Is It Normal for the Lower Lip to Feel Numb Weeks After Chin Implant?

After a chin implant, there is swelling and edema for approximately two months after the surgery. The mental nerve is located just above the implant, and there is a normal course of numbness after the chin implant procedure for approximately one to two months. There is a rare occasion whereby the numbness might be permanent after a chin implant.

Hello! Thank you for your question! Numbness after any surgical
procedure is expected for several weeks to months following. As the
nerves to the area are traumatized and will then experience a temporary
neuropraxia, a transient loss of nerve conduction. This usually
resolves over the next 6-12 weeks, but depending on the procedure
performed, sometimes much longer. Typically this should resolve by 1
year. As it goes past this date, the likelihood of the sensation
returning is small. However, it can take up to 2 years. If no return
from there, it is unlikely to return. It should be discussed that
persistent sensory changes may develop following any surgical
procedure.  The mental nerve may have neuropraxia or less likely damage.  The sensation should return over weeks to months, but followup closely with your surgeon.The usual signs of the nerves regenerating and neuropraxia
resolving is itching, followed by a burning sensation and then
occasional sharp, shock-like pains. These will be normal to experience,
and actually a promising sign. Usually, normal sensation returns, but
is is also possible to have decreased sensation or even increased
sensation to the areas affected. Re-educating nerves postoperatively is
often helpful and will allow proper instruction for the affected
sensory nerves - methods include using different textures to the
affected areas when showering, bathing, applying lotion, etc. If
bothersome, there are some medications that may be helpful, including
Neurontin for pain for hypersensitivity. You can try various textures
such as washcloths, loofahs, cotton sheets, etc. Massaging the areas is
also beneficial for the incision to make the finest scar possible. The
last place to regain the sensation will be directly adjacent to the
incision/scar as the nerves will make its way from the periphery to this
location. If continual pain arises, evaluation is warranted. After
ruling out other causes, one rare explanation may be that a neuroma has
developed and may require surgical excision. This is very unlikely
unless a large sensory nerve has been transected inadvertently during
the procedure. Hope that this helps! Best wishes!

The sensibility to you chin should come back in time although 4 weeks starts to create some anxiety.  If the nerve was cut (and it should not have been) repair will be necessary and it will take a long time to recover.  I strongly doubt this is the case.  Numbness from handling the nerve is common and may take a number of weeks but usually is just a few days.  If the implant is putting pressure on the nerve, it will need to be repositioned if sensibility is to return.