Hi and welcome to HCM,
Multiple extraction of the teeth is done only after evaluating the patients general health and well being , medical emergencies are considered like hypertension
. I hope you have already got all the tests done before taking the decision .
You did not mention your age here , but never the less if your teeth are mobile , extraction of upper and lower teeth done simultaneously will not be a problem for you and your dentist
. But if the extraction is traumatic ,wound healing may delay for some more time.
As you are going for multiple extraction , after the procedure the sockets will be closed in position by surgical sutures which helps fasten the healing. Sutures will be applied for 7 days along with a course of antibiotic and analgesics so dont worry you just have to follow the post extraction instructions properly given by your dentist. After 2 months depending on the formation of alveolar bone , prosthesis
can be made. take care.