I think it depends on the tooth and the infection. 6 months ago DD, 9, had an abscess on her baby tooth, and we spoke to several dentists, and they were all telling us to pull the tooth out immediately! The tone was implying that we were negligent parents for allowing an infection near the brain and what not. It was one of the back molars, and the new tooth is supposed to come between the ages of 9 and 12, so they were also recommending a spacer. We panicked and pulled it out. It was awful for DD, because she is very sensitive...
Then DD had another abcsess. Another back tooth, on the other side. One dentist recommended an immediate extraction again...Then we saw an older dentist, and he said he'd rather monitor the abcsess, and as long as it drained into her mouth and wasn't painful, then it is better to keep it than to have a spacer.
Yesterday we saw yet another dentist, with who we will probably stick. She's had this abscess (no pain) on and off for several months now. Considering that DD will not tolerate a spacer, and the new tooth is not due until 1-3 years, he somewhat reluctantly agreed to keep the tooth and monitor closely. When we questioned him about negative consequences, he admitted that there weren't as many. Yes, a systemic infection was possible, but a very remote possibility, and not his worry. We've heard before that the bone density could be affected, thus making the new tooth weaker, but he wasn't concern at this point.
Now, if DD was a child like her friend, who had no issues with his tooth being pulled, and thought it was pretty cool, I would lean towards pulling out an infected tooth. But because she is so sensitive and anxious about it, I'm trying to find a good balance for us.
If there's less than a year befor the new tooth is expected, a spacer is unlikely to be needed.
Good luck...
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