A Beck type magnetic pulser would probably do the job. 50 pulses or more and it would be gone. Miracle-Mineral-Supplement might work.
Silver might work if you take enough. Just depends on how much gets to the infection. You would have to drink 8 ounces a day at least. Without a machine it would be very expensive. Maybe the silver would absorb sublingually if held in the moth next to the tooth.
Since you don't want to get a root canal at all costs I would consider taking the Antibiotics . Also take some silver.