### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
can you answer dental questions?  i went to my dentist today.  it took 3 shots to numb my tooth for a crown on #30...on 2 of the 3 shots there was some strange sensation on my tongue or something that made me involuntarily cringe like pain...or a shock...never had that before...but he had NOT moved the needle at all so it wasnt the needle...then as we were about to start i could NOT close my right eye entirely...during the entire crown and another filling that cropped up in #29, my eye was tearing down my face and the back of my head...never stopped and i could never fully shut that eye on the same side as my shots.  what was that????

### output:

Thank you for your query in Chat Doctor forum. Usually one shot of 1.8 ml (1 cartridge) of local anesthesia(lidocaine) is enough to numb a tooth for crown reduction. Of course, if it is delivered properly. In some case of rare inflammatory situation little more amount injection may be required. The rate of local absorption may vary a little from person to person. So some time should be given after injection before checking the numbness. Fear or apprehension may lead to lowering pain threshold that is feeling of more pain psychologically. And the patient asks for repeated injection. It seems while giving 2nd injection your dentist missed the angle of the needle and pushed the needle little deeper which touched your facial nerve, and you felt an electric shock like feeling, and as the injection poured near facial nerve you had temporary facial muscle paralysis which prevents you from closing eyes and tears Chat Doctor.  Nothing to worry about that. This type of incident sometimes happens in a dental procedure. The eye and facial muscle comes back to normal state as soon as the action of injection is gone, roughly after 1 to 2 hours. Hope I am able to explain your query.