Biomechanical calculation of human TM joint loading with jaw opening.

A three-dimensional, static mathematical calculation of the stomatognathic system was done to predict total temporomandibular joint (TMJ) loading at different levels of jaw opening. The model assumed that muscle forces acting on the mandible could be simulated by a combination of contractile components (CCs) and elastic components (ECs) and that static equilibrium existed within the body of the mandible. The model also imposed the constraint that any generated joint reaction force would act on the centre of the condyle.

Blood pressure biofeedback treatment of white-coat hypertension.

Objective: The objective of the study was to compare blood pressure (BP) biofeedback treatment (BF) effects between white-coat hypertension and essential hypertension.

Methods: Fifteen white-coat hypertensive out-patients and 23 essential hypertensive out-patients were randomly assigned to groups A or B. Subjects in group A underwent BF once a week for a total of four sessions.

Effect of cold pressor stimulation (4 degrees C) on human masseter muscle haemodynamics during and after sustained isometric contraction.

The effect of cold pressor (CP) stimulation and sustained isometric contraction on the blood volume of the right masseter muscle was examined in seven healthy males, who performed 1 min of isometric jaw clenching at 50% of their maximum voluntary contraction without, with and again without a 4 degrees C CP stimulation. Total haemoglobin was measured in the masseter before, during and after the contraction task using near-infrared spectroscopy. CP stimulation during the isometric contraction diminished the magnitude of the contraction-induced decrease of blood volume when compared to the trials without CP stimulation.

Cold pressor stimulation effect on hemodynamic changes following sustained isometric contraction in human jaw-closure muscles.

It is postulated that an altered adrenergic response pattern may be associated with chronic muscle pain states. To evaluate this hypothesis, one must fully understand the effect of an adrenergic activation on masticatory muscle blood flow under various conditions. This study evaluated the effect of a 12 degrees C cold pressor stimulation (a mild adrenergic activator), applied to the hand-forearm area, on intramuscular hemodynamics in the human masseter and temporalis muscles following a sustained isometric contraction.

Alexithymic traits as predictors of difficulties with adjustment in an outpatient cohort of expatriates in Tokyo.

The purpose of this study was to examine whether alexithymic characteristics, which are thought to be related to poor coping with stress, would be associated with variables thought to reflect adjustment to life abroad. The subjects were 56 expatriates living in Tokyo, Japan. The Expatriate Adaptation Inventory, the Toronto Alexithymia Scale, and the Social Support Questionnaire of the Stress and Coping Inventory were given to the subjects.

[Recurrent bleeding tendency due to factor VIII inhibitor during therapy for bullous pemphigoid].

A 67-year-old woman with bullous pemphigoid (who had no history of hemorrhagic disease or blood transfusion) experienced extensive ecchymosis of the trunk and extremities and marked submucosal bleeding of the pharynx and larynx with risk of obstruction and suffocation. This bleeding tendency was the manifestation of a coagulation disorder due to factor VIII inhibitor. Immunosuppressive therapy, steroid pulse therapy, prednisolone (PSL), and cyclophosphamide (CPA) alleviated the bleeding and yielded negative assays for factor VIII inhibitor.

Blood pressure biofeedback treatment, organ damage and sympathetic activity in mild hypertension.

Background: Although biofeedback treatment is reported to be useful for patients with mild hypertension as an adjunct to medication, it is not certain whether the presence of organ damage affects its efficacy. The aim of this study is to clarify the clinical effects of biofeedback on mild hypertension in the absence and presence of organ damage.

Methods: Eleven mildly hypertensive outpatients without damage to the heart, brain, retina or kidney (4 men and 7 women), aged 40-65 years, and 11 mildly hypertensive outpatients with target organ damage and matching variables for age, sex and medication were included in this study.

Haemodynamic responses in chronically painful, human trapezius muscle to cold pressor stimulation.

The aim was to compare haemodynamic responses in trapezius muscles to cold pressor stimulation in individuals with localized trapezius myalgia and asymptomatic controls. Nine males with chronic localized pain in the trapezius (mean age, 23.2 years) and nine male controls (mean age, 24.

Direct adenovirus-mediated gene delivery to the temporomandibular joint in guinea-pigs.

