Efficiency of occlusal splint therapy on orofacial muscle pain reduction: a systematic review.

BACKGROUND: This systematic review aims to examine the existing original studies to determine the effectiveness of occlusal splints (OSs) in the management of orofacial myalgia and myofascial pain (MP) in comparison with no treatment or other interventions. MATERIALS AND METHODS: Based on the inclusion and exclusion criteria of this systematic review, randomized controlled trials were qualified, in which the effectiveness of occlusal splint therapy in the management of muscle pain was examined in comparison with no treatment or other interventions. This systematic review was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020. The authors searched three databases (PubMed, CINAHL (The Cumulative Index to Nursing and Allied Health Literature) and Scopus) for English publications published between January 1, 2010, and June 1, 2022. The last database search was carried out on June 4, 2022. Data were extracted from the included studies and assessed for risk of bias using the revised Cochrane risk-of-bias tool for randomized trials. RESULTS: Thirteen studies were identified for inclusion in this review. In total, 589 patients were diagnosed with orofacial muscle pain who underwent education and various forms of therapy including different types of OSs, light emitting diode therapy, acupuncture, low-level laser therapy, device-supported sensorimotor training, Kinesio Taping, myofunctional therapy, and physical therapy. All studies included demonstrated a high risk of bias. CONCLUSIONS: There is insufficient evidence regarding whether OS therapy in the treatment of orofacial myalgia and MP offers an advantage over other forms of interventions or no treatment. Further reliable clinical studies in this area are needed to improve the quality of research, which should be performed with larger groups of blinded respondents and controls. CLINICAL RELEVANCE: Due to the large-scale nature of orofacial muscle pain, it is assumed that each dental clinician will meet patients with orofacial muscle pain repeatedly in daily practice; hence, the review of the effectiveness of OSs in the management of orofacial myalgia and MP is necessary.

Digitally programmed (CAD) offset values for prototyped occlusal splints (CAM): assessment of appliance-fitting using surface-based superimposition and deviation analysis.

AIM: Limited data are available on the fitting properties of prototyped occlusal appliances. The aim of the present study was to assess the fitting of prototyped splints digitally designed with different offset values and generated with two different biocompatible resins. MATERIALS AND METHODS: Ten dental digital models were included, and occlusal splints were designed with different offset values (0.0, 0.05, 0.10, 0.15, 0.20, and 0.25 mm). Each splint was 3D printed using two different biocompatible resins, and the gap between the splint and the teeth was recorded by placing impression material. A specific 3D technology was used to assess the gap volume between the splint and the teeth and to calculate the Euclidean distance between the surface points of two digital models, with and without the gap volume. RESULTS: The splints with a 0.20-mm offset value showed smaller gap volume and deviation analysis values compared with those with offset values of 0.15 and 0.25 mm (P < 0.05). These results were consistent with both types of biocompatible resins used. For each offset value tested, the gap volume and deviation value analysis did not significantly differ between the splints printed with the two different resins. CONCLUSION: According to the present findings, the 0.20-mm offset value would be the best choice when digitally designing occlusal appliances.

Long-term treatment outcome for adolescents with temporomandibular pain.

OBJECTIVES: This study aims to evaluate long-term, self-perceived outcome in adulthood for individuals treated as adolescents for temporomandibular disorder (TMD) pain in two previous randomized controlled trials (RCTs). MATERIALS AND METHODS: The study included 116 subjects (81% females) treated for frequent TMD pain in two separate RCTs 5-21 (M = 14.8, SD =4.9) years previously. Treatment consisted of occlusal appliance (OA) (n = 41, 35.3%) or relaxation training (RT) combined with information for the control (Co) group (n = 50, 43.1%), both compared to non-responders receiving additional, sequential treatment (ST) in a crossover study (n = 25, 21.6%). Participants answered a questionnaire on their experience of frequency and intensity of TMD pain impaired chewing capacity and daily social activities, help-seeking behaviour and treatment, general health, other pain, and depressive symptoms. RESULTS: Older participants reported lower levels of frequency and intensity of TMD pain, impairment, and depressive symptoms, as well as better general health. Females reported more frequent and more intense TMD pain, greater impairment and more often reported 'other pain' compared to males. Non-responders receiving ST experienced significantly more TMD, and other pain and higher impairment levels compared to other groups. Those treated with an OA had sought additional treatment significantly less often since the RCTs than ST and RT/Co-treated individuals. CONCLUSIONS: Adolescents treated with OA showed somewhat better sustained improvement over the extended follow-up period than those treated with RT/Co. Non-responders to treatment and females exhibited a poorer outcome. These groups need particular attention and extended or different treatments to achieve a better long-term outcome.

Long-term use of occlusal appliance has impact on sleep structure.

