Welcome to just answer.
Yes a root canal therapy
can be performed on a crowned tooth,If a crowned tooth does require a root canal,it could be that the tooth has abscessed or that decay
has gotten underneath the crown and reached the pulp
of the tooth.
can make a hole through the crown, and patch it afterward,also a hole in the back of the crown can be drilled to get access to do the root canal.
Also,if the tooth is crowned a separate procedure called a post and core is often needed to build up the tooth on a previously treated root canaled tooth.
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Any antibiotic will need minimum 48 hours to get effective and it can vary among individuals,if you are uncomfortable and you are having pain
you can also take a painkiller along with the antibiotics.
You can take tablet Tylenol 650mg,thrice daily,it is an otc drug.
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To reduce the swelling and for the drainage of abscess
you can start rinsing frequently with hot salt water solution-- dissolve ½-teaspoon of salt in 8 ounces of water as hot as you can tolerate
without burning your mouth,and rinse for two minutes every four hours, this will provide you
Avoid eating, hot, spicy and hard food.
Donot brush hard or chew hard foods from that area
I hope this answers all your queries.
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