PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “TEMPOROMANDIBULAR JOINT”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources

Postnatal development of the human temporomandibular joint. I. A histological study.

Temporomandibular joints from 61 humans, aged 2 days to 27 years, were examined histologically. Four layers of the condyle were studied in detail. The outermost layer was richly vascularised in new-borns but by 3 years of age it had become avascular and contained few cells. In neonates the cartilage layer constituted a large part of the condyle but soon decreased in thickness and by 5-6 years of age it constituted only a thin zone of the top of the condyle. In the proliferative zone, mitoses occurred up to 13-15 years of age. This zone then decreased in thickness; the number of cells decreased, while the amount of intercellular substance increased. At birth, the temporal component was flat and was lined by vascularised connective tissue which became richer in collagen with increasing age. The cartilage layer was lacking in the fossa but was present on the tuberculum. A proliferative zone in this cartilage could be seen up to the age of 17-18 years and cartilage having only few cells was found in adults. Remodelling processes were seen in all components of the joints. The significance of the remodelling seen in the fossa and on the mandibular neck is discussed with relation to condylar and periosteal growth of the mandible.

Adolescent↗

Mandibular excursions and maximum bite forces in patients with temporomandibular joint disorders.

PURPOSE: This study evaluated mandibular motion and bite force in patients with temporomandibular joint disorders after joint surgery. PATIENTS AND METHODS: Maximum voluntary mandibular motion, maximum excursion during mastication, and maximum bite force were examined in 25 female patients before temporomandibular joint surgery. Their pretreatment performance was compared with that at 6 weeks, 6 months, and 1 year after surgery, and with performance of 26 normal female volunteers. RESULTS: Before surgery, all of the patients' movements and bite forces were smaller than those of controls. One year after surgery, maximum interincisal opening increased significantly, but lateral excursion and protrusion remained unchanged. Maximum bite forces increased significantly and nearly reached control levels. CONCLUSIONS: Patients with severe restriction in temporomandibular joint function exhibit general improvements in some mandibular movements and in maximum bite force after surgical treatment.

Adolescent↗

Internal derangement related to osteoarthrosis in temporomandibular joint autopsy specimens.

In 127 temporomandibular joint autopsy specimens the position (superior 44%, partially anterior 22%, completely anterior 34%) and configuration of the disk (biconcave 56%, biconvex 10%, others 34%) were related to osteoarthrosis. All biconvex disks were positioned anteriorly and associated with osteoarthrosis. Biconcave disks were mostly positioned superiorly and associated with normal surfaces.

Adult↗

Surgery for recurrent dislocation of the temporomandibular joint.

Chronic dislocation of the temporomandibular joint has been dealt with by a variety of conservative and surgical maneuvers. Two surgical procedures, the temporomandibular arthroplasty, and the temporal fascia flap, with a capsulorraphy, are described as reliable methods for dealing with this problem.

Adult↗

An immunohistochemical and in situ hybridization study of the expression of tenascin in synovial membranes from human temporomandibular joints with internal derangement.

In samples of 27 human temporomandibular joints (internal derangement, ankylosis and control specimens) the distribution of immunoreactive tenascin was restricted to the walls of blood vessels, at the perineurium, and at the surface of the disc. Tenascin staining was intense in the stroma of hypertrophic synovial membranes, particularly on the surface of severely hypertrophic synovial membranes with inflammation, proliferation, irregular lining structures and new capillary growth. In situ hybridization of fresh discs and synovial membranes demonstrated that synovial cells as well as fibroblasts and endothelial cells expressed tenascin mRNA. The expression of tenascin mRNA was most evident in synovial cells. It is concluded that synovial cells in the synovial membrane produce tenascin in the diseased human temporomandibular joint.

Adult↗

Effects of experimentally induced inflammation on temporomandibular joint nociceptors in rats.

Response properties of nociceptors in the temporomandibular joint (TMJ) and surrounding area under experimental inflammation were investigated using an in vitro TMJ-nerve preparation in the rat. Nociceptive units (receptor and innervating nerve fiber) were classified into the following subtypes: Adelta-high-threshold mechanonociceptor (HTM), Adelta-polymodal nociceptor (POLY), C-HTM and C-POLY. In the inflamed joint, mechanical thresholds tended to be lower; however, the reaction to bradykinin was not identified as clearly as in control. Experimentally induced inflammation increased the proportion of heat-sensitive units and lowered heat threshold significantly. These results suggest that inflammation may sensitize nociceptors in the temporomandibular joint, and cause hyperalgesia and allodynia.

