Impact of clear aligner therapy on masticatory musculature and stomatognathic system: a systematic review conducted according to PRISMA guidelines and the Cochrane handbook for systematic reviews of interventions.

BACKGROUND: Clear aligner therapy has gained popularity as a minimally invasive orthodontic treatment option. However, its impact on the masticatory musculature and the stomatognathic system is an area of growing interest, as it involves the adjustment of occlusion and tooth movement. This systematic review aims to comprehensively assess and synthesise existing evidence regarding the influence of clear aligner therapy on the masticatory musculature and the stomatognathic system. METHODS: An exhaustive search was performed on electronic databases that adhered to PRISMA guidelines. Clinical studies that evaluated the impact of patients receiving aligner orthodontic treatment on the muscles of the mastication and stomatognathic systems were included. A standardised data extraction form was devised for relevant variables. Two reviewers extracted the data variables. ROB-2 was used for bias evaluation in the selected studies. RESULTS: A total of six studies met the inclusion criteria. The wearing of clear aligners significantly impacted the muscles of mastication. Muscle activity and discomfort showed a significant alteration in the initial days of appliance placement. but this observation was temporary, with no significant changes thereafter in subsequent follow-up. Bite force reduction was also noted. All the studies evaluated showed good methodological quality. CONCLUSION: The review found that aligned orthodontic treatment may have a variable impact on muscles of mastication, with a potential for initial exacerbation of symptoms followed by possible improvement. However, due to the limited number of studies and their heterogeneous nature, further robust research is recommended to fully understand the relationship between aligned orthodontic treatment and masticatory muscles.

Transfacial transmandibular approach to the masticator space: Excision of odontogenic myxoma arising from the mandibular condyle.

Odontogenic myxomas are an uncommon benign odontogenic tumor that can present with a wide variety of symptomatology depending on location and potentially be locally destructive. The present case describes a 66-year-old female who presented with left lower facial paresthesia, left aural fullness and hearing loss. She was found to have an odontogenic myxoma that involved the condylar head and extended into the masticator space. In this report we detail our surgical approach utilizing a preauricular transfacial transmandibular approach to the masticator space. In addition, we will discuss various approaches to the masticator space and infratemporal fossa along with considerations on how to manage facial nerve paralysis, facial contour deformities, and post-operative rehabilitation for permanent unilateral condylar head disarticulation.

Computed Tomography Findings of Emergency Cases Resulting From Fish Bone Ingestion.

Fish bones are some of the most commonly ingested foreign bodies. In most cases, fish bone ingestion is asymptomatic, and the bones are expelled from the body spontaneously. Otherwise, patients with fish bone ingestion can present to the emergency department with nonspecific symptoms. Fish bones can become impacted in various part of the body. Even in cases that are initially asymptomatic after ingestion, serious complications may develop at a later stage. Computed tomography (CT) plays an important role in the diagnosis of fish bone ingestion because it is the most sensitive modality for detecting these foreign bodies. It is important to be familiar with CT findings to detect ingested fish bones and the related complications and to direct further management of the condition.

Does Systemic Arterial Hypertension Change the Function of the Stomatognathic System?

The aim of this study was to evaluate the stomatognathic system of individuals with controlled systemic hypertension through comparison with a disease-free control group. Seventy individuals (44 female and 26 male) were divided into two groups: a controlled systemic hypertension (n=35) and a disease-free control (n=35). The individuals were evaluated on the basis of masticatory cycle efficiency of the value of the ensemble-averaged integrated linear envelope to the electromyographic signal of the masseter and temporalis muscles in the habitual (peanuts and raisins) and non-habitual chewing (Parafilm M); molar bite force (right and left) and ultrasound images from the bilateral masseter and temporal muscles at rest and maximum voluntary contraction. The data obtained were tabulated and submitted to statistical analysis (p<0.05). There was a significant difference between groups in the habitual (peanuts and raisins) and non-habitual (Parafilm M) chewing with reduced muscle activity to controlled systemic hypertension group. Muscle thickness occurred significant difference between groups at rest and maximum voluntary contraction of the temporalis muscles. There was no significant difference between groups in maximum molar bite force. The present study findings indicate that the controlled systemic hypertension promotes functional changes of the masticatory system, especially with respect to its masticatory efficiency and muscle thickness.

Correlation of Covid-19 With Stomatognathic System With Homeopathic Proposal for Adjunct Treatment to Increase Oral and General Health.

