vendex and Temporomandibular-Joint-Disorders

The aim of the present investigation was to evaluate the transverse displacement of the proximal segment and ramus rotation after a bilateral sagittal osteotomy (BSO) with rigid internal fixation (RIF) using bicortical LAG screws.. We conducted a retrospective review of 37 patients (14 males and 23 females, age range of 14 to 55 years) who underwent a mandibular advancement with BSO and RIF. Posteroanterior and lateral cephalometric radiographs were obtained 1 to 8 weeks before and 1 to 4 weeks after surgery. The transverse displacement and angulation of the proximal segments after surgery were measured on posteroanterior radiographs, using the best-fit method. The amount of mandibular advancement was compared with the amount of transverse displacement of the proximal segments.. In the 1 to 4-week postoperative period after a BSO, 36 of 37 subjects showed an increased transverse intergonion distance (5.6 mm) (P <.0001) and 35 of 37 patients showed an increased transverse interramus width (3.3 mm) (P <.0001). No correlation was found between mandibular advancement and transverse displacement of the proximal segment.. The study results indicate that transverse displacements of the proximal segments occur with BSO and RIF. The clinical impact on temporomandibular joint symptomatology or surgical relapse with such displacement was not assessed in the study. Future studies that address these issues may help to determine whether there is an association between proximal segment displacement and surgical relapse, temporomandibular dysfunction, or both.

Topics: Adolescent; Adult; Analysis of Variance; Bone Screws; Cephalometry; Female; Humans; Jaw Fixation Techniques; Male; Mandible; Mandibular Advancement; Mandibular Condyle; Middle Aged; Osteotomy; Radiography; Recurrence; Retrospective Studies; Temporomandibular Joint Disorders; Torque

These interventions usually aimed at the correction of the skeletal discrepancy by mandibular retrognatism with an advancement of the distal portion of the mandible after mandibular osteotomy. The position of the condyle is determined during the osteosynthesis with miniplates. Condyles are set back in relation with the supine position of the patient and the weakness of his (her) curarized muscle. All studies show that surgery of mandibular advancement causes a lateral, torque and backward movement of the condyles, all harmful to the condyles. Factors that predispose to condylar resorption are "the patient": a woman, young (between 15 and 40), high mandibular angle, with a history of temporo-mandibular disorders and surgical overload applied to the condyles. What are the possible solutions to avoid failures? Patient preparation before surgery and surgery simulation with an articulator, condylar position control during surgery, working with surgeons to achieve a condylar portion stabilization system (with the CAD), quickly set up a mobilization of the mandible by physiotherapy.

Topics: Adolescent; Adult; Age Factors; Computer Simulation; Computer-Aided Design; Dental Articulators; Female; Humans; Male; Mandible; Mandibular Advancement; Mandibular Condyle; Maxillary Osteotomy; Patient Care Planning; Physical Therapy Modalities; Retrognathia; Sex Factors; Temporomandibular Joint; Temporomandibular Joint Disorders; Torque; Young Adult

The aim of this study was to assess the influence of unilateral posterior crossbite on the electrical activity of the temporal and masseter muscles in patients with subjective symptoms of temporomandibular dysfunctions (TMD). The sample consisted of 50 patients (22 female and 28 male) aged 18.4 to 26.3 years (mean 20.84, SD 1.14) with subjective symptoms of TMD and unilateral posterior crossbite malocclusion and 100 patients without subjective symptoms of TMD and malocclusion (54 female and 46 male) aged between 18.4 and 28.7 years (mean 21.42, SD 1.06). The anamnestic interviews were conducted according to a three-point anamnestic index of temporomandibular dysfunction (Ai). Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany). Recordings were carried out in the mandibular rest position and during maximum voluntary contraction (MVC). Analysis of the results of the EMG recordings confirmed the influence of unilateral posterior crossbite on variations in spontaneous muscle activity in the mandibular rest position and maximum voluntary contraction. In addition, there was a significant increase in the Asymmetry Index (As) and Torque Coefficient (Tc), responsible for a laterodeviating effect on the mandible caused by unbalanced right and left masseter and temporal muscles.

Topics: Adolescent; Adult; Electric Impedance; Electromyography; Female; Humans; Male; Malocclusion; Masseter Muscle; Mastication; Muscle Contraction; Skin; Temporal Muscle; Temporomandibular Joint Disorders; Torque; Young Adult

The aim of this study was to analyze the immediate effect of resilient splints through surface electromyography testing and to compare the findings with the electromyographic profiles of asymptomatic subjects. The participants were 30 subjects, 15 patients with TMD (TMD Group) and 15 healthy subjects (Control Group), classified according to Research Diagnostic Criteria (RDC/TMD) Axis I. A resilient occlusal splint was made for each patient in the TMD Group from two mm thick silicon to cover all teeth. The EMG examination was performed before and immediately after installing the splint. Three tests were performed as follows: 1. Maximum Voluntary Contraction (MVC) using cotton rolls (standards test); 2. MVC in maximal intercuspation position; and 3. MVC with the splint in position. The EMG signal was recorded for five seconds. EMG indices were calculated to assess muscle symmetry, jaw torque, and impact. There was a statistically significant difference when comparing the results among the study groups. The symmetry index values in the Control Group were higher than the TMD Initial Group and similar to the TMD Group after the installation of the splint. The index values of torque were higher in TMD Initial Group when compared with the Controls. Impact values were lower than normal values in the TMD Initial Group and restored upon installation of the splint. The resilient occlusal splints may be used as complementary or adjunctive treatment of temporomandibular disorders.

