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松本歯科大学第2学年学生の学業成績の変化と学習観・学習方略 : 07年度から10年度までの第2学年学生を対象として
Get PDFapplication/pdfAs a countermeasure against "cram education" in the 1970s and 1980s, the Japanese education ministry published new educational guidelines in 1998. It called for promoting children's ability to study and think with autonomy, but due to a significant reduction in educational content and the number of classes, it was dubbed the "relaxed education policy." Several years later, those children graduated from high school and became applicants to institutions of higher education. It has been said that their academic ability is low and they are not motivated to study. Additionally, the sharp decline in the college-age population and the decreasing number of applicants have become serious issues. This study analyzed the current student situation from various perspectives. The subjects consisted of 365 students who were in the 2nd year of university studies each year between 2007 and 2010. At first, we explored the academic performance of the students. We investigated whether or not there was a year to year difference in student performance. Students who were in the 2nd year in 2007 were compared to students who were in the 2nd year in 2010. Differences among each annual group were considered significant. Secondly, we investigated the relationship between academic performance and students' concepts of learning or strategies. Two kinds of psychological scales , "Students' Beliefs about Learning" (Ichikawa, 1998) and Learning Strategy (Ueki, 2002), were used. The student group with a high score group for Seeking Meaning showed significantly higher academic performance than the group with a low score in that area. The group with a high score for Elaborative Strategy also showed a significantly higher academic performance. These findings show that some specific and appropriate actions should be taken to improve the academic situation. For instructors, it is useful to take the students' concepts of learning into account when we teach them.journal articl
衝撃荷重によるチタンインプラントの疲労破壊
Get PDFapplication/pdfチタンおよびチタン合金は,骨とオッセオインテグレーションすることや,機械的性質および加工性に優れるなどの理画から,現在のインプラント製品の主流となっている.しかしながら臨床において,チタンおよびチタン合金製のインプラントが破折する症例が認められている.インプラント治療後のトラブル症例の中でも破折は少なく,その割合はフィクスチャーが1%であり,アバットメントスクリューが2%であるが,歯科治療におけるインプラントの需要は年々増加する傾向にあり,破折に対する検討は早急に行う必要があると考えられる.臨床でのインプラントの破折は,ブラキシズムや補綴形態の不備によるオーバーロード,それに伴う骨吸収,さらにインプラントの構造上の問題などが原因とされており,これらが複雑に関与して発生する.したがって,破折の原因を究明することは困難であるが,破折のほとんどは,破壊強度よりも低い応力の繰り返し負荷によって生じる疲労破壊とされている.疲労試験は,一般的に静的荷重を負荷する装置を使用した試験方法で評価される.しかしながら,口腔内の咬合状態はさまざまであり,ブラキシズムを有する患者の咬合力は正常者よりも4～7倍も大きくなると報告されている.またインプラントは歯根膜を有している天然歯と比較すると,咬合時により大きな衝撃荷重が発生するとされている.このことからも,インプラントの破折原因を究明する際に静的荷重のみならず,実際の咬合状態を考慮した疲労試験を行い,検討する必要があると考えられる.そこで本研究はインプラント用疲労試験機を用いて,衝撃荷重によるチタンインプラントの疲労破壊について検討を行った.材料にはJIS第2種純チタンの棒材を使用して,フィクスチャーとアバットメントからなる2ピースタイプインプラントを切削加工にて作製し,実験に用いた.実験はインプラントの強度試験,疲労試験,破断面の観察,CT撮影による破折状態の観察および画像解析,さらに金属組織の観察を行い,インプラントの疲労破壊について検討した.その結果,以下の結論が得られた.1.インプラントが破折するまでの回数は,衝撃荷重が小さくなるに従い多くなった.また植立方向30°は45°と比較して,破折するまでの回数は多くなり,試験速度1Hzは2Hzよりも多くなった.2.疲労破壊したインプラントの破断面には,ストライエーションと亀裂が認められた.一方,破折までの回数が少なく,疲労による破壊ではないと考えられた破断面は延性破壊像であった.3.疲労試験後のインプラントの破折状態は5種類に分類され,破折するまでの回数が多くなるに従い,Type 0(疲労破折していない)→Type 1(アバットメント上部より破折)→Type 2(フィクスチャーより破折し,アバットメント上部も破折)→Type 3(フィクスチャーより破折)→Type 4(フィクスチャーより破折し,破折線直下のアバットメントも破折)となる傾向を示した.4.疲労破壊したインプラントの金属組織には,双晶や亀裂が認められた.5.衝撃荷重を用いた疲労試験は,臨床におけるインプラントの破折原因の究明に有益であることが示唆された.journal articl
Preventive Effects of a Kampo Medicine, Hangeshashinto on Inflammatory Responses in ipopolysaccharide-Treated Human Gingival Fibroblasts
Get PDFapplication/pdfIn the present study, we investigated the effects of a Kampo medicine hangeshashinto (TJ-14) on the production of prostaglandin E2 (PGE2), interleukin (IL)-6 and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS) from Porphyromonas gingivalis. HGFs proliferation was dose-dependently decreased with hangeshashinto at days 3 and 7. However, treatment with LPS (10 ng/ml), hangeshashinto (up to 1 mg/ml) and their combinations for 24 h did not affect the viability of HGFs. Hangeshashinto dose-dependently suppressed LPS-induced PGE2 production but did not alter basal PGE2 level. Hangeshashinto weakly decreased LPS-induced IL-6 and IL-8 productions. Hangeshashinto decreased cyclooxygenase (COX)-1 and COX-2 activities to approximately 60% at 1 mg/ml. Hangeshashinto decreased cytoplasmic