Annappa Raghavendra Vivekananda PAI, Ashwini Savia COLACO
European Endodontic Journal - 2026;11(2):37-44
Objective: Duration of laser application is correlated with elevation in root temperature. But studies on the duration of erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser application for gutta percha (GP) removal and temperature elevation are lacking. Therefore, this study was done to comparatively evaluate root temperature with duration taken for GP removal using Er,Cr:YSGG laser. Methods: Forty-two samples obturated with GP were randomly divided into groups I, II, and III (n = 14). In each group, GP obturation was removed with Er,Cr:YSGG laser by employing the same parameters of application. However, the duration taken for GP removal in each group was 8, 10, and 12 minutes, respectively. The external root surface temperature during GP removal was measured at the apical third of samples by using a thermocouple device connected to a digital thermometer. The temperature values in each group were recorded at the end of 8, 10, and 12 minutes, respectively. The data were compiled and statistically analysed by applying 1-way analysis of variance and Tukey post hoc test. Results: Group III showed the highest temperature elevation followed by group II and group I. There were significant differences in the elevated temperature among all the 3 groups (P < .05). Hence, temperature was significantly elevated as the duration taken for GP removal with Er,Cr:YSGG laser increased, and it exceeded the range of critical thermal limit in groups II and III. Conclusion: External root surface temperature exceeds critical thermal limit range, including the recommended thermal limit, as the duration taken for GP removal with Er,Cr:YSGG laser gets longer. Although this needs further clinical validation, GP removal with Er,Cr:YSGG laser application as a sole method must be carried out in as shorter a duration as possible, which should not exceed 5-8 minutes, in addition to adopting various measures to minimise temperature elevation beyond the range of critical thermal and time limits that are deemed detrimental to the surrounding tissues of the root.
