyographic activity during MVC was similar among all groups (p > 0.05), although there was a greater trend of muscular balance for the control group (percentage overlapping coefficient and electromyographic indexes). The TMD group without AL showed a lower number of cycles and masticatory frequency.

Discussion: TMD patients with and without AL exhibited similar results in the analysis of the BF and EMG, without differences.