Oral treatment can be frightening for most people, especially extractions and anesthetic injections into the mouth, which can be unnerving and cause many people to miss extractions and other dental treatments because of fear. Effective control of pain and anxiety prior to treatment is what many patients look forward to. Currently, the use of laughing gas inhalation sedation and analgesia has made tooth extraction more humane and comfortable. Patients only need to inhale a small amount of laughing gas to complete the extraction of complex teeth in a relaxed and painless manner. Laughing gas, also known as nitrous oxide (N2O), is a colorless, slightly sweet-smelling gas. A small amount of laughing gas and oxygen inhaled through a special nasal mask can suppress the excitability of the human central nervous system and achieve a sedative and analgesic effect. Initially, the patient remains conscious and somewhat drowsy, but fear and response to painful stimuli are significantly reduced, showing a somatic sedation (children show a reduction in restless movements), while heart rate, blood pressure and respiratory rate are normal. As the dose increases, the patient exhibits a state of sleep, with eyes closed and speechless, reaching full analgesia and allowing complex extractions. Since the residual gas is mainly discharged through the lungs by breathing, and a small amount is also evaporated through the human skin, there is no residual in the body, thus there is no toxic side effect to the human body, safe and reliable, and the patient can leave the hospital after 30 minutes of observation after the surgery. In foreign countries, laughing gas sedation is commonly used in minor surgeries and tooth extractions. The technique can be applied to patients who are particularly afraid of injections and sensitive to pain, and even to patients with high blood pressure and heart disease for tooth extraction. For patients with dental anxiety, with a pronounced vomiting reflex, for children or orthodontic extractions, for minor oral surgery, etc., this technique keeps the patient away from fear and makes it easy to complete the dental treatment.