Effect of Cryotherapy and Laser Application on Post-Operative Pain in Single Visit Endodontically Treated Symptomatic Apical Periodontitis Cases

Inclusion Criteria: * • Vital teeth display symptomatic apical periodontitis (Symptomatic apical periodontitis was determined based on the clinical symptoms of severe preoperative pain (visual analogue scale \[VAS\] \> 60) and severe percussion pain (VAS \> 60). * Teeth, with a periapical index score (PAI) of 2 or 3 indicating small changes in bone structure and slight mineral loss respectively. * Mobility less than 1 mm in either direction. * Absence of periodontal pocket around the tooth. * Symptomatic pulpitis with spontaneous pain or lingered by cold or heat. * Teeth without pus or inflammatory exudates draining through the canal. * Teeth without anatomic variations Exclusion Criteria: * • Patient with any systemic disease. * Immunocompromised patients. * Pregnant or lactating patients. * Apparently narrow roots in which apical preparation with the #40 file would be overzealous. * Retreatment cases. * Necrotic painful teeth with absence of sinus tract for drainage. * Patients on analgesics or sedative medication up to 6 hours before treatment