Mandible protrusion and decrease of TMJ sounds: An electrovibratographic examination

This study quantified by, electrovibratography, the amount of mandible protrusion required to decrease significantly temporomandibular joint (TMJ) vibratory energy as an aid in the diagnosis of the recapture of anteriorly displaced disk. Eighteen patients diagnosed as having anterior disk displacement with reduction and TMJ clicking were submitted to electrovibratographic examination at the first appointment and treated with a stabilizing appliance and anterior positioning appliance with 1 to 5 mm protrusion. Vibratory energy was checked in each of these positions. Baseline data were used as control. At the first appointment, the patients had vibrations with more elevated intensities at the middle and late phases of the mouth opening cycle. At only one clinical step, mandible protrusion was obtained with the anterior repositioning appliance, ranging from 1 to 5 mm protusion. At each new position, a new electrovibratographic exam was made. After the 5-mm mandibular projection, only 2 patients presented vibration, with means between 0.6 and 2.8 Hz. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). The outcomes of this study indicate that 3 mm is the minimum amount of mandible protrusion to significantly decrease the TMJ vibratory energy and to recapture the displaced articular disk.

Effect of occlusion on joint sounds in asymptomatic individuals.

Occlusion is a predisposing factor for Temporomandibular Dysfunctions (TMD) of the joint, whose first sign and/or symptom is usually joint sound. To verify the effect of occlusion on joint sounds, temporomandibular joints (TMJ) were analyzed in 78 asymptomatic individuals with various dental conditions. Electrosonography was used to determine the intensity of the vibration in the temporomandibular joint (TMJ) on opening and closing the mouth. Transducers (piezoelectric accelerometer) were placed on the right and left joints. Results were tabled and analyzed using the Kruskal-Wallis test (a=0.05). It was concluded that TMJ vibration in partly edentulous individuals from Kennedy classes I, II and III is statistically higher than in dentate and fully edentulous subjects.

Associação entre otalgia, zumbido, vertigem e hipoacusia com desordens temporomandibulares

Because nonespecific symptoms and signs are associated with others well-established in the temporomandibular disorders, it is difficult for the clinician to decide what symptoms and signs should be considered during the diagnosis and the treatment plan. Therefore, the aim of this literature review was to evaluate the prevalence of aural symptoms (otalgias, tinnitus, dizziness and deafness) in patients with orofacial pain. Although several hypotheses have been proposed to explain the association between aural symptoms and temporomandibular disorders, the results of the previous studies differed in magnitude. For this reason, it is difficult to establish the prevalence of these aural symptoms concomitantly with temporomandibular disorders. Moreover, such relationship does not necessarily imply a cause-effect relationship. Because of the diagnosis complexity, different treatments must be considered, so the nonespecific symptoms of temporomandibular disorders can be effectively controlled as well. It is crucial for the the clinician to be aware of the possible etiology of aural symptoms, so he should determine if such symptoms may be associated with temporomandibular disorders and thus include them in the treatment.

Electromyographic evaluation of the temporal muscle after the use of interocclusal splints with a vibrating device in individuals with sleep bruxism

This is the first study performed with an interocclusal splint with a vibrating device on patients with sleep bruxism. The purpose of the present study was to evaluate the effectiveness of the splint with vibrating device on patients who suffer from sleep bruxism through computerized electromyography (EMG) of the anterior temporal muscles. Eight male and female patients, ranging in age from 18 to 28 years, with evident signs and symptoms of bruxism were selected. The splint were made for the upper arch. The patients was treated with the interocclusal splint with a vibrating device, and submitted to EMG evaluations of the anterior temporal muscles on both sides. The evaluations were performed at the beginning of treatment and after 21 days of splint use. Electromyography was performed in an isometric contractions measuring of the temporal muscles. The following results obtained revealed that: when closing the mandible (isometric contraction), the anterior temporal muscles had an expressive reduction in electromyographic activity (p. < 0.10), so this splints were considered effective for patients who suffer from sleep bruxism. © 2009 Springer-Verlag.

Joint sounds in complete denture wearers. Literature review.

