Before your procedure begins, the nitrous oxide gas will be administered through a nasal covering. As you gently inhale the gas, it will quickly act to start relaxing you. A member of the SmileArts team will monitor your vital signs and your response to the gas, adjusting the volume as needed throughout the procedure, so you remain comfortable. You may notice tingling in your arms and legs, as well as a feeling of vibration, warmth, euphoria, or well-being as the gas takes effect. Nitrous oxide is normally used along with a local anesthesia such as lidocaine to numb your mouth in the areas being treated. Once the procedure is complete, the gas will be turned off and the effects should quickly wear off.