http://www.theguardian.com/society/2014/jun/16/fillings-dentists-tooth-decay-...

another mention from the Synergy site:
Dr. Tennant works closely with dentists to incorporate the Biomodulator and Transducer for natural healing of the teeth and gums. Using a combination of Raw Materials, Bentonite Clay and Burch Oil in paste around the teeth and gums then beaming the Biotransducer in Ten-8 mode on highest power 5-10 minutes for several sessions, has shown amazing results in natural teeth healing. Further research around the world is providing evidence that increasing voltage helps the body repair itself.