Adenovirus vector system is expected to be useful for direct gene therapy for joint disease. This study first sought to confirm that foreign genes can be transferred to articular chondrocytes in primary culture. Next, recombinant adenovirus vectors harbouring beta-galactosidase gene (LacZ) was injected directly into the temporomandibular joints of Hartley guinea-pigs to clarify the in vivo transfer availability of the adenovirus vectors.

Haemodynamic changes in human masseter and temporalis muscles induced by different levels of isometric contraction.

This study evaluated the influence of low contraction forces on intramuscular haemodynamics in human masseter and temporalis using near-infrared tissue spectroscopy. This method allowed the intramuscular haemoglobin (Hb) to be assessed dynamically before, during and after a 5, 15, 25 and 100% maximum voluntary contraction (MVC). Twenty volunteers, 10 males and 10 females, without pain or dysfunction in the masticatory system were included in this study.

The effects of sustained incisal clenching on the temporomandibular joint space.

Objective: To determine the effect of sustained incisal clenching on the width of the temporomandibular joint space.

Methods: Nine normal subjects clenched on an anterior appliance for 10 min at 49 N. Sagittal tomograms were obtained during comfortable closure in the intercuspal position (ICP) (ICP-Before), comfortable closure on bite force transducer without clenching (BFT-Before), start of clenching (BFT-0), end of 5 min clenching (BFT-5), end of 10 min clenching (BFT-10), comfortable closure on the bite force transducer immediately after clenching (BFT-After) and comfortable closure in ICP after clenching (ICP-After).

Effect of occlusal appliances and clenching on the internally deranged TMJ space.

Aims: Stabilization appliances and mandibular anterior repositioning appliances have been used to treat patients with internal derangement of the temporomandibular joint (TMJ) based on the assumption that these appliances work by decompressing the TMJ. The purpose of this study was to indirectly test this assumption.

Methods: Bilateral TMJ tomograms of 7 subjects with unilateral anterior disc displacement without reduction (ADDwor) were taken during comfortable closure and during maximum clenching in maximum intercuspation; tomograms were also taken with the 2 types of occlusal appliances in use.

Quality of life assessment of bone-anchored fixed partial denture patients with unilateral mandibular distal-extension edentulism.

Statement Of Problem: Dental implants are expanding their use among partially edentulous patients. However, whether implants can promote the quality of life (QOL) of these patients has not been sufficiently examined.

Purpose: This study compared the QOL level among implant denture, removable partial denture, and no restoration patients with distal extension type unilateral mandibular edentulism.

Effect of intravenous infusion of a beta-adrenergic blocking agent on the haemodynamic changes in human masseter muscle induced by cold-pressor stimulation.

Eight healthy non-smoking males (mean age: 24.1 +/- 1.1 years) without any history of chronic muscle pain and migraine participated in this study.

Connective tissue growth factor induces the proliferation, migration, and tube formation of vascular endothelial cells in vitro, and angiogenesis in vivo.

Connective tissue growth factor (CTGF) is a novel cysteine-rich, secreted protein. Recently, we found that inhibition of the endogenous expression of CTGF by its antisense oligonucleotide and antisense RNA suppresses the proliferation and migration of vascular endothelial cells. In the present study, the following observations demonstrated the angiogenic function of CTGF in vitro and in vivo: (i) purified recombinant CTGF (rCTGF) promoted the adhesion, proliferation and migration of vascular endothelial cells in a dose-dependent manner under serum-free conditions, and these effects were inhibited by anti-CTGF antibodies; (ii) rCTGF markedly induced the tube formation of vascular endothelial cells, and this effect was stronger than that of basic fibroblast growth factor or vascular endothelial growth factor; (iii) application of rCTGF to the chicken chorioallantoic membrane resulted in a gross angiogenic response, and this effect was also inhibited by anti-CTGF antibodies.

Detection of specific antibodies against human cultured chondrosarcoma (HCS-2/8) and osteosarcoma (Saos-2) cells in the serum of patients with osteoarthritis of the temporomandibular joint.

To find specific humoral antibodies in sera from patients with temporomandibular joint (TMJ) osteoarthritis (OA), an immortal human chondrocyte (HCS-2/8) and osteoblast (Saos-2) cell line derived from a chondrosarcoma and an osteosarcoma, respectively, were used as source proteins of human antigens. Patients with chronically painful TMJ OA (n = 18) but no other joints symptoms were selected from a consecutive series of patients with temperomandibular disorders and sex-matched asymptomatic controls (n = 8) were also recruited. Cellular proteins of the HCS-2/8 and Saos-2 cells were subjected to Western blotting with the OA and control sera as probes.

