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BMC Sports Science, Medicine &... May 2024Temporomandibular joint disorder (TMD) is a common condition affecting the masticatory muscles and joint mobility.
BACKGROUND
Temporomandibular joint disorder (TMD) is a common condition affecting the masticatory muscles and joint mobility.
OBJECTIVES
The primary objective was to compare the effects of massage therapy alone and massage therapy combined with post-isometric relaxation exercises in patients with TMD for pain and maximal mouth opening.
DESIGN
Assessor-blinded randomized controlled trial.
SETTING
Sir Ganga Ram Hospital, Chaudhry Muhammad Akram Dental Hospital, Lahore Medical and Dental Hospital.
SUBJECTS
Temporomandibular joint disorder patients.
INTERVENTION
Group A (n = 23) received conventional treatment including massage and therapeutic exercises consecutively for 2 weeks. Group B (n = 23) received post-isometric relaxation technique along with conventional treatment for consecutive 2 weeks.
MAIN MEASURES
The main outcome measures were pain and maximal mouth opening. Pain was measured using the Visual Analogue Scale (VAS) and maximal mouth opening (MMO) was measured using the TheraBite Scale.
RESULTS
Both groups demonstrated significant improvements in pain and MMO scores post-treatment. However, Group B (massage with post-isometric relaxation exercises) showed significantly better outcomes compared to Group A (massage alone). There was a statistically significant difference in post-treatment pain scores (P = 0.000) and MMO scores (P = 0.000) between the two groups.
CONCLUSION
The results suggest that massage therapy combined with post-isometric relaxation is more effective than massage therapy alone in managing pain and improving mouth opening in TMD patients. The study provides evidence supporting the use of these therapies in TMD management.
TRIAL REGISTRY NUMBER
NCT05810831. Date of registration/First submission: 15 March 2023.
PubMed: 38750518
DOI: 10.1186/s13102-024-00865-x -
BMC Oral Health May 2024The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection...
BACKGROUND
The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection between probable sleep bruxism, electromyographic muscle tone, and respiratory sleep patterns recorded during polysomnography.
METHODS
106 patients with OSA (74 males, 31 females, mean age: 56.1 ± 11.4 years) were divided into two groups (sleep bruxism: SB; no sleep bruxism: NSB). Probable SB were based on the AASM criteria: self-report of clenching/grinding, orofacial symptoms upon awakening, abnormal tooth wear and hypertrophy of the masseter muscle. Both groups underwent clinical examination for painful muscle symptoms aligned with Temporomandibular Disorders Diagnostic Criteria (DC/TMD), such as myalgia, myofascial pain, and headache attributed to temporomandibular disorder. Additionally, non-complaint positive muscle palpation and orofacial-related limitations (Jaw Functional Limited Scale-20: JFLS-20) were assessed. A one-night polysomnography with electromyographic masseter muscle tone (EMG) measurement was performed. Descriptive data, inter-group comparisons and multivariate logistic regression were calculated.
RESULTS
OSA patients had a 37.1% prevalence of SB. EMG muscle tone (N1-N3, REM; P = 0.001) and the number of hypopneas (P = 0.042) were significantly higher in the sleep bruxism group. While measures like apnea-hypopnea-index (AHI), respiratory-disturbance-index (RDI), apnea index (AI), hypopnea-index (HI), number of arousals, and heart rate (1/min) were elevated in sleep bruxers, the differences were not statistically significant. There was no difference in sleep efficiency (SE; P = 0.403). Non-complaint masseter muscle palpation (61.5%; P = 0.015) and myalgia (41%; P = 0.010) were significant higher in SB patients. Multivariate logistic regression showed a significant contribution of EMG muscle tone and JFLS-20 to bruxism risk.
CONCLUSION
Increased EMG muscle tone and orofacial limitations can predict sleep bruxism in OSA patients. Besides, SB patients suffer more from sleep disorder breathing. Thus, sleep bruxism seems to be not only an oral health related problem in obstructive apnea. Consequently, interdisciplinary interventions are crucial for effectively treating these patients.
TRIAL REGISTRATION
The study was approved by the Ethics Committee of Philipps-University Marburg (reg. no. 13/22-2022) and registered at the "German Clinical Trial Register, DRKS" (DRKS0002959).
Topics: Humans; Male; Female; Sleep Apnea, Obstructive; Sleep Bruxism; Middle Aged; Electromyography; Prospective Studies; Polysomnography; Masseter Muscle; Oral Health; Adult; Muscle Tonus
PubMed: 38745301
DOI: 10.1186/s12903-024-04351-1 -
BMC Oral Health May 2024Patients who suffer from myofascial orofacial pain could affect their quality of life deeply. The pathogenesis of pain is still unclear. Our objective was to assess...
