Local anesthesia causes loss of sensibility to pain in a specific area. The mechanism is connected with the ion channels, nerves and depolarisation. There are several types of local anesthesia in dentistry such as topical (spray, gel), the nerve block or infiltration (the dental syringe is used).The most commonly used local anesthetic is procaine. Nerve block is a common form of local dental anesthesia, which blocks the reception of pain in one region of the mouth at a time. Infiltration given inferior to the root the tooth involved in the dental work; used usually for minor procedures such as restorations. Topical anesthetics in spray are used topically to numb various areas before injections or other minor procedures (for example during treatment of children or anxious patients).
Advantages: "painless drilling"; the doctor is not limited by painful manifestation of the patient, so the treatment becomes better and more pleasing for both patient and doctor.