Signs Of Temporomandibular Disorders Research Articles

Congenitally missing maxillary lateral incisors: long-term periodontal and functional evaluation after orthodontic space closure with first premolar intrusion and canine extrusion

The aims of this investigation were to evaluate associations between orthodontic space closure (including first premolar intrusion and canine extrusion for esthetic reasons) and periodontal tissue deterioration over a 10-year period in subjects with one or both missing maxillary lateral incisors and to investigate the occurrence of signs or symptoms of temporomandibular disorder (TMD). This was a retrospective cohort study comprising patients treated by the same orthodontist. The agenesis group included 26 consecutive adolescent and young adult patients (9 male, 17 female) treated with space closure. The control group consisted of 32 orthodontic patients (12 male, 20 female) with no missing teeth and no need for extractions. In the agenesis group, full-mouth probing pocket depths and bleeding on probing were recorded at six locations for each of 657 teeth (3942 periodontal sites). In the control group, comparative data were collected for the maxillary first molars, premolars, canines, and lateral incisors, a total of 264 teeth (1584 periodontal sites). Mobility and gingival recession were also evaluated. Patients in both groups completed questionnaires concerning symptoms related to TMD. The full-mouth assessments in the agenesis group generally demonstrated periodontally healthy conditions, with probing depths below 4 mm and few bleeding sites. Some slight recessions were found, mostly on molars and second premolars, and there was normal mobility of first premolars that substituted for canines. Comparisons between the agenesis and control groups showed no statistically significant differences for the maxillary teeth regarding increased pocket depth (≥ 4 mm) or increased mobility. Interproximal sites in the agenesis group showed less bleeding on probing than in the control group; this was statistically significant. Anterior teeth in the agenesis group did not show any more recession than in the controls. In addition, we observed no difference in signs or symptoms between the two groups; this might be due to the limited sample size or the drawbacks of the surveys of TMD through subjects' recall. Thus, the long-term periodontal tissue health and the incidence of dysfunction or TMD signs were similar in the space-closure agenesis group and in the control group of nonextraction orthodontic patients. Orthodontic space closure including first premolar intrusion and canine extrusion in patients with missing lateral incisors does not incur risks for periodontal tissue deterioration or TMD in the long term.

Temporomandibular Disorder Signs, Occlusal Support, and Craniofacial Structure Changes Among the Elderly Vietnamese.

The aim of study was to determine the association between signs of temporomandibular disorders (TMD), occlusal support, and alterations in the craniofacial structure of elderly Vietnamese by using cephalometric analysis. The cross-sectional study consisted of 244 participants aged 65-74years. Participants were examined for signs of TMD, including limited mouth opening, temporomandibular joint (TMJ) crepitus, TMJtenderness, and muscle tenderness. Dentition was divided into four occlusal support zones based on occluding pairs of posterior teeth by using Eichner's classification: Class A=4 support zones; Class B=1-3 support zones or only contact inanterior teeth; Class C=0 support zones. Fifteen angular and seven linear parameters were used for sagittal craniofacial skeleton analysis. 10.3% of participants had limited mouth opening, 49.6% TMJ crepitus, 16.3% TMJ tenderness, and 24.2% muscle tenderness; 45.5% had Class A occlusal support, 38.5% Class B, and 16.0% Class C. Those with Class C had significantly smaller ramus inclination, articular angle, and angles formed by the mandibular plane and shorter facial height compared to Class A and Class B (P<.001). TMD signs were significantly associated with: angles formedby mandibular plane, gonial angle, cranial base angle, effective mandibular length, and anterior facial height (P<.05). The alteration of craniofacial structures was significantly associated with TMD signs among elderly Vietnamese. The higher number of lost occlusal support zones, the more significant the changes to craniofacial structures.

Deviation of the mandibular labial frenum as related to signs and symptoms of temporomandibular disorders (TMDs)