Acrylic occlusal appliances (OAs) have been used for temporomandibular disorders and sleep bruxism, but the effects of the treatment are still insufficiently evaluated. Two all-night polysomnographic recordings were made in a sleep laboratory on 14 bruxists (9 females and 5 males with mean age of 27·5 years). The measurement included basic polysomnography with additional masseter muscle electromyogram and movement recording (static charge-sensitive bed method) using randomisation. The base night recording was followed by the second study night after 8 weeks regular use of OA. The OA was made on the occlusal surface of the teeth of the upper jaw, and it was used at night time during the study period. With the OA, rapid eye movement sleep changed from 23·3% to 19·6% (P = 0·078), and slow wave sleep increased significantly from 10·2% to 14·7% (P = 0·039). Masseter contraction (MC) episodes occurred with similar frequency (9·7 vs. 10·5 episodes per hour, P = 0·272). The intensity of the rhythmic MC bursts within an episode decreased from 5·5 to 4·4 (P = 0·027). The groups were post hoc divided into responders and non-responders using a 20% change in MC episode per hour as a cut-off point. The results indicated that 43% of bruxists increased activity (negative responders), while 36% decreased (positive responders), and in 21%, there was no change in the level. It is concluded that OA does not have significant feedback inhibition on masseter muscle motor activity during sleep. However, OA may increase slow wave sleep.

Guidance Prostheses for Partial Mandibulectomy Patients: A Case Series.

This case series discusses the fabrication of guidance prostheses (GPs) for patients who presented to the Department of Prosthodontics with marked mandibular deviation, resulting in facial disfigurement and deranged occlusion. These GPs guide the mandible to the unresected side to achieve stable occlusion. This case series included three approaches to reducing mandibular deviation: a maxillary guidance ramp, a mandibular guidance prosthesis, and a twin occlusal appliance. These approaches were used in conjunction with a well-planned mandibular exercise regimen. The earlier mandibular guidance therapy is started, the better the outcome. GPs are used until good occlusal relationships and proprioception are restored. These GPs can be discarded or used occasionally once a good occlusal relationship has been achieved.

Electromyography-Guided Adjustment of an Occlusal Appliance: Effect on Pain Perceptions Related with Temporomandibular Disorders. A Controlled Clinical Study.

BACKGROUND: The purpose of this study is to evaluate the effect of an electromyography-guided adjustment of an occlusal appliance on the management of Temporomandibular disorder-related pain. METHODS: Data from 40 adult patients (20 males and 20 females), who underwent treatment with occlusal appliances, were recorded. A total of 20 appliances were adjusted according to electromyographic data (group 1), while the others were adjusted by a clinical conventional procedure (group 2). Muscle pain to palpation, pain during articular movements and headache were recorded by a VAS score (from 0 to 100) before the beginning of treatment (T0), at T1 (4 weeks) and T2 (8 weeks). RESULTS: Results showed a reduction of pain in both groups, with a better trend for group 1, where better results were achieved at T1 and maintained stability at T2, with an improved mean value regarding all parameters studied. After 8 weeks, only small recurrences started to occur in muscle pain to palpation in group 2. CONCLUSIONS: An occlusal appliance seems to be able to achieve a clinical improvement of Temporomandibular disorder (TMD)-related pain and headache, independently from the adjustment procedure adopted. However, the use of a surface electromyographic activity of masticatory muscles (sEMG) device as an aid in the calibration procedure seems to allow a better trend because the improvement of symptoms was obtained before, after the first four weeks, with an improvement in percentages of all the variables investigated. While the conventional procedure obtained later the improvement.

Pressure Algometry Evaluation of Two Occlusal Splint Designs in Bruxism Management-Randomized, Controlled Clinical Trial.

The aim of this pilot study was to evaluate the short-term effectiveness of two different occlusal devices and their impact on the pressure pain threshold (PPT) values among patients who reported to the Dental Prosthetics Outpatient Clinic of Pomeranian Medical University (Szczecin, Poland) and who were diagnosed with probable bruxism. Two groups were formed (A and B) to which patients were assigned randomly. Each group used a different occlusal splint for bruxism management. The occlusal appliance by Okeson, or the bimaxillary splint, was used overnight by each patient for 30 days of the study. The PPT was measured twice, at the first visit and after 30 days of using each occlusal device, with Wagner Paintest FPX 25 algometer. Bruxism was diagnosed based on data from the patient's medical history and from the physical examination. Nocturnal Bruxism Criteria according to the International Classification of Sleep Disorders (Third Edition) was used for the patient's evaluation. Results: similar pain factor (PF) reduction was observed in both the examined groups, regardless of the device used; canine guidance and no guidance were similarly effective in terms of increasing pain resilience.

The course of pain intensity and frequency of adolescents treated because of temporomandibular disorders: A long-term follow-up.

