RCT in milk tooth depends upon which tooth the problem is. If the pain is in molars than yes, it is advisable to have RCT as permanent molars usually erupt at the age of 12 and extracting temporary molar at this age will leave a gap and may cause eruption problems by causing adjacent teeth to migrate into the empty space. In such cases your child mild require a space maintainer post extraction.
Now if the RCT is in anterior milk teeth, than go for extraction as permanent teeth will appear.
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