A root canal filling material incorporates heat conductive particles of sub-micron size dispersed in a heat flowable matrix of endodontic filling material. The particle size is 1 micron or less (e.g., 0.5 to 1 micron, or nanoparticles of 100nm or less). The addition of high heat conductive particles in the heat flowable matrix material improves the overall heat conductivity of the root canal filling material. During root canal treatment procedure, the filling material softens more thoroughly to fill the root canal apex and to form a seal of higher integrity at the root canal apex area, at a significantly lower operating temperature. The inventive filling material may be provided in bulk (e.g., pellet form) for use with an injection tool that heats and injects softened filling material into root canal cavities, or pre-shaped in the form of dental root canal filling cones (or points).