CONTEXT: SARS-CoV-2 is a new virus responsible for the outbreak of COVID-19. Studies have shown that the expression of ACE2 was found in the smaller salivary glands was higher than that in the lungs, suggesting that salivary glands may be a potential target of the virus. This may indicate that one of the main gateways to coronavirus infection is the oral cavity. OBJECTIVE: This review intended to evaluate the comorbidities of the oral cavity and their relationships to COVID-19 and to show the benefits of homeopathic therapies as adjuvant treatments to increase oral and general health and mitigate the devastating effects of the coronavirus. DESIGN: The authors conducted a narrative review of articles published in indexed journals and websites of dental institutions and the WHO. They were selected oral pathological manifestations, sleep disorders, mood, orofacial pain and bruxism, associated with the oral-facial manifestations of Covid-19 and articles of evidence of homeopathy in dentistry. SETTING: Study done in Brazil with research professors in Homeopathy and Periodontics in universities. RESULTS: Some studies report that patients who are more susceptible to anxiety and stress during the pandemic, due to social confinement, may have disorders in the stomatognathic system such as: neuralgic pain in the face and teeth, fractures of teeth and dental prostheses, nibbled mucosa, stomatitis, ulcers, pain in the Temporal Mandibular Joint, otalgias, dental tightening, bruxism, xerostomia, peeling of the mucous membranes and skin, facial paralysis. CONCLUSIONS: The researchers concluded that homeopathy is a safe and viable therapy for the control of COVID-19 symptoms, as scientific evidence has proven its benefits through clinical trials and use in previous epidemics. In dentistry, this therapy allows the dentist to act fully in the promotion of oral health and in the prevention of oral and systemic diseases.

Radiographic review of anatomy and pathology of the masticator space: what the emergency radiologist needs to know.

The differential diagnosis of a masticator space (MS) lesion is broad, owing in part to the multiple structures contained within such a small region. It is also because the MS is adjacent to many of the other deep spaces within the head and neck, which can act as gateways for disease spread. Therefore, emergency radiologists must be familiar with anatomy of the MS, as well as adjacent spaces in order to provide an accurate diagnosis to the referring clinician. This article illustrates the anatomy and common pathologies within the MS using a case-based multimodality approach. Common masticator space pathologies can be categorized into inflammatory/infectious, neoplastic, and vasoformative lesions. Important imaging features of MS lesions and patterns of disease spread will be discussed, with the aim of making this complex deep space more approachable in the emergent setting.

Effect of implant-supported mandibular overdentures versus reline on masticatory performance and salivary flow rates in very old adults-A randomized clinical trial.

PURPOSE: To compare the masticatory efficiency (ME), maximum voluntary bite force (MBF), masseter muscle thickness (MMT), and salivary flow rates (SFR) in completely edentulous dependent elders treated either with a conversion of their existing mandibular complete removable dental prostheses (CRDPs) into a two-implant overdenture (IOD) or a conventional reline of the CRDP. MATERIAL AND METHODS: Participants were randomly allocated into intervention (IG) and control (CG) groups. The IG received two implants in the mandibular canine regions, and their CRDPs were transformed into IODs. The CG received a conventional reline of their mandibular CRDPs. Outcomes were recorded at each recall visit (baseline, immediately, 3 months, 12 months after intervention, and subsequently on an annual basis). Statistical analyses used mixed linear regression models (level of significance: p < 0.05). RESULTS: The IG comprised 16 participants (age = 85.0 ± 6.2 years), while the CG comprised 16 (age = 84.8 ± 5.4 years), with a mean follow-up of 2.7 ± 2.2 years (range: 3 months-7 years). A significant increase of MBF in the IG was observed with an overall gain of 80 N (p < 0.001) compared with the reline group. There were no significant long-term changes in SFR, MMT, or ME within/between groups. CONCLUSION: Since dependent elders with mandibular IODs present a significant gain in MBF, but no relative increase in SFR, MMT, and ME, it seems that this increased capacity of MBF is not exploited by the elders during their habitual chewing.

Dental occlusion and body balance: A question of environmental constraints?

