The RCT before/after pics were most helpful, thank you. So it looks that despite the RCT being redone to a good level, the infection did not fully clear up - this happens rarely, and usually with infections that have been untreated for a long time.
The issues with pregnancy are:
- The foetus is most vulnerable during the first 12 weeks. During this period of time, all of the major organs and body systems are forming and can be damaged if the foetus is exposed to drugs, infectious agents, radiation, certain medications, tobacco and toxic substances. The actual risk depends on the type of drug and amounts, the level of radiation and where it is directed, ... So, although emergency treatment sometimes just has to be done at this stage, everyone avoids elective treatment.
- 2nd trimester is better as bub is more developed.
- 3rd trimester is also safe but more uncomfortable for Mum for long procedures, and ideally Mum should lie on left side to avoid pressure on inferior vena cava. That's a bit hard in a dental chair.
- The fact that you have a gumboil means that the pus is bursting out (like a pimple) so the risk of developing a full-on facial swelling with a serious bacteraemia is very remote. On that basis you could wait till after bub is born.
- The main issue with dental treatment for preg Mums is the need for pain relief because you are limited in what you can take. So, simple fillings, even RCTs that are likely to cause minor post-op pain are fine. More major issues like removing impacted wisdom teeth will cause more post-op pain and should be avoided if possible.
- I don't think a redo will make this better; the root filling looks very good. I would raise a flap and do a simple periapical curettage. I had a similar case once that persisted after an RCT, and attach before and after images. I'd go back to the endodontist that did this and ask his/her opinion; I would be happy to do this in 2nd trimester and expect you to have manageable pain requiring minimal painkillers.
- I also attach a Preg Leaflet I give out to my patients with lots of info for you. I live in Australia so the contact numbers aren't relevant.
- I used to work in a Medical Specialist building and the obstetrician across the way used to often send me pregnant patients. Let me know what you do, and your experience, pls. Best wishes for the birth!

Thank you so much doctor for all the super helpful advices. And the leaflet is so great to have, I cannot thank you enough. Update is - I went to see an endo specialist today and he provided some similar medical advice as what you provided.
He told me that rather than extracting it now, he'd like to have me keep it, observe it till the baby is born, bc according to him, the chances of having bacteria get into bloodstream is slim. However, when we talked about next steps, he did mention if I start to feel pain, or it converts from chronical status to acute status, I can call him to schedule an appointment to extract it even during pregnancy.
The best case scenario as he suggested today is, finger crossed everything is all well till the baby is born, and after delivery, he suggested that I do an apical surgery with him as doctor you also suggested. He is suspicious that there might be a crack in this teeth and he said if he sees a crack during the surgery, he would pause it, end it and schedule another appointment with me to do implant.
I think for now that is what I am planning to do, following his (and your) guidance and again finger crossed, this tooth won't be naughty in the upcoming 6 months so baby is healthy and the delivery is smooth.
The surgery that you've done, it is very impressive, thanks for sharing before and after x-rays. Can absolutely see that tooth was healing after the surgery. It gives me more confidence to go to this option. But my endo specialist seems a bit conservative that he does not want to risk it even I am in my 2nd tremister now. His view is, nothing happened is a good thing and let us not trigger it.
I have follow up questions if doctor you have a few mins, about this endo specialist's suggestions, would you share some of your thoughts? I am open minded to welcome any advices.
Last quick question will be - as you mentioned, there is a gumboil in my gum so the odd of having bacteria to go to bloodstream and to further impact the baby can be slim. Will the gumboil progresses to an extent that it will leak (pup goes out)? It was a small gumboil three months ago, and now it developed to a bigger one as it shows in the picture. What is the next phase of a gumboil? I want to be prepared for what might happen so when it happens, I am not be panicked about it.
I am sorry for my late response. I am in the US and did not get a chance to write it in my morning time. Again I really appreciate it doctor for your valuable advice. Thanks again.