Rachel Weaver’s original Dental formula in a glycohol base is a household favorite for many. Black walnut hull is the star of this popular formula for supporting healthy teeth. To use, dilute Dental Formula in a small amount of water, swish around teeth, and swallow. May also be taken without water. This can be done several times a day. Use 4-8 weeks and then take a 1-2 week break. Calc Tea or Herb Calc can be taken along with Dental Formula or during the in-between weeks. 2 fl. oz.