What is a Dental Block?

Dental blocks are nerve blocks that are frequently used to
provide anesthesia for the facial soft tissue.This procedure is performed by infiltrating local anesthesia intraorally
in the area of the infraorbital and mental nerves.This effectively provides anesthesia of the
upper and lower lip and surrounding areas.This approach provides excellent anesthesia which is almost instantaneous.This
type of block is frequently used for facial plastic surgery.It has a high success rate and is associated
with excellent pain management.

Many patients can tolerate filler injections into many areas of the face with simple topical techniques such as ice or numbing cream. However, it's rare that patients are comfortable with these techniques when injecting the lips. Because of the density of nerves in the lips they are very sensitive.
In my experience, the great majority of patients benefit from dental blocks - two injections for the upper lip and two injections for the lower lip. These dental block injections are quick and make the remainder of the procedure pain free.
You can certainly try to tolerate a lip injection without the blocks, but if you're doctor doesn't feel comfortable using blocks, I would recommend you seek out other options.
Hope thats helpful

I use dental blocks for anyone having lip filler injected. A dental block is done by injecting lidocarine (numbing medicine) into 2 or 4 of the sensory nerves to the lips. Two are injected if only the upper or lower lip is being treated; 4 are injected if both lips are being treated. The numbing injections are done through the mouth and take just a quick few seconds. Then you're pain-free for your lip treatment.

"Dental blocks" refers to the intraoral (in the mouth) injections of local anesthetic that a dentist uses to anesthetize areas of the mouth for dental work.
These same techniques have been used by plastic surgeons for years and years to perform surgical procedures as well. I often will perform these "blocks" to anesthetize areas of the face so that when I inject a patient's lips with Juvederm/Restylane it is comfortable for them.