Lateral cephalometric analysis of asymptomatic volunteers and symptomatic patients with and without bilateral temporomandibular joint disk displacement

Few studies of dentofacial and orthodontic structural relationships relative to temporomandibular joint (TMJ) dysfunction have been reported. We undertook this investigation to determine any correlation of orthodontic and dentofacial characteristics with TMJ bilateral disc displacement. The population of patients was selected from a TMJ clinic where a control group of asymptomatic volunteers had been previously established and standardized. Differences in skeletal structural features were determined among three study groups: (1) asymptomatic volunteers with no TMJ disk displacement, (2) symptomatic patients with no TMJ disc displacement, and (3) symptomatic patients with bilateral TMJ disk displacement. Thirty-two asymptomatic volunteers without disk displacement (25 female, 7 male) were compared with the same number each of symptomatic patients without TMJ disk displacement and symptomatic patients with bilateral TMJ disk displacement. All subjects had undergone a standardized clinical examination, bilateral TMJ magnetic resonance imaging, and lateral cephalometric radiographic analysis. The groups were matched according to sex, TMJ status, age, and Angle classification of malocclusion. Seventeen lateral cephalometric radiographic cranial base, maxillomandibular, and vertical dimension variables were evaluated and compared among the study groups. The mean angle of SNB, or the intersection of the sella-nasion plane and the nasion–point B line (indicating mandibular retrognathism relative to cranial base), of the symptomatic patients-with-displacement group was significantly smaller than that in the asymptomatic volunteers and symptomatic patients without bilateral disk displacement (p \u3c 0.05). Female subjects showed smaller linear measurements of mandibular length, lower facial height, and total anterior facial height than male subjects in all three groups (p \u3c 0.05). The mean angle of ANB, or the intersection of the nasion–point A and nasion–point B planes (indicating retrognathism of mandible relative to maxilla), was significantly greater in female than in male subjects, in all groups (p \u3c 0.05). Symptomatic patients with bilateral disk displacement had a retropositioned mandible, indicated by a smaller mean SNB angle compared with that in asymptomatic volunteers and symptomatic patients with no disk displacement on either side. Lateral cephalometric radiographic assessment may improve predictability of TMJ disk displacement in orthodontic patients but is not diagnostic; nor does the assessment explain any cause-and-effect relationship. (Am J Orthod Dentofacial Orthop 1998;114:248-55.

Evaluation of temporomandibular disorders before and after orthognathic surgery: therapeutic considerations on a sample of 76 patients

Temporomandibular disorders may be associated with dental and facial malformations. The aim of this study is to record the prevalence of TMDs in patients scheduled for orthognathic surgery, reporting the development of TMDs and symptoms during the entire period of the treatment, and demonstrating the benefits of a team effort on this population. MATERIALS AND METHODS: Assessment of temporomandibular status was performed using the RDC/TMD criteria at T0 (prior to orthodontic therapy), T1 (3 months after the surgery), and T2 post-therapeutic cycle (6 to 12 months postoperatively). A total of 76 participants were included in the study; all the patients underwent surgical treatment: 12 had bilateral sagittal split osteotomy, 6 with condylar position devices; 64 had Le Fort I + bilateral sagittal split osteotomy, and 15 with condylar position devices. Results were evaluated with a paired-sample t-test and segmentation analysis. RESULTS: Forty-seven patients were affected by TMDs. At T0, 25 patients experienced TMJ pain, 27 had muscular pain, 31 suffered headaches, 42 had disc dislocation with reduction, and 5 were affected by disc dislocation without reduction. Thirty-five patients had occlusal signs of parafunctions, 8 reported tinnitus, and 7 dizziness. At T1, TMJ pain changed from 33.3% to 4.44%, muscular pain changed from 35.5% to 11.1%, headaches improved from 40% to 6.67%, and disc dislocation from 55.2% to 17.7%. Segmentation analysis highlighted improvement after therapy; 57 patients were considered recovered, 14 improved, none were considered stable, whereas 5 patients demonstrated some worsening, 3 of whom had not presented disc dislocation before surgery. At T2, 71 patients were considered completely recovered or improved. CONCLUSIONS: Our data indicates beyond any doubt that both functional status and pain levels related to TMDs can be significantly improved with a multi-disciplinary approach. We concluded that surgeon's intervention need to be modified in the presence of presurgical TMDs

Incidence of temporomandibular joint clicking in adolescents with and without unilateral posterior cross-bite: a 10-year follow-up study