Long-term denture wearers can present with prosthesis instability, reduced occlusal vertical dimension and incorrect positioning of the jaw. This can lead to muscular changes and joint vibration. This study presents the main considerations related to joint vibrations in partially or totally edentulous patients. Occlusal treatment improves the disc-condyle relationship in the mandibular fossa. Furthermore, a detailed clinical exam and anamnesis must be performed to identify the dysfunction and its etiology, so that appropriate treatment can be provided.

The effect of manual therapy on masseter muscle pain and spasm

Introduction: Orofacial pain and pain in the muscles of mastication are frequent symptoms of temporomandibular disorder. The masseter is the closet masticatory muscle to the surface and has the function of raising and retracting the mandible. This muscle has considerable strength and is one of the main muscles involved in the shredding of food It is therefore of utmost importance in the masticatory cycle and generally the most affected by pain and spasms. Objectives: The aim of the present study was to analyze the effect of manual therapy with transversal and circular movements on pain and spasm in the masseter muscle, using electromyography and a visual analogue pain scale (VAPS). Eight women who experienced pain upon palpation of the masseter greater than 6 on the VAPS were selected for participation in the study, which employed electromyography and a VAPS for assessment, followed by manual oral physiotherapy and reevaluation. Results: The statistical analysis revealed a reduction in pain, but there was no significant difference in electromyographic activity (p < 0.05). Conclusion: It was concluded that massage therapy was effective on pain symptoms, but was not capable of altering the electrical activity of the masseter muscle.

Relationship between psychological factors and symptoms of TMD in university undergraduate students.

Temporomandibular disorders is a collective term used to describe a number of related disorders involving the temporomandibular joints, masticatory muscles and occlusion with common symptoms such as pain, restricted movement, muscle tenderness and intermittent joint sounds. The multifactorial TMD etiology is related to emotional tension, occlusal interferences, tooth loss, postural deviation, masticatory muscular dysfunction, internal and external changes in TMJ structure and the various associations of these factors. The aim of this study was to evaluate the prevalence of the relationship between signs of psychological distress and temporomandibular disorder in university students. A total 150 volunteers participated in this study. They attended different courses in the field of human science at one public university and four private universities. TMD was assessed by the Research Diagnostic Criteria (RDC) questionnaire. Anxiety was measured by means of a self-evaluative questionnaire, Spielberger's Trait-State anxiety inventory, to evaluate students'state and trait anxiety. The results of the two questionnaires were compared to determine the relationship between anxiety levels and severity degrees of chronic TMD pain by means of the chi-square test. The significance level was set at 5%. The statistical analysis showed that the TMD degree has a positive association with state-anxiety (p = 0.008; p < 0.05) and negative with trait-anxiety (p = 0.619; p < 0.05). Moreover a high TMD rate was observed among the students (40%). This study concluded that there is a positive association between TMD and anxiety.

Effect of occlusal splint treatment on the temperature of different muscles in patients with TMD

Purpose: The aim of this study was to evaluate the effect of occlusal splint treatment on the temperature of masseter (inferior, intermediate and superior), anterior temporal, digastric and trapezius muscles in patients with temporomandibular disorder (TMD). Materials and methods: Thirty patients (6 male and 24 female) aged from 16 to 57 years (mean 37.8. ± 11.4 years) were selected. The patients were diagnosed with muscular TMD by clinical examination (application of Research Diagnostic Criteria questionnaire and physical examination). Occlusal splints in acrylic resin were inserted in all patients with a weekly follow-up. The superficial thermography (°C) on the both sides of the muscles was performed using a digital thermometer in a controlled temperature room. This procedure was performed before occlusal splint insertion (patient with pain) and after the completion of the treatment (patient without pain). The data were analyzed by 2-way repeated-measures ANOVA and means were compared by Tukey HSD test (P< .05). Results: After occlusal splint treatment a significant increase in temperature was observed in each muscle, both in the right and left sides. When the muscles were compared in the same period (before or after therapy) there was no significant difference among them. Conclusion: It can be concluded that the use of occlusal splint promoted a significant increase on the muscles temperature. There was symmetry in the temperature of muscles on the right and left sides both before and after the treatment. © 2010 Japan Prosthodontic Society.

