The purpose of the present study was to examine the effects of four dentin primers with the ester structure of the methacrylate and polyhydric alcohol on the sensitivity of the dentin electrophysiologically.
In this study, four types of primer-2-hydroxyethyl methacrylate (2-HEMA), high purity glyceryl mono-methacrylate (p-GM), tri-ethylene glycol mono-methacrylate (TEGMA), and polyethylene glycol mono-methacrylate (PEGMA)-were used. Under pentobalbitarl anesthesia, to record the action potential from the pulp branch with the platinum electrode, a class V cavity, approximately 1 mm in diameter and 1 mm in depth, was prepared in the dentin facial surface of the lower central incisal tooth of the rabbit with #6 round bar mounted on the dental electric engine with a water coolant.
The class V cavity was mechanically stimulated with the brush corn when it was washed with EDTA, was applied with the primer, and was rinsed with a normal saline solution. The frequency of the generated action potential under priming and rinsing was calculated as a percentage of the frequency of the action potential that had generated when the cavity was stimulated under conditioning with EDTA.
Following results were obtained; 1) significant difference between control and priming, and between priming and rinsing in TEGMA and 2-HEMA groups 2) no significant difference between TEGMA, 2-HEMA, and p-GM after priming 3) significant difference between control and priming only in p-GM group.
Because the impulses frequency decreased significantly when 2-HEMA, p-GM, and TEGMA solution were applied on the dentin cavity, it was thought that these primers had a clear desensitizing effect on the dentin perception.

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Tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine, regulates immune responses, inflammation, and programmed cell death (apoptosis), and is also a critical factor involved with rheumatoid arthritis (RA). To investigate the relationship between TNF-α-induced apoptosis and NF-κB activation in chondrocytic cells, we used human chondrogenic cells (USAC) isolated from a human osteosarcoma. In USAC cells, TNF-αinduced the phosphorylation and degradation of IκBα, resulting in the nuclear translocation of NF-κB. Further, the activation of NF-κB by TNF-αwas completely blocked by caffeic acid phenethyl ester (CAPE), which prevents the translocation of NF-κB to the nucleus. Inhibition of NF-κB activation by CAPE markedly enhanced TUNEL staining and reduced cell viability, as determined by an MTT method. These results suggest that the NF-κB signaling pathway negatively modulates TNF-α-induced apoptosis in chondrocytic cells

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While glucocorticoids are generally used for patients with articular rheumatism or joint diseases, significant side effects of these agents such as fractures due to osteonecrosis of the femur head or osteoporosis have been also reported. In the field of maxillofacial surgery, osteonecrosis of the temporomandibular condyle has been reported. We have established a cell line (USAC) which expresses chondrocytic and osteoblastic characteristics in vivo and in vitro. In this study, the effects of glucocorticoid (dexamethasone : DEX) on the proliferation and differentiation of USAC were examined.
DEX inhibited cell proliferation dose-dependently. At the status just before confluency, the synthesis of proteoglycan, collagen type II (Col II) and osteocalcin (OC), which are markers of chondrocytic and osteoblastic differentiation, was immediately enhanced by the addition of DEX. However, an increase in alkaline phosphatase activity, which implies the onset of calcification, was not shown by the addition of DEX. Interestingly, on days 3 and 7 of cultivation with DEX, expression of mRNA and protein synthesis of Col II and OC had decreased. Though DEX also enhanced the synthesis of Col II and OC in cells pretreated with BMP, the level of change was more dominant in OC than Col II.
These results indicate that DEX not only inhibits cell proliferation, but also modulates cell differentiation.

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The pontine nucleus locus coeruleus (LC) and subcoeruleus (SC) have been confirmed to be involved in descending modulation of nociceptive processing. Anatomically, the LC/SC provides bilateral noradrenergic innervation of the spinal cord. The present study was designed to demonstrate the existence of novel coeruleospinal neurons in which the axon projects to the contralateral dorsal horn of the spinal cord. Extracellular recordings were made from the dorsal horn with a carbon filament electrode (4-6MΩ). To block impulses from the LC/SC which descend through spinal pathways ipsilateral to the recording sites, a hemisection of the spinal cord ipsilateral to the recording sites was performed at the C2 level with fine forceps in all rats tested. In these rats, responses of dorsal horn neurons to noxious heat (53°C) applied to receptive fields were inhibited during either electrical (100, μ A, 100 Hz, 0.1 ms pulses) or chemical (L-glutamate, 50 nM. 1μ1, pH 6.8) stimulation of the LC/SC. Lesions of the LC/SC reversed LC/SC stimulation-produced inhibition. When yohimbine (1.0 mM), an antagonist of a₂, adrenocepters, was applied to the dorsal horn contralateral to the recording sites, LC/SC stimulation-produced inhibition was observed. Transection of the dorsolateral funiculus (DLF) contralateral to the recording sites did not affect LC/SC stimulation-produced inhibition. Following either transection of the ventrolateral funiculus (VLF) contralateral to the recording sites or injection of reversible local anesthetic (Lidocaine hydrochloride, 4%, 1 μ1) into the VLF contralateral to the recording sites, LC/SC stimulation failed to inhibit heat-evoked responses. These results suggest the existence of coeruleospinal neurons in which axons from the LC/SC descend through the VLF, but not through the DLF, ipsilateral side of the spinal cord and cross the midline at the spinal segment level to terminate in the dorsal horn on the side of the descending projection.

