ウサギ脊髄虚血モデルにおけるミノサイクリンの神経保護作用の評価

OBJECTIVE: To investigate whether postischemic administration of minocycline attenuates hind-limb motor dysfunction and gray and white matter injuries after spinal cord ischemia. DESIGN: A prospective, randomized, laboratory investigation. SETTING: Laboratory in university, single institution. PARTICIPANTS: Male New Zealand White rabbits. INTERVENTION: Spinal cord ischemia was induced by an occlusion of the infrarenal aorta for 15 minutes. The groups were administered minocycline 1 hour after reperfusion (M-1; n = 8), minocycline 3 hours after reperfusion (M-3; n = 8), saline 1 hour after reperfusion (control [C]; n = 8), or saline and no occlusion (sham; n = 4). Minocycline was administered intravenously at 10 mg/kg 6 times at 12-hour intervals until 60 hours after the initial administration. MEASUREMENT AND MAIN RESULTS: Hind-limb motor function was assessed using the Tarlov score. For histologic assessments, gray and white matter injuries were evaluated 72 hours after reperfusion using the number of normal neurons and the percentage of areas of vacuolation, respectively. Motor function 72 hours after reperfusion was significantly better in group M-1 than in group C. The number of neurons in the anterior horn was significantly larger in group M-1 than in groups M-3 or C but did not differ significantly between groups M-3 and C. No significant difference was noted in the percentage of areas of vacuolation among the ischemia groups. CONCLUSIONS: Minocycline administration beginning at 1 hour after reperfusion improved hind-limb motor dysfunction and attenuated gray matter injury in a rabbit spinal cord ischemia model.博士（医学）・乙第1314号・平成25年5月29

Biomechanical effects of offset placement of dental implants in the edentulous posterior mandible

Background: Proper implant placement is very important for long-term implant stability. Recently, numerous biomechanical studies have been conducted to clarify the relationship between implant placement and peri-implant stress. The placement of multiple implants in the edentulous posterior mandible has been studied by geometric analysis, three-dimensional finite element analysis (FEA), model experimentation, etc. Offset placement is a technique that reduces peri-implant load. However, few studies have used multiple analyses to clarify the value of the offset placement under identical conditions.The present study aimed to clarify the biomechanical effects of offset placement on the peri-implant bone in edentulous posterior mandibles by comparative investigation using FEA and model experimentation with strain gauges.Methods: Three implants were embedded in an artificial mandible in the parts corresponding to the first premolar, the second premolar, and the first molar. A titanium superstructure was mounted to prepare models (experimental models). Three load points (buccal, central, and lingual) were established on the part of the superstructure corresponding to the first molar. Three types of experimental models, each with a different implant placement, were prepared. In one model, the implants were placed in a straight line; in the other two, the implants in the parts corresponding to the second premolar and the first molar were offset each by a 1-mm increment to the buccal or lingual side. Four strain gauges were applied to the peri-implant bone corresponding to the first molar.The experimental models were imaged by micro-computed tomography (CT), and FEA models were constructed from the CT data. A vertical load of 100 N was applied on the three load points in the experimental models and in the FEA models. The extent of compressed displacement and the strain in the peri-implant bone were compared between the experimental models and the FEA models Results: Both experimental and FEA models suffered the least compressed displacement during central loading in all placements. The greatest stress and compressive strain was on the load side in all types of placements.Conclusions: Offset placement may not necessarily be more biomechanically effective than straight placement in edentulous posterior mandibles.Keywords: Offset placement, Three-dimensional finite element analysis, FEA, Amount of compressed displacement, Stress distribution, Strain gaug

A biomechanical investigation of mandibular molar implants: reproducibility and validity of a finite element analysis model