Action Potentials↗

Temporomandibular joint dysfunction syndrome in children.

Temporomandibular joint (TMJ) dsyfunction is described and a historical perspective of the disorder is presented. A review of research related to symptoms, incidence, correlates, and causes of TMJ dysfunction in children is presented. Factors regarding identification are discussed, and treatment options are outlined. The purpose of this article is to increase the awareness of school health personnel about a condition which traditionally has been considered an adult disorder.

Adolescent↗

Condylar replacement alone is not sufficient for prosthetic reconstruction of the temporomandibular joint.

Prosthetic reconstruction of the temporomandibular joint (TMJ) is a controversial method of treatment. This paper presents 2 cases that illustrate the problem with prosthetic reconstruction of the condylar head with no fossa reconstruction. In both cases, severe erosion and heterotopic bone formation occurred, and the patients underwent installation of total TMJ prostheses to replace the previous, partial ones.

Arthroplasty, Replacement↗

Corrected parasagittal direct CT imaging of the temporomandibular joint. With arthroscopic correlation.

Direct CT studies of the temporomandibular joints, using axial, coronal, and condylar axis corrections for parasagittal views perpendicular to the long axis of the condyle head to provide detailed CT examination of the bony structures and associated soft tissues. Images of selected patients are correlated with arthroscopic evaluation and treatment, yielding a unique perspective for evaluation of the imaging method and the joint itself. Based on these findings, a hypothetical mechanism of TMJ derangement is proposed.

Arthroscopy↗

Three-dimensional finite element analysis of the mandible and temporomandibular joint during vertical ramus elongation by distraction osteogenesis.

Distraction osteogenesis has been accepted as an alternative treatment modality for hypoplastic mandibles. Knowledge about the changes occurring in the temporomandibular joint region during mandibular distraction osteogenesis is, however, limited and controversial. Stress distribution in the temporomandibular joint region during unilateral vertical mandibular ramus distraction was studied using a finite element model. The finite element model was based on computed tomography scans and magnetic resonance imaging scans of a patient with unilateral hypoplasia of the right mandibular ramus caused by juvenile idiopathic arthritis. The character of stress distribution in the temporomandibular joint and mandible was analyzed quantitatively at different intervals of the vertical mandibular ramus elongation. During the distraction phase, the condyles, articular disks, and glenoid fossa regions were loaded with a differentiated stress pattern. The affected right condyle, disk, and fossa were submitted to increasing loads with increasing elongation compared with the contralateral temporomandibular joint. Loading on the unaffected left side shifted posteriorly and slightly laterally, because the left condyle was the center of rotation. The loading of the temporomandibular joint regions was low during the active distraction phase, although local areas were subjected to elevated peak stresses.

Arthritis, Juvenile↗

Postnatal development of the human temporomandibular joint. II. A microradiographic study.

Temporomandibular joint specimens from 22 subjects aged 1 month to 23 years were examined microradiographically. There occurred considerable interindividual variations in mineralization of the joints but nevertheless, systematic changes in mineralization were demonstrated during the periods of development and growth. A continuous compact bony layer formed early in the fossa and tubercle while the outer mineralized layer of the condyle consisted of calcified cartilage. A continuous bony layer around the periphery of the condyle was not fully developed before about 20 years of age. Growth of the articular tubercle was characterized by a spongy appearance of the bony layer over the tuberculum up to the end of puberty. No corresponding growth changes could be seen in the fossa. No mineralized parts could be seen in the disk or the fibrous layers of the articular surfaces.

Adolescent↗

Thickness of the articular soft tissue of the temporal component in temporomandibular joints with and without disk displacement.

OBJECTIVE: The purpose of this investigation was to test the hypothesis that temporomandibular joint disk displacement is associated with significant functional adaptive changes of the articular soft tissue of the articular eminence. STUDY DESIGN: Thirteen temporomandibular joint autopsy specimens with normal superior disk position and 12 with complete anterior disk displacement were cryosectioned, and sections were stained and photographed. At a magnification of x20 the soft tissue was measured (1) at the inflection point, (2) on the posterior slope, (3) at the apex, and (4) on the anterior slope of the articular eminence. RESULTS: Displacement of a deformed or nondeformed temporomandibular joint disk without perforation of the posterior disk attachment was associated with significantly increased thickness of the articulating soft tissue at the apex and on the posterior and anterior slopes of the articulating eminence. When disk displacement was associated with a perforation of the posterior disk attachment, the soft tissue was not significantly thicker than in joints with normal superior disk position. CONCLUSIONS: Increase in articulating soft tissue thickness is interpreted as an adaptive mechanism to maintain the condyle path and withstand excessive loading at interposition of the temporomandibular joint components. When the plasticity of the tissues is surpassed, the adaptation will be thwarted and replaced by tissue breakdown.