Aim: To investigate the association between mid-line deviation of the mandible, as determined by upper to lower labial frena, and signs and symptoms of Temporomandibular Disorders (TMDs). Materials and Methods: The current study was original research conducted on a sample of 439 medical records of TMD patients treated at Tufts University. All patients underwent a clinical examination revealed a detailed information regarding temporomandibular joints, history of pain, and comprehensive intra-oral findings. Subjects were divided into three groups: 1. No frenal deviation, 2. Deviation to the right, and 3. Deviation to the left. Results: Signs and symptoms of TMD tend to occur more likely on the side of the frenum deviation. The signs and symptoms that were significantly associated to frenum position were TMJ crepitation sounds and locking, right muscles pain on palpation (medial pterygoid and sternocleidomastoid), and “reported locking on the left TMJ”. Subjects with aligned frena showed a statistically significant increase in the range of motion to the right side. The results also revealed a highly significant association between maxillary plane canting and mandibular frenum position. Left posterior cross bite was significantly more prevalent in the left frenum deviation group. Conclusion: Expression of TMD signs and symptoms was more prevalent on the side of frenum deviation. TMD population showed a higher prevalence of left mandibular frenum deviation. Several signs and symptoms were significantly associated to frenum position.

Temporomandibular clinical exploration in Italian adolescents

Objective: This study investigated the prevalence of the signs and symptoms of temporomandibular disorders (TMD) among Italian adolescents.Methods: The data were recorded from 567 subjects (246 males and 321 females; age range 11–19 years), grouped according to age and molar class relationship.Results: Forty-four point one percent of subjects showed at least one sign or symptom of TMD, which were significantly more frequent in the 16–19 year-old group (52.9%) in respect to the 11–15 year-old group (39.8%) (χ2 = 8.78; p = 0.003). Signs and/or symptoms were about 1.6 times more frequent in subjects with Class II/1 malocclusion (χ2 = 13.3, p = 0.0003), mostly for TMJ sounds (χ2 = 1.444; p = 0.036). Myalgia was more frequent in females than in males (χ2 = 3.882; p = 0.049).Conclusion: TMD signs and/or symptoms among Italian adolescents seem diffused (44.1%). Therefore, all adolescents should be screened thorough medical history and clinical examination.

Influence of anthropometry, TMD, and sex on molar bite force in adolescents with and without orthodontic needs.

Bite forcehas been studied as representative of functional indices of mastication and its value may have diagnostic significance in disorders of the musculoskeletal system of facial bones. This study aimed to evaluate bite force in adolescents with and without orthodontic needs considering presence of temporomandibular disorders (TMD) as well as anthropometry: craniofacial dimensions and body mass index (BMI). A total of 80 subjects were screened (61 females, 19 males; 18±3years old). Unilateral molar bite force was measured using a digital dynamometer with a fork thickness of 12mm. Direct anthropometry was used to quantify craniofacial measurements. Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) and the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were used to classify samples according to malocclusion and to TMD, respectively. Data were analyzed using normality tests, Mann-Whitney U test, and multiple linear regression analyses with stepwise backward elimination, controlling for the presence of malocclusion and TMD (p≤0.05). The cephalic index was greater in females with malocclusion and the longitudinal cranial diameter was reduced in females with malocclusion. BMI was not different between normal and malocclusion groups for either gender. Bite force was negatively related with vertical dimension of the face, and positively related with facial width and facial index. The model explained 32% of bite force variability, considering the sample size (coefficient of determination R 2=0.324). Even when orthodontic needs and TMD signs and symptoms are present, stronger bite force is still observed in males and in subjects with smaller anterior facial heights and wider facial widths.

Dental and skeletal maturation in female adolescents with temporomandibular joint osteoarthritis

Occurrence of temporomandibular disorders (TMDs) and temporomandibular joint (TMJ) osteoarthritis (OA) during adolescence may have interactions with mandibular and dental development. The aim of the present study was to investigate relationships between occurrence of TMD and TMJ OA and extents of dental and skeletal development in juvenile female patients. In total, 95 female adolescents (age range, 11-15years) were selected. Among them, 15 subjects (control) had no signs of TMD, 39 TMD patients did not have OA (TMDnoOA), 17 TMD patients were at initial stage of TMJ OA (TMJOA), and 27 patients showed progressive stage of TMJ OA (TMJOA). Dental age was estimated by Demirjian's stages used in a previous study with Korean adolescents. Craniofacial parameters and cervical vertebrae maturation (CVM) stages, representing skeletal maturity levels, were measured using lateral cephalograms. The estimated dental age was significantly lower than chronological age in all groups, but CVM differences were not statistically significant. Dental age was the lowest, and differences between the chronological age and estimated dental age were the highest among initial stage of TMJOAs followed by progressive stage of TMJOAs, TMDnoOAs and control and were not associated with CVM stages. Cephalometric parameters revealed significant clockwise rotation of the mandible among the TMJOAs compared with controls and TMDnoOAs and were not associated with CVM stages as well. The juvenile female patients with TMD, particularly TMJ OA, showed retarded dental development, mandibular backward positioning and hyperdivergent facial profiles. The TMJ OA may be associated with retarded dental development but not with skeletal maturations.