Patients who suffer from myofascial orofacial pain could affect their quality of life deeply. The pathogenesis of pain is still unclear. Our objective was to assess Whether Voltage-gated calcium channel αδ-1(Cavα2δ-1) is related to myofascial orofacial pain. Rats were divided into the masseter tendon ligation group and the sham group. Compared with the sham group, the mechanical pain threshold of the masseter tendon ligation group was reduced on the 4th, 7th, 10th and 14th day after operation(P < 0.05). On the 14th day after operation, Cavα2δ-1 mRNA expression levels in trigeminal ganglion (TG) and the trigeminal spinal subnucleus caudalis and C1-C2 spinal cervical dorsal horn (Vc/C) of the masseter tendon ligation group were increased (P=0.021, P=0.012). Rats were divided into three groups. On the 4th day after ligating the superficial tendon of the left masseter muscle of the rats, 10 ul Cavα2δ-1 antisense oligonucleotide, 10 ul Cavα2δ-1 mismatched oligonucleotides and 10 ul normal saline was separately injected into the left masseter muscle of rats in Cavα2δ-1 antisense oligonucleotide group, Cavα2δ-1 mismatched oligonucleotides group and normal saline control group twice a day for 4 days. The mechanical pain threshold of the Cavα2δ-1 antisense oligonucleotides group was higher than Cavα2δ-1 mismatched oligonucleotides group on the 7th and 10th day after operation (P < 0.01). After PC12 cells were treated with lipopolysaccharide, Cavα2δ-1 mRNA expression level increased (P < 0.001). Cavα2δ-1 may be involved in the occurrence and development in myofascial orofacial pain.
Topics: Animals; Rats; Masseter Muscle; Male; Rats, Sprague-Dawley; Calcium Channels; Trigeminal Ganglion; Pain Threshold; Facial Pain; Spinal Cord Dorsal Horn; Oligonucleotides, Antisense; Myofascial Pain Syndromes; RNA, Messenger; Calcium Channels, L-Type
PubMed: 38735923
DOI: 10.1186/s12903-024-04338-y -
Animals : An Open Access Journal From... May 2024The aim of this study was to analyse the bite forces of seven species from three carnivore families: Canidae, Felidae, and Ursidae. The material consisted of complete,...
The aim of this study was to analyse the bite forces of seven species from three carnivore families: Canidae, Felidae, and Ursidae. The material consisted of complete, dry crania and mandibles. A total of 33 measurements were taken on each skull, mandible, temporomandibular joint, and teeth. The area of the temporalis and masseter muscles was calculated, as was the length of the arms of the forces acting on them. Based on the results, the bite force was calculated using a mathematical lever model. This study compared the estimated areas of the masticatory muscles and the bending strength of the upper canines among seven species. A strong correlation was found between cranial size and bite force. The results confirmed the hypothesis that the weight of the animal and the size of the skull have a significant effect on the bite force.
PubMed: 38731371
DOI: 10.3390/ani14091367 -
Cureus May 2024Background This study aimed to determine if individuals with skeletal Class II and skeletal Class III malocclusions had different levels of masticatory muscle activity....
Background This study aimed to determine if individuals with skeletal Class II and skeletal Class III malocclusions had different levels of masticatory muscle activity. Materials and methods This cross-sectional study, conducted at the University of Damascus, investigated the myoelectric activity of perioral muscles in patients with Class II and III malocclusions. The sample size of 60 patients was determined according to a prior sample size calculation. Patients were selected based on specific inclusion and exclusion criteria and divided into Class II and III groups. Electromyography was used to monitor the activity of various muscles, including the temporalis, masseter, orbicularis oris, buccinator, mentalis, and digastric muscles. Results The study found similar muscle activity within the same group in the temporalis, masseter, buccinator, digastric, and orbicularis oris muscles. No significant differences were observed between the Class II and III groups for several oral and perioral muscles (P > 0.05). However, the mean activity of the digastric muscle was significantly greater in the Class II group (P < 0.05), whereas the mean activity of the mentalis muscle was smaller in the Class II group (P < 0.05). Conclusions Perioral muscles influence facial complex development and jaw relationship, affecting orthodontic treatment. Digastric muscle activity is greater in Class II patients, while mental muscle activity is smaller in Class III patients. Further studies are needed for older age groups and other skeletal malocclusion types.
PubMed: 38726355
DOI: 10.7759/cureus.59861 -
Clinical Oral Investigations May 2024Total tooth loss is common in the aging population resulting in insufficient chewing function with subsequent weakening of the masticatory muscles. The study aims to...
OBJECTIVES
Total tooth loss is common in the aging population resulting in insufficient chewing function with subsequent weakening of the masticatory muscles. The study aims to evaluate the changes in thicknesses of the masseter and anterior temporal muscle in edentulous patients following the reconstruction of implant-supported fixed prostheses and compare them with the dentate individuals.
