Evaluation of The Effect of 980nm Diode Laser Intracanal Irradiation on Levels of Interleukin-8 Expression

This clinical trial will be conducted to evaluate the amount of Il-8 expression before and after the application of intracanal irradiation with diode laser 980 nm versus placebo in failed endodontic cases with periapical lesions.

Inclusion Criteria:failed previously treated endodontic single-rooted teeth with chronic periapical lesions; with radiographic evidence of periapical radiolucency of not less than 1 cm diameter will be selected.Teeth with straight root canals.No contributory medical history.No previous administration of analgesics and/or antibiotics within the previous 2 weeks.Exclusion Criteria:Retreatment cases with complications such as separated instruments, perforations, ledges, resorption, transportation, calcifications, immature apices and over fillings.Teeth with curved roots.Swelling or sinus tract.Mutilated teeth that interfere with proper isolation and seal between visits.Subjects with generalized periodontitis, or if the tooth has a probing depth of more than 3 mm.Subjects with uncontrolled diabetes or debilitating diseases.Pregnant or nursing females.Systemic disorders that necessitate antibiotic prophylaxis or prevent the use of Ibuprofen.