Our modern facility is equipped with the latest techniques to keep you comfortable during procedures. Here's what you need to know about local anaesthetic, commonly called "freezing."
What is topical anaesthetic?
Before an injection, we apply a gel to numb the surface of your gums. This makes the injection itself much less noticeable. For best results, the gel stays on for 3-5 minutes.
What is local anaesthetic?
Local anaesthetic is what actually numbs your teeth, cheek, lip, or tongue. We inject a solution near the nerve, which temporarily blocks it from sending pain signals.
Most anaesthetics include epinephrine, which helps the freezing last longer and reduces bleeding. If you have a heart condition, let us know—we can use an alternative without epinephrine.
Why does the lower jaw take longer?
The bone in your lower jaw (mandible) is denser, so freezing takes a bit longer to work and lasts longer overall. Your dentist may use a "block" injection that numbs a larger area. Sometimes you'll feel a brief tingle in your lip or tongue—that's a good sign the injection is in the right spot.
How long does freezing last?
According to the Canadian Dental Association:
| Type of Anaesthetic | Upper Jaw | Lower Jaw |
|---|---|---|
| Lidocaine 2% with epinephrine* | 2h 00m | 3h 10m |
| Prilocaine 4% plain* | 1h 45m | 3h 10m |
| Articaine 4% with epinephrine | 3h 10m | 3h 50m |
| Mepivacaine 3% plain | 1h 30m | 2h 45m |
*Used in our practice.
What should I watch for afterward?
The most common issue is accidentally biting your lip, cheek, or tongue while still frozen. Be careful eating or drinking until the numbness wears off completely. If you notice prolonged numbness beyond the expected time, give us a call.