The goal of this triple blinded randomized clinical trial is to evaluate the effect of combining different bioactive root end filling materials with composite bone graft (xenogeneic mixed with autogenous bone fragments) on the healing process of periapical tissues after endodontic micro-surgery procedure on patients with small to moderate sized lesions. The main questions it aims to answer are:

Will the use of Totalfill in Endodontic surgeries show comparable results to the gold standard MTA? Will the addition of composite bone graft (Xenogenic and Autogenous) affect the healing of small to moderate sized lesions? Is there any interaction between composite bone graft and different bioactive root-end filling materials? Participants were allocated to 4 different groups according to the root-end filling material used with or without bone graft.

Reseachers compared between MTA only group, Totalfill only group, MTA with bone group, and Totalfill with bone group to evaluate healing of the periapical lesion using CBCT after 12 months follow up period.

Inclusion Criteria:

All patients must be medically free from any systemic disease that can affect bone healing.

Age range of the patient should be between 20 - 45 years old. All patients must have good oral hygiene. The size of the radiolucent area is of small-moderate size (up to 3 cm in highest diameter at any axis in CBCT), related to a single rooted maxillary tooth.

Periradicular disease in a root-filled tooth where orthograde root canal treatment options has failed,

Exclusion Criteria:

Patient with systemic disease that may affect bone healing. Patients above 45 years or patients below 20 years. Patients with very poor oral hygiene. Teeth presenting with apico-marginal defects or teeth with periodontal disease (periodontal pockets and/or mobility).

Surgery after previous endodontic surgery (re-surgery cases), root resections and amputations, cases presenting with root fractures.

Patients with history of allergies to any of the medications to be used during or after the surgery.