日本レーザー歯学会誌
Online ISSN : 2185-6702
Print ISSN : 0917-7450
ISSN-L : 0917-7450
10 巻, 1 号
選択された号の論文の11件中1~11を表示しています
  • 斉藤 茂, 倉林 仁美, 山崎 健一, 柴崎 好伸
    1999 年 10 巻 1 号 p. 2-8
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    The objectives of the present study were to evaluate the effects of soft laser irradiation for the proliferation and the differentiation of human bone cells and periodontal cells cultured on titanium plates and plastic dishes both derived from the identical donor.
    Bone cells derived from mandibular fragments and periodontal ligament (PDL) cells from mandibular first premolars were obtained simultaneously from the identical orthognathic patient. Both cells in the 6th passage were seeded (5×103 cells/well) in 24-well plastic culture dishes with or without titanium plates and incubation continued for 72 hours. During the incubation period, soft laser irradiation was performed none, once, twice, which were served as control, 1×laser, 2×laser, respectively. At the end of incubation period, both cells were used for the assays of DNA synthesis and alkaline phosphatase (ALP) activity. The following results were obtained:
    1. Bone cells cultured on plastic dishes did not show any significant change of DNA contents and ALP activity by the various time periods of soft laser irradiation. On the other hand, bone cells cultured on titanium plates showed significant increases of DNA contents and ALP activity by the soft laser irradiation, especially by 1×10 minutes laser irradiation group. In this group, the level of DNA contents and ALP activity by titanium-cultured-bone cells were significantly greater than those by plastic-cultured-bone cells.
    2. In case of PDL cells, the level of DNA contents and ALP activity were constant for any kind of groups with the exception of 2×10 minutes laser group which showed significant DNA increase as compared to control group, suggesting that the existance of titanium plates and/or the irradiation of soft laser were not effective for cultured PDL cells.
    These results suggest that the proliferation and the differentiation of bone cells cultured on titanium plates can be stimulated by the irradiation of soft laser in vitro.
  • 善入 邦男, 井上 昌孝, 吉川 一志, 白石 充, 井上 正義, 熊崎 護
    1999 年 10 巻 1 号 p. 9-14
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    Er: YAGレーザーを, エナメル小柱あるいは象牙細管の走行に対して平行および直角に照射し, 照射面の形態学的特徴と照射方向との関連性について検討した. 大阪歯科大学歯科保存学講座および口腔外科学講座にて採取した新鮮抜去臼歯を, 歯科用ディスクによって注水下で近遠心的に2分割し, 耐水ペーパー (#600番) で研磨仕上げを行った. Er: YAGレーザー機器としてはアーウィン (モリタ社・ホヤ社製) を用いた. 照射方向は, エナメル小柱あるいは象牙細管の走行に対して平行 (平行照射), および直角 (直角照射) とした. 照射条件は, 180mJ, 1ppsとし, エナメル質においては2秒間, 象牙質においては1秒の照射とした. レーザー照射したエナメル質面・象牙質面, および照射による切削片を通法によって金蒸着し, SEM観察した. エナメル質への直角照射においては花咲き状の像が観察され, 平行照射ではロッド状の像が認められた. 切削片は, 平行照射の方が垂直照射に比べて大きかった. この理由は, エナメル小柱および小柱間質よりも小柱鞘の方が水分含有量が多いため, 水に対する吸収率が高いEr: YAGレーザーの照射によって小柱鞘が選択的に破壊され, 直 角照射よりも平行照射の場合が, 破壊が大きくなったものと考えられた. 一方, 象牙質面においては, 照射方向の違いによる形態学的特徴の差はあまり見られなかった. これは, エナメル質に比べて象牙質の水の含有量が十数倍多いため, 照射方向による切削の異なりに差が現われなかったものと考えられた.
  • 櫻庭 栄一, 小林 一行, 野村 典生, 山本 章代, 山口 博康, 中村 治郎, 新井 高
    1999 年 10 巻 1 号 p. 15-24
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    The purpose of this study was to research the relation between different energy patterns on the same output power and wound healing by the pulsed Nd: YAG laser irradiation. Five hairless rats were used on this study. The pulsed Nd: YAG laser was irradiated with different energy patterns on the same output power (Group 1: 60 mJ, 100 pps. Group 2: 100 mJ, 60 pps. Group 3: 200 mJ, 30 pps. ; 6 W) in a duration 5 sec. in dorsal skin of rats. Wound healing process after the pulsed Nd: YAG laser irradiation were evaluated over a period of 28 days by clinical photographs and histological observation. In the early period of wound healing (0, 1, 3 days after the laser irradiation), wound size of Group 1 was narrow compared with Group 2 and 3 by clinical photographs and histological observation. Until 14 days of healing, a difference was found between the Group 1 and the other groups. In Group 2 and 3 of laser irradiation, a delay in wound healing was observed. After 21 days of healing, an extensive reduction of the wound size in each groups was observed. This report showed, even if the laser is irradiated on the dorsal skin at the same output power, the irradiated tissues receive a severe damage and a delay in wound healing would be observed in the high energy irradiation.
