Clinical and Radiographic Evaluation of the Synergistic Effect of Nano Silver Particles and Calcium Hydroxide Versus Triple Antibiotic Paste as Antibacterial Agents for Lesion Sterilization and Tissue Repair (LSTR) in Necrotic Primary Molars

Inclusion Criteria: * Children aged between 4 years and 7 years. * Restorable necrotic mandibular second primary molars * Mandibular lower second primary molar with signs of radiolucency in periapical or furcation area. * Mandibular lower second primary molar with widening of PDL space or loss of lamina dura continuity. * Mandibular lower second primary molar with evidence of internal/external pathologic root resorption. Signs of radiolucency in periapical or furcation area. * Widening of PDL space or loss of lamina dura continuity. * Evidence of internal/external pathologic root resorption. * External root resorption from 1% to 50%. Exclusion Criteria: * Children that are not apparently healthy. * Lack of informed consent by the child patient's parent. * Patients allergic to any antibiotic used in the preparation of the TAP. * Unable to attend follow-up visits. * Refusal of participation. * External root resorption above 50%.