LS-O07投与後の歯周ポケット内ミノサイクリン濃度  [in Japanese] Minocycline HCI Concentration in Periodontal Pocket After Administration of LS-007  [in Japanese]

今回の研究の目的は塩酸ミノサイクリンを2%含有する局所投与用の軟膏剤LS-007を歯周ポケットに投与しそのポケット内滞留性を検討することである。被験者は辺縁性歯周炎患者から選び, その4 mm以上の歯周ポケットを有する歯を被験歯とし, 試験薬を注入した。投与後, 1, 3, 7, 24, 48, 72, 120, 168時間後に被験歯のポケット内滲出液を採取し, ミノサイクリン濃度を測定した。時間群間で, 被験歯の歯種別の出現頻度に大きなかたよりはなく, 投与前の歯周ポケットの深さにも有意差はなかった。歯周ポケット内ミノサイクリン濃度は, 投与後7時間まで急遠に減少した。その後の減少はわずかであり72時間後に3.4μg/m1, 120時間後においても0.3μg/m1でこの濃度はポケット内グラム陰性菌の発育阻止濃度に近いものであった。本研究により投与後3日から5日間臨床的に十分なLS-007と思われるミノサイクリン濃度がポケット内に維持されることが示唆された。

As one of clinical procedures for periodontal plaque control, there is a technique to use a bactericidal or bacteriostatic antibiotic directly to periodontal bacteria. Under recent researches are drugs that can be locally administered into the deep periodontal pocket, long sustained there, gradually releasing the active substance. LS-007 is one of such drugs and contains 2% of minocycline HCl. The drug, in the form of ointment, is filled in a specially designed syringe for root-canal treatment, and can be administered into the deep pocket. The objective of our recent study was to investigate the persistence of minocycline HCl in the periodontal pocket after the injection of LS-007 into the pocket of patient with periodontitis. Subjected were patients with chronic periodontitis, aged over 20 years. As test teeth, those with the pocket over 4 mm deep were selected. The test drug was injected to fill up whole the pocket. At 1, 3, 7, 24, 48, 72, 120 and 168 h after administration, the fluid in the pocket was collected by paper strip ; the concentration of minocycline HCl was determined by the HPLC method. There was no much difference in the types of teeth selected for testing between the groups of sampling time ; also, no significant difference was observed in the depth of periodontal pocket, measured before administration, between the groups of sampling time. Minocycline HCl concentrations in the pockets decreased rapidly till 7 h after administration, but the subsequent decrease was very slow, showing the concentration of 3.4μg/ml at 72 h, and 0.1μg/ml at 168 h. The concentrations varied in each sampling time group, but the changes with time showed natural downward curve. The already reported data of MIC 90 for Bacteroides gingivalis, Bacteroides intermedius, and Eikenella corrodens show that at about 100 h after LS-007 administration the concentrations of minocycline HCI are still kept effective on these bacteria.