BACKGROUND: In the past few years, growing interest was given to the relationship between the dental occlusion and the body balance. While most research focused on this relationship at static conditions, it is evident that the contribution of the sensory information for balance control is different depending on the environmental constraints. RESEARCH QUESTION: The aim of the present paper was to elucidate whether the stomatognathic system (SS) contributes differently on body balance regulation according to the presence of external disturbances. METHODS: Literature regarding the different sources involved in the proprioceptive information to the SS was reviewed. The influence of dental occlusion on balance control at different external environments was then explored. RESULTS: The main findings are: (a) a plausible evidence between the masticatory and cervical muscles can be described; (b) a reciprocal connection between the trigeminal and vestibular nuclei supports the influence of the SS on body balance; (c) traditionally, research involving the relationship between the SS and balance control has focused on strictly controlled situations, thus, ignoring the sensory reweighting which occurs depending on the external disturbances; and (d) the afferences of dental occlusion for balance control seem strengthened when more difficult conditions are present. CONCLUSION: Results of the present review suggest that afferent signals from dental occlusion effectively contribute to balance control when more external perturbations are present, that is unstable support surface, fatigue and tasks being performed. However, more studies are needed to elucidate the mechanisms by which dental occlusion may influence balance control focusing on different external environments.

Satisfaction of patients with amyotrophic lateral sclerosis with an oral appliance for managing oral self-biting injuries and alterations in their masticatory system: A case-series study.

STATEMENT OF PROBLEM: About 10% of patients with amyotrophic lateral sclerosis (ALS) are candidates for oral treatment specifically because of traumatic injuries in the lips, cheeks, or tongue due to self-biting. However, patients with ALS have a prevalence of temporomandibular disorder (TMD) similar to that in the general population. PURPOSE: The purpose of this case-series study was to determine the degree of satisfaction of patients with ALS with an oral appliance for managing oral self-biting lesions or symptoms related to TMDs. This study also assessed the degree of improvement of the chief complaint and the compliance with and adverse effects of this treatment. MATERIAL AND METHODS: Eleven patients with ALS who sought oral treatment because of oral self-biting or TMD-related symptoms were included. A custom complete-coverage acrylic resin device was fabricated and fitted to each participant. A follow-up visit was planned for 3 months after the placement of the oral appliance, at which point the patients would rate the degree of improvement or worsening of the chief complaint and their degree of satisfaction with the treatment. A 1-sample t test was used to assess whether the degree of improvement of the chief complaint was significant. RESULTS: Participants reported a mean of 61% (95% confidence interval [CI] 38% to 84%) improvement of the chief complaint and a mean of 84% (95% CI 72% to 97%) satisfaction with the treatment. The mean rate of compliance was 62% (95% CI 40% to 84%) of the recommended time, and only a few adverse effects were reported. CONCLUSIONS: Participants with ALS were highly satisfied with the use of an oral appliance to manage oral self-biting or TMD-related symptoms. Adherence to this treatment was high, and no major adverse effects were observed.

Spinocerebellar ataxia: Functional analysis of the stomatognathic system.

BACKGROUND: Neurodegenerative diseases that affect the cerebellum, especially in elderly individuals, cause impairment of motor coordination and quality of life. The presente study evaluated the electromyographic activity and thickness of the right and left masseter and temporal muscles, and the maximum molar bite force of individuals with spinocerebellar ataxia. MATERIAL AND METHODS: Twenty-eight individuals were divided into two groups: those with (n=14) and without (n=14) spinocerebellar ataxia. Data on the masticatory muscles obtained from the electromyographic activity (resting, right and left laterality and protrusion), muscle thickness (maximal voluntary contraction and tensile strength) and maximum bite force (right and left) were tabulated and descriptive analysis using Student's t-test (P ≤ 0.05). RESULTS: In the comparison between groups, greater electromyographic activity was demonstrated for individuals with spinocerebellar ataxia, with a statistically significant difference in protrusion and laterality for the temporal muscles (P = 0.05). There was no statistically significant difference between the groups for masticatory muscles thickness in the conditions evaluated. For maximum molar bite force, the group with spinocerebellar ataxia showed lower bite force (P ≤ 0.05). CONCLUSIONS: The data obtained suggest that spinocerebellar ataxia promotes functional reduction in the stomatognathic system, mainly affecting the electromyographic activity and bite force, hindering chewing, with a resultant alteration of nutritional intake and a decrease of quality of life.

Assessment of the Temporomandibular Joint Function in Young Adults without Complaints from the Masticatory System.

