Brief Answer:
infection/complications,restoration/extraction

Detailed Answer:
Hi,

Thanks for your query, I have gone through your query.
As far as the bad teeth in your mouth is concerned, these teeth can get infected if they are not treated or extracted. These can result in formation of abscess, cyst or it can extend to involve bone resulting in osteomyelitis. These infections can cause pain, swelling, limited mouth opening and bad breath.
In order to prevent all these complications, If i am your treating doctor, I would suggest you to go for either restoration of the teeth, if sufficient tooth structure and bone support is available, if not the teeth has to be removed.
Regarding your exposed fillings, these exposed fillings can be re restored by silver amalgam or tooth color composite material if the decay is not involving the pulp. If the decay has extended to involve pulp, then it has to be root canal treated and crown has to be placed.
I would like to suggest some radiographic investigations like OPG, after seeing the OPG, I can clearly tell you, which all teeth can be restored or extracted.
Get a OPG done and upload the images.
I hope my answer will help you, take care.
If any queries are there, reply me back.

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