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The purpose of this study was clarify the acoustic characteristics of children of the Japanese consonants [s] and [∫], especially focused on the stage of missing deciduous incisors. The subjects 42 healthy children selected from the out patients and 7 males adults (control group).
And the children were divided into three groups by oral examination, Group A; with deciduous incisors fully erupted Group B; missing one or more deciduous incisors, and Group C; with all permanent incisors erupted.
The data speech waves of [s] [∫] uttered by 42 children and 7 males adults were analyzed with the cepstrum method. Analysis of the maximum frequency peaks was made for comparison among each groups. The results were as follows; The percentage with uncompleted speech [s] were more in Group A than in Group C. The average of maximum frequency peak for [s] of children groups showed high values in comparison with that of adult group. But there were no differences among the children groups. The maximum frequency peak data for [s] showed higher values than those for [∫]. The data of GroupB showed no difference from other children groups, so this result suggested that missing incisors has little influence upon the peak frequency of [s].

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Site where the swallowing sound is produced and acoustic characteristics of the swallowing sound in each site are unknown, although the swallowing sound is an important clue to diagnose acoustically dysphagia. Synchronized analyses of swallowing sound signals and VF images of swallowing events were done using new sound-image analyzing system to verify sites where the swallowing sounds are produced and acoustic characteristics of the swallowing sound in each site. Twelve healthy volunteers served as subjects. Ninety six swallows (8 swallows per each subject) were analyzed to measure bolus passing time, to identify bolus passing sound, to confirm the frequency of appeared passing sound, and to assess the maximum peak frequency.
Epiglottis passing time (121.7±92.4 msec) was the shortest, tongue base passing time (184.8±70.6 msec) was second, and upper esophageal sphincter (UES) passing time (342.9±61.1 msec) was the longest. Tongue base passing sound, epiglottis passing sound, initial UES passing sound, middle UES passing sound and final UES passing sound were identified. Frequency of epiglottis passing sound was the highest (94/96). Patterns of the appearance of passing sounds in each swallow were investigated. The appearance of four passing sounds (base of tongue passing sound, epiglottis passing sound, initial UES passing sound, and middle UES passing sound) in a swallow was the most dominant (22/96).
In assessing the averaged maximum peak frequency, initial UES passing sound (370.7±222.2 Hz) was the highest, middle UES passing sound (349.1±205.4 Hz) was second, tongue base passing sound (341.2±191.3 Hz) was third, v epiglottis passing sound (258.6 ± 208.2 Hz) forth, final UES passing sound (231.2±149.8 Hz) was fifth respectively. This study revealed site where the swallowing sound is produced and acoustic characteristics of the swallowing sound in each site.

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Computed Tomography (CT) is one of the diagnostic modalities utilized in diagnosing oral, maxillofacial disorders. The Showa University Dental Hospital installed a CT in 1990 and replaced it with a multi-detector CT (MDCT) in 2003. During the last 15 years, the number of maxillofacial disorder cases has increased, and around 1,200 cases per year have been referred to CT in the past five years. The reasons for referral include diagnosis and estimation of the extension of the malignancies in the oral region and the presurgical assessment of dental implant. In addition, cases of cellulitis/abscess induced by odontogenic infection were also referred for CT. The balance of the cost of CT and the payments made by the patients has resulted in profitability. In the future, although other modalities such as MRI and ultrasonography or volumetric CT using a cone-beam can be applied, CT may still play an important role in the management of patients at our dental hospital and some institutions referred to us.

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This report presents an adult orthodontic treatment with distal movement of molars using multi-bracket appliance. There are lots of restrictions for using the orthodontic appliances in the adult orthodontic treatment. Therefore, the adult orthodontic treatment contents often needs extraction, compared with the treatment in the term of growth. In this time, we obtained adult non-extraction case treated by distal movement of molars. The treatment results were as follows :
1. We were able to finish orthodontic treatment without causing labial tipping of upper incisors.
2. After treatment, facial esthetics is not so changed compared with first examination.
3. The slightly gingival recession and root resorption were appeared by orthodontic force.
We reported treatment procedures and results in this case and suggested some clinical considerations.

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This study was carried out to determine statistical information concerning the crowns and the fixed partial dentures (total number, type and rate of crowns, number of vital or non-vital abutment teeth, etc.) which were placed in the outpatients in the Department of Fixed Prosthodontics at Showa University Dental Hospital from April 2002 to March 2003. The following results were obtained :
(1) The total number of crowns and fixed partial dentures (FPDs) were produced 739; among them, crowns totaled 595 (80.5%) and FPDs, 144 (19.5%).
(2) Most of the crowns were full cast crowns (279, 46.9%); the second most commonly produced were resin-faced cast crowns (154, 25.9%); the third were porcelain-fused-to-metal crowns (151, 25.4%).
(3) Resin-faced cast crowns and porcelain-fused-to-metal crowns were most commonly used for the anterior teeth; full cast crowns and porcelain-fused-to-metal crowns, for the premolar teeth; full cast crowns, for the molar teeth.
(4) FPDs located in the posterior region were 82 (56.9%); the antero-posterior region were 38 (26.4%); the anterior region were 24 (16.7%).
(5) With regard to the relationship between the missing teeth and the abutment teeth of the FPDs, three-unit FPDs (one missing tooth with two abutment teeth) were most frequently treated in all regions.
(6) The crowns covered by the insurance dental service were 64.2%; the FPDs were 66.7%.
(7) Concerning the abutment teeth of the crowns, non-vital teeth were 87.7%, implant abutments were 6.7%; non-vital teeth of the FPDs were 78.6%; implant abutments were 0.8%.

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[in Japanese]

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