The study compares the anesthetic efficacy of warm versus conventional 2% lignocaine for inferior alveolar nerve block in mandibular molars, evaluating success rates and onset time.

The study will be conducted following approval from the Institutional Ethics Review Committee, AFID (ANX "A"). A total of 200 eligible patients visiting the Operative Dentistry Department at the Armed Forces Institute of Dentistry will be invited to participate. The procedure will be explained to the patients in Urdu, and written informed consent will be obtained (ANX "B").

Patients will be screened for eligibility through medical history, clinical examination, necessary tests, and peri-apical radiographs. Those meeting the inclusion criteria will be randomly assigned to one of two groups using a scientific random number table.

Group 1: Patients will receive conventional 2% lignocaine (at room temperature).

Group 2: Patients will receive pre-warmed 2% lignocaine (at 42°C). Root canal treatment will begin after the inferior alveolar nerve block (IANB) is administered. 1.8 mL of the local anesthetic will be delivered over 60 seconds using a 27-gauge needle. The first investigator will randomize participants by having them choose one of two differently colored balls to determine which anesthetic preparation (conventional or pre-warmed) they will receive. The conventional 2% lignocaine will be commercially available 2% lignocaine hydrochloride with 1:200,000 epinephrine, while the pre-warmed solution will be heated in a thermostatically controlled water bath or feeder bottle warmer (Philips AVENT) to 42°C.

The second investigator, who will be blinded to group allocation, will evaluate pain immediately after the block is administered by asking patients to rate their discomfort on a Visual Analog Scale (VAS). The onset of anesthesia will also be measured by performing gingival probing every 15 seconds. After rubber dam isolation, access cavity preparation will be performed, and pulp therapy will be initiated by the first investigator. The pulp therapy will be completed as needed, and the teeth will be restored with light-cured composite resin.

Inclusion Criteria:

• Permanent teeth with acutely inflamed pulp without swelling or draining sinus.
• Patient who have carious mandibular molars.
• Patients of either gender aged between 18-50 years old.
• Systemically healthy patients.
• Patients who agree to attend for recall appointments and provide a written consent

Exclusion Criteria:

• Patients on preoperative analgesics and antibiotics.
• Teeth with calcified canals and previously treated teeth.
• Pregnant and lactating mothers.
• Patients who are immunocompromised, anxious and mentally handicapped.
• Patients who are allergic to lignocaine.
• Non-vital or necrosed teeth.