How Long Does Dental Freezing Last?

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Another term for dental freezing is a dental anesthetic, which is a type of medication applied before a dental procedure or oral surgery to reduce or even eliminate the loss of feeling or sensation, to effectively reduce pain.

There are generally three different types of dental freezing or anesthetics:

  • Local anesthesia: medication that is injected near the oral nerve to numb the teeth and surrounding area. It generally works by blocking the nerve(s) from generating an impulse and thus blocking your pain.


  • Topical anesthesia: the medication is administered on the surface of your mouth, applied to numb the area. 
  • General anesthesia: general anesthesia, as the name suggests, is the anesthesia that when administered, will affect the whole body and (might) cause the patient to lose consciousness. Pretty rarely applied during oral surgery or dental procedures, but general anesthetics might be applied in specific cases.


Since the first two types of freezing/anesthetics are more commonly applied in any dental procedure, we will mainly discuss them.

Full Freezing or  Local Anesthesia

Local anesthetic, or “full” freezing, as mentioned above, is achieved by administering an anesthetic solution near an oral nerve, numbing your teeth, gums, cheek lips, and/or tongue as required by the dental procedure.

If necessary, vasoconstrictor drugs (to narrow blood vessels) are applied to slow down the intake of the numbing agent and prolong the freezing duration. The vasoconstrictor agent decreases blood flow and increases the numbing/freezing duration.

Epinephrine (or adrenaline) is one of the most common anesthetic drugs used in this full freezing process, but since it can rapidly increase heart rate, patients with heart disease or heart conditions should avoid epinephrine or any vasoconstrictor agent in general.

This is why informing your dentist about your medical history and your overall health is very important before any dental procedure or oral surgery.

Superficial Freezing or Topical Anesthesia

Superficial freezing or topical anesthetic is, as mentioned, the process of numbing the surface of the oral mucosa (the surface membrane lining inside the mouth). This can be done before the injection of the full freezing (so the patient won’t feel too much pain during the injection).

However, for simpler and “lighter” dental procedures, topical anesthesia alone might be sufficient.

How Long Does Dental Freezing Last?

The answer to this question will depend on two main factors:

  1. Whether the freezing is applied/administered on the mandible or maxilla
  2. The type of anesthetic drug administered

Freezing Duration: Maxilla VS Mandible

The mandible is, in a nutshell, our lower jawbone, while maxilla is the upper jawbone.

The mandible is denser than the maxilla, and so when local anesthetic or full freezing is administered, it’s going to take longer to take effect, but at the same time, it will generally last longer.

When the local anesthetic is going to be applied to the mandible, generally the dentist/anesthesiologist will use block injection (anesthetic targeted toward a certain nerve or nerve group).

On the other hand, when the injection is applied to the maxillary arch, the anesthetic agent can reach the bone and the roots of your teeth easily, because the maxilla area is more porous than the mandible. However, freezing applied to the maxilla area also won’t last as long.

Type of Anesthetics

Below are the common types of anesthetic drugs used in a dental procedure, and the approximate duration of the freezing effect.


  • Bupivacaine 0.5% with epinephrine


7 hours 30 minutes for mandibular injection, 5 hours 40 minutes for the maxillary injection


  • Articaine 4% with epinephrine


3 hours 50 minutes for mandibular injection, 3 hours 10 minutes for the maxillary injection


  • Prilocaine 4% with epinephrine


3 hours 40 minutes for mandibular injection, 2 hours 20 minutes for the maxillary injection

  • Mepivacaine 2% with levonordefrin


3 hours 5 minutes for mandibular injection, 2 hours 10 minutes for the maxillary injection

  • Lidocaine 2% with epinephrine


3 hours 10 minutes for mandibular injection, 2 hours exact for the maxillary injection


  • Prilocaine 4% plain


3 hours 10 minutes for mandibular injection, 1 hour 45 minutes exact for the maxillary injection


  • Mepivacaine 3% plain


2 hours 45 minutes for mandibular injection, 1 hour 30 minutes exact for the maxillary injection

How To Help Freezing Wear Off Faster

In general, anesthetic or freezing effects wear off when the drug is carried away in the bloodstream, and as you can see above, the effects may fully wear off within 1-7 hours, and most of them will completely wear off before three hours. If a vasoconstrictor drug is applied, then the effects will only start to wear off once blood circulation increases.

However, some people may want to speed up the process for one reason or another, and in general, here are some things you can try to speed up the process:

  • Full freezing or local anesthetic may be broken down faster if the person engages in an active physical activity (walking, running, etc.) to increase blood circulation. However, consult with your dentist and/or physician whether engaging in an exercise is okay for your recovery period.
  • The dentist might prescribe medications to relieve the numbing/freezing effect faster. In most cases, however, insurance won’t cover this type of medicine.

End Words: Possible Side Effects and Complications

In virtually all cases, dental freezing performed by a certified dentist or anesthesiologist is completely safe and shouldn’t produce any complications or side effects. However, as with any medical procedures and medications, it is wise to be careful and aware of possible complications.

Although it’s very rare, complications such as injection of air into a blood vessel (which can rupture the blood vessel) are possible. Conditions like paresthesia freezing that last longer than it should, or freezing that wore off before the procedure is completely done, are also possible.

However, most commonly occurred side effects and complications aren’t serious and are quite easily avoided. Make sure to work with an experienced dental specialist to ensure this.

If you need peace of mind about your dental freezing for any dental procedure, give us a call at Markham Stouffville Smile Centre, and our team of friendly dental specialists are always happy in assisting your case.

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