INTRODUCTION: restoring endodontically treated teeth involves treating dentin with disinfectants and acidic substances that improve adhesion but generate structural irreversible changes. The objective of this article was to describe and analyze the changes in structure and mechanical properties produced by 5.25% sodium hypochlorite, 17% ethylenediaminetetraacetic acid (EDTA), and 2% chlorhexidine on endodontically treated dentin, as described in the literature. METHODS: the following databases were consulted: Scient Direct, Pubmed, Scielo, and EbscoHost, using these keywords: Human and Root Canal and Human and Change, Dentin and Treated dentin and Chlorhexidine. We selected 67 articles that met these criteria: thoroughly describe dentin changes when it is irrigated with 5.25% sodium hypochlorite and 17% ethylenediaminetetraacetic acid (EDTA), and 2% chlorhexidine at different treatment stages. RESULTS AND CONCLUSIONS: : we found out that treated dentin suffers changes in terms of dentinal architecture loss, ionic content and organic matrix, and reduction in microhardness, nanohardness, and compressive and tensile strength. Endodontically treated dentin is a chemically altered substrate with affected properties and poor adhesion durability.