Among different malocclusions, posterior cross-bite is thought to have a strong impact on the correct functioning of the masticatory system. The association between unilateral posterior cross-bite (UPCB) and temporomandibular joint (TMJ) clicking, however, remains still controversial. The aim of this study was to investigate whether the presence of UCPB during early adolescence increases the risk of reporting TMJ clicking after a long-term follow-up. A longitudinal survey design was carried out in a group of 12-year-old young adolescents, who were examined at baseline for TMJ clicking sounds and unilateral posterior cross-bite. After 10 years, 519 subjects could be reached by a telephone survey. Standardised questions were used to collect self-reported TMJ sounds and to determine whether participants had received an orthodontic treatment. Logistic regression analysis revealed a significant association between unilateral posterior cross-bite and subjectively reported TMJ clicking (odds ratio = 6·0; 95% confidence limits = 3·4-10·8; P < 0·0001). The incidence of TMJ clicking was 12%. At a ten-year follow-up, self-reports of TMJ clicking were significantly associated with the presence of UPCB at baseline, but not with the report of having received an orthodontic treatment. Within the limitation of this study, the presence of unilateral posterior cross-bite in young adolescents may increase the risk of reporting TMJ sounds at a 10-year follow-up. The provision of an orthodontic treatment, however, does not appear to reduce the risk of reporting TMJ sounds

Ortodontska terapija i temporomandibularni poremećaji

Orthodontic treatment has been variously cited both as a protective and harmful factor in temporomandibular disorders (TMD) etiology. Therefore, it is important to understand associations between different malocclusions, orthodontic treatment, and signs and symptoms of temporomandibular disorders (TMD). From the presented literature the suggestion that orthodontic treatment leads to TMD appears to be ill-founded. Clinical studies suggest that orthodontic treatment has little role to play in worsening or precipitating TMD when treated patients are compared with untreated individuals, with or without malocclusion, or when different types of orthodontic treatment are compared. A considerable reduction in signs and symptoms of TMD between the teenage period and young adulthood has been shown in some recent longitudinal studies.Ortodontska terapija često se navodi kao protektivni ili pak otežavajući čimbenik u etiologiji temporomandibularnih poremećaja. Zbog toga je vrlo važno razumjeti vezu između različitih ortodontskih anomalija i ortodontske terapije te znakova i simptoma temporomandibularnih poremećaja. Iz prezentirane literature proizlazi da je pretpostavka po kojoj ortodontska terapija dovodi do TMD-a neutemeljena. Klinička istraživanja pokazuju da ortodontska terapija igra malu ulogu u pogoršanju TMD-a kada se uspoređuju tretirani i netretirani ispitanici, oni s malokluzijama i bez njih ili kada se uspoređuju različite vrste ortodontske terapije. U nedavno objavljenim longitudinalnim istraživanjima navodi se znatno smanjenje simptoma i znakova TMD-a između tinejdžerske i rane odrasle dobi

Signs, Symptoms, and Morphological Features of Idiopathic Condylar Resorption in Orthodontic Patients : A Survey-Based Study

Background: Idiopathic condylar resorption (ICR) is an aggressive degenerative disease of the temporomandibular joint that is most frequently observed in teenage girls. However, no specific cause of ICR has been identified. To explore the specific causes of the onset and progression of ICR, we performed a survey-based study on ICR in orthodontic patients and described its subjective symptoms, clinical signs, and condylar morphological features. Methods: A total of 1735 participants were recruited from 2193 orthodontic patients. For each participant, subjective symptoms and clinical signs of temporomandibular disorders (TMDs) were evaluated through clinical examination and a questionnaire. Furthermore, three-dimensional computed tomography (CT) was performed to diagnose ICR. Results: Among the 1735 patients evaluated, ICR was present in two male and ten female patients. All 12 patients had maxillary protrusion and an anterior open bite. Four patients with ICR underwent orthodontic treatment. Based on CT findings, patients with ICR had significantly different condylar sizes and shapes from patients with TMDs alone. Conclusions: The coexistence of intrinsic and extrinsic factors, such as sex-hormone imbalance and a history of orthodontic treatment, might lead to the onset of ICR. We suggest that growing patients suspected of having ICR should undergo CT evaluation because CT findings may precede clinical symptoms and signs

Examination of temporomandibular disorders in the orthodontic patient: a clinical guide

The possible association between orthodontic treatment and temporomandibular disorders (TMD) is a topic of great interest in the current literature. The true role of orthodontic therapy on the etiology of TMD, however, is still uncertain. From the clinical prospective, a thorough examination of the stomatognathic system is always necessary in order to detect possible TMD signs and symptoms prior to the beginning of the orthodontic therapy. Caution should be exercised when planning, performing and finalizing orthodontics, especially in patients who with history of signs and symptoms of TMD. The clinician must always eliminate patient's pain and dysfunction before initiating any type of orthodontic mechanics. Muscle incoordination, unstable disc-condyle relationship and bone alterations are usual TMD conditions that can interfere with the presenting occlusal relationship. This article reviews these aspects and presents a detailed clinical guide for the examination of the orthodontic patient, considering aspects related to facial pain and dysfunction