Topics: Adolescent; Adult; Dental Occlusion, Centric; Electromyography; Humans; Mandible; Masseter Muscle; Muscle Contraction; Occlusal Splints; Orthodontic Appliance Design; Signal Processing, Computer-Assisted; Temporal Muscle; Temporomandibular Joint Disorders; Torque; Young Adult

The purpose of this study was to clarify which direction of the condylar path is advantageous for releasing TMJ intermittent lock. The subjects were ten patients with temporomandibular disorders (TMD) and intermittent lock caused by anterior displacement of disks without obvious medial or lateral displacement. The patients could not open their mouths fully in habitual opening but could open fully in an intentional winding opening with reduction of the anteriorly displaced disks (winding opening). The two kinds of movement at the kinematic condylar point were measured in each subject and compared. The length of the condylar path in winding opening was significantly larger than that in habitual opening. The affected side condyle of winding opening traced medio-inferior paths in the early part of the condylar translation in comparison with habitual opening. From the viewpoint of the condylar path, the medio-inferior direction of condylar translation is thought to be advantageous for releasing intermittent lock.

Topics: Adolescent; Adult; Dental Stress Analysis; Female; Humans; Joint Dislocations; Male; Mandibular Condyle; Middle Aged; Movement; Pilot Projects; Range of Motion, Articular; Temporomandibular Joint Disc; Temporomandibular Joint Disorders; Torque

Patient J.S., adult, female, presented with a morphologic skeletal asymmetry of the mandible resulting in a unilateral posterior crossbite, and a Class III skeletal discrepancy characterized by a hyperdivergent facial pattern (FMA, 30 degrees), retrognathic maxilla (SNA, 79 degrees), and compensating maxillary alveolar dental protrusion (1-NA, 7 mm). Maxillofacial surgery was declined. Orthodontic treatment, utilizing the Tweed-Merrifield edgewise technique, widened the maxillary dentition with a combination buccal crown torque and buccal root torque and with lingual crown torque in the mandibular posterior quadrant. Temporomandibular joint symptoms lessened and function improved with orthodontic treatment. The skeletal asymmetry improved and the patient was happy with the result, including her profile and her beautiful smile.

Topics: Adult; Cephalometry; Facial Asymmetry; Female; Humans; Malocclusion, Angle Class III; Mandibular Condyle; Orthodontic Appliances; Orthodontics, Corrective; Temporomandibular Joint Disorders; Torque

Topics: Contraindications; Crowns; Dental Arch; Dental Soldering; Humans; Incisor; Jaw Relation Record; Malocclusion, Angle Class II; Mandible; Maxilla; Molar; Open Bite; Orthodontic Appliance Design; Orthodontic Appliances, Functional; Orthodontic Brackets; Orthodontic Wires; Temporomandibular Joint Disorders; Time Factors; Torque

Topics: Contraindications; Dental Arch; Dentition, Mixed; Humans; Incisor; Malocclusion, Angle Class II; Mandible; Mandibular Condyle; Maxilla; Orthodontic Appliance Design; Orthodontic Appliances, Functional; Palatal Expansion Technique; Retrognathia; Temporomandibular Joint Disorders; Torque

The mandibular rotational angle and distance were measured during various movements of temporomandibular joint (TMJ) closed lock patients (17 women, 23.9 +/- 6.6 years). The measurements were compared with those of the healthy controls (18 women, 24.0 +/- 1.4 years) using the BioPAK system (BioResearch Inc. Milwaukee, USA), which can analyze mandibular rotational torque movements. During maximum mouth opening movement, the parameters of the patient group were significantly larger than those of the control group in horizontal plane (p < 0.05) but vice versa in frontal plane (p < 0.001). During protrusive movement, the parameters of patients were significantly larger than those of control group in frontal and horizontal plane (p < 0.01, p < 0.05). During lateral excursive movement to the affected side of patients, the parameters were significantly larger than those to the unaffected side in frontal plane (p < 0.05).

Topics: Adult; Case-Control Studies; Dental Stress Analysis; Female; Humans; Mandible; Mandibular Condyle; Movement; Range of Motion, Articular; Rotation; Temporomandibular Joint; Temporomandibular Joint Disorders; Torque

Topics: Adolescent; Adult; Ankylosis; Female; Humans; Jaw Fixation Techniques; Male; Mandibular Advancement; Mandibular Condyle; Middle Aged; Osteotomy; Range of Motion, Articular; Temporomandibular Joint Disorders; Torque

Topics: Adult; Bone Remodeling; Cephalometry; Female; Humans; Malocclusion, Angle Class II; Mandibular Condyle; Orthodontics, Corrective; Temporomandibular Joint Disorders; Torque; Torsion Abnormality