School of Medicine and Dentistry, Griffith University, Gold Coast, Queensland, Australia.
School of Dentistry, The University of Queensland, Queensland, Australia.
Photodiagnosis Photodyn Ther. 2024 Jun;47:104208. doi: 10.1016/j.pdpdt.2024.104208. Epub 2024 May 9.
Bacterial fluorescence methods are of interest in endodontics for informing endpoints for debridement. This study explored potential fluorescence quenching reversal effects of a water-soluble vitamin E conjugate (d-α-Tocopherol polyethylene glycol 1000 succinate, TPGS) when applied to polymicrobial biofilms grown on dentine that had been exposed to sodium hypochlorite (NaOCl) to cause quenching.
Extracted human teeth were debrided, embedded in transparent acrylic resin and sectioned. After smear layer removal, tooth dentine sections were inoculated with a polymicrobial inoculum, and cultured for 7 days to create biofilms. Samples (n = 8 per group) were exposed to 1 % or 4 % NaOCl for 2 or 4 min, and then treated with TPGS. Bacterial fluorescence readings under laser excitation at 655 nm were assessed over 10 min using a calibrated DIAGNOdent device. All data were assessed for normality (Kolmogorov-Smirnov test) and analysed with ANOVA followed by Bonferroni post-hoc tests.
NaOCl at both concentrations quenched fluorescence readings of biofilms grown on dentine samples, with a maximal reduction of 40.4 % at 5 min after 4 % NaOCl. Treatment with TPGS gave faster recovery of fluorescence readings compared to the control at 5 and 10 min.
The water-soluble antioxidant TPGS partially reversed fluorescence quenching caused by NaOCl. This agent may have value clinically for reducing the time needed for fluorescence readings to recover when NaOCl is used as an irrigant. This will facilitate more accurate assessment of endpoints for canal debridement.
在牙髓学中，细菌荧光法可用于为清创的终点提供信息。本研究探索了水溶性维生素 E 缀合物（d-α-生育酚聚乙二醇 1000 琥珀酸酯，TPGS）在应用于因次氯酸钠（NaOCl）导致荧光猝灭而暴露于 NaOCl 的牙本质上生长的多微生物生物膜时潜在的荧光猝灭逆转效应。
从人牙中提取牙本质，并将其嵌入透明的丙烯酸树脂中进行切片。在去除玷污层后，牙本质切片接种多微生物接种物，并培养 7 天以形成生物膜。将样本（每组 8 个样本）暴露于 1%或 4%的 NaOCl 中 2 或 4 分钟，然后用 TPGS 处理。使用经过校准的 DIAGNOdent 设备，在激光激发下（655nm），在 10 分钟内评估细菌荧光读数。使用 Kolmogorov-Smirnov 检验评估所有数据的正态性（正态性检验），并使用方差分析（ANOVA）和 Bonferroni 事后检验进行分析。
两种浓度的 NaOCl 都猝灭了牙本质样本上生长的生物膜的荧光读数，在 4%的 NaOCl 作用 5 分钟后，最大猝灭率为 40.4%。与对照组相比，TPGS 处理在 5 分钟和 10 分钟时使荧光读数更快地恢复。
水溶性抗氧化剂 TPGS 部分逆转了 NaOCl 引起的荧光猝灭。该试剂在临床上可能具有价值，可减少使用 NaOCl 作为冲洗液时荧光读数恢复所需的时间。这将有助于更准确地评估清创术的终点。