Assessment of ego state in anorexia nervosa and bulimia nervosa.

To clarify the effects of ego states on anorexia nervosa (AN) and bulimia nervosa (BN), the questionnaire of the Tokyo University Egogram (TEG) with critical parent, nurturing parent, adult, free child and adapted child scales was administered to 32 female AN patients aged 14 to 32 years (mean age 20 years) and 49 female BN patients aged 14 to 33 years (mean age 23 years). The scores on the critical parent and adapted child scales for AN were significantly lower than those for BN. A multiple logistic regression analysis including all of the TEG scales, age, duration of illness and education showed that the adapted child scale significantly discriminated between AN and BN.

Effect of intravenous infusion of an alpha-adrenergic blocking agent on the haemodynamic changes in human masseter muscle induced by cold pressor stimulation.

This study evaluated the effect of intravenous infusion of a non-selective alpha-adrenergic blocking agent on masseter muscle haemodynamics induced by 4 degrees C cold pressor stimulation (CPS) of the right foot and ankle, which reportedly evokes a rapidly increasing sympathetic nerve activity in human skeletal muscle. Nine healthy non-smoking males (mean age 23.7+/-2.

Cyclic mechanical stress induces extracellular matrix degradation in cultured chondrocytes via gene expression of matrix metalloproteinases and interleukin-1.

To clarify the mechanism of cartilage degradation induced by mechanical stress, we investigated the influence of cyclic tension force (CTF) on the metabolism of cultured chondrocytes. The chondrocytes were exposed to CTF using a Flexercell strain unit. Five or 15 kPa of high frequency CTF significantly inhibited the syntheses of DNA, proteoglycan, collagen, and protein.

Clinical predictability of temporomandibular joint disc displacement.

Single items from a typical clinical examination have proved disappointing in their predictive value for temporomandibular joint (TMJ) disc displacement. Only one criterion (the 12 o'clock) is used to diagnose normal disc position. According to this criterion, the posterior band of the disc should be located at the top of the condyle, at the 12 o'clock position.

Concurrent cervical and craniofacial pain. A review of empiric and basic science evidence.

Because many patients present themselves for treatment with both craniofacial and craniocervical pain, 2 questions arise: (1) What are the sensory and motor consequences of dysfunction in either of these areas on the other? (2) Do craniofacial and craniocervical pain have a similar cause? These questions formed the impetus for this review article. The phenomenon of concurrent pain in craniofacial and cervical structures is considered, and clinical reports and opinions are presented regarding theories of cervical-to-craniofacial and craniofacial-to-cervical pain referral. Because pain referral between these 2 areas requires anatomic and functional connectivity between trigeminally and cervically innervated structures, basic neurophysiologic and neuroanatomic literature is reviewed.

Cold pressor stimulus temperature and resting masseter muscle haemodynamics in normal humans.

Cold pressor stimulation reportedly increases sympathetic nerve activity in human skeletal muscles. This study examined the effect of cold pressor stimulation on the resting haemodynamics of the right masseter muscle in normal individuals, using near-infrared spectroscopy. Nine healthy non-smoking males with no history of chronic muscle pain or vascular headaches participated.

Diagnostic value of 4 criteria to interpret temporomandibular joint normal disk position on magnetic resonance images.

Objective: This study was undertaken to evaluate different criteria to establish normal disk position on magnetic resonance images.

Study Design: Magnetic resonance image findings of 137 consecutive patients with temporomandibular disorders and 23 asymptomatic volunteers were used in this study. Three calibrated observers interpreted the images individually.

Psychosocial factors influencing the short-term outcome of antithyroid drug therapy in Graves' disease.

Objective: Although psychological stress and smoking have been proposed as factors contributing to Graves' disease, their independent roles in the course of this disease have not been determined. We assessed the association between the course of Graves' disease and psychosocial factors by using multivariate analysis.

Methods: We investigated the association between the short-term outcome of Graves' disease (assessed 12 months after the beginning of antithyroid drug therapy) and stressful life events, daily hassles, smoking, drinking habits, coping skills, and social support (before and 6 months after beginning therapy) in 230 patients (182 women and 48 men) with newly diagnosed Graves' disease, using a logistic regression model.