Investigation of different sodium hypochlorite volumes, concentrations and times of irrigation in endodontic therapy: a systematic review

José Alcides Almeida de Arruda, Lauren Frenzel Schuch, Adzo Pereira, João Luiz Gomes Carneiro Monteiro, Paulo Maurício Reis Melo-Júnior, Ricardo Alves Mesquita, Amália Moreno, Gerhilde Callou


Although the sodium hypochlorite (NaOCl) solution has been part of the endodontic arsenal for more than one century, current investigations have been unable to determine which NaOCl volume and concentration or which time of application are able to dissolve organic matter without weakening the dental structure during the phase of biomechanical preparation of the root canal. Thus, the objective of the present study was to conduct a systematic literature review with no restriction of publication year or language in order to resolve these questions. The search strategy included the following databases: PubMed, LILACS, Web of Science and, and only in vivo human clinical trials were included in the final review. After the removal of duplicates, the systematic literature review yielded 3,717 articles. Of these, 3,685 were excluded after applying the exclusion criteria (ex vivo studies, animal studies, cell-culture studies, narrative review, and studies with no available full texts). A total of 32 full-text articles were assessed for eligibility. After evaluating the full text, all articles were excluded for different reasons. No studies fulfilled our inclusion criteria. This review was unable to answer what time of irrigation, concentration or volume of NaOCl solution can be of maximum effectiveness in endodontic treatment without producing significant changes in the mechanical properties of dentin. Thus, future human clinical studies are needed in order to resolve these questions.

Descriptors: Endodontics; Sodium Hypochlorite; Review.


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