<s>[INST] Hello - Since having three crowns on my lower front teeth, I have been getting two light in yellow color pus filled blisters on my gum line, directly below the crowns.  I did not have these before.  I pop them and they return.  I am pretty sure this means an infection of some sort and I need to go to the doctor.  I am not running a fever.  Admittedly, my crowns were EXTREMELY sensitive at first - to the point I could not chew with them.  this lasted a few months.  They still get a little sensitive but I am able to use them better this last month plus or so.  I still cannot use them as "tools" - for example, pulling off foil from the top of a lid.  Thank you in advance. [/INST] Thanks for your query, I have gone through your query. the US filled swellings over the gums could be because of the collection of the puss secondary to tooth infection (periapical abscess). Consult an oral physician and take a radiograph to rule out the tooth infection. If there is tooth infection you have to get it treated with root canal treatment. The bridge has to be removed and then treated. You can take a course of antibiotics, but it is temporary solution. If you neglect then the teeth has to go for extraction. I hope my answer will help you. </s>