Objectives <p>Root canal filling is a fundamental step in non-surgical root canal treatment (RCT), required to prevent reinfection or new infection within the root canal system. Traditionally root canal filling uses a sealer in combination with gutta-percha (GP). Here, two cases are presented in which the root canals were filled using only a methacrylic resin-based sealer without GP.</p> Materials and methods <p>Two patients (one male, one female) required RCT – one due to irreversible pulpitis and the other to facilitate a subsequent post-retained protheses. Each RCT was performed according to a standardized procedure, before root canal filling using only methacrylic resin sealer.</p> Results <p>Fillings were completed in curved and straight root canals without evidence of apical extrusion. No clinical symptoms or signs of dissolution were observed during follow-up (24 and 12 months in the respective cases).</p> Conclusions <p>Our findings demonstrate the potential applicability of this novel technique for root canal filling using only a methacrylic resin-based sealer without GP.</p> Clinical relevance <p>The success of our RCT cases offers evidence to support further clinical studies that compare the outcomes with standard root canal procedures.</p>