MATERIALS AND METHODS
The study was designed as a prospective, single-center, controlled clinical trial. A total of 60 participants were included in the present study. The patients were divided into two groups; Group I (Test Group): 30 edentulous patients who received implant-supported fixed prostheses, Group II (Control Group): 30 dentate individuals of an age and sex-matched group. Ultrasonography was used to measure the cross-sectional thickness of the left and right musculus masseter and anterior temporalis immediately after the cementation of the prosthetic rehabilitation (T1), on the 1st (T2) and 6th (T3) months after rehabilitation and at a single time point in the control group.
RESULTS
The results showed that there were significant comparison differences in muscle thickness at the baseline measurements between groups while at the end of the 6th month, these differences were not significant. The muscle thicknesses of both the masseter and anterior temporalis muscles increased significantly at T2 and T3 compared to T1 in the test group. The asymmetry index between the left and right muscles in the test group and the asymmetry differences between groups also decreased significantly at the end of the 6th month.
CONCLUSION
The implant-supported fixed prostheses significantly increase the thicknesses of the masseter and anterior temporal muscle together with a decrease in the asymmetry between the left and right muscles. At six months, implant-treated patients showed similar muscle thicknesses compared to dentate individuals.
CLINICAL RELEVANCE
The findings suggest that implant-supported fixed prostheses can improve the masticatory function and facial symmetry of edentulous patients.
Topics: Humans; Male; Female; Prospective Studies; Dental Prosthesis, Implant-Supported; Masseter Muscle; Temporal Muscle; Middle Aged; Ultrasonography; Mouth, Edentulous; Aged; Treatment Outcome
PubMed: 38722451
DOI: 10.1007/s00784-024-05676-5 -
The Journal of Prosthetic Dentistry May 2024Transcutaneous electrical nerve stimulation (TENS) has been used in several clinical areas. However, the effect of TENS on the masticatory muscles of young individuals...
STATEMENT OF PROBLEM
Transcutaneous electrical nerve stimulation (TENS) has been used in several clinical areas. However, the effect of TENS on the masticatory muscles of young individuals with normal occlusion remains unclear.
PURPOSE
The purpose of the study was to assess the effect of TENS on the surface electromyographic (sEMG) activity of masticatory muscles in a young population with normal occlusion.
MATERIAL AND METHODS
Twenty residents (5 men and 15 women, mean 24.27 ±2.59 years) of Dalian Stomatological Hospital were enrolled as the study participants. A trained operator collected the required information from the participants. The experiment was divided into 3 stages: pre-TENS acquisition, TENS application, and post-TENS acquisition. The pre-TENS stage was performed using surface electromyography (sEMG) (Myotronics Inc) to acquire the potential values of masticatory muscles in the following 3 states 5 times each: resting, intercuspal occlusion (ICO), and maximum voluntary clench (clenching). The potential values of the anterior of temporalis (TA), the masseter (MM), the sternocleidomastoid (SCM), and the anterior digastric (DA) muscles were collected in the resting state, and TA and MM were collected in the ICO and clenching states. During the TENS application phase, a TENS Unit device (J5 Myomonitor) (J5) was used on each participant for 45 minutes. The post-TENS acquisition phase involved the same procedure as the pre-TENS phase. The experimental data were recorded, and the normality of each group was analyzed using the Shapiro-Wilk test in a statistical software program (IBM SPSS Statistics, v26.0). The paired-sample t test was used to compare the differences in the mean values of sEMG and the asymmetry index (As); the independent-sample t test was used to compare the activity index (Ac) and torque index (To) (α=.05).
RESULTS
Significant differences were observed in the mean potential values of TA, MM, LSCM, and RDA before and after TENS in the resting state and RTA, LMM, and RMM before and after TENS in the clenching state (P<.05). Moreover, although As values showed a significant difference (P=.027) before and after TENS in the resting state, the differences in As values for the other muscles in the resting state were statistically similar. Furthermore, in each state, the mean values of Ac and To after TENS showed no significant differences before and after TENS (P>.05).
CONCLUSIONS
The resting EMG values of the TA and MM differed significantly before and after TENS. After TENS, the resting EMG activity decreased, whereas the functional EMG activity tended to increase.
PubMed: 38714456
DOI: 10.1016/j.prosdent.2024.03.022 -
Acta Odontologica Scandinavica Apr 2024Maxillofacial diseases may pose a risk factor for the onset of tinnitus, and may influence the severity of its symptoms. The objective of this study was to investigate...
INTRODUCTION
Maxillofacial diseases may pose a risk factor for the onset of tinnitus, and may influence the severity of its symptoms. The objective of this study was to investigate the prevalence of tinnitus among patients routinely visiting the Faculty of Dentistry and to assess the relationship between tinnitus and maxillofacial diseases.
