this study aims to evaluate the antimicrobial efficacy of two synthetic (Ibuprofen, Modified triple antibiotic paste) and two herbal materials (Curcumin and Olive leaves extract) used as intracanal medication, against E.Faecalis in secondary endodontic infection cases.

we evaluate the antimicrobial efficacy of two synthetic (Ibuprofen, Modified triple antibiotic paste) and two herbal materials (Curcumin and Olive leaves extract) used as intracanal medication, against E.Faecalis in secondary endodontic infection cases by taking three samples from root canal , the first sample after removing gutta percha from root canal system, the second sample after shaping with protaper universal files and cleaning with 2.5% sodium hypochlorite , the third sample after 7 days from application of the medication .

samples will be diluted into ten fold serial dilution and then the diluted samples will be cultured on bile esculin agar as it is selective media for enterococcus feacalis.

bacterial reduction will be determined and comparision will be made .

Inclusion Criteria:

• Single rooted teeth.
• Teeth have clinical signs and symptoms of endodontic failure as sensitivity to percussion, pain, swelling or fistula.
• Teeth with radiographic features of endodontic failure as persistent periapical lesion or widening of periodontal ligament.

Exclusion Criteria:

• • Teeth with fractures of the crown or root.

  • Teeth with periodontal pocket deeper than 4mm.
  • Teeth have procedural error like ledge, broken instrument, or perforation.