Objective of the study was to evaluate the clinical status of the masticatory system in young adults with full permanent dentition and no stomatognathic system complaints. The study involved 186 randomly selected people with full dental arches with normal occlusal conditions corresponding to Angle's Class I aged 18 - 21 years with an average age of 19 years. Subjects were clinically examined and temporomandibular joint (TMJ) vibrations were recorded during open-wide and close movements using BioJVA. Then, patients were categorized into groups according to Piper's classification system. The TMJs of the subjects were categorized according to the values of the vibration energy and the Piper protocol. This detected 33.4% of the joints with loosened ligaments, subluxation in 8.28%, initial signs of disc dysfunction in 5.08% and disc displacement without locking in 1.6 %. Median frequency differed significantly (p < 0.05) between the group of subjects with initial signs of TMJ dysfunction and other groups. Peak Frequency differed significantly (p < 0.05) between the healthy joints and those with TMJ subluxation. In this group of young healthy people, the majority of study joints generated small vibrations. However, a subset of people manifested higher vibrations that may indicate an early stage of TMJ dysfunction. Median Frequency was an important parameter for detecting initial symptoms of TMJ dysfunction. Peak Frequency was an important characteristic parameter for detecting TMJ subluxation.

Adaptation to new complete dentures-is the neuromuscular system outcome-oriented or effort-oriented?

OBJECTIVE: The aim of this study was to observe the adaptation strategy of the stomatognathic system during the adaptation of complete dentures, comprising masticatory parameters and subjective measures. Our hypothesis was that with new dentures, masticatory performance would increase while the effort of the system is kept constant. MATERIAL AND METHODS: Thirty-two patients received standardized new complete dentures. Masticatory performance tests were conducted with old dentures (T1), immediately after incorporation of new dentures (T2) and after an adaptation period of 3 months (T3). Patients habitually chewed the silicone-based artificial test food Optocal. The comminuted test food was analyzed and mean particle sizes (x50) were calculated. Simultaneously, surface EMGs of the anterior temporalis and masseter muscles were recorded. Specific (SMW) and total muscle work (TMW) were determined. Patients filled in the OHIP-49 questionnaire. Test conditions were compared using repeated-measures ANOVA with SPSS 22 (SPSS Inc.) RESULTS: Masticatory performance increased (P = 0.016) between old (x50 = 4.99 ± 0.28) and adapted new dentures (x50 = 4.80 ± 0.33). TMW deteriorated (P = 0.004) at T2 (from TMW1 = 119.77 ± 56.49 to TMW2 = 92.12 46.27), and increased again (P = 0.028) at T3 (TMW3 = 107.66 ± 44.65). OHIP scores decreased significantly in all subscales (P < 0.001…P = 0.046); the total score was reduced (P < 0.001) from 56.24 ± 29.05 (T1) to 34.66 ± 24.74 (T3). CONCLUSION: In complete denture wearers, masticatory performance improves over an adaptation period. Muscle work initially decreased before reaching its original level again after adaptation. Subjective parameters overestimated the functional improvements. CLINICAL SIGNIFICANCE: The subjective evaluation does not adequately reflect functional improvements. The assessment of function requires an adaptation period.

Functional limitation of the masticatory system in patients with bulbar involvement in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) with bulbar dysfunction affects the motor neurons responsible for controlling the muscles in the jaw, face, soft palate, pharynx, larynx and tongue. This cross-sectional study aimed to determine the functional limitation of the jaw in patients with ALS and bulbar dysfunction who had upper motor neuron (UMN), lower motor neuron (LMN) or balanced involvement. One hundred and fifty-three patients with ALS and 23 controls were included. All participants answered using the 8-item Jaw Functional Limitation Scale (JFLS-8). Patients with ALS were grouped by neurologic examination as follows: non-bulbar ALS, bulbar UMN-predominant ALS; bulbar LMN-predominant ALS; and bulbar balanced (UMN + LMN) ALS. Jaw limitation between the different groups was compared using the Kruskal-Wallis test. Patients with non-bulbar ALS had similar mandibular limitations to healthy participants. Only patients with balanced UMN and LMN bulbar manifestations reported greater difficulties in chewing soft food or in jaw mobility compared to the non-bulbar ALS group. Patients with bulbar involvement also had greater difficulties in chewing tough food or chicken and in swallowing and talking compared to the non-bulbar group, regardless of whether UMN or LMN predominant. No significant differences were found between the groups in smiling and yawning difficulties. Bulbar involvement in patients with ALS is associated with functional limitation of the masticatory system. However, balanced bulbar UMN and LMN involvement is associated with the worst impairments in chewing soft food and in opening the jaw widely.

