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11.
12.
Shimoyama T Horie N Kato T Nasu D Kaneko T 《The Journal of clinical pediatric dentistry》2003,27(2):177-180
A case of Tourette's syndrome is presented in a thirteen-year-old boy with obsessive-compulsive symptoms including self-mutilation of the upper lip. His upper lip injury was caused by complication of picking with fingernail, and self-biting with the lower anterior teeth. It became rapidly worse and the median part of the upper lip collapsed. But the placement of an acrylic splint was able to prevent further damage of the upper lip. 相似文献
13.
Effect of iron on inhibition of acid demineralisation of bovine dental enamel in vitro 总被引:1,自引:0,他引:1
Buzalaf MA de Moraes Italiani F Kato MT Martinhon CC Magalhães AC 《Archives of oral biology》2006,51(10):844-848
OBJECTIVES: Iron ions (Fe(2+)) have been shown to be cariostatic in many studies particularly by their ability to reduce bacterial metabolism. Nevertheless, the role of iron ions on dissolution of enamel is unexplored. The aim of the present study was therefore to investigate the protective effect of increasing concentrations (0-120mmol/L) of Fe(2+) on the dissolution of enamel. DESIGN: Enamel powder was subjected to acetic acid made with increasing concentrations with respect to FeSO(4)x7H(2)O. In order to determine the amount of enamel dissolved, the phosphate released in the medium was analysed spectrophotometrically using the Fiske-Subarrow method. Data were tested using Kruskall-Wall and Dunn's tests (p<0.05). The degree of protection was found to approach maximum at about 15mmol/L Fe(2+). Higher concentrations of Fe(2+) did not have an extra effect on inhibition of dissolution of enamel powder. In the next step, the protective effect of 15mmol/L Fe(2+) against mineral dissolution of the bovine enamel was evaluated using a simple abiotic model system. Enamel blocks were exposed to a sequence of seven plastic vials, each containing 1mL of 10mmol/L acetic acid. The acid in vial 4 was made 15mmol/L with respect to FeSO(4)x7H(2)O. The mineral dissolved during each challenge was thus determined by phosphate released as described above. Data were tested using two-way ANOVA (p<0.05). RESULTS: Lower demineralisation (around 45%) was found in vial 4 (with Fe) that continued stable until vial 7. CONCLUSIONS: Thus, our data suggest that Fe(2+) can be effective on inhibition of dissolution of enamel and that this effect may be durable. 相似文献
14.
Kato T Akiyama S Kato Y Yamashita S Masuda Y Morimoto T 《Journal of orofacial pain》2006,20(4):317-324
AIMS: To assess the occurrence and the modality of spontaneous orofacial behaviors of awake healthy subjects without pain who were unaware of bruxism during wakefulness. METHODS: Sixteen asymptomatic subjects read silently for 30 minutes while polygraphic recordings, including electromyographic (EMG) activity from masticatory and leg muscles, chest respiratory movements, and the movements and sounds of larynx, were made with simultaneous audio-video monitoring. Orofacial behaviors were scored based on the polygraphic and audio-video records. The activity and duration of masseter EMG bursts were calculated for the types of orofacial behaviors. RESULTS: The number of orofacial behaviors varied between subjects; swallowing was most frequently observed. Approximately half of the orofacial behaviors occurred closely with body movements. Of all masseter EMG bursts detected, 55% were associated with functional orofacial behaviors, while 45% were regarded as nonfunctional. More than 80% of these masseter bursts lasted for less than 2 seconds, with an activity less than 20% of maximal voluntary clenching. These values did not differ between the types of associated orofacial behaviors. CONCLUSION: Although the occurrence of spontaneous orofacial motor activity is variable, asymptomatic subjects can exhibit substantial masseter bursts during wakefulness that are not associated with functional orofacial behaviors. The use of physiological and audio-video records permits spontaneous orofacial behaviors to be specifically identified, thereby allowing nonfunctional masseter EMG activity to be differentiated from functional masseter EMG activity. 相似文献
15.
Kogawa EM Kato MT Santos CN Conti PC 《Journal of applied oral science : revista FOB》2005,13(3):280-285
16.
Horie N Kawano R Inaba J Numa T Kato T Nasu D Kaneko T Kudo I Shimoyama T 《Journal of Oral Science》2008,50(1):33-36
Angina bullosa hemorrhagica (ABH) is an oral mucosal blood blister that develops without blood dyscrasia or vesiculobullous disorder. Although a minor mucosal trauma has been suggested as a triggering factor for ABH, its etiopathogenesis, especially the causative role of systemic conditions, is largely unknown. We investigated the presence or absence of local factors as well as systemic background disease in 16 patients with ABH arising in the soft palate. All the lesions were solitary, and 75% of them (n = 12) appeared during the ingestion of hard or crispy food. With regard to underlying systemic conditions, hypertension was the most common (n = 6), and asthma, insomnia, diabetes mellitus, rheumatoid arthritis, gastrointestinal disorder and hyperuricemia were also recorded (n = 1 each). Five patients had no significant background disease. There were no recalcitrant or recurrent cases. In conclusion, the present study has revealed that scratching of the oral mucosa during eating plays an important role in the formation of ABH. Hypertension appears to be the most frequent background condition, but its pathogenic relationship with ABH remains speculative, as hypertension is fairly common in adults. 相似文献
17.