  • 海老原 新, 高品 正明, 竹田 淳志, 須田 英明
    1999 年 10 巻 1 号 p. 25-33
    発行日: 1999/06/01
    公開日: 2011/06/02
    ジャーナル フリー
    The aim of this study was to investigate Nd: YAG laser's capability of removing canal obstructions.
    Twenty four extracted single-human teeth were used in this experiment. After removing the tooth crown, they were randomly divided into three groups: dowel core, gutta-percha, and file removal groups. In the dowel core and gutta-percha removal groups, root canals were cleaned, shaped and obturated with laterally condensed gutta-percha and sealer. Then, in the dowel core removal group, post spaces 7.5 mm in length were created, and dowel cores were placed with glass ionomer cement. The dowel cores were made from an Au-Ag-Paalloy. In the file removal group, a tip of a K file, 3 mm long, was intentionally fractured between the middle and apical third of the root canal.
    Nd: YAG laser (output energy: 900mJ 10pps) irradiation with an optical fiber (∅=400μm) vwas performed in water to remove dowel cores, gutta-percha and K files from the root canal, and the laser irradiation time was counted. In addition, contact-micro-radiographs were taken before and after the laser irradiation, and the rate of postoperative increase in the root canal area was evaluated.
    The results were as follows:
    1. Nd: YAG laser was able to remove dowel cores and gutta-percha from the root canal. In 5 out of 8 cases, files were successfully removed from the root canal in the file removal group.
    2. The irradiation time of Nd: YAG laser in the dowel core, gutta-percha, and file removal groups was, 670 (±345), 19 (±8), and 317 (±220) sec, respectively.
    3. The rate of postoperative increase in the canal area of the dowel core, gutta-percha, and file removal groups was, 28, 6, and 62%, respectively.
  • 山田 一郎, 橋本 賢二, 村井 睦彦, 田中 秀生, 増本 一真, 山口 万枝, 式守 道夫, 福田 廣志
    1999 年 10 巻 1 号 p. 34-38
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    We have developed the fluorescence diagnostic apparatus of oral lesion. In this study, we analyzed autofluorescence of SCC and leukoplakia. Both cases of SCC and leuk oplakia, we found two fluorescence peaks. In case of SCC, a major peak was at 628 nm and a smaller peak was at 668 nm. As regard to intensity, the maximal intensity of SCC was 18 times stronger than that of normal oral mucosa. In case of leukoplakia, a major peak was at 658 nm and smaller peak was at 627 nm. The maximal intensity of leukoplakia was five times stronger than that of normal oral mucosa. The results suggested that the autofluorescence diagnosis of oral lesion would be possible by new fluorescence diagnostic apparatus.
  • 上田 吉生, 山田 一郎, 小松 寿子, 橋本 賢二, 時田 康弘, 杉本 正人
    1999 年 10 巻 1 号 p. 39-45
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    We developed the new colorimetric analysis system with the KOITO white light laser. The KOITO white light laser is a hollow cathode He-Cd laser device that simultane ously oscillates three light laser beams of three primary colors (red, green, blue) from a single laser tube. These beams are formed into a white light laser. In addition, because the oscillation wavelengths of red (635.5 nm, 636 nm), green (533.7 nm, 537.8 nm), blue (441.6 nm) color light are very near the ideal three primary colors.
    This system has three character. First character is non-contact type without integral sphere. Second is using pen-type probe which contain the bundle type fiber. Third is recording the rate to three colors in the standard reflex light.
    We examined the efficacy of this colorimetric analysis system with experimental study and clinical cases. On the other hand, we improved this system in the diagnosis of oral malignant tumor.
    Using this system, we could measure the color disorders in the oral cavity non-invasively, easily, immediately, exactly. Moreover we performed spectral analysis in patients with an oral squamous cell carcinoma. We found that there were bimodal peak at 650 and 690 nm at the excitation wavelength of 441.6 nm and that this result is different from the normal autofluorescenc.
    We consider that this coloriometric analysis system is useful to measure the color disorders in the oral cavity and has possibility to be improved in the diagnosis of oral malignant tumor.
  • 岩田 健男, 清水 光, 田口 直幸, 草刈 玄, 西村 文夫
    1999 年 10 巻 1 号 p. 46-51
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    The purpose of this study is to research the change of mechanical properties of dental enamel around the laser irradiated area. CO2 laser and Er: YAG laser were irradiated bovine enamel at 23-161J/cm2, and the its fracture toughness was examined by means of indentation microfracture method.
    The fracture toughness of bovine enamel irradiated by CO2 laser was reduced compared with control at any irradiation energy. On the other hand Er: YAG laser irradiation at all energy condition did not cause the reduction of the fracture toughness.
    These result suggest that Er: YAG laser is useful in preparation of tooth without mechanical changes of enamel around irradiated area.