Determinants for craniofacial pains in children 6–8 years of age: the PANIC study

Objective: Determinants for orofacial pain, headache, morning headache and painful signs of temporomandibular disorders (TMD) were investigated in prepubertal children.Material and methods: The participants were a population sample of 439 children aged 6–8 years. Craniofacial pains, eating meals and snacks, sleep bruxism, sleep quality, sleep-disordered breathing (SDB), psychological well-being, parental education and household income were assessed by questionnaires filled out by the parents. Sleep duration was assessed using a combined heart rate and movement sensor and clinical signs of TMD and dental occlusion by a dentist. The determinants of pain conditions were analyzed using logistic regression.Results: Of all 439 children, 26% had experienced orofacial pain and 31% headache during the past 3 months, 17% had suffered morning headache weekly and 13% had painful signs of TMD in a clinical examination. Restless sleep was associated with increased risk of orofacial pain, the painful signs of TMD and restless sleep with increased risk of headache and restless sleep, sleep bruxism and skipping meals with increased risk of morning headache after adjustment for other independent determinants of these pain conditions. Headache was associated with increased risk for painful signs of TMD.Conclusions: Craniofacial pains are common among prepubertal children. Prepubertal children with sleep bruxism, restless sleep and skipping meals have increased likelihood of craniofacial pains.

Kapanışı olmayan dişlerde uzama, dönme, devrilme sıklığı ve temporomandibular düzensizlikler ile ilgili çalışma

Aim: The purpose of this study was to determine the incidence of overeruption, rotation and tipping in unopposed posterior teeth and study the association among temporomandibular disorders (TMD). Material and Methods: The study group consisted of 191 patients with posterior tooth loss. These teeth (462 molars) overeruption, rotation and tipping records were reviewed. Tooth loss and TMD symptoms were detected. In order to compare the variables Chi-square tests and Fisher’s exact probability test were used. For TMD, Pearson correlation prevalence parameters were used. Results: 291 molars showed no signs of overeruption. 119 molars showed slight, 52 molars had erupted moderate to severe eruption. 184 molars had no signs of rotation, 203 were rotated less than 15°, while 75 molars were rotated more than 15°. 274 molars showed no signs of tipping whereas, 108 had tipping less than 15°, and 80 molars had tipping of greater than 15°. Younger age group and female gender were found to be statistically significant regarding mean scores of TMDs (Age: p<0.05, Gender: p<0.001) Conclusions: Molar rotation was more frequent in the maxilla; whereas overeruption and tipping were more common in the mandible Significant associations between the signs of TMD and tooth loss were found, but the current results does not support the concept that loss of molar support is an etiologic factor in TMDs.

Use of botulinum toxin type a in temporomandibular disorder

ABSTRACT Temporomandibular disorder (TMD) may be defined as a set of clinical scenarios involving the masticatory muscles, the temporomandibular joint (TMJ) and associated structures. Currently, 40 to 75% of the population has some sign of temporomandibular disorder, mainly pain located in the muscles of mastication in the pre-auricular region. The present clinical case was diagnosed as muscle temporomandibular disorder secondary to parafunction, as well as muscle hyperactivity due to surgical displacement of the left temporal muscle on two occasions, one for placement of aneurysm clips and the other for tumor excision from the supraorbital region on the left side. The patient sought medical and dental attention for 10 years due to constant headaches, tiredness and pain in the cheeks. The patient tried numerous bite-guards and pharmacological therapies to no avail. The American Academy of Orofacial Pain Questionnaire was applied combined with the Criteria for Research and Diagnostics (DRC) and a decision was made to use botulinum toxin type A in the masseter and temporalis muscles. An analog pain scale was applied over 90 days. Three days following the application of botulinum toxin type A, the patient reported a significant improvement with complete resolution of pain (level 0) after 90 days. At 12 weeks from starting treatment, facial muscle physiotherapy was introduced to strengthen the muscles of mastication and the patient remained pain-free, which allowed the preparation and adaptation of a snap-on prosthetic appliance. In conclusion, the use of botulinum toxin in patients with temporomandibular disorder should be considered as a viable therapeutic option.

