Dental numbing is a routine part of many procedures, designed to ensure patient comfort by temporarily blocking pain signals. This temporary loss of sensation allows dentists to perform treatments without discomfort, knowing sensation will eventually return.
Typical Numbing Duration
The duration of dental numbness varies, but most patients can expect sensation to subside within a few hours. This timeframe depends on the specific numbing agent and the treated area. For instance, lidocaine typically provides numbness for 2 to 4 hours. Articaine also wears off within 2 to 4 hours, while mepivacaine usually subsides within 1 to 2 hours. Bupivacaine, known for its prolonged effect, can keep an area numb for 4 to 9 hours, with soft tissue numbness lasting up to 12 hours.
Soft tissue numbness, affecting the lips, tongue, and cheeks, often lasts longer than the numbing sensation in the tooth itself. For example, lidocaine might numb a tooth for about an hour but keep soft tissues numb for 3 to 5 hours.
Influences on Numbing Duration
Several factors influence how long dental numbing lasts. The type of anesthetic used is a primary determinant, as different agents have distinct durations of action.
The presence of a vasoconstrictor, such as epinephrine, extends the numbing effect. Vasoconstrictors constrict blood vessels, slowing the anesthetic’s absorption into the bloodstream and prolonging its presence at the injection site.
The injection site also plays a role. Numbing near major nerves, such as block injections for the lower jaw, often results in a longer duration of numbness compared to localized infiltration.
An individual’s metabolism affects how quickly their body processes and eliminates the anesthetic. People with faster metabolisms may find numbness wears off more rapidly. Overall health conditions, particularly those affecting the liver or kidneys, can also influence drug breakdown.
Inflammation or infection in the area can sometimes reduce numbing effectiveness and duration. Inflamed tissues can have a lower pH, affecting how local anesthetics penetrate nerve membranes. Increased blood flow in inflamed tissues can also promote faster absorption and removal of the anesthetic.
Coping While Numb
Managing the period of numbness after a dental procedure requires careful attention to avoid accidental injury. Avoid chewing or eating until numbness completely wears off, as you might inadvertently bite your tongue, cheek, or lip. This precaution helps prevent soft tissue trauma.
Exercise caution with hot or cold beverages. The lack of sensation means you might not accurately gauge the temperature, risking burns or discomfort. Stick to soft, cool foods if you must eat before sensation returns.
While numbness persists, you might experience difficulty speaking or managing drooling. Gentle movements of the jaw, lips, and tongue can sometimes stimulate blood flow and help sensation return more quickly. Applying a warm compress to the face, if approved by your dentist, can also aid in increasing blood circulation.
When Numbness Lingers
While dental numbness typically resolves within a few hours, it might occasionally last longer than expected. If numbness persists beyond 24 hours, contact your dentist. Prolonged numbness could indicate nerve irritation or, in rare cases, nerve damage.
Conditions like paresthesia, which is persistent numbness or an altered sensation like tingling, can occur in specific nerves such as the inferior alveolar nerve affecting the lower jaw and lip, or the lingual nerve affecting the tongue. While uncommon, these occurrences warrant professional evaluation. Your dentist can assess the situation and determine if any intervention is necessary.