Influence of removable prostheses on mastication in elderly subjects with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a prevalent disease in the elderly population, and it may affect the temporomandibular joint (TMJ) and the stomatognathic system. This study evaluated masticatory function in elderly patients with RA before and after oral rehabilitation with removable prostheses. Forty-five elders with partial or total edentulism who were using unsatisfactory removable prostheses were selected and assigned to 3 groups: RA with TMJ involvement, RA without TMJ involvement and healthy controls. Masticatory function was assessed in terms of masticatory performance (MP) and maximum bite force (MBF). The former was determined by the sieving method, and the latter was measured by pressure sensors placed in the bilateral molar regions. The variables were first evaluated in elderly subjects wearing unsatisfactory prostheses and re-assessed after participants had received new removable prostheses. Comparisons between groups and among time points were performed with analysis of variance for repeated measures and the Tukey-Kramer test (P < .05). Comparison among groups showed decreased MP in elders with RA before new prosthesis insertion (P < .05). Irrespective of TMJ involvement, MP improved after treatment in subjects with RA. Rheumatoid arthritis groups also showed decreased MBF (P < .05), which improved after new prosthesis insertion. Rheumatoid arthritis might impair masticatory function, and well-fitted removable prosthesis insertion might be very beneficial in elders with RA.

Human jaw joint hypermobility: Diagnosis and biomechanical modelling.

Patients with hypermobility disorders of the jaw joint experience joint sounds and jerky movements of the jaw. In severe cases, a subluxation or luxation can occur. Clinically, hypermobility disorders should be differentiated from disc displacements. With biomechanical modelling, we previously identified the anterior slope angle of the eminence and the orientation of the jaw closers to potentially contribute to hypermobility disorders. Using cone-beam computed tomography (CBCT), we constructed patient-specific models of the masticatory system to incorporate these aspects. It is not known whether the clinical diagnosis of hypermobility disorders is associated with the prediction of hypermobility by a patient-specific biomechanical model. Fifteen patients and eleven controls, matched for gender and age, were enrolled in the study. Clinical diagnosis was performed according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and additional testing to differentiate hypermobility from disc displacements. Forward simulations with patient-specific biomechanical models were performed for maximum opening and subsequent closing of the jaw. This predicted a hypermobility disorder (luxation) or a control (normal closing). We found no association between the clinical diagnosis and predictions of hypermobility disorders. The biomechanical models overestimated the number of patients, yielding a low specificity. The role of the collagenous structures remains unclear; therefore, the articular disc and the ligaments should be modelled in greater detail. This also holds for the fanned shape of the temporalis muscle. However, for the osseous structures, we determined post hoc that the anterior slope angle of the articular eminence is steeper in patients than in controls.

Symptoms in the masticatory system and related quality of life in prospective orthognathic patients.

OBJECTIVE: The aim of this study was to investigate the relation between orthognathic patients' self-reported symptoms in the head and neck region and their quality of life (QoL). MATERIAL AND METHODS: Participants included were consecutive patients (n = 50) referred to the assessment of orthognathic treatment need and voluntary first-year university students (n = 29). All participants filled in the Orthognathic Quality of Life Questionnaire (OQLQ) and a structured diary created by the authors. The median values of Orthognathic Quality of Life (OQOL) sum and subscores, satisfaction with oral function and number of awakenings were compared between patients and controls. Further, correlations between the OQOL sum and subscores, satisfaction with oral function and number of awakenings were analyzed. RESULTS: Patients reported significantly more symptoms (p = .013) and woke up significantly more often than the controls (p = .032). Their OQOL sum scores were significantly higher (indicating a lower OQOL) (p = .001), and they were significantly less satisfied with their oral function than the controls (p < .001). Among the awakened and not-rested patients, the most commonly reported symptoms were pain in the head and/or neck region and fatigue and/or stiffness in the jaws. CONCLUSIONS: Experiences of pain and discomfort have a significant impact on patients' OQOL and well-being.

Computer-assisted technologies used in oral rehabilitation and the clinical documentation of alleged advantages - a systematic review.

The objective of this systematic review is to identify current computer-assisted technologies used for managing patients with a need to re-establish craniofacial appearance, subjective discomfort and stomatognathic function, and the extent of their clinical documentation. Electronic search strategies were used for locating clinical studies in MEDLINE through PubMed and in the Cochrane library, and in the grey literature through searches on Google Scholar. The searches for commercial digital products for use in oral rehabilitation resulted in identifying 225 products per November 2016, used for patient diagnostics, communication and therapy purposes, and for other computer-assisted applications in context with oral rehabilitation. About one-third of these products were described in about 350 papers reporting from clinical human studies. The great majority of digital products for use in oral rehabilitation has no clinical documentation at all, while the products from a distinct minority of manufacturers have frequently appeared in more or less scientific reports. Moore's law apply also to digital dentistry, which predicts that the capacity of microprocessors will continue to become faster and with lower cost per performance unit, and innovative software programs will harness these improvements in performance. The net effect is the noticeable short product life cycle of digital products developed for use in oral rehabilitation and often lack of supportive clinical documentation. Nonetheless, clinicians must request clinically meaningful information about new digital products to assess net benefits for the patients or the dental professionals and not accept only technological verbiage as a basis for product purchases.