  • とくに墨汁および水性インクの光透過性と蒸散量との関係
    藤井 孝人
    1999 年 10 巻 1 号 p. 52-60
    発行日: 1999/06/01
    公開日: 2011/06/02
    ジャーナル フリー
    Many studies describing favorable effects of Nd: YAG Laser irradiation during treatment of hard tissue such as treatment and prevention of dental caries, treatment for hypersensitive dentin, root canal treatment, and root planing, etc., have been reported. Suguro has reported that the effect of removal of softened dentin was influenced strongly by special color mediators. The purpose of this study was to investigate the percent transmittance of various color mediators around wavelength in the near infra-red region and the effect of removal of softened dentin by Nd: YAG Laser irradiation associated with their transmittamce. In this study, 4 color mediators (Indialnk mediators: Black Indialnk, Red Indialnk Waterink mediators: Black Waterink, Blue Waterink) were carried out. Each mediator was diluted to 5, 25, 50 and 75% with distilled water and the degree of transmittamce was measured as a percentage under wavelength range of 800-1300nm. To obtain the softened dentin, bovine mandibular incisors (∅5mm×3mm) were treated with Plank-Rhychlo decalcified solution for 5 days, and stained with above color mediators for 30 minutes. They were then dried in a Vacuum Drying Oven prior to supply to the ablation test. The laser irradiations were carried out 10 seconds with a Nd: YAG laser (CW SLT Contact Laser) with a regulated power-range to 5 watts. The rate of ablation was analyzed by comparing the changes in weight before and after irradiation. Stereoscopic and SEM observation were performed on the irradiated surface of each specimens. The following results were obtained: 1) The percent transmittance of Black Indialnk around a wavelengthin the infra-red region was not detected (0.0%). The percent transmittance of other color mediators were increased by decreasing their density.2) The degree of ablation weight was obtained highest in un diluted solution, and decreased parallel with the diluted of their color mediators. 3) There are correlations between the percent transmittance of color mediators and this ablation in the case of Black Watetlnk, Blue WaterInk, Red Indialnk. 4) In stereoscopic and SEM observation, there were no change on the surface of specimens by Red Indialnk and Blue WaterInk, but it was observed deep defect by Black Indialnk, Black WaterInk. They were observed molten surface like a lava at the bottom of the defect in SEM observation.
  • エヌ・エイチ・エム・ カイルール・マティン, 田口 直幸, 伊東 直子, 草刈 玄
    1999 年 10 巻 1 号 p. 61-69
    発行日: 1999/06/01
    公開日: 2011/06/02
    ジャーナル フリー
    感染した接合上皮と結合組織を無菌化することを目的として, 歯周ポケットにCO2レーザーを照射した際の歯肉組織の変化について検討した。実験には, デフォーカス型のCO2レーザーと6頭の雑種成犬を用いた。実験に先立ち, イヌには毎日15~20分のブラッシングを1週間続けて行った。この時点での歯周ポケットは, 最高で3mmであった。実験的な歯肉炎は, 軟食を与えてブラッシングも中止することにより引き起こし, 4週後には平均で1~2mm歯周ポケットが増加した。小臼歯と大臼歯の頬側歯肉45部位に, 0.3から2.5Jの範囲で出力を変化させて照射した。他の15部位については, 照射せずにコントロールとした。照射後7日と14日に, 臨床的および組織学的に歯肉組織の反応を観察した。照射直後には, 軽度の歯肉炎が観察された。組織の破壊程度は出力に関係しており, すなわち最大の組織破壊 (到達深度が1.4mmで創傷領域が0.33mm2) は最高出力 (2.5J) の場合に起こった。7日後には, 照射された歯肉の再上皮化がほぼ完全になされており, 結合組織にも新生したコラーゲン線維が形成されていた。特に0.5~1.5Jの照射出力の時は, コントロールよりも健康的な歯肉が臨床的にも組織学的にも認められた。この時期には, 炎症性の細胞は顕著に減少していた。14日後になると, レーザーを照射した歯肉は完全に治癒し, 傷害を受けた痕跡は全く観察されなかった。今回の実験から, 周囲組織を損傷せずに感染した接合上皮を無菌化することができるCO2レーザーの出力範囲を考察することができた。
  • 池田 久住, 稲葉 大輔, 南 健太郎, 染谷 美子, 米満 正美, 井口 次夫, 高木 興氏
    1999 年 10 巻 1 号 p. 70-75
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
    本研究はレーザー照射の脱灰エナメル質におよぼす影響をin vitroとin situで検討する目的で実施した。人工的に脱灰したエナメル質にQ-switched Nd: YAG第2高調波 (532nm; 100J/cm2) を照射した。続いて, 非照射の対照を含む試料を, pH5の酸性ゲルに3週間浸漬, または上顎第一大臼歯の頬側面に接着して16名の成人口腔内に1か月間接触させた。エナメル質表層のミネラル分布はマイクロラジオグラフィ (TMR) と画像定量法により評価した。paired t-testの結果, いずれの実験においてもミネラルパラメータ値はレーザー照射と非照射試料の間においてP=0.05で有意な違いを示さなかった。結論として, 今回の結果はエナメル質病巣のさらなる脱灰進行が使用したレーザーによっては効果的に抑制されないことを示唆した。
  • 1999 年 10 巻 1 号 p. 77-92
    発行日: 1999/06/01
    公開日: 2010/10/21
    ジャーナル フリー
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