8.4% sodium bicarbonate will be added to the 4% articaine HCL with 1:1000000 epinephrine carpule in ratio 19:1 the Articaine to the Sodium bicarbonate

4% Articaine HCL with 1:1000000 epinephrine Anaesthetic carpule

Buffered local anesthesia will be administered after being previously prepared just before the injection time.

Buffering Local Anesthetic Solutions Using 8.4% Sodium Bicarbonate in a 19:1 Ratio: Using the "REMOVE AND REPLACE hand buffering method"

-Under sterile conditions, 0.09 mL of local anesthetic solution will be removed from the cartridge using a 0.5 mL syringe with a 28- gauge, 0.5-inch needle (Kendall Monoject Insulin Syringe [Tyco Healthcare, tyco.com] lot number 027501). Using a separate unused syringe, 0.09 mL of the commercially available 8.4% sodium bicarbonate will be removed from the 50 mL vial and immediately injected into the local anesthetic cartridge. The cartridge will be inverted 5 times to mix the solution, and no precipitation will be present.

Sound, Eye, Motor (SEM) Scale (Appendix II), will be used as an objective method for pain assessment. It comprises the following parameters: (1) Sound, (2) Eye, (3) Motor. For each child, the sounds, eye symptoms and body movements will be evaluated by the operator using the recorded video tapes. The slightest manifestations of the sound, eyes, or motion of the patient is graded in four levels: comfort, mild, moderate, and severe discomfort, and subsequently given grades 1 (comfort), 2 (mild discomfort), 3 (moderate discomfort), and 4 (severe discomfort), respectively. SEM score will be calculated by summing the three grades of the parameters

Current Perception Threshold (CPT) detection using Transcutaneous Electric Nerve Stimulator (TENS) device. CPT baseline value is the lowest intensity at which the patient first report feeling the stimulus. It determines the Sensory Threshold (ST), which corresponds to the lowest current intensity capable of eliciting perception. The electrode will be placed on the proposed measuring site and the device will be turned on. The device will start the delivery of current at the lowest output intensity and then slowly increased until the patient reported feeling the stimulus. Patients will be instructed to state if they feel any sensation, at that time the delivery of electrical current will be terminated and CPT intensity will be recorded. Every 30 seconds after administration of anaesthesia, while set at the baseline CPT intensity recording for each patient, the electrode will be applied to the proposed measuring site on the anesthetized side, to detect the time of onset of anaesthesia.

This will be determined through completion of the procedure without pain with no need for additional anaesthetic injection.