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Procedures

Local anesthetic

Procedure overview

Learn about the dental procedure, when it is generally prescribed, and other information which can increase your knowledge of the topic.

Alternate terms: Anesthetic; Novocaine.

Local anesthetic is an artificially induced, temporary disconnect from motor and sensory nerve transmission to allow performance of procedures that have the potential to cause significant discomfort. Think of it like a circuit breaker. When a breaker is turned off, work within the electrical circuit may be safely accomplished. Local anesthetic is typically administered via injection, and is commonly referred to as "novocain". There are several local anesthetics in common use today, and novocain itself is seldom used in dentistry.

Procaine, or novocaine, which provided comfortable dental procedures for many years.

Figure 1: Artist's rendering of the procaine (novocaine) molecule, which made comfortable invasive dental procedures a reality for many years.

Local anesthetic is normally administered when a dental procedure has the potential of producing discomfort, to eliminate any unpleasant sensation during the procedure. Certain local anesthetics contain ingredients called "vasoconstrictors", and are used to control localized bleeding for surgical procedures. Vasoconstrictors also help to keep the local anesthetic confined to the area of the dental procedure, and reduce their potential to cause adverse systemic effects.

On May 9, 2008, The United States Food and Drug Administration officially approved the use of a local anesthetic reversal agent known as OraVerse (phentolamine mesylate), which is manufactured by Novalar Pharmaceuticals, Inc. The drug is given by injection and can reduce the duration of anesthesia (numbness, drooling) by approximately 80-90 minutes. It has not been studied and is currently not recommended in children under the age of six. In clinical trials, near normal sensation was achieved in under one hour from the time of injection for 41% of patients whose lower lip was anesthetized, and 59% of patients whose upper lip was anesthetized.

In trials, the most commonly reported side effect of the drug was temporary soreness at the injection site. Although this class of drugs can elevate heart rate and cause abnormal heart beat (arrhythmia), these effects are reportedly uncommon with OraVerse, and no serious side effects were noted in the studies. Approval of the reversal drug was based on two randomized, double-blinded, placebo-controlled clinical studies involving 484 patients. The drug's main use is anticipated to be avoidance of soft tissue injuries (e.g. from cheek/lip biting) while the soft tissues are still numb. Some patients will appreciate the convenience of returning to normal sensation sooner than was previously possible.