Adult↗

Postarthroscopy physical therapy management of a patient with temporomandibular joint dysfunction.

Arthroscopy of the temporomandibular joint (TMJ) is a new, relatively noninvasive surgical procedure for treating patients with TMJ dysfunction beyond nonsurgical management. The purpose of this commentary is to introduce a four-stage rehabilitation protocol currently used by the authors in the physical therapy management of a postarthroscopy TMJ patient with a diagnosis of bilateral capsular impingement and adhesions. The patient underwent diagnostic TMJ arthroscopy and the four-stage rehabilitation protocol. Stage I exercises to maintain mandibular mobility began in the recovery room. Stage II exercises consisted of hands-on and take-home stretching exercises. Stage III and IV exercises were completed to improve muscular function. The patient was discharged from physical therapy in a month with full range of motion and diminished pain and headaches. At 1-year follow-up, the patient demonstrated full range of motion without pain, further treatment, or medications.

Adult↗

Condylar fractures of the mandible. II. a radiographic study of remodeling processes in the temporomandibular joint.

Remodeling processes in 76 temporomandibular joints were studied on radiographs from 67 individuals sustaining condylar fractures. The indivuduals were ranged into four age groups: 3-11, 12-15, 16-19, and larger than or equal to 20 years of age at the time of fracture. The radiographic examinations were to be performed at the time of the trauma and 3, 6, 12, 24 and 36-48 months after the injury. In the age group 3-11 there was a complete return to normal skeletal relations in 20 of the 27 joints. Joints in teenagers (12-19) did not become normal to the same extent and in adults only minor remodeling was observed. In children the remodeling of the condylar process was extensive but indistinctly outlined. With increasing age there was a shift towards a more distinct apposition of bone on the posterior part of the condylar head visualized as a double contour. This contour first appeared in the late teens. In adults the remodeling processes seemed only to be part of the functional adjustment. Thus, the remodeling processes of the condylar process in a clinical sense may be looked upon as restitutional in children and adjusting or functional in adults. As regards the articular fossa, in children the remodeling processes were first observed as a double contour, of which the new one became more and more distinct, while the original roof gradually disappeared. The final results was a flattened fossa. In adults, a sclerosis of the roof of the fossa was found.

Adolescent↗

Personality and quantified neuromuscular activity of the masticatory system in patients with temporomandibular joint dysfunction.

Patients suffering from temporomandibular joint dysfunction syndrome (TMJS) and healthy volunteers were examined by means of MMPI questionnaire and electromyography (masseter, anterior temporal and anterior digastric muscles) at rest and during natural chewing. In response to mental load (arithmetic chain task) TMJS patients showed an increase in postural activity and partly rhythmical short augmentations above the mean level of this activity. Chewing potentials were considerably diminished in patients compared with controls. There was evidence for neurotic disorders in the patients MMPI (neurotic triad: higher scores on hypochondria, depression, hysteria). Significant differences (multivariate variance and discriminant analysis: P less than 0.001) between patients and controls were found both in the group with psychic signs (MMPI scales) and in the group of quantitative electromyographic parameters. However, a sufficient discrimination was only obtained by a combination of both parameter groups. The results show that probably psychic dynamics, as well as the structure of neuromuscular activity within the masticatory system, are important in the aetiopathogenesis of TMJS.

Adolescent↗

Histochemistry of the foetal human temporomandibular joint articular disc.

The human temporomandibular joint (TMJ) develops from mesenchymal cells that form condensations appearing as condylar and temporal blastema which give rise to the respective anterior and posterior regions of the TMJ articular disc. Previous reports have shown the foetal disc to be avascular, with a high content of organized collagen fibres and a lesser content of elastic fibres. In this study, the articular discs from TMJs of a human foetus at age 22 weeks were evaluated. At this stage of intrauterine (i.u.) development, the disc was found to be a highly cellular, biconcave structure with a dense arrangement of collagen fibres. Cell density was not uniform, with increased density in the intermediate band relative to the anterior and posterior bands. In contrast to earlier reports, capillaries containing red blood cells were observed along the inferior surface of the disc. Immunohistochemical staining for proteoglycans and glycosaminoglycans (GAGS) revealed abundant chondroitin sulphate proteoglycan (CSPG) and hyaluronic acid in the disc while relatively little amounts of dermatan sulphate proteoglycan II (DSPGII) were found. No keratin sulphate proteoglycan (KSPG) was detectable. Foetal human TMJ articular discs at this age were found to have morphology and regional characteristics similar to adult discs.

