Tokyo Medical and Dental University Institutional Repository
Not a member yet
1399 research outputs found
Sort by
Get PDFA new rehabilitation (New-RH) program including respiratory muscle stretch gymnastics (RMSG) was developed to alleviate post-coronary artery bypass grafting pain (PCP). Effects on respiratory muscle function, pain, activities of daily living (ADL), mood and exercise capacity were investigated. Subjects were 16 consecutive patients undergoing median full sternotomy coronary artery bypass grafting (CABG), and were randomly divided into equal New-RH (S-group) and conventional therapy (C-group) groups. Rib cage dominant breathing was observed postoperatively in both groups. With preoperative tanΔVrc/Δ Vab, increases at 1-week postoperatively and decreases at discharge for S-group tended to exceed those of C-group (p > .05). Decreased maximum inspiratory and expiratory pressure status for functional residual capacity and percent forced expiratory volume in one second at discharge again only tended to be smaller for S-group (p > .05). S-group displayed significantly reduced pain around both scapulas at discharge (p = .049), and increased mean overall ADL and profile of mood states (POMS)/Vigor scores (p = .031 and p = .018, respectively). POMS/Tension-Anxiety scores at discharge for S-group were significantly smaller than those preoperatively (p = .025), and S-group displayed significantly increased distance walked over 6-minutes at discharge than C-group (p = .029). New-RH improves patient participation in exercise therapy and increases exercise capacity by reducing PCP, relieving anxiety and tension, and improving ADL.departmental bulletin pape
Get PDFThe aim of our study was to find symptomatic diagnostic factors for sideways displacement of the temporomandibular joint disc, compared with anterior or rotational disc displacement. A consecutive series of 2310 temporomandibular joints were examined with MRI to define the clinical signs and symptoms particularly related to sideways disc displacement compared to anterior disc displacement with logistic regression model. Bone change of the mandibular condyle and age were negatively related factors in differentiating cases with lateral disc displacement from anterior disc displacement without reduction. Range of mouth opening (over 40 mm) was a significant predictor (odds ratio 4.5865 for lateral disc displacement). This study suggested the wide opening of the mouth to become the predictor for the lateral disc displacement among the cases suspected to have disc displacement without reduction.departmental bulletin pape
Get PDFUsing a modal analysis system, we carried out a comparative assessment of the vibratory properties of the maxillary dentition of a human dry skull with a different distal end of a mouthguard. Mouthguards used in this study were: 1. a mouth-guard covering up to the third molar (8MG), 2. the second molar (7MG), 3. the first molar (6MG), and 4. the second premolar (5MG). To identify the modal shape, the frequency response functions were recorded on a fast Fourier transform analyzer from the force signal impacted with a vibration generator and the response signal picked up using a laser-doppler vibrometer. The transient response waves were obtained throughout the transient response simulation procedures after curve-fitting procedures. Mean decay rates (sec-1) of the transient response waves were calculated for the anteriors, premolars and molars, and compared among different sets of experimental conditions. The decay rates became lower as the distal end of a mouthguard was short. The decay rates with 8MG, 7MG and 6MG (anteriors) exceeded the no mouthguard's decay rate + 2S.D. values. These results imply that a mouthguard should distally cover up to the second molar at least to ensure efficient absorption and/or dispersion of a traumatic force.departmental bulletin pape
Get PDFThe purpose of this study was to evaluate the degree and amount of movement of the abutment tooth and denture base influenced by the direct retainer of distal extension removable partial denture and the location of functional loading, then to suggest direct retainer design with minimal adverse effect and with optimum functional loading location for residual tissue. The displacement of the abutment tooth and inclination of the denture base were determined, with 30 N as work load utilizing simulation model and strain guage system, about two types of direct retainers with mesial or distal rest and nine loading points on denture base. Displacement and inclination was determined with the one-way analysis of variance and Scheffe's multiple test was performed. The results revealed that type of direct retainer influenced on the magnitude rather than direction of the abutment tooth displacement. The distal displacement of abutment tooth was significantly less in Type M clasp (with mesial rest and connection) than in Type D clasp (with distal rest and connection) (p<0.05). The location of loading points influenced both of the magnitude and direction of the abutment tooth and denture base movement. Posterior and lingual loading resulted in significantly distal displacement of abutment tooth (p<0.05).departmental bulletin pape
Get PDFThis article describes the prosthodontic treatment for a patient with cerebral palsy, in which complete dentures were successfully stabilized using treatment dentures. A 69-year-old edentulous male with no medical complications or mental retardation presented to our clinic. Opening movement of the jaw was possible, but a conspicuous mandibular shift towards the right was observed. He had never received any prosthodontic treatment. Initially, treatment dentures with flat tables were fabricated to rectify his erratic mandibular movements. During the first 3 weeks, the treatment dentures functioned poorly. Eventually, the patient could make tapping movement to some degree and have a meal with less effort. Indentation marks from the cusps of the opposing maxillary denture could be clearly seen on the flat tables. After six weeks, as he did not complain of any pain, definitive dentures were fabricated. When flat table treatment dentures are used, it is considered that the mucosa provides information regarding the vertical stop and bite force. In addition, it is speculated that there is an increase in the response from masseter muscle. In the present case, flat tables were effective for rehabilitation of the mandibular movement.departmental bulletin pape