Background: Three-dimensional finite element analysis (FEA) is effective in analyzing stress distributions around dental implants. However, FEA of living tissue involves many conditions, and the structures and behaviors are complex; thus, it is difficult to ensure the validity of the results. To verify reproducibility and validity, we embedded implants in experimental models and constructed FEA models; implant displacements were compared under various loading conditions. Methods: Implants were embedded in the molar regions of artificial mandibles to fabricate three experimental models. A titanium superstructure was fabricated and three loading points (buccal, central, and lingual) were placed on a first molar. A vertical load of 100 N was applied to each loading point and implant displacements were measured. Next, the experimental models were scanned on micro computed tomography (CT) and three-dimensional FEA software was used to construct two model types. A model where a contact condition was assumed for the implant and artificial mandible (a contact model) was constructed, as was a model where a fixation condition was assumed (a fixation model). The FEA models were analyzed under similar conditions as the experimental models; implant displacements under loading conditions were compared between the experimental and FEA models. Reproducibility of the models was assessed using the coefficient of variation (CV), and validity was assessed using a correlation coefficient.Results: The CV of implant displacement was 5–10% in the experimental and FEA models under loading conditions. Absolute values of implant displacement under loading were smaller in FEA models than the experimental model, but the displacement tendency at each loading site was similar. The correlation coefficient between the experimental and contact models for implant displacement under loading was 0.925 (p < 0.01). The CVs of equivalent stress values in the FEA models were 0.52–45.99%.Conclusions: Three-dimensional FEA models were reflective of experimental model displacements and produced highly valid results. Three-dimensional FEA is effective for investigating the behavioral tendencies of implants under loading conditions. However, the validity of the absolute values was low and the reproducibility of the equivalent stresses was inferior; thus, the results should be interpreted with caution

Gastrointestinal Stromal Tumor in a Patient with Neurofibromatosis: Abscess Formation in the Tumor Leading to Bacteremia and Seizure

A 66-year-old woman with neurofibromatosis type 1 (NF1) was brought to the emergency room with seizures and high-grade fever. Seizure in adult NF1 patients raises concern for intracranial lesions. However, neurological examination and central nervous system imaging failed to detect any causative intracranial lesions for her seizure. Gram-positive cocci, Streptococcus anginosus, were detected by blood cultures. Abdominal computed tomography revealed a well-defined round mass 7 cm in diameter, which was found to be a small intestinal gastrointestinal stromal tumor (GIST) containing an abscess. There was fistula formation between the intestinal lumen and the abscess, in which there were numerous Gram-positive cocci. The seizure may have been caused by hypoosmolality (hyponatremia and hypoproteinemia), which may result from decreased food intake associated with high-grade fever and general malaise. In this case GIST originating from the small intestine was invaded by S. anginosus through a fistula, leading to abscess formation, bacteremia, high-grade fever, and seizure, which was the first clinical manifestation

Novel Removable Keeper System for Magnetic Attachments on Overdenture Abutments

Magnetic attachments are being increasingly used for removable dental prostheses, mainly because they are relatively simpler to use than other attachments, and they show good retention and stability. However, this approach poses some problems. In patients undergoing magnetic resonance imaging (MRI) procedures, the presence of magnetic structures and keepers may cause artifacts that hinder the diagnosis. We therefore aimed to develop a technique that could reduce the damage caused to dental roots and root caps during removal of the magnetic keepers. A modified keeper tray and custom-made metallic guide bar were used for root cap fabrication. The retrieval hole of the root caps was made from the bottom of the keeper tray to the labial side of the root. A special crown remover was then inserted into the retrieval hole and rotated to facilitate removal of the magnetic keepers through the hole without causing damage to the root caps. Conclusion: This study describes a new technique that uses a keeper tray along with magnetic attachments for overdentures to enable simple removal of the keeper without causing damage

Improving the efficiency of complete denture treatment

In Japan, the number of elderly people with missing teeth has been decreasing. However, the number of patients wearing complete denture has not decreased. Therefore, suitable complete denture adjustment for the elderly people is important. The chair time and treatment contents (medical interview, medical examination, fitting, occlusion, adjustment, denture cleaning, patient’s instruction, polishing, postoperative instruction, denture score, blank time) involved in complete denture adjustment were investigated and it is confirmed that there was a lot of patient’s and blank time. The blank time is defined as “time not engaged in treatment” for the dentist, “observation time” for the assistant, and “time sitting in the chair doing nothing” for the patient. This research aimed to clarify a treatment procedure that allows for effective use of the blank time to provide appropriate treatment to each patient. The participants included 31 patients with complete dentures, 14 dentists, and 12 less experienced dentists. Treatment timetables were created using video data. Analyses were carried out to develop a more effective treatment protocol by changing treatment procedures and contents. Issues associated with treatment were also investigated. Treatment activities and chair time during denture adjustment (57 participants) were investigated to do treatment smoothly. As a result there were 22 out of 31 patients (deficiency of the denture cleaning etc.) whose treatment activities should be improved. The results suggested that treatment procedures that allow for effective use of patient’s and less experienced dentist’s blank time to provide appreciate treatment to each patient can be clarified

Factors determining maximum torque and achievement of the recommended torque for manual implant drivers: A pilot study

