Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
J Mater Sci Mater Med. 2021 Dec 7;32(12):150. doi: 10.1007/s10856-021-06607-6.
The objective of the present work was to evaluate the ultrasonic agitation, time and vehicle (propylene glycol or distilled water) on the antimicrobial potential and penetrability of calcium hydroxide pastes on infected dentin by means of Confocal Laser Scanning Microscopy (CLSM) and microbiological culture (MC).
Dentin specimens were infected with Enterococcus faecalis using a new contamination protocol of 5 days. The specimens were divided into eight groups and dressed with the pastes for 7 or 15 days: G1) calcium hydroxide (CH) + propylene glycol (prop)/7 days (d), G2) CH + prop/7d + ultrasonic agitation (U), G3) CH + distilled water (dw)/7d, G4) CH + dw/7d + U, G5) CH + prop/15d, G6) CH + prop/15d + U, G7) CH + dw/15d, G8) CH + dw/15d + U. The ultrasonic activation was made for 1 min in both directions with a plain point insert. After medications removal, the images obtained by CLSM showed the viable (green) and dead (red) bacteria with Live and Dead dye. By the MC, the dentinal wall debris obtained by burs were collected for colony counts. For the penetration test, the Rodamine B dye was added to the CH pastes and analyzed by CLSM.
The 7 and 15-days CH + prop+U pastes performed better antimicrobial efficacy, followed by the CH + dw+U/15d paste.
All pastes demonstrated better penetration and antimicrobial activity against E. faecalis when agitated with ultrasound, even in periods of up to seven days. The propylene glycol vehicle showed better results.
Agitation of the dressing that remains for less time inside the root canal can optimize the decontamination of endodontic treatment.
本研究旨在通过共聚焦激光扫描显微镜（CLSM）和微生物培养（MC）评估超声搅拌、时间和载体（丙二醇或蒸馏水）对氢氧化钙糊剂在感染牙本质上的抗菌潜力和渗透性的影响。
使用新的 5 天污染方案，用粪肠球菌感染牙本质标本。将标本分为 8 组，用糊剂处理 7 或 15 天：G1）氢氧化钙（CH）+丙二醇（prop）/7 天（d），G2）CH+prop/7d+超声搅拌（U），G3）CH+蒸馏水（dw）/7d，G4）CH+dw/7d+U，G5）CH+prop/15d，G6）CH+prop/15d+U，G7）CH+dw/15d，G8）CH+dw/15d+U。超声激活以两种方向进行 1 分钟，使用普通点插入物。药物去除后，通过 Live and Dead 染色，CLSM 获得的图像显示活菌（绿色）和死菌（红色）。通过 MC，用旋转锉收集牙本质壁碎片进行菌落计数。对于渗透试验，将罗丹明 B 染料添加到 CH 糊剂中并通过 CLSM 进行分析。
CH+prop+U 糊剂在 7 和 15 天的抗菌效果更好，其次是 CH+dw+U/15d 糊剂。
所有糊剂在超声搅拌下的渗透性和抗粪肠球菌活性均优于对照组，即使在 7 天内。丙二醇载体显示出更好的效果。
根管内保持时间较短的敷料的搅拌可以优化根管治疗的消毒效果。