JVA, Mastication and Digital Occlusal Analysis in Diagnosis and Treatment of Temporomandibular Disorders

Temporomandibular joint disorder (TMJ) is a complex and multifactorial functional disorder. Best approach in the treatment of TMJ disorders needs in detail proper diagnostic study. Joint vibration analysis (JVA) device, a new age technology and one of the most important diagnostic tools, is used for detecting intra-articular sound vibrations. Every type of vibration in different frequencies shows us the status of joint. Evaluation can be made after analyzing the results applying to a diagram. Like Combining of the sound vibration diagnostic techniques with other examination methods may be very meaningful in efforts of treating TMJ problems. Another diagnosis method is the evaluation of chewing movements. Best chewing efficiency is the most important purpose of masticatory system. Final product is a very important indicator for the efficiency of the mastication, and chewing pattern. T-Scan digital occlusal analyzing system is another important occlusal diagnostic instrument. Digital occlusal analysis system is currently the most powerful method of TMD clinics for treatment of patients with muscle pain dysfunction syndrome. Digital occlusal analysis system allows us to perform the MPDS treatments, splint and occlusal rehabilitation. The three important diagnostic systems are described in this chapter

Temporomandibular joint dysfunction and orthognathic surgery: a retrospective study

<p>Abstract</p> <p>Background</p> <p>Relations between maxillo-mandibular deformities and TMJ disorders have been the object of different studies in medical literature and there are various opinions concerning the alteration of TMJ dysfunction after orthognathic surgery. The purpose of the present study was to evaluate TMJ disorders changes before and after orthognathic surgery, and to assess the risk of creating new TMJ symptoms on asymptomatic patients.</p> <p>Methods</p> <p>A questionnaire was sent to 176 patients operated at the Maxillo-Facial Service of the Lille's 2 Universitary Hospital Center (Chairman Pr Joël Ferri) from 01.01.2006 to 01.01.2008. 57 patients (35 females and 22 males), age range from 16 to 65 years old, filled the questionnaire. The prevalence and the results on pain, sounds, clicking, joint locking, limited mouth opening, and tenseness were evaluated comparing different subgroups of patients.</p> <p>Results</p> <p>TMJ symptoms were significantly reduced after treatment for patients with pre-operative symptoms. The overall subjective treatment outcome was: improvement for 80.0% of patients, no change for 16.4% of patients, and an increase of symptoms for 3.6% of them. Thus, most patients were very satisfied with the results. However the appearance of new onset of TMJ symptoms is common. There was no statistical difference in the prevalence of preoperative TMJ symptoms and on postoperative results in class II compared to class III patients.</p> <p>Conclusions</p> <p>These observations demonstrate that: there is a high prevalence of TMJ disorders in dysgnathic patients; most of patients with preoperative TMJ signs and symptoms can improve TMJ dysfunction and pain levels can be reduced by orthognathic treatment; a percentage of dysgnathic patients who were preoperatively asymptomatic can develop TMJ disorders after surgery but this risk is low.</p

Review of temporomandibular joint pathology. Part I : classification, epidemiology and risk factors

Pathology of the temporomandibular joint (TMJ) affects an important part of the population, though it is not viewed as a public health problem. Between 3-7% of the population seeks treatment for pain and dysfunction of the ATM or related structures. The literature reports great variability in the prevalence of the clinical symptoms (6-93%) and signs (0-93%), probably as a result of the different clinical criteria used. In imaging studies it is common to observe alterations that have no clinical expression of any kind. Radiographic changes corresponding to osteoarthrosis are observed in 14- 44% of the population. Age is a risk factor, though with some particularities. In elderly patients there is an increased prevalence of clinical and radiological signs, though also a lesser prevalence of symptoms and of treatment demands than in younger adults. Approximately 7% of the population between 12 and 18 years of age is diagnosed with mandibular pain-dysfunction. Temporomandibular dysfunction (TMD) is more frequent in females. No clear relationship has been established between occlusal alterations and TMJ disease. Only disharmony between centric relation and maximum intercuspidation, and unilateral crossbite, have demonstrated a certain TMJ disease-predictive potential. Both local and systemic hyperlaxity has been postulated as a possible cause of TMD. Parafunctional habits and bruxism are considered risk factors of TMD with odds ratios (ORs) of up to 4.8. Psychophysiological theory holds stress as a determinant factor in myofascial pain. Genetic factors and orthodontic treatment have not been shown to cause TMD