Supervisor : Hossam Mohamed Essam Eldin, Mohamed Mokhtar NagySawares, Sandy Samir Alphonse,2022-01-172022-03-272022-01-172022-03-272017.EG-CaMIUhttps://iorep.miuegypt.edu.eg/handle/20.500.13071/57DISSERTATION NOTE-Degree type M.Sc.DISSERTATION NOTE-Name of granting institution Misr International University, Faculty of Oral and Dental Medicineيشتمل على مستخلص.Includes bibliographic references (p. 64-77)`Root canal Instrumentation is considered the most important and critical phase in endodontic treatment. Mechanical enlargement of the root canal can partially clean and remove contents of the canal. Conjugation between a chemical agent and the mechanical instrument is critical in achieving maximum results. Different root canal irrigants have been suggested and tested. Most of the chemical agents have the disadvantages of being toxic to the surrounding living tissue. However, the chemical action of the root canal irrigant is very essential for total elimination of microorganisms. Sodium Hypochlorite have been the most popular and widely used irrigant over several decades for its unique ability to dissolve root canal contents and its strong antimicrobial action. However, its ability to remove the smear layer and its allergic potential were regarded as major disadvantages. Three dimensional sealing of the root canals have always been the most important goal for successful treatment. Thus, the use of root canal sealers with adequate adhesive properties have been strongly recommended. However, bonding to root canal dentin is affected by multiple factors, among which, the change in chemical nature of dentin induced by root canal irrigants. Hence, a shift toward natural materials as root canal irrigants have been strongly advocated in the last decade. Green tea extract exhibit important biological and pharmacological properties that favored its use in the medical and dental fields. The strong antibacterial action of green tea extract together with being a herbal natural material encouraged its suggestion for usage as root canal irrigant. Reviewing the literature showed several studies testing and comparing the antimicrobial action of green tea, however, its effect on the bonding capacity of the root canal dentin does not appear to be adequately addressed.77 pages : illustrations ; 30 cmtextapplication/pdfengEndodonticstext