In endodontic therapy, the complete removal of microbes from the root canal system and prevention of reinfection is essential to the overall outcome.
The most effective means of eradicating infection is a combination of chemical and mechanical debridement, because when irrigation is introduced alongside instrumentation the chance of removing inflamed and necrotic pulp tissue, microbes and debris is significantly higher.
As it stands, there is little evidence to prove that certain irrigants are more effective than others, but research has shown that no single irrigant on its own holds all the required characteristics needed to effectively eradicate and prevent infection.[i] Only a combination of two or more solutions in the appropriate sequence can predictably obtain safe and effective irrigation.[ii]
Perhaps the most commonly used irrigant is sodium hypochlorite (NaOCI) in concentrations varying from 0.5 to 6.00%, as this can dissolve organic tissue and has a broad antimicrobial spectrum allowing it to effectively kill biofilms adherent to the root canal walls.[iii] For those who prefer to use sodium hypochlorite, it is worth bearing in mind that a high concentration NaOCI has demonstrated better results than 1% and 2% solutions. [iv] In cases where NaOCI has been used but has been ineffective, it may be that the strength of the formula – or lack of – has compromised the success of the outcome.
The downside of NaOCI is that it does not remove the smear layer. This can be overcome, however with subsequent irrigation with Ethylenediaminetetraacetic acid (EDTA), as it can dissolve inorganic material, including hydroxyapatite. Importantly, EDTA is also biocompatible, able to condition dentine and has shown positive effects on the root canal seal.[v] Nevertheless, it is important to remember that EDTA must be used as a final rinse, not as an alternating rinse with NaOCI.
Another possible irrigant is chlorhexidine digluconate (CHX), which has good antimicrobial activity and is biocompatible. As it is incapable of dissolving organic tissue it cannot replace sodium hypochlorite. One could also opt for hydrogen peroxide, but again, this lacks antibacterial activity when used alone and cannot dissolve tissue.
Whichever combination is used, it is important to choose quality irrigation products from a trustworthy manufacturer of endodontic solutions. At COLTENE, all products are designed and produced using the latest materials and technology to guarantee optimal results. The range of solutions includes CanalPro NaOCI in 3% and 6% formula, CanalPro EDTA 17% and CanalPro CHX 2%, providing all the characteristics needed for effective irrigation. For best results, use alongside HyFlex EDM NiTi root canal files, also available from COLTENE.
The role of irrigation and its impact on the overall success rates of root canal treatment is clear, so be sure to consider your choice of irrigants.
[i] Fedorowicz Z, Nasser M, Sequeira-Byron P, de Souza RF, Carter B, Heft M. Irrigants for non-surgical root canal treatment in mature permanent teeth. Cochrane Database Syst Rev 2012; 9: CD008948. Accessed online January 2018 at https://www.ncbi.nlm.nih.gov/pubmed/22972129
[ii] Haapasalo M, Shen Y, Qian W, Gao Y. Irrigation in endodontics. Dent Clin North Am. 2010; 54 (2): 291-312. Accessed online January 2018 at http://www.endoexperience.com/documents/IrrigationinEndodonticsHaapasalo2010.pdf
[iii] Zehnder M. Root canal irrigants. J Endod. 2006; 32 (5): 389-98. Accessed online January 2018 at https://www.ncbi.nlm.nih.gov/pubmed/16631834
[iv] Haapasalo M, Shen Y, Wang Z, Gao Y. Irrigation in endodontics. Br Dent J. 2014; 216 (6): 299-303. Accessed online January 2018 at https://www.ncbi.nlm.nih.gov/pubmed/24651335
[v] American Association of Endodontists. Root Canal Irrigants and Disinfectants. Chicago: American Association of Endodontists, 2011. Accessed online January 2018 at https://www.aae.org/specialty/wp-content/uploads/sites/2/2017/07/rootcanalirrigantsdisinfectants.pdf