2024-03-29T11:40:08Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/582382022-11-17T02:08:08Zhdl_2115_58230hdl_2115_45744hdl_2115_45742クエン酸応用が3種の水酸化カルシウム製剤の除去と 歯根象牙質の接着性に及ぼす影響Effect of citric acid application on removing three types of calcium hydroxide and adhesiveness to root dentin木村, 慎吾菅谷, 勉鷲巣, 太郎川浪, 雅光Calcium HydroxideUltrasonic irrigationAdhesive root canal sealer水酸化カルシウム超音波洗浄接着性レジン系シーラー根尖封鎖Calcium hydroxide (Ca(OH)2) has been generally used for root canal dressing, however, the remnants of calcium hydroxide reduce the sealing ability of resin-based-sealer. The purpose of this study was to investigate the efficacy of 10% citric acid and 3% ferric chlorite (10-3 solution) on removing three types of calcium hydroxide, and adhesion to root dentin. For experiment 1, extracted human teeth were split longitudinally (crown-to-root direction) into halves. After 300μm groove were prepared, those were reconstituted and fixed. The reassembled root canal was filled with Vitapex® (Vitapex group), Calcipex planeⅡ® (Calcipex group) or Ca(OH)2 mixed with distilled water. (Reagent group) This was stored for 1 or 4 week at 37℃ in 100% humidity and ultrasonically irrigated with ultrasonic file #50 for 60s and the following irrigants, 10-3 solution for 60s and 10% sodium hypochlorite for 30s. The percentage of Ca (OH)2 remnants area was measured microscopically with 40 magnification and was calculated. The dentin surface of the root canal and gap was examined by SEM. For experiment 2, the reassembled root canal was filled with Calcipex planeⅡ®(Calcipex group) or Ca(OH)2 mixed with distilled water (Reagent group). This was stored for 1 or 4 weeks at 37℃ in 100% humidity and ultrasonically irrigated in the same way. A control group root canal was not dressed. A Micro tensile bond strength (MTBS) test and a dye penetration test were employed to evaluate dentin bond strength and leakage between 4-META/MMA-TBB resin sealer (SBS) and the dentin surface of each group. The results were that the percentage of Ca(OH)2 remnants area in the reagent group was lowest and the Vitapex group was highest among all groups at 1 and 4 weeks. The percentage of Ca(OH)2 remnants area in each groups at 4 weeks were a little higher than at 1 week. MTBS of the Calcipex group was significantly less than each of the Reagent group or the Control group. Dye penetration distances of the Calcipex group was significantly more than in the Reagent group and the Control group. No statistically significant difference was found between the Reagent group and the Control group in the MTBS test and the dye penetration test. The viscosity of agents in Vitapex® and Calcipex planeⅡ® might be influenced by removing calcium hydroxide and adhesion. Therefore, it is suggested that Ca(OH)2 mixed with distilled water can be effectively removed and the adhesiveness to root dentin can be recovered.水酸化カルシウムは根管貼薬に広く用いられているが,根管内に残存すると封鎖性を低下させ,とくに接着性レジンシーラーを用いた場合には接着を大きく阻害する.本研究の目的は,3種の水酸化カルシウム製剤に対する10%クエン酸3%塩化第二鉄溶液を用いた除去法の効果,及び除去後の接着への影響を明らかにすることである. 実験1ではヒト抜去単根歯を根管拡大して歯軸方向に分割,機械的清掃が不可能な約300μmの間隙を作製して歯根を復位,固定した.根管内にビタペックス,カルシペックスプレーンⅡ,あるいは水酸化カルシウム試薬と蒸留水を1:1で練和したものを貼薬し,1,4週間後,超音波洗浄を注水下で60秒,10%クエン酸3%塩化第二鉄溶液で60秒,10%次亜塩素酸ナトリウム水溶液で30秒行った.洗浄後,水酸化カルシウム製剤の残存率を計測しSEM観察を行った.実験2では実験1と同様にカルシペックスプレーンⅡ,あるいは水酸化カルシウム試薬と蒸留水を1:1で練和したものを貼薬し,1,4週間後に同様の方法で除去した.さらに無貼薬のコントロールを加え,スーパーボンド根充シーラーを間隙部に接着して,微小引張試験及び色素侵入試験を行った. 水酸化カルシウム残存率は,1,4週後とも水酸カルシウム試薬が最も低く,ビタペックスが最も高かった.1,4週後を比較すると,カルシペックス,水酸化カルシウム試薬のいずれも4週後の方がわずかに残存率は高かった.カルシペックスは1,4週後ともコントロールおよび水酸化カルシウム試薬に比べて有意に微小引張強さが低下し,色素侵入距離も大きかったが,水酸化カルシウム試薬とコントロールとの間には有意差がなかった.これらの差は,各製剤に含まれる基材が原因と考えられた. 以上の結果から,水酸化カルシウム試薬が最も除去されやすく,除去後の接着にも影響しにくいことが示唆された.北海道歯学会Journal Articleapplication/pdfhttp://hdl.handle.net/2115/58238https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/58238/1/35-02-3kimura.pdf0914-7063北海道歯学雑誌3521121222015-03jpnpublisher