Psychopathologic Profiles of TMD Patients with Different Pain Locations

The aim of this study was to examine whether psychopathologic profile is related to the location of pain in temporomandibular disorder (TMD) patients with myofascial and/or temporomandibular joint pain. A total of 75 painful TMD patients (39 women and 36 men) participated in the study. Participants were divided into three groups (myogenous, arthrogenous, and mixed) using the Research Diagnostic Criteria for TMD (RDC/TMD) Axis I guidelines for assessment of TMD signs and symptoms. Three psychometric instruments were used to assess the psychopathologic profile of the TMD subgroups. Patients' state and trait anxiety were assessed using the State-Trait Anxiety Inventory (STAI-S, STAI-T), depression was measured with the Center for Epidemiological Studies Depression Scale (CES-D), and psychosocial functioning was evaluated using the Global Disability Scale (Glo.Di.S). The three TMD groups were compared with Kruskal-Wallis test followed by pairwise Mann-Whitney tests relative to the psychometric scores. Statistical analyses were performed with SPSS 15.0 software. No significant differences were detected among the different TMD groups in the three psychometric scales; STAI-T, CES-D, Glo.Di.S (P > .05). When the psychometric scale of state anxiety (STAI-S) was considered, significant differences were revealed between the myogenous and the arthrogenous pain groups (P = .008) and also between the mixed and the arthrogenous groups (P < .001). These findings suggest that the psychopathologic profile is not related to the location of pain in TMD patients. However, anxiety was found to be higher in TMD patients with myogenous pain alone or combined with arthrogenous pain compared to those with only arthrogenous pain.

Association Between Severity of Temporomandibular Disorders and the Frequency of Headache Attacks in Women With Migraine: A Cross-Sectional Study

ObjectiveThe aim of this study was to investigate the magnitude of association of the severity of temporomandibular disorders (TMDs) in women with episodic and chronic migraine. MethodsThirty-one women with episodic migraine (mean age: 33 years), 21 with chronic migraine (mean age: 35 years) and 32 healthy controls (mean age: 31 years) were included. The Fonseca Anamnestic Index was applied to assess severity of TMDs. TMD severity was considered as follows: no TMD (0-19 points), mild TMD (20-49 points), moderate TMD (50-69 points), and severe TMD (70-100 points). To compare the proportion of TMD severity among groups, a χ2 test was performed. Prevalence ratio (PR) was calculated to determine the association of TMD severity and both migraine groups using the control group as the reference. ResultsWomen with chronic and episodic migraine were more likely to exhibit TMD signs and symptoms of any severity than healthy controls (χ2 = 30.26; P < .001). TMD prevalence was 54% for healthy controls, 78% for episodic migraine, and 100% for chronic migraine. Women with chronic migraine exhibited greater risk of more severe manifestations of TMD than healthy controls (PR: 3.31; P = .008). This association was not identified for episodic migraine (PR: 2.18; P = .101). ConclusionThe presence of TMD signs and symptoms was associated with migraine independently of the frequency; however, the magnitude of the association of more severe TMD was significantly greater in chronic, but not episodic, migraine.

Symptoms and signs of temporomandibular disorders in patients with knee osteoarthritis

Both temporomandibular disorder (TMD) and knee osteoarthritis (KOA) are prevalent joint diseases; however, an association between them has not been reported. Therefore, this study investigated the prevalence of the specific symptoms and signs of TMDs (SSTs) in patients with KOA. In total, 200 patients with KOA and 150 healthy individuals were recruited. The prevalence of specific SSTs in patients with mild or severe KOA was compared with the prevalence of specific SSTs in the control group and the results were analysed using a chi-square test. Logistic regression was used to adjust for potential confounders, such as gender and age. The prevalence of 'impaired range of jaw movement (IRM)' was 63.6% (n = 77) in the mild KOA group and 62.4% (n = 117) in the severe KOA group; the values for both KOA groups were significantly higher than that for the non-OA control group (34.7%, n = 144; P < 0.017). In addition, 54.7% of the patients with severe KOA reported 'impaired temporomandibular joint (TMJ) function', a value significantly higher than that of the control group (39.6%, P < 0.017). No significant differences between groups were found for other SSTs. Patients with KOA might be more likely to experience SSTs, such as IRM and impaired TMJ function.

Prevalence of Temporomandibular Disorders in the Northern Finland Birth Cohort 1966.