Necrotizing sialometaplasia as a cause of a non-ulcerated nodule in the hard palate: A case report

Introduction. Necrotizing sialometaplasia is a benign, self-limiting and rare inflammatory disease which, on clinical and histological examination, mimics malignant neoplasms. Case report. We report the case of a healthy 25-year-old Caucasian woman with a three-week history of a painless lump on her hard palate. Oral examination revealed a nodule consisting of two lobules on the right side that measured 2.5 cm. Her mucosa was normal in color and a fluctuant area was detected in the posterior region upon palpation. Our patient was submitted to incisional biopsy and histopathological examination. The histological diagnosis was necrotizing sialometaplasia. The lesion had healed spontaneously after 30 days, with observed signs of involution of the nodule. Conclusion: Histopathological examination is necessary for the diagnosis of necrotizing sialometaplasia because the clinical features of this condition can mimic other diseases, particularly malignant neoplasms. © 2011 Oliveira Alves et al; licensee BioMed Central Ltd.

Sensibilidade dolorosa à palpação em pacientes con disfunção temporomandibularr crônica

The cephalalgias are frequently associated with the temporomandibular disorders being common to find an increase of pain sensitivity in these patients. Thus, the objective of present study was to assess the sensitivity to palpation in patients presenting with chronic temporomandibular disorders comparing two groups one with headache and other without it, respectively. The temporomandibular disorders and the primary cephalalgias were diagnosed according the Diagnostic Criteria for the Research of Temporomandibular Disorders and by a questionnaire based on the International Classification of the Cephalalgias (2004). Location, assessment and grouping of muscular and articular areas for palpation were carried out according to the Diagnostic Criteria for above mentioned disorders, considering bilaterally the masseter muscle, the temporalis muscle, the cervical region and the temporomandibular joint. Sample included 213 (88.0 %) of women and 29 (12.0 %) men with a mean age of 37.41 years. The mean of number of zones positive to palpation in the groups without headaches, tension headache, migraine and daily chronic headache were: 12.43, 14.38, 15.21 and 15.62 (p= 0.107) (min 2 max 22). The areas of temporalis muscle showed significant differences among groups (p= 0.007). The number of painful points was not statistically different among groups and only in the temporalis muscle there were differences with statistical significant to palpation.

Electromyographic analysis of masseter and anterior temporalis muscle in sleep bruxers after occlusal splint wearing

Bruxism is widely defined as an anxiety response to environmental stress. Occlusal splints are frequently used in sleep bruxism, to protect teeth from damage resulting from the contraction force of mandibular muscles, or to reduce the orofacial pain by relaxing masticatory muscles. Surface electromyography (EMG) of the right and left masseter and temporalis muscles was performed in 15 women presenting sleep bruxism and temporomandibular disorders related to occupational stress, after nocturnal use of the occlusal splint. The EMG signals were recorded twice per patient: After a work shift (pre-splint) and after a night of sleep with the occlusal splint (post-splint) before a new workday. The parametric t-paired test was used to compare differences of the RMS amplitude between pre and post-splint records, for resting and maximal clenching effort. The level of significance for each comparison was set to p < 0.05. The results of the study supports the premise that the use of occlusal splint reduces EMG activity in the masseter and anterior temporalis muscles, in patients who presented with sleep bruxism related to occupational stress. © 2011 Elsevier Ltd.

Evaluation of low-level laser therapy effectiveness on the pain and masticatory performance of patients with myofascial pain

This study investigated the effect of low-level laser therapy (LLLT) on the masticatory performance (MP), pressure pain threshold (PPT), and pain intensity in patients with myofascial pain. Twenty-one subjects, with myofascial pain according to Research Diagnostic Criteria/temporomandibular dysfunction, were divided into laser group (n = 12) and placebo group (n = 9) to receive laser therapy (active or placebo) two times per week for 4 weeks. The measured variables were: (1) MP by analysis of the geometric mean diameter (GMD) of the chewed particles using Optocal test material, (2) PPT by a pressure algometer, and (3) pain intensity by the visual analog scale (VAS). Measurements of MP and PPT were obtained at three time points: baseline, at the end of treatment with low-level laser and 30 days after (follow-up). VAS was measured at the same times as above and weekly throughout the laser therapy. The Friedman test was used at a significance level of 5 % for data analysis. The study was approved by the Ethics Committee of the Federal University of Sergipe (CAAE: 0025.0.107.000-10). A reduction in the GMD of crushed particles (p < 0.01) and an increase in PPT (p < 0.05) were seen only in the laser group when comparing the baseline and end-of-treatment values. Both groups showed a decrease in pain intensity at the end of treatment. LLLT promoted an improvement in MP and PPT of the masticatory muscles. © 2012 Springer-Verlag London.

