歯内療法における光線力学療法の抗菌効果の分子解析。A case series

Molecular Analysis of the Antibacterial Effects of Photodynamic Therapy in Endodontic Surgery: A Case Series.

抄録

このケースシリーズでは，歯内療法の際に使用される抗菌性光線力学療法（PDT）によって促進される細菌の減少を評価した。また、症例はフォローアップされ、手術結果も報告された。本研究では，歯内療法で連続して治療された治療後の先端歯周炎の歯19本を対象とした．アピコエクトミーの後，根端にメチレンブルーを光増感剤とするPDTを行った。PDTの前後に，切断した歯根表面と歯根端の空洞の両方から細菌学的サンプルを採取した。サンプルは，定量的リアルタイムポリメラーゼ連鎖反応を用いて，総細菌数とStreptococcus群数を分析した。EndoSequence BC-RRM Putty（Brasseler, Savannah, GA）を根端充填剤として使用した。患者の追跡調査を行い，手術成績を評価した。PDTアプローチ後の細菌数の減少をノンパラメトリックなWilcoxon signed rank testを用いて解析した。PDTは，歯根端の空洞と切除された歯根面の両方で，総細菌数と連鎖球菌数を有意に減少させた（P<.05）．12～21ヵ月後にリコールが可能となった15本の歯の成功率は，緩い評価基準では93％，厳格な評価基準では73％であった．歯内療法の際にPDTを使用することで，切断面と歯根端の空洞の消毒が有意に促進された。PDTで治療した症例は高い治癒率を示した。

In this case series, bacterial reduction promoted by antimicrobial photodynamic therapy (PDT) used during endodontic surgery was evaluated. Cases were also followed up, and the surgical outcome was reported. The study consisted of 19 teeth with posttreatment apical periodontitis that were consecutively treated by endodontic surgery. After apicoectomy, the root end was treated with PDT using methylene blue as the photosensitizer. Bacteriologic samples were taken from both the cut root surface and the root-end cavity before and after PDT. Samples were analyzed for the total bacterial and Streptococcus group counts using quantitative real-time polymerase chain reaction. EndoSequence BC-RRM Putty (Brasseler, Savannah, GA) was used as the root-end filling. Patients were followed up, and the surgical outcome was evaluated. The reduction in bacterial counts after the PDT approach was analyzed using the nonparametric Wilcoxon signed rank test. PDT significantly reduced the total bacterial and streptococcal counts in both root-end cavities and resected root surfaces (P < .05). The success rate for 15 teeth that were available for recall after 12 to 21 months was 93% under a loose evaluation criterion and 73% under a rigid one. Used during endodontic surgery, PDT significantly enhanced disinfection of the cut surface area and root-end cavity. Cases treated with PDT showed a high healing rate.