• Structural Engineering and Mechanics
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• v.74 no.6
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• pp.723-735
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• 2020

This study is reported the adhesion failure in adhesive bonded composite and specifically for the T-joint structure. Three-dimensional finite element analysis has been performed using a commercial tool and the necessary outcomes are obtained via an eight noded solid element (Solid 185-element) from the library of ANSYS. The structural analysis input has been incurred through ANSYS parametric design language (APDL) code. The normal and shear stress distributions along different layers of the joint structure have been evaluated as the final outcomes. Based on the stress distributions, failure location in the composite joint structure has been identified by using the Tsai-Wu stress failure criterion. It has been found that the failure index is maximum at the interface between flange and web part of the joint (top layer) which indicates the probable location of failure initiation. This kind of failures are considered as adhesion failure and the failure propagation is governed by strain energy release rate (SERR) of fracture mechanics. The different adhesion failure lengths are also considered at the failure location to calculate the SERR values i.e. mode I fracture (opening), mode II fracture (sliding) and mode III fracture (tearing) along the failure front. Also, virtual crack closure technique (VCCT) principle of fracture mechanics steps is used to calculate the above said SERRs. It is found that the mode I SERR is more dominating compared to other two modes of failure for the joint considered. Finally, the influences of various parametric (geometrical and material) effect on SERR of the joint structure are evaluated and discussed in details.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.5
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• pp.453-457
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• 2006

This study was designed to investigate the effect of intra-articular injection of hyaluronic acid for the treatment of internal derangements of the temporomandibular joint(TMJ). Sixteen patients with internal derangements of TMJ in 1 male and 15 females aged 68 to 18 years comprised the study material. The patients' complaint was limited mouth opening and pain during function. Patients were divided into 3 groups(articular disc displacement with reduction, articular disc displacement without reduction, osteoarthritis group). The preauricular area was disinfected anesthetized locally with 2% lidocaine hydrochloride. Arthrocentesis was performed. Hyaluronic acid(1.5 ㏄) was then injected into the superior compartment of the TMJ. Active range of motion exercises were instituted at approximately 24 hours postoperatively. Antibiotics and NSAID, three times daily by mouth, was prescribed for 3 days. Clinical evaluation of the patients was done before the procedure, immediately after the procedure, final follow-up visit postoperatively. Pain during function was assessed using visual analog scales(VAS). Maximal mouth opening was recorded as a distance between upper incisal edge and lower incisal edge. Intra-articular injection of hyaluronic acid caused significant reduction of pain during function, significant increase of maximal opening range. These findings suggest that intra-articular injection of hyaluronic acid is useful for decreasing patient reports of pain while increasing functional mobility of the mandible in internal derangements of the TMJ.

• Steel and Composite Structures
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• v.16 no.2
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• pp.187-201
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• 2014

A new through-beam connection system for a concrete filled steel tube column to RC beam is proposed. In this connection, there are openings on the steel tube while the reinforced concrete beams are continuous in the joint zone. The moment and shear force at the beam ends can be transferred to column by continuous rebar and concrete. The weakening of the axial load and shear bearing capacity due to the opening of the steel tube can be compensated by strengthening steel tube at joint zone. Using this connection, construction of the joint can be made more convenient since welding and hole drilling in situ can be avoided. Axial compression and reversed cyclic loading tests on specimens were carried out to evaluate performance of the new beam-column connection. Load-deflection performance, typical failure modes, stress and strain distributions, and the energy dissipation capacity were obtained. The experimental results showed that the new connection have good bearing capacity, superior ductility and energy dissipation capacity by effectively strengthen the steel tube at joint zone. According to the test and analysis results, some suggestions were proposed to design method of this new connection.

• Computers and Concrete
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• v.10 no.5
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• pp.469-487
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• 2012

This paper presents a study on the behaviour of the joints of segmental concrete bridges with external prestressing, focusing on the structural response of dry non-epoxied joints with shear keys. A Finite Element joint model to study such structures is validated modelling eight concrete panel tests. The most important feature of this model is that it has been validated with experimental tests on concrete panels which were specifically designed to fail in shear. Interface elements are used to reproduce the non linear behaviour of the joint and parameters deduced from the tests are used to define the constitutive law of these elements. This joint model is of great importance because it will permit the development of a structural model that faithfully reproduces the behaviour of these structures under combined flexure and shear and the study of its global behaviour after the opening of the joints. Interesting conclusions about the behaviour of the dry joints, about the contribution of the different mechanisms transferring shear (friction and cohesion) and about the shear stress distribution in the joint have been reached.

• Physical Therapy Korea
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• v.6 no.3
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• pp.94-109
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• 1999

The purposes of this study were to assess the effect of therapeutic exercise and to offer an approach to the physical therapy and rehabilitation procedure of the temporomandibular joint (TMJ) following surgery. In this research, 42 patients with TMJ surgery were assigned one of two groups. The experimental group included 21 patients who performed therapeutic exercise, and the control group included 21 patients who did not perform therapeutic exercise. Conservative therapy such as an ice pack, a hot pack, and pulsed ultrasound was applied to both groups. Treatment was applied twice a day during the admission period and, after discharge, everyday for six weeks. Visual analogue scale (VAS), incisal biting force, and joint ROM were measured before surgery and at 30 days after surgery. The results were as follows: VAS (p<0.05), mouth opening (p<0.01), lateral excursion to unaffected side (p<0.05), and protrusion (p<0.05) between experimental group and control group showed statistically significant differences. Incisal biting force and lateral excursion to affected side between experimental group and control group showed no statistically significant difference.

