EFFECT OF LOW-TEMPERATURE INTRACANAL SODIUM HYPOCHLORITE ON ROOT SURFACE TEMPERATURE REDUCTION

INTRODUCTION: Intracanal cryotherapy, delivered through cooled irrigants, has been used as a low-cost therapeutic strategy to reduce postoperative pain and inflammation following endodontic treatment. Sodium hypochlorite (NaOCl) is the most widely used irrigant in endodontics due to its antimicrobial properties and its ability to dissolve organic tissue; however, few studies have evaluated the effect of its cooling on root surface temperature. AIMS: To assess whether the external temperature of the apical four millimeters of the root surface can be reduced by continuous irrigation with NaOCl cooled to 2.5°C, compared with irrigation using NaOCl at room temperature. MATERIALS AND METHODS: Intracanal cryotherapy, delivered through cooled irrigants, has been used as a low-cost therapeutic strategy to reduce postoperative pain and inflammation following endodontic treatment. Sodium hypochlorite (NaOCl) is the most widely used irrigant in endodontics due to its antimicrobial properties and its ability to dissolve organic tissue; however, few studies have evaluated the effect of its cooling on root surface temperature. Objectives: To assess whether the external temperature of the apical four millimeters of the root surface can be reduced by continuous irrigation with NaOCl cooled to 2.5°C, compared with irrigation using NaOCl at room temperature. RESULTS: Irrigation with NaOCl at room temperature promoted a slight, though statistically significant, mean reduction of 0.9°C in root surface temperature (p<0.001). In the experimental group, irrigation with cooled NaOCl produced a substantially greater reduction, with a mean decrease of 8.3°C (p<0.001). No significant difference was observed between groups regarding initial temperature; however, the lowest temperature achieved in the experimental group was significantly lower than that observed in the control group. FINAL CONSIDERATIONS: It can be concluded that intracanal irrigation with NaOCl cooled to 2.5°C significantly reduces the external root surface temperature when compared with NaOCl at room temperature, suggesting that this approach may represent a simple and effective alternative for performing intracanal cryotherapy, contributing to the control of postoperative pain and inflammation in endodontic treatment.

PALAVRAS-CHAVE: Sodium hypochlorite; Cryotherapy; Endodontics; Root temperature; Root canal irrigation.