Capillaries↗

Estrogenic effect on swelling and monocytic receptor expression in an arthritic temporomandibular joint model.

Clinical presentation of temporomandibular joint (TMJ) disorders are more common in women and changes in the female hormone estrogen affect the level of swelling, pro-inflammatory cytokine release and pain in animal models of TMJ arthritis. Estrogen also modulates the expression of the CD16 receptor in vitro. This alters pro-inflammatory cytokine release in monocytes/macrophages when auto-antigens and arthritic factors bind the CD16 receptor. This study investigated the effects of various levels of estrogen on the intensity of inflammation and CD16 expression in a TMJ arthritic animal model. The experiments included rats that were intact or ovariectomized (OVX), eliminating the major source of estrogen output. A portion of the OVX animals had estrogen replaced with 17-beta estradiol (E2) using Alzet pumps. In OVX animals E2 levels were administered for 10 days to create an artificial estrus cycle or to simulate pregnancy. Following E2 treatment the rats were given an intra-articular TMJ injection of saline or complete Freund's adjuvant (CFA). CFA injection significantly increased TMJ swelling, stress induced chromodacryorrhea and attenuated food intake, thus indicating the adjuvant induced TMJ pain/inflammation. Removing endogenous E2 through OVX reduced CFA induced TMJ inflammation, whereas CFA increased the number of TMJ monocytes expressing the CD14 receptor equally in all groups irrespective of plasma E2 levels. Paradoxically, higher levels of E2 reduced the number of TNF-alpha positive, CD16+ and double labeled CD14+/CD16+ cells. The findings indicate that reduced plasma E2 levels attenuated CFA induced TMJ inflammation, whereas increasing E2 levels enhanced TMJ swelling in a dose dependent manner. Estrogenic group differences in CFA induced swelling were independent of TMJ CD14+, CD14+/CD16+ or CD16+ cell numbers suggesting E2 action on the CFA immune response primarily excluded CD16 receptor action.

Animals↗

Reactive oxygen species participation in experimentally induced arthritis of the temporomandibular joint in rats.

In the temporomandibular joint (TMJ), it has been hypothesized that mechanical stresses lead to the oxidative stress of articular tissues. It has also been postulated that cells pertinent to arthritis-including endothelial cells and synovial cells-when stimulated by mechanical stresses and/or pro-inflammatory cytokines, promote oxidative damage. To determine the involvement of reactive oxygen species (ROS) in the diseased joint, we studied the generation of ROS in synovial fluid (SF) from interleukin-1alpha (IL-1alpha)-induced TMJ arthritis by electron spin resonance (ESR) spectroscopy, using the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO). The TMJ arthritis was experimentally induced in rats by the injection of human recombinant IL-1alpha into the TMJ; control rats were treated with normal saline solution. We found that the detected radicals in the collected SF were identified as a 1:2:2:1 quartet, characteristic of the hydroxyl radical-DMPO spin adduct. The ESR signal intensity of the hydroxyl radical-DMPO spin adduct in the SF from IL-1-treated rats was significantly higher than that from the control rats (P < 0.01). The results of ESR study also showed that hydroxyl radical (HO*) was increased in a time-dependent fashion in the presence of superoxide anion radical (O2*-) scavenger superoxide dismutase (SOD); the formation of DMPO-HO* was strongly inhibited by the iron chelater deferoxamine. We could measure higher levels of free iron (Fe2- and Fe3-) in the SF from TMJ arthritis than in that from controls (P < 0.05). Analysis of the data obtained from the present study suggests that the HO* radical detected in SF from IL-1-induced TMJ arthritis is generated via a modified Haber-Weiss reaction (biological Fenton reaction) in which O2*- can subsequently result in the production of H2O2 through dismutation reaction by SOD. Thus, HO* may be generated from the reaction of resultant H2O2 with free iron ions. The results presented here provide the first evidence of involvement of ROS in IL-1-induced TMJ arthritis.

Analysis of Variance↗