LHC likely created these particles which means we have single atoms that have been created and not full compounds.

Someone can correct me if I'm wrong, but the significance of this is mostly just further confirmation of the predictions of the standard model. The standard model says such particles should exist and now that we've created them, we've confirmed that they do indeed exist.

I don't think there's much practical application beyond further refinement of theoretical physics and ruling out other candidate theories.