To investigate the prevalence of temporomandibular disorders (TMD) in the 46-year-old cohort subjects from the Northern Finland Birth Cohort 1966 (NFBC 1966). Altogether, 1,962 subjects (1,050 women, 912 men) participated in a clinical medical and dental examination and responded to questionnaires in 2012 to 2013. The stomatognathic examination was performed according to a modified protocol of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Pearson's chi-square test and Fisher's exact test were used to analyze the signs of TMD between genders, and logistic regression models were used to analyze the relationship between self-reported pain associated with TMD and modified DC/TMD protocol (P < .05). Of the subjects available for analyses, 18.5% responded positively to the self-reported screening question for pain related to TMD. The most common signs of TMD were clicking in the temporomandibular joint (TMJ) (26.2%) and palpation pain in the masticatory muscles (11.2%). Women had signs of TMD more often than men (P < .05). The most common diagnosis was disc displacement with reduction (7.0%). Myalgia, arthralgia, disc displacement with reduction, and degenerative joint disease diagnoses were statistically significantly more common in women than in men (P < .05). The prevalence of TMD signs among the cohort subjects was 34.2%. The most common sign of TMD was clicking in the TMJ and the most common TMD diagnosis was disc displacement with reduction. The prevalence of TMD signs among the examined cohort subjects was 34.2%. TMD was diagnosed in women more often than in men. The results are comparable with other corresponding population-based studies in adults.

Diagnostic accuracy of magnetic resonance imaging and clinical signs of temporomandibular joint disorders: a 10-year research update review

Objectives To review the past 10 years of research in the diagnostic accuracy of magnetic resonance imaging (MRI) and clinical signs of temporomandibular joint (TMJ) disorders with pain, sound, and function limitation in the existing literature.

Displacement and tissue remodeling of temporomandibular joint disc

Sounding takes the highest prevalence of the signs of temporomandibular disorders (TMD). The well accepted theory of the mechanism for temporomandibular joint (TMJ) sounding is the internal derangement typically characterized by disc displacement. However, according to literature, there are approximately one third of asymptomatic joints in population had disc displacement, and, on the other hand, there are one fourth of TMJ sounding patients had not signs or very limited signs of disc displacement. Replacing the displaced disc to the normal position via methods like surgical operation did not achieve satisfactory long-term outcomes. In this review, we discuss and analyze the possible remodeling of the joint disc displacement diagnosed with imaging based on the anatomy and pathophysiology.

Symptoms and signs of temporomandibular disorders among elderly Vietnamese

Background: To assess the prevalence of the symptoms and signs of temporomandibular disorders (TMDs) and determine the prevalence of TMDs among elderly Vietnamese aged 65–74 years old. Methods: A cross-sectional study was conducted among 258 participants aged 65–74 years old (128 females and 130 males) using two strategies for TMD diagnosis: a clinical examination of the temporomandibular joint and its associated structures using the Diagnostic Criteria for Temporomandibular Disorders Axis I; and a set of 14 questions regarding TMD symptoms to obtain anamnestic data. Results: The prevalence of TMD symptoms was: headache 49.6%; temporomandibular joint noise 28.0%; orofacial pain 25.2%; jaw locking 3.1%; 62.5% of participants had at least one TMD symptom. Headaches were more prevalent in females than males ( p=0.009) and rural than urban residents ( p&lt;0.001). The most frequent signs were temporomandibular joint crepitus (50.4%), clicking (48.1%) and mouth-opening deviation (37.6%). Temporomandibular joint crepitus and mouth-opening deviation were more frequent among rural than urban ( p=0.024 and p&lt;0.001, respectively). TMD was found in 56.6% of the total sample. Of the TMD sufferers, 37.6% were diagnosed with disc displacement, 34.9% with degenerative joint disease, 3.5% with myalgia and 1.2% with arthralgia. Conclusions: More than half of elderly Vietnamese have at least one TMD symptom. TMD sounds were the most common clinical sign of TMD. There were no differences between the genders or place of residence and TMD diagnosis. Disc displacement and degenerative joint disease were most prevalent among elderly Vietnamese.

