Impacto da conicidade dos instrumentos endodônticos na resistência à fratura dos dentes: uma revisão integrativa

Abstract

This integrative review aimed to compare the different tapers of endodontic instruments used in canal preparation regarding tooth fracture resistance. A search strategy was conducted in the databases PubMed, Cochrane Library, Web of Science, and BVS (Lilacs and BBO), with no restrictions on year or language, using the keywords "root canal preparation" and "flexural strength" and the free terms that were most cited in previous publications on the subject. Two independent reviewers selected studies that met the eligibility criteria in two stages: the first by reading only the title and abstract, and the second by reading the full texts based on the PICOS criteria: 1 – Population (P): endodontically treated teeth; 2 – Intervention (I): endodontic instruments with a greater taper; 3 – Comparison (C): endodontic instruments with a smaller taper; 4 – Outcome (O): fracture resistance; and 5 – Study design (S): laboratory studies.A total of 1,025 articles were found in the databases, and after excluding duplicates, exclusions based on title and abstract review, inaccessibility of articles, studies that were not yet available in full text, and exclusions after reading the full texts, 27 articles remained for data collection. It was concluded that despite some of the articles analyzed in this integrative review, showed results where instruments with a greater taper reduce the fracture resistance of teeth, other studies found no significant difference. It is difficult to reach a definitive conclusion due to the methodological heterogeneity among the evaluated studies. To more accurately assess the impact of the taper of endodontic instruments on tooth fracture resistance, new in vitro studies are needed, with simulations closer to clinical practice and more rigorous control of variables.