Get PDFUndecalcified mature enamel sections were used to observe the sequence of ultrastructural changes of enamel crystals and Streptococcus mutans biofilm in the early stages of caries. Human enamel blocks were incubated from 1 to 7 days with S. mutans suspension, and the pH of biofilm was measured. They were processed for light microscopic and transmission electron microscopy observations, and the number of bacteria located in the area adjacent to enamel surface counted. It was observed that the pH of the biofilm dropped to 4, after 1-day of incubation and the S. mutans number increased until 4-day. Round shaped enamel crystals were observed in the 2-day specimens and from the 4-day, images of crystals showing defects and perforations were visualized, becoming more defective along the incubation days. The length of time that the enamel was exposed to biofilm was the main factor for enamel crystals demineralization. Current in vitro caries induction system could standardize timerelated changes of the property of Streptococcus mutans biofilm and its relation to enamel crystals demineralization at the ultrastructural level, and thus provide a useful model for the evaluation of the effects of various anti-cariogenic agents.departmental bulletin pape
Get PDFUsing an in vitro model, we investigated the chronological effects of orthodontic force on the response properties of periodontal mechanoreceptors (PMRs) in the rat mandibular first molar (M1). Experimental tooth movement was obtained by attaching a super-elastic titanium-nickel (Ti-Ni) alloy closed coil spring from the mandibular incisors to the right M1. On 1, 2, 3, 4, 7 and 14 days after the appliances were set, three right mandibular molars were extracted and direct stimulation with von Frey hairs was applied to the PMRs remaining in the tooth sockets of right M1. Single unit discharges were recorded from the inferior alveolar nerve. Following results were obtained; (1) in the 1-, 2- and 3-day groups, the mechanical thresholds were significantly lower than those in the control group. In the 4-day group, the mechanical threshold was significantly higher than that of the 3-day group. (2) In the 3-, 4-, 7- and 14-day groups, the conduction velocities of Aβ units were lower than those in the control group. These results imply that orthodontic force applied to M1 induced functional changes in the PMRs within a few days, suggesting that the PMR seems to respond to orthodontic force at early stage of tooth movement.departmental bulletin pape
Get PDFMany high mountaineers die of acute mountain sickness in the high mountains of Nepal during their adventure. Most of them administer acetaminophen (AP) as an analgesic. Various cells with higher expression of cytochrome P-450 (CYP) would metabolize AP and lead to cellular impairment. CYP is a major enzyme system in the metabolism of xenobiotics in different organs of the human being including in Clara cells of the lungs. Clara cells contain the highest concentration of CYP. We injected AP to C57BL/6J mice to examine the toxicity of AP in Clara cells. In 8 hours Clara cells show more prominent apical protrusion with edematous smooth endoplasmic reticulum (sER), reduced secretary granules, and edema. We speculate that using AP in a high mountain area might be harmful for Clara cells being a trigger of high altitude sickness.departmental bulletin pape
Get PDFThe purpose of this study was to examine effects of a denture adhesive on masticatory functions for complete denture wearers considering the condition of denture-bearing tissues. Sixteen edentulous subjects wearing well-fitting complete dentures volunteered to participate in this study. According to the condition of denture-bearing tissues, subjects were divided into two groups; "good group" and "poor group". Maximum biting forces, masticatory performance, and electromyography of the masseter muscle during mastication were recorded with and without a denture adhesive. Durations of chewing burst and cycle, and coefficients of variation for these variables were calculated using electromyography recordings. Data were analyzed by using two-way repeated-measured ANOVA and paired t-test in order to assess the effect of the use of a denture adhesive. The use of the denture adhesive increased maximum biting force and provided rhythmic masseter muscle activity during mastication for both groups. Masticatory performance was improved and duration of chewing burst was decreased only for "poor group". It was concluded that the effects of the denture adhesive on masticatory functions were observed overall for both groups, and more significant for denture wearers with poor denture-bearing tissues than with good denture-bearing tisuues.departmental bulletin pape
Get PDFThe effects of high extracellular calcium (high Ca) in the local microenvironment on osteoclasts, osteoclast progenitors and stromal cells are not fully understood. We examined high Ca effect on osteoclastogenesis in mouse bone marrow cell culture. Mouse bone marrow cells were cultured for up to 6 days in the medium supplemented with 1,25(OH)2 vitamin D3 (D3). High Ca treatment at the early stage of culture (the initial 24 hours) reduced the number of tartrate resistant acid phosphatase-positive multinuclear cells (TRAP(+)MNCs). This treatment slightly up-regulated the mRNA expressions of receptor activator of NF-(B ligand (RANKL), RANK and osteoprotegerin (OPG). This inhibitory effect on the formation of TRAP(+)MNCs was recovered by RANKL. In contrast, high Ca treatment at the later stage of osteoclastogenesis (the last 2 days of culture) stimulated the formation of TRAP(+)MNCs, increased RANKL and RANK mRNA expressions and decreased OPG mRNA. High Ca at neither the early nor the later stage of culture affected the total number of adherent cells and the mRNA expression of alkaline phosphatase and osteopontin. In conclusion, high Ca affects osteoclastogenesis in a manner depending on the stage of osteoclastogenesis, which is partly mediated via the RANKL-RANK-OPG regulatory system.departmental bulletin pape