MATERIALS AND METHODS
This was a prospective cross-sectional study conducted on 3,626 patients. Demographic data, information on tinnitus symptoms, temporomandibular disorder (TMD) presence, the existence of trigger points in masticatory muscles, toothache, and bruxism were evaluated.
RESULTS
Tinnitus was detected in 385 patients, resulting in a prevalence rate of 10.61%. Of the patients, 38.4% were male and 61.6% were female, and the mean age was 42.66 ± 16.34 years. Tinnitus was categorised as normal in 47.8% of the patients and pathological in 52.2% of the patients. Bruxism was identified in 65.5% of the patients, toothache in 42.9%, TMD in 33.8%, and masticatory trigger points in 27.0% of the patients. A tendency towards tinnitus provoked by toothache was observed in 5.9% of the patients. The presence of pathological tinnitus was found to increase the risk by 1.839 times for toothache and 1.456 times for bruxism.
CONCLUSION
There may be an association between oral and maxillofacial diseases and tinnitus, especially bruxism and toothache. Therefore, the evaluation of these conditions may be a routine part of tinnitus management.
Topics: Humans; Tinnitus; Female; Male; Adult; Cross-Sectional Studies; Prevalence; Middle Aged; Prospective Studies; Aged; Temporomandibular Joint Disorders; Adolescent; Risk Factors
PubMed: 38682700
DOI: 10.2340/aos.v83.40572 -
International Journal of Molecular... Apr 2024This review deals with the developmental origins of extraocular, jaw and laryngeal muscles, the expression, regulation and functional significance of sarcomeric myosin... (Review)
Review
This review deals with the developmental origins of extraocular, jaw and laryngeal muscles, the expression, regulation and functional significance of sarcomeric myosin heavy chains (MyHCs) that they express and changes in MyHC expression during phylogeny. Myogenic progenitors from the mesoderm in the prechordal plate and branchial arches specify craniofacial muscle allotypes with different repertoires for MyHC expression. To cope with very complex eye movements, extraocular muscles (EOMs) express 11 MyHCs, ranging from the superfast extraocular MyHC to the slowest, non-muscle MyHC IIB (nmMyH IIB). They have distinct global and orbital layers, singly- and multiply-innervated fibres, longitudinal MyHC variations, and palisade endings that mediate axon reflexes. Jaw-closing muscles express the high-force masticatory MyHC and cardiac or limb MyHCs depending on the appropriateness for the acquisition and mastication of food. Laryngeal muscles express extraocular and limb muscle MyHCs but shift toward expressing slower MyHCs in large animals. During postnatal development, MyHC expression of craniofacial muscles is subject to neural and hormonal modulation. The primary and secondary myotubes of developing EOMs are postulated to induce, via different retrogradely transported neurotrophins, the rich diversity of neural impulse patterns that regulate the specific MyHCs that they express. Thyroid hormone shifts MyHC 2A toward 2B in jaw muscles, laryngeal muscles and possibly extraocular muscles. This review highlights the fact that the pattern of myosin expression in mammalian craniofacial muscles is principally influenced by the complex interplay of cell lineages, neural impulse patterns, thyroid and other hormones, functional demands and body mass. In these respects, craniofacial muscles are similar to limb muscles, but they differ radically in the types of cell lineage and the nature of their functional demands.
Topics: Animals; Humans; Facial Muscles; Gene Expression Regulation, Developmental; Muscle Development; Myosin Heavy Chains; Oculomotor Muscles; Phylogeny
PubMed: 38674131
DOI: 10.3390/ijms25084546 -
Bioengineering (Basel, Switzerland) Mar 2024The purposes of this study are to establish and validate a finite element (FE) model using finite element analysis methods and to identify optimal loading conditions to...
The purposes of this study are to establish and validate a finite element (FE) model using finite element analysis methods and to identify optimal loading conditions to simulate masticatory movement. A three-dimensional FE model of the maxillary and mandibular cortical bone, cancellous bone, and gingiva was constructed based on edentulous cone-beam-computed tomography data. Dental computer-aided design software was used to design the denture base and artificial teeth to produce a complete denture. Mesh convergence was performed to derive the optimal mesh size, and validation was conducted through comparison with mechanical test results. The mandible was rotated step-by-step to induce movements similar to actual mastication. Results showed that there was less than a 6% difference between the mechanical test and the alveolar bone-complete denture. It opened 10° as set in the first stage, confirming that the mouth closed 7° in the second stage. Occlusal contact occurred between the upper and lower artificial teeth as the mouth closed the remaining angle of 3° in the third stage while activating the masseter muscle. These results indicate that the FE model and masticatory loading conditions developed in this study can be applied to analyze biomechanical effects according to the wearing of dentures with various design elements applied.
PubMed: 38671758
DOI: 10.3390/bioengineering11040336