phospholipase A2 (cPLA2) expression and LPS-induced COX-2 expression but not affected annexin1 expression. Hangeshashinto weakly suppressed LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation, which is known to lead to ERK activation and cPLA2 phosphorylation. These results suggest that hangeshashinto decreased PGE2 production by (1) suppression of cPLA2 and LPS-induced COX-2 expression, and to a lesser extent, (2) inhibition of COX-2 activity and (3) inhibition of cPLA2 phosphorylation and its activation via inhibition of ERK phosphorylation. Moreover, it is also suggested that hangeshashinto may be useful to improve gingival inflammation in periodontal disease.journal articl
Preventive effects of a kampo medicine, orento on inflammatory responses in lipopolysaccharide treated human gingival fibroblasts
Get PDFapplication/pdfIn the present study, we investigated the effects of a Kampo medicine Orento (TJ-120) on the production of prostaglandin E2 (PGE2), interleukin (IL)-6 and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide from Porphyromonas gingivalis (PgLPS). HGFs proliferation was dose-dependently decreased with Orento at days 3 and 7. However, treatment with PgLPS (10 ng/ml), Orento (up to 1 mg/ml) and their combinations for 24 h did not affect the viability of HGFs. Orento suppressed PgLPS-induced PGE2 production in a
dose-dependent manner but did not alter basal PGE2 level. In contrast, Orento did not alter PgLPS-induced IL-6 and IL-8 productions. These alterations by Orento were similar to those by a mitogen-activated protein kinase kinase (MAPKK/MEK) inhibitor, PD98059. A Orento showed no effect on cyclooxygenase (COX)-1 and COX-2 activities, and increased cytoplasmic phospholipase A2 (cPLA2) expression and increased PgLPS-induced COX-2 expression. Orento suppressed PgLPS-induced mobility retardation of cPLA2 band on sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) gels, that is cPLA2 phosphorylation and its activation, while Orento alone did not alter cPLA2 phosphorylation. Orento suppressed PgLPS-induced extracellular signal-regulated kinase (ERK) phosphorylation, which is known to lead to ERK activation and cPLA2 phosphorylation. These results suggest that Orento decreased PGE2 production by inhibition of cPLA2 phosphorylation and its activation via inhibition of ERK phosphorylation, and also that Orento may be useful to improve gingival inflammation in periodontal disease.journal articl
口腔粘膜病変における液状化細胞診の検討
Get PDFapplication/pdfThe aim of this study was to evaluate the utility of liquid-based cytology (LBC) for diagnosis of oral mucosal lesions, compared with the conventional smear cytology. Specimens were taken from the same patient by the both conventional and LBC preparation methods. Samples were stained with papanicolaou and PAS stainings according to standard methods. RNA and protein were isolated from LBC samples. The cytological features of LBC samples showed similar quality to those of conventional ones. In addition, RNA and protein could be detected from LBC samples. In conclusion, LBC specimens are useful not only for cytological diagnosis but also for gene and protein analyses in oral lesions.journal articl
下顎歯肉と食道に発生した同時性重複癌の1例
Get PDFapplication/pdfA case of synchronous double cancers of the lower gingival and esophagus in a 60-year-old man is presented. The patient's history, such as heavy smoking, overconsumption of alcohol suggested that he might have a high risk of synchronous double primary cancers. The lower gingival carcinoma was histologically diagnosed as squamous cell carcinoma and successfully treated with segmental mandibulectomy, radical neck dissection and reconstruction using free radial forearm flap. Gastrointestinal fiberscopy (GIF) was performed before treatment of the lower gingival cancer revealed esophageal superficial cancer. After the resection of lower gingival cancer and reconstruction, we conducted swallowing rehabilitation by the balloon method to widen the esophageal tract. Three months after completion of treatment for the lower gingival cancer, endoscopic submucosal dissection (ESD) for large superficial cancer of the esophagus was performed. It is was considered that examination of the upper gastrointestinal tract in the patients with oral and maxillofacial cancer by GIF and the postoperative swallowing rehabilitation were important for double primary cancers.journal articl