Comparison of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible - A computed tomography-based three-dimensional finite element analysis

A finite element analysis was used to compare the effect of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible. Four models of an human mandible were constructed. In the OR (O'ring) group, the mandible was restored with an overdenture retained by four unsplinted implants with O'ring attachment; in the BC (bar-clip) -C and BC groups, the mandibles were restored with overdentures retained by four splinted implants with bar-clip anchor associated or not with two distally placed cantilevers, respectively; in the FD (fixed denture) group, the mandible was restored with a fixed full-arch four-implant-supported prosthesis. Models were supported by the masticatory muscles and temporomandibular joints. A 100-N oblique load was applied on the left first molar. Von Mises (σvM), maximum (σmax) and minimum (σmin) principal stresses (in MPa) analyses were obtained. BC-C group exhibited the highest stress values (σvM=398.8, σmax=580.5 and σmin=-455.2) while FD group showed the lowest one (σvM=128.9, σmax=185.9 and σmin=-172.1). Within overdenture groups, the use of unsplinted implants reduced the stress level in the implant/prosthetic components (59.4% for σvM, 66.2% for σmax and 57.7% for σmin versus BC-C group) and supporting tissues (maximum stress reduction of 72% and 79.5% for σmax, and 15.7% and 85.7% for σmin on the cortical and trabecular bones, respectively). Cortical bone exhibited greater stress concentration than the trabecular bone for all groups. The use of fixed implant dentures and removable dentures retained by unsplinted implants to rehabilitate edentulous mandible reduced the stresses in the periimplant bone tissue, mucosa and implant/prosthetic components. © 2013 Elsevier Ltd.

High condylectomy procedure: A valuable resource for surgical management of the mandibular condylar hyperplasia

Condylar hyperplasia is an overdevelopment of the condyle, which may manifest unilaterally or bilaterally. This pathological condition can lead to facial asymmetry, malocclusion, and dysfunction of the temporomandibular joint. The etiology and pathogenesis of condylar hyperplasia remain uncertain, but it has been suggested that its etiology may be associated with hormonal factors, trauma, and hereditary hypervascularity, affecting both genders. The diagnosis is made by clinical examination, and radiological imaging, and additionally, bone scintigraphy, is a fundamental resource for determining whether the affected condyle shows active growth. Patients with active condylar hyperplasia management have better results when they are subjected to the high condylectomy procedure. The authors report a case in a 20-year-old female subject with unilateral active condylar hyperplasia who was treated by high condylectomy. The patient has been followed up for 4 years without signs of recurrence and with good functional stability of the occlusion. © 2013 by Mutaz B. Habal, MD.

Arthrocentesis procedure: Using this therapeutic maneuver for TMJ closed lock management

Temporomandibular joint (TMJ) disorder is a term that encompasses a number of overlapping conditions, such as closed lock. Closed lock of the TMJ is considered a consequence of a nonreducing deformed disc acting as an obstacle to the sliding condylar head that usually causes a decrease in the maximum mouth opening and acute pain. The management of the TMJ is still controversial. Thus, arthrocentesis of the TMJ is a valuable modification of the traditional method of arthroscopic lavage, which consists of washing the joint in order to remove chemical inflammatory mediators and intra-articular adhesions, changing intra-articular pressure. TMJ disorder has always presented as a therapeutic challenge to maxillofacial surgeons. Therefore, this paper aimed to describe a clinical report of a closed lock of the left TMJ in a 19-year-old female subject who was successfully treated by arthrocentesis procedure. © 2013 by Mutaz B. Habal, MD.