Abstract
Introduction
This study aimed to evaluate the effect of low-temperature intracanal sodium hypochlorite (NaOCl) irrigation on root surface temperature reduction and its ability to dissolve organic tissue.
Methods
Extracted mandibular premolars were accessed and instrumented. Final irrigation protocols with NaOCl, at two different temperatures: room temperature (control) and 2.5 °C (experimental), were applied. Initial and the lowest root surface temperatures were recorded using a digital thermometer. Organic tissue dissolution was assessed using glass capillaries, filled with catgut, attached to 3D-printed maxillary incisors exposed to the same irrigation protocols. Data was statistically analyzed.
Results
Low-temperature NaOCl irrigation led to a significantly greater reduction in root surface temperature compared to room temperature NaOCl (p < 0.05). Both irrigation protocols showed similar organic tissue dissolution, with no significant difference between them (p > 0.05).
Conclusion
Intracanal irrigation with low-temperature NaOCl effectively reduced root surface temperature while maintaining its organic tissue dissolution capacity.
Clinical relevance
The use of cold sodium hypochlorite represents a simple and effective intracanal cryotherapy approach that may help to minimize postoperative inflammation while preserving the chemical efficacy of the irrigation during endodontic treatment.
Data availability
The dataset generated and analyzed during the current study, including the table of extracted articles, are available from the corresponding author upon request.
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Funding
This study was funded by the “Conselho Nacional de Desenvolvimento Científico e Tecnológico” (CNPq, Brasilia, Brazil) as part of a doctoral research incentive grant. (Number:1610162020-0)
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Authors and Affiliations
Contributions
Conceptualization: M.I.N, E.C.Methodology: M.I.N., P.G.T., U.X.S.Data collection and curation: M.H.D., M.I.N., P.G.T.Analysis and interpretation: U.X.S., V.P.W., B.C.C., M.H.D.Visualization: U.X.S., V.P.W., E.C.Writing – Original Draft Preparation: M.I.N., E.C.Writing – Reviewing and editing: E.C., B.C.C., M.H.D., V.P.W., U.X.S.Supervision: M.H.D., E.C.All authors reviewed and approved the final manuscript.
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The authors declare no competing interests.
Corresponding author
Everdan Carneiro (everdan.carneiro@pucpr.br).
Ethical approval
This study was approved by the local ethics committee (protocol: 64309722.7.0000.0020).
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Iparraguirre Nuñovero, M.F., Hungaro Duarte, M.A., Xavier da Silva Neto, U. et al. Effect of low-temperature intracanal sodium hypochlorite on root surface temperature reduction and organic tissue dissolution: an in vitro study. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37704-7
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DOI: https://doi.org/10.1038/s41598-026-37704-7
