It can easily be, since there's logic to each part of the puzzle- especially with inflammation directly from the root canal/fistula having been in your bloodstream.
However, it depends upon how broad-spectrum the antibiotics are- if it's aimed at -all- types of infectious agents, it's going to make an easier playing field for reinfection in your gut and inflammation of the internal organs later.
I would say right now it is important to clear the dental infection and complete the course of antibiotics, and then heal the gum and gut.
There are many pieces of the puzzle. Was it a root canal that began with an external cavity, or an infection that started from the bloodstream? Could the infection have started to begin with because of a leaky gut and toxic habits/exposures?
Those are parts of the puzzle you'll need to explore yourself- But iodine is a good place to start researching, as it's one of those front-line defenders against infection across all epithelial barriers (gut, Blood-brain barrier, skin, gums, stomach, sexual organs, etc. )
Your gut flora is the basis for all your b-vitamins, fat-soluable vitamins, mineral absorbtion, etc.
Antibiotics are.. a mixed bag of tricks! However, at the moment I am glad you are seeing some relief. Use this time of a clear head to learn well, and make some simple plans for yourself. :)
And to repopulate your gut. Raw and fermented foods are a perfect way to get going on that. :-) Probiotics are not nearly as effective (from my experience).
Your liver will need help after the ibprofuen and with shunting out the toxins left over after the antibiotic circus too (since there'll be a lot of dead material to clean out). Some time in a sauna and in sea salt soaks (also rich in iodine) with some epsom salts/dead sea salts (high in magnesium) can help replenish your magnesium reserves, and sauna/sweating will help take out the trash so your liver doesn't have to. ;)
Here's the how and why of antibiotics being an issue: