Haenni S, Schmidlin P R, Mueller B, Sener B, Zehnder M
Division of Endodontology, Department of Preventive Dentistry, Cariology, and Periodontology, Center for Dental Medicine, University of Zürich, Switzerland.
Int Endod J. 2003 Feb;36(2):100-5. doi: 10.1046/j.1365-2591.2003.00629.x.
Chemical and antimicrobial effects of paste-like suspensions of calcium hydroxide (Ca(OH)2) powder with chlorhexidine (CHx), sodium hypochlorite (NaOCl) or iodine potassium iodide (IPI) solutions were tested and compared to conventional Ca(OH)2/saline paste.
Equivalent mixtures of Ca(OH)2 with irrigating solutions were compared to conventional Ca(OH)2/saline paste for their ability to raise the pH in root dentine. Ca(OH)2 pastes were compacted into prepared root canals of single-rooted extracted human teeth. Changes in root pH over time were recorded with a microelectrode placed in standardized wells within root surfaces. Antimicrobial efficacy of test solutions and pastes against Enterococcus faecalis and Candida albicans was assayed using an agar diffusion test.
The ability of Ca(OH)2 to raise the pH in the root dentine was maintained when using mixtures of Ca(OH)2 with CHx, NaOCl or IPI (Kruskal-Wallis, P > 0.05). Mixtures of Ca(OH)2 with the test solutions had similar antimicrobial properties as equivalent mixtures with saline (anova, P > 0.05). The efficacy of CHx was reduced when mixed with Ca(OH)2. No additive antiseptic effects were recorded between Ca(OH)2 and IPI or Ca(OH)2 and NaOCl.
Ca(OH)2 is a strong alkali, whose pH is not changed when adding weak acids or alkalis in aqueous suspensions. Under the conditions of this study, mixing Ca(OH)2 powder with the test irrigating solutions did not provide an increased antimicrobial effect compared to a conventional Ca(OH)2/saline medication.
测试氢氧化钙（Ca(OH)₂）粉末与洗必泰（CHx）、次氯酸钠（NaOCl）或碘化钾碘（IPI）溶液的糊状悬浮液的化学和抗菌作用，并与传统的Ca(OH)₂/盐水糊剂进行比较。
将Ca(OH)₂与冲洗液的等效混合物与传统的Ca(OH)₂/盐水糊剂在提高牙根牙本质pH值的能力方面进行比较。将Ca(OH)₂糊剂压实到单根拔除的人牙制备好的根管中。用置于牙根表面标准化孔内的微电极记录牙根pH值随时间的变化。使用琼脂扩散试验测定测试溶液和糊剂对粪肠球菌和白色念珠菌的抗菌效果。
当使用Ca(OH)₂与CHx、NaOCl或IPI的混合物时，Ca(OH)₂提高牙根牙本质pH值的能力得以维持（Kruskal-Wallis检验，P>0.05）。Ca(OH)₂与测试溶液的混合物具有与等效盐水混合物相似的抗菌性能（方差分析，P>0.05）。CHx与Ca(OH)₂混合时其效力降低。未记录到Ca(OH)₂与IPI或Ca(OH)₂与NaOCl之间的附加防腐作用。
Ca(OH)₂是一种强碱，在水性悬浮液中加入弱酸或弱碱时其pH值不变。在本研究条件下，与传统的Ca(OH)₂/盐水药物相比，将Ca(OH)₂粉末与测试冲洗液混合并未提供增强的抗菌效果。