When fixing an oral implant superstructure with a screw, operators must be aware of the torque being applied by their fingers to prevent the transmission of excessive or insufficient torque to the implant. In this study, we identified the factors that determine individual maximum attainable torque and those that determine the achievement of the prescribed torque. We evaluated 16 dentists on their use of two types of manual implant drivers（UniGrip by Nobel Biocare and Carrier Hex by Zimmer Biomet）and measured the maximum torque（MT）generated by their fingers. The target torque was set at 15N. Measurements were taken while the participants were turning the implant screw with or without gloves in both clockwise and counterclockwise directions. The grip and finger strength of each participant were measured, and the data showed that torque values were higher among the male participants during clockwise rotation and when they were wearing gloves（p＜0.05）. Positive correlations were found between the MT and grip strength and between the MT and finger strength. These results suggest that dentists should monitor their ability to consistently achieve the recommended torque for implant drivers

The Effect of Viscosity of Oral Moisturizers and Residual Ridge Form on the Retention Force of Maxillary Complete Dentures

Aim: To study the effects of viscosity of oral moisturizers and residual ridge form on theretention force of maxillary complete dentures.Methods: Thirty-five maxillary edentulous participants were recruited. Three types of oralmoisturizers with different viscosities, artificial saliva, and denture adhesive were used. Thesewere applied between the intaglio surface of the denture and basal seat mucosa. The centralincisor was loaded 45° upward to the occlusal plane. The force needed to dislodge the denturewas measured using a digital force gauge. Dental impressions of the polished surfaces andintaglio surfaces of the maxillary complete dentures were obtained. Then, duplicate dentureswere cast using auto polymerizing acrylic resin. The buccolingual molar residual ridge form wasassessed using the dental impressions. The duplicate denture was used to measure the positionalrelationship of the central incisor edge, anterior residual ridge crest, and posterior border ofdentures. The effect of residual ridge form on retention force was analyzed.Results: The gel-type oral moisturizer showed significantly greater retention than theother types (P < .05). The retention force and buccolingual molar residual ridge form were notcorrelated. As the ratio of the distance from the central incisor to the anterior residual ridgecrest and the distance from the anterior residual ridge crest to the posterior denture borderincreased, retention force decreased (r = -0.352; P < .01).Conclusion: The results indicate that the retention force of dentures is affected by oralmoisturizer viscosity and the relative position of the anterior residual ridge crest

Kansai University Library 100th anniversary

目次 【序文】記念誌の刊行にあたって（図書館長　内田慶市）図書館創設100周年によせて（学長　楠見晴重）記念誌の編集について【第1部　この20年を振り返って】高槻図書室開館（広瀬雅子）…3阪神・淡路大震災（高橋真澄）…8図書館システムの変遷（徳岡久実・濱生快彦）…12図書館ビジョン7項目の制定（濱生快彦）…20図書館におけるアウトソーシング（高橋真澄）…26電子展示（濱生快彦）…36市民利用開始（広瀬雅子）…41図書館ウェブサイト（濱生快彦）…442010プロジェクトによる新図書館（高橋真澄・田中恵美）…48図書館リニューアル工事（新谷大二郎）…60図書館の現在と未来（堀口和弘）…68【第2部　図書館に想う】関西大学図書館創設100周年に寄せて（市川訓敏）…79図書館の思い出、図書館への思い（北川勝彦）…85図書館在職時の思い出（柴田真一）…91数々の貴重書（田中登）…95関西大学図書館100周年にあたって : 私の夢想する図書館（内田慶市）…100【第3部　図書館の文庫・コレクション】文庫・コレクションの紹介（鵜飼香織）…111【第4部　資料編】図書館年譜（明治19.3 ～平成26.7）…119サービスに係る統計（総合図書館）…146サービスに係る統計（高槻図書室・ミューズ大学図書館・堺キャンパス図書館）…148蔵書数の推移…149図書費執行額の推移…150展示一覧…152他大学図書館との協定一覧…160【「図書館コラム」】新人時代の思い出（高松和美）…11エレベーターにまつわる話（吉田有輝）…19泣き別れたり、親子になったり（嶋田有理香）…35貴重なのは本だけ？貴重書担当のつぶやき（大上良樹）…40会長校のころ（金東瀅）…46『コアラ博士』にまつわるあれこれ（松本和剛）…57広報誌『KULione 』誕生秘話（白髪友賀）…59本と夢を運んだテレリフト（芝谷秀司）…66LOUIS VUITTON（加藤博之）…7