Impact of temporomandibular disorders on the stomatognathic system in children.

BACKGROUND: To evaluate the EMG activity and thickness of right masseter (RM), left masseter (LM), right temporal (RT) and left temporal (LT) muscles and bite force in children with temporomandibular disorders (TMD). MATERIAL AND METHODS: Forty five children (mean age 8.8 years; 22 boys and 23 girls) were examined on the basis of the RDC/TMD and the Faces Pain Scale-Revised (FPS-R) was used to determine the level of severity of the signs and symptoms of TMD, resulting in four groups: GI - without TMD (n=10); GII - with mild TMD (n=18), GIII: with moderate TMD (n=12) and GIV: with severe TMD (n=5). The data of electromyographic activity, maximum bite force and muscle thickness were tabulated and submitted to statistical analysis (ANOVA, P≤0.05). RESULTS: Children with TMD signs and symptoms had lower EMG activity than children of the control group. There was significant difference among the groups for the LT at rest (P=0.01), right (P=0.03) and left (P=0.05) laterality, and for the LM (P=0.01) and LT (P=0.03) muscles in maximum voluntary contraction. There were no statistically significant differences among the groups regarding muscle thickness. The bite force was lower in the TMD groups than children of the control group, with significant statistical difference for the right region (P=0.03). CONCLUSIONS: The severity of TMD signs and symptoms affected the EMG activity and the molar bite force in children. However, structural changes in the thickness of masticatory muscles are not perceptible in children with TMD signs and symptoms.

Stomatognathic function in Duchenne muscular dystrophy: a case-control study.

AIM: This study aimed to analyse electromyographic activity, masticatory efficiency, muscle thickness, and bite force of individuals with Duchenne muscular dystrophy (DMD). METHOD: Forty males aged 4-15 years, 20 with DMD and 20 healthy age-, height-, and weight-matched controls, underwent electromyography and ultrasonography of temporalis, masseter, and sternocleidomastoid muscles during postural control of the jaw, mastication, and maximal molar bite force. RESULTS: The normalized electromyography signals showed higher activity in masseter and temporal muscles at rest, during protrusion, left and right laterality, and fatigue condition in the group with DMD than in the comparison group (p≤0.05). For masticatory efficiency of cycles, in analysis of non-habitual chewing of flavourless gum, and habitual chewing of peanuts and raisins, the group with DMD presented lower averages (p≤0.05). For the muscle thickness, the results showed that there was a lower muscle thickness in the group with DMD for all muscles during the rest and maximal voluntary contraction, except for masseter and sternocleidomastoid in the maximal voluntary contraction. In the maximal molar bite force, the group with DMD presented higher values for both sides than the comparison group (p≤0.05). INTERPRETATION: Patients with DMD show muscle changes related to the stomatognathic system, in their activity, bite force, and muscle thickness.

Influence of wearing a scuba diving mouthpiece on the stomatognathic system - considerations for mouthpiece design.

Although diver's mouth syndrome (DMS) has long been recognized by scuba divers, little attention has been paid to the influence of wearing a scuba diving mouthpiece on the stomatognathic system. In this review, DMS-related stomatognathic events (DMS-SE) while wearing a mouthpiece, the relationship between components of the mouthpiece and those events, and design considerations to reduce the risk of those events are discussed based on evidence from 32 articles concerning scuba diving mouthpieces. Forward movement of the mandible, loss of molar occlusal support, and continuous jaw clenching while wearing a mouthpiece are considered to be pathogenic for DMS-SE. Several experimental studies have suggested a relationship between incidence of those events and the design of mouthpiece components such as the connector, labial flange, platform, and occlusal rug, and the possibility of reducing risk of those events through design customization of these components. Improvement of the shape of commercially available mouthpieces and creation of custom-made mouthpieces may thus contribute to the prevention and treatment of DMS-SE and the provision of a comfortable diving environment.