The present invention relates to the deposition of a micro-crystalline hydroxyapatite and tricalcium phosphate coating onto gutta-percha cones, to be used as dental composite for root canal filling. The method proposed for coating involves the surface pretreatment of gutta-percha cones with sodium hydroxide; immersion of gutta-percha cones in simulated body fluid, which contains calcium and phosphate ions; and replacing consumed simulated body fluid after an interval of time, at physiological pH and temperature. The nucleation process results in the biomimetic deposition of a thin and uniform layer of calcium phosphates and hydroxyapatite. Improved characteristics such as in sealing ability, bonding strength, and ability to form hermetic seal, therefore allows the dental composite produced, to be used appropriately as filling matter in root canal treatments.