• Imaging Science in Dentistry
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• v.48 no.2
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• pp.147-152
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• 2018

Synovial chondromatosis is a rare metaplastic disease affecting the joints, including the temporomandibular joint (TMJ). Since its symptoms are similar to those of temporomandibular disorders, a careful differential diagnosis is essential. A 50-year-old male patient was referred with the chief complaint of pain and radiopaque masses around the left TMJ on panoramic radiography. Clinically, pre-auricular swelling and resting pain was found, without limitation of mouth opening. On cone-beam computed tomographic images, multiple calcified nodules adjacent to the TMJ and bone proliferation with sclerosis at the articular fossa and eminence were found. T2-weighted magnetic resonance images showed multiple signal-void nodules with high signal effusion in the superior joint space and thickened cortical bone at the articular fossa and eminence. The calcified nodules were removed by surgical excision, but the hypertrophic articular fossa and eminence remained. A histopathological examination confirmed the diagnosis. The patient was followed up few months later without recurrence.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.11 no.2
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• pp.62-66
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• 2015

Temporomandibular joint dislocation causes considerable pain, discomfort, and swelling. The anatomic construction of the articular fossa and the eminentia articularis may predispose to dislocation, and weakness of the connective tissue forming the capsule is believed to be a predisposing factor. The capsule may be stretched and, more rarely, torn. Dislocation may be unilateral or bilateral and may occur spontaneously after stretching of the mouth to its extreme open position, such as during a yawn or during a routine dental operation. Manual reduction with the patient under muscle-relaxing condition or anesthesia is recommended method. After the reduction of an acute dislocation, immobilization of the jaw is recommended to allow the stretched and sometimes torn capsule to heal, thus preventing recurrence. A Barton's bandage may be applied for 2 to 3 weeks to prevent the patient from opening the jaw too wide. But, it results in recurrent dislocation in the neurologically disabled patient, because of loose intermaxillary fixation. This is a case report about management of recurrent temporomandibular joint dislocation by multiple loop wirings and intermaxillary elastics in cerebrovascular accident patient.

• Physical Therapy Rehabilitation Science
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• v.9 no.4
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• pp.244-251
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• 2020

Objective: Physical therapy techniques are required for patients with temporomandibular joint disorder (TMD), but the effects of treatment have not been compared. Therefore, effects of transcutaneous electrical nerve stimulation (TENS) and low level laser (LLL), which are most commonly used interventions, were compared. Design: Randomized controlled trial. Methods: Thirty-six participants with pain in the temporomandibular joint were enrolled, and 12 participants were randomly assigned to either the TENS group, LLL group, or placebo group. Each intervention was performed for a total of 6 sessions for 2 weeks. For the evaluation of the participants, the mouth opening (MO), pressure pain threshold (PPT), and stress were measured at three time periods: baseline, post-test, and follow-up at 2 weeks. Results: Significant interaction between groups according to each evaluation point was found only in PPT-masseter (p<0.05). The evaluation time point at which a significant difference appeared was at the post-test and follow-up at 2 weeks time periods. As a result of the post-test, the LLL group showed a significant improvement compared to the TENS group (p<0.05), and at 2 weeks follow-up, the TENS group showed a significant improvement compared to the placebo group (p<0.05). Conclusions: In this study, an experiment was conducted to compare the treatment effects when TENS, LLL, and placebo were given to patients with TMD. In addition, by quantitatively presenting the effect size of each treatment, this study suggests clinical use of TENS and LLL treatment for TMD.

• Journal of Oral Medicine and Pain
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• v.11 no.1
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• pp.19-27
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• 1986

Registration of the mandibular movement in patients with temporomandibular joint noise (clicking and/or crepitus) was performed using one of mandibular tracking devices(SAPHON VISI-TRAINER CII,Tokyo Shizai-sha Inc.,Japan). The obtained results were follows : 1. In many cases, the movement pattern of light emitting diode(LED) attached on the mandibular midline showed lateral deviation from a vertical reference line which was pronounced in association with TMJ noise during opening and closing. 2. In patients with unilateral TMJ noise the mandibular midline usually towards the side demonstrating TMJ noise during opening. 3. A distinct V-shaped discontinuity in the trace of velocity of mandibular movement was found at the point of the TMJ noise. 4. In patients with TMJ noise the velocity of mandibular movement at the point of the TMJ noise was decreased rapidly. 5. In several cases, TMJ noise could be eliminated by traning of Rocabado`s control of TMJ rotations.

• Imaging Science in Dentistry
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• v.44 no.4
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• pp.293-299
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• 2014

Purpose: This study was performed to find the relationship between pain and joint effusion using magnetic resonance imaging (MRI) in temporomandibular disorder (TMD) patients. Materials and Methods: The study subjects included 232 TMD patients. The inclusion criteria in this study were the presence of spontaneous pain or provoked pain on one or both temporomandibular joints (TMJs). The provoked pain was divided into three groups: pain on palpation (G1), pain on mouth opening (G2), and pain on mastication (G3). MRI examinations were performed using a 1.5-T MRI scanner. T1- and T2-weighted images with para-sagittal and para-coronal images were obtained. According to the T2-weighted image findings, the cases of effusions were divided into four groups: normal, mild (E1), moderate (E2), and marked effusion (E3). A statistical analysis was carried out using the $X^2$ test with SPSS (version 12.0, SPSS Inc., Chicago, IL, USA). Results: Spontaneous pain, provoked pain, and both spontaneous and provoked pain were significantly related to joint effusion in TMD patients (p<0.05). However, among the various types of provoked pain, pain on palpation of the masticatory muscles and TMJ (G1) was not related to joint effusion in TMD patients (p>0.05). Conclusion: Spontaneous pain was related to the MRI findings of joint effusion; however, among the various types of provoked pain, pain on palpation of the masticatory muscles and TMJ was not related to the MRI findings of joint effusion. These results suggest that joint effusion has a significant influence on the prediction of TMJ pain.