INTRODUCTION: THE PURPOSE OF PULPECTOMY TREATMENT IN PRIMARY TEETH WITH NECROTIC PULP, REMOVES MICROORGANISMS FROM THE CANAL. LSTR (LESION STERILIZATION AND TISSUE REPAIR) IS A NONINSTRUMENTATION ENDODONTIC TREATMENT THAT EMPLOYS A MIXTURE OF ANTIBACTERIAL DRUGS IN A PROPYLENE GLYCOL VEHICLE FOR THE DISINFECTION OF DENTINAL, PULPAL, AND PERIAPICAL LESIONS. …