Análisis clínico de la prevalencia de trastornos témporomandibulares en niños de 8 a 12 años de edad de la Escuela Diego Abad de Cepeda de la ciudad de Quito

El presente estudio se realizó con el fin de conocer la prevalencia de trastornos témporomandibulares en niños de 8 a 12 años de la Escuela “Diego Abad de Cepeda” de la ciudad de Quito. La investigación se realizó en 228 niños que se distribuyeron en 128 mujeres y 100 hombres y bajo el método de observación se determinaron signos de trastornos témporomandibulares. Los trastornos que se evaluaron fueron dolor, limitación en apertura, deflexión, ruidos articulares y discrepancia entre relación céntrica y oclusión céntrica. El 49% de la población mostró al menos uno de los trastornos, siendo más prevalente en el sexo femenino con el 64%. Los trastornos más prevalentes en la población examinada fueron dolor con el 32% y ruidos articulares con el 25%. Los trastornos se encontraron con más frecuencia en aquellos niños que tuvieron uno o más hábitos perniciosos, apiñamiento y maloclusiones como mordida profunda, mordida abierta y mordida cruzada. Los resultados que se obtuvieron en el presente estudio nos ayudan a confirmar que los trastornos témporomandibulares pueden afectar también a los niños y nos impulsa a los odontólogos a aprender más sobre la articulación témporomandibular para saber tratarla adecuadamente.

TMD and orthodontics. A clinical guide for the orthodontist

It is my great honor to review TMD and orthodontics by Sanjivan Kandasamy, Charles Greene, Donald Rinchuse, and John Stockstill. These editors are all well known and have published numerous articles related to this topic. They assembled a team of world-renowned experts in this field to contribute to this book, including Daniel Laskin, Jeffrey Okeson, and many more. This collection presents evidenced-based answers for some of the most controversial topics in clinical orthodontics. During my oral medicine training, many patients with temporomandibular disorder (TMD) were referred from the orthodontic department. These patients typically asked 2 questions. The first question was when could they start orthodontic treatment? The other was whether they had to have orthodontic treatment to prevent a relapse of the TMD. These questions eventually got me interested in orthodontics, and I became an orthodontist. I still encounter patients who had “special” TMD treatment, including, for example, some kind of mandibular repositioning appliances, and they now have posterior open bite and are asking what would be the next step. TMD can be a confusing topic. There are many different opinions on everything from etiology to treatment. However, too many of these opinions are based purely on anecdotal experience and not on scientific evidence. This book consists of 10 chapters, including static and functional anatomy of the human masticatory system, etiology and classification, screening orthodontic patients for TMD, psychological considerations, sleep bruxism, orthodontics and TMD, idiopathic/progressive condylar resorption, management of TMD signs and symptoms, surgical management of TMJ problems, and medicolegal considerations. I found the chapter on orthodontics and TMD, written by Kandasamy and Rinchuse, to be especially helpful because it answered many questions that I had. The topics covered include occlusion, malocclusion and TMD, centric relation dilemma, functional occlusion and orthodontics, articulators for orthodontic diagnosis, TMJ sounds, internal derangements, and recapturing discs. All the information in this book is important and helpful; however, just for this chapter alone, this book is worthwhile to have. This book provides evidence-based information and guidance to orthodontists for managing TMD problems. I highly recommend it to every orthodontist who is dealing with TMD patients.

Signs of bruxism and temporomandibular disorders among patients with bipolar disorder

Background/Aim: There is an abundance of data regarding temporomandibular disorders (TMD) and bruxism specific to patients with bipolar disorder (BD). This study aimed to investigate the prevalence of TMD signs in subjects with and without BD. Material and Methods: The case group included 242 adult patients (103 men and 139 women) with BD and the control group included 187 subjects without BD (89 men and 98 women). The case and control groups were compared for the presence of bruxism and the signs of TMD including muscle and temporomandibular joint (TMJ) tenderness to palpation, limitation of maximum mouth opening, and TMJ sounds. Results: The frequency of at least one sign of TMD was significantly higher in patients with BD (191 ⁄242, 78.9%) than the control group (95 ⁄187, 50.8%) (p&lt;0.001). Statistically significant differences were found between the case and control groups in terms of joint pain on palpation (p&lt;0.05), masseter muscle pain on palpation (p&lt;0.01), joint clicks (p&lt;0.001) and limited mouth opening (p&lt;0.001). Bruxism was significantly higher in patients with BD (49.6%) than the control group (19.8%) (p&lt;0.001). Conclusions: Patients with BD appear to be more prone to having TMD signs and bruxism compared to the control group, but this comorbidity should be better understood by further studies.

Impact of temporomandibular disorders on the stomatognathic system in children.

BackgroundTo 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 MethodsForty 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).ResultsChildren 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).ConclusionsThe 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. Key words:Children, temporomandibular disorders electromyographic, bite force, ultrasound.