OBJECTIVES: To evaluate the course of pain intensity and frequency related to temporomandibular disorders (TMDs) 15 years (range 5-21 years) after having received TMD treatment as adolescents due to frequent (at least once a week) TMD pain in two controlled trials. MATERIALS AND METHODS: In the first trial, subjects (n = 122) were randomly allocated to either information only, received in a control condition (Co), or information and an occlusal appliance (OA) versus relaxation therapy (RT). In the second trial, including 64 subjects, nonresponders to OA or RT were subsequently allocated to the alternate treatment (ST). All study participants having completed the trials (n = 167) were invited to a long-term follow-up evaluations, with a response rate of 69.5% (n = 116). Patient-reported outcomes of TMD-related frequency and intensity were appraised relative to baseline data and short-term outcomes as observed in the two trials by use of general linear mixed model and generalized estimation equation statistics. RESULTS: A significantly higher proportion of participants treated with OA and in the combined RT/Co condition than those in the ST group, reported a frequency level of TMD pain less than once week at post-treatment and the long-term follow-up. Adolescents treated with OA showed significantly lower TMD pain intensity levels post-treatment than those in the other two treatment conditions. While no difference between the OA and the RT/Co conditions was found in the long-term follow-up, participants in these two conditions were significantly more improved than those in the ST group. CONCLUSION: Adolescents treated with an OA clearly showed better outcome with regard to intensity and frequency in a long-term follow-up of TMD pain than those treated with RT and ST for nonresponders. These latter individuals need special clinical attention and more effective supplementary treatment methods to be developed.

Prosthetic management of a masticatory muscle disorder with customized occlusal splint.

Occlusal splints of various types and designs are used in the diagnosis and treatment of different masticatory muscle and TMJ disorders. These appliances or devices provide a relatively simple, reversible and non-invasive form of treatment management. Treating such a disorder is really challenging for both dental and medical specialists and often it is difficult to diagnose as the presenting symptoms can be variable. The present article thus describes a case report on fabrication of simplified customized occlusal splint emphasizing the importance of medico-dental team approach for successful management with occlusal splint therapy.

Después de cien años de uso: ¿las férulas oclusales tienen algún efecto terapéutico? / After a century of use: do the occlusal appliances have any therapeutic effects?

Las férulas o planos oclusales han sido utilizadas desde hace más de un siglo, generando controversia acerca de su verdadero valor terapéutico. Esto motivó una revisión histórica y actualizada que permitiera evaluar sus efectos de acuerdo a la evidencia científica. Se discuten múltiples aspectos como el concepto de relación céntrica y su determinación como punto de inicio de tratamiento en la rehabilitación oral; el uso de las férulas para deprogramar; su efecto sobre la conducta motora oral que conocemos como bruxismo; su efecto en la actividad electromiográfica tónica, durante la deglución y el máximo apriete en los músculos masticatorios y cervicales; su influencia en la eficiencia muscular; su efecto en la carga articular y las evidencias experimentales del uso de distintas férulas sobre signos y síntomas especíicos como dolor y ruido articular. Se plantean desafíos para la investigación sobre cambios degenerativos en las articulaciones, en la relación craneovertebral y en la curvatura e inclinación de la columna cervical. Se concluye que es necesario utilizar una férula diseñada para el trastorno específico del paciente y que su verdadero valor terapéutico queda demostrado al mejorar algunos signos y síntomas, en músculos masticatorios y cervicales. El conocimiento parcial del mecanismo de acción de las férulas contribuye a que persista la controversia de su utilización en el tratamiento de ruidos articulares y para revertir cambios degenerativos en las articulaciones. Persiste el desafío de nuevas investigaciones, que sustenten el uso de estos dispositivos como un método eficaz para tratar a nuestros pacientes, utilizando protocolos de manejo y controles periódicos.

Occlusal appliances or splints have been used for over a century, generating controversy about their real therapeutic value. This led to an updated review to assess their effects according to scientific evidence. The concept of centric relation and its determination as a starting point of treatment; the use of splints to deprogram; their effect on the oral motor behaviour known as bruxism are discussed. Their effect on EMG activity during resting, swallowing and maximal clenching in the masticatory and neck muscles; their effect on muscular eficiency; their effect decreasing the joint overload; and experimental evidence of the use of several appliances on speciic symptoms such as pain and joint noise, are also treated. The true challenge is to generate new knowledge about joint degenerative changes, the craniocervical relationships, tilt and curvature of the cervical spine. In conclusion, it's necessary to use an occlusal appliance designed for the specific condition of the patient, and its real therapeutic value is demonstrated by the improvement of some signs and symptoms in masticatory and cervical muscles. However, the action mechanisms of occlusal appliances are not fully understood. The lack of scientiic support contributes to the persistent controversy of the use of these appliances in the treatment of temporomandibular joint sounds and reversing degenerative changes. It is still a challenge to carry out new researches supporting the use of these appliances as an effective method to treat our patients using management protocols and periodic evaluations.