18.
Takemura A Nakagawa I Kawai S Inaba H Kato T Hamada S Amano A 《Journal of periodontology》2006,77(5):883-890
BACKGROUND: Tumor necrosis factor-alpha (TNF-alpha) is associated with chronic gingival inflammation and is suspected to influence periodontal destruction. However, the exact roles of TNF-alpha in wound healing and periodontal tissue regeneration are largely unknown. In the present study, we examined the effects of TNF-alpha on migration and proliferation of human periodontal ligament (PDL) cells. METHODS: PDL cells were cultured in the presence of TNF-alpha to determine its effects on cellular migration and proliferation. The protein expression profiles of alpha5 and beta1 integrin subunits and their related molecules, paxillin and focal adhesion kinases (FAK), were investigated. Gene expression of fibronectin also was assayed. Further, the activation of Rho-family small guanosine triphosphate (GTP)-binding protein (RhoA) was evaluated using a GTP-loading pull-down assay, and focal adhesion formation by PDL cells after transfection with the expression vector of paxillin-fused green fluorescent protein (GFP) also was observed with confocal microscopy. RESULTS: Cellular migration was impaired by TNF-alpha and recovered following the addition of anti-TNF-alpha antibodies. In contrast, PDL cell proliferation was not affected by TNF-alpha. TNF-alpha upregulated the expression of the alpha5 and beta1 integrin subunits, whereas fibronectin was not overexpressed. Phosphorylation of paxillin and FAK by PDL cells was induced, and RhoA activation also was induced. Confocal microscopic analysis revealed that TNF-alpha induced focal adhesion and stress fiber formation in all parts of the cells. CONCLUSION: Our results suggested that TNF-alpha impairs cellular migration by enhancing cellular adhesive ability following significant focal adhesion and stress fiber formation. 相似文献
19.
Yoshinori?AraiEmail author Ayuta?Yamada Tadashi?Ninomiya Takafumi?Kato Yuji?Masuda 《Oral Radiology》2005,21(1):14-18
Objectives The aim of this paper is to report a newly developed micro-computed tomography system for in vivo use.Methods The system was composed of a micro-focus X-ray tube and an image intensifier (I.I.), both of which rotated around the object stage. A guinea pig and a rat were examined. The anesthetized animal was set on the secure object stage. Images of the head of the guinea pig and the tibia/knee joint of the rat were taken. In addition, an image of the rat’s tail was taken. The reconstruction and the image viewing were carried out using I-View software.Results The voxel matrix was 512 × 512 × 384. The voxel sizes ranged from 10 × 10 × 10 µm to 100 × 100 × 100 µm. The exposure time was 17 s, and the reconstruction time was 150 s. The head of the guinea pig and the tibia/knee joint of the rat were observed clearly under 100-µm and 30-µm voxels, respectively. The trabecular bone of the tail was also observed clearly under a 10-µm voxel.Conclusions The newly developed micro-computed tomography system makes it possible to obtain images of anesthetized animals set on a secure object stage. Clear bone images of the small animals could be obtained within a short time. 相似文献
20.
A comparison of the relative efficacies of four hand and rotary instrumentation techniques during endodontic retreatment 总被引:1,自引:0,他引:1
Imura N Kato AS Hata GI Uemura M Toda T Weine F 《International endodontic journal》2000,33(4):361-366
AIM: The purpose of this study was to quantify the amount of remaining gutta-percha/scaler on the walls of root canals when two engine-driven instruments (Quantec and ProFile) and two hand instruments (K-file and Hedstr?m file) were used to remove these materials. The amount of apically extruded debris and the time required for treatment were also recorded. METHODOLOGY: One hundred extracted mandibular premolars were prepared using a modified step-back, flare technique and obturated with the lateral condensation technique. After repreparation with the test instruments, the specimens were cut transversally at the cervical, middle and apical thirds with steel discs and the three sections were split longitudinally. The amount of residual debris on the canal walls in each section was examined using a stereomicroscope. RESULTS: In all groups the cervical and middle thirds showed no debris. In the apical third, obturating material was observed in some specimens. No statistically significant difference was found between the two groups for incidence of debris, although the Hedstr?m group showed a greater number of samples with remaining gutta-percha/sealer. When analysing dirty specimens only, there was a statistically significant difference between the four groups (P < 0.01) with the Hedstr?m group having significantly less length of canal wall with remaining obturation material than the Quantec group. There was no significant difference amongst the groups for weight of extruded debris. However, there was a significant difference amongst the groups for mean treatment time with the Hedstr?m file group requiring significantly less time than the Quantec group (P < 0.001); no significant differences were found between the other groups. Six instruments fractured in the Quantec group, four in the ProFile group, two in the Hedstr?m group and two in the K-type group. CONCLUSIONS: The results showed that overall, all instruments may leave filling material inside the root canal. During retreatment there is a risk of instrument breakage, especially rotary instruments. 相似文献