The aim of this study was to compare the effects of Lidocaine/epinephrine with and without Sufentanil on the rate of anesthesia after supplemental intraligamentary injection (PDL) in teeth with irreversible pulpitis.

Inclusion Criteria:

• patients in the age group of 18-65 years old
• healthy (ASA I, II)
• patients with first or second mandibular molars who need endodontic treatment
• vital tooth without a history of past endodontic treatment
• patients with clinical evidence of irreversible Pulpits with moderate to severe pain
• patients who signed consent form
• patients numbness at the lateral edge of the lips after inferior alveolar injection (INA) and those with positive respond to maximum output of pulp tester after INA.

Exclusion Criteria:

• pregnant or nursing
• necrotic tooth
• patients with allergy or contraindication toward non-opioid or opioid painkillers such as aspirin or NSAIDs
• Patients who have taken opioid or non opioid or steroid pain killers, antidepressants or sedative drugs in the past 48 hours
• patient with infectious diseases
• patient with moderate to sever periodontal disease
• those without numbness at the lateral edge of the lips after inferior alveolar injection (INA), and those do not respond to maximum output of pulp tester after INA.