apply the varnish thereto it should be appreciated that the varnish is of a suitable viscosity to allow movement through the brush and to be responsive to the applied squeezing pressure as will be discussed below the reduced viscosity of the varnish is achieved through certain ingredient choices the sodium fluoride is provided having an average particle size diameter of less than 50 micrometers microns further embodiments are provided where at least 80 of the particles have a diameter of less than 16 microns the fluoride is milled to obtain these particle sizes tight tolerances on the particle size provide for consistent fluoride release properties furthermore smaller fluoride particles decrease the likelihood of the particles settling out of solution additionally smaller fluoride particles provide for increased ease of re suspension thereof when some fluoride does happen to settle out in addition to formulations having 2 5 sodium fluoride embodiments are envisioned having greater amount of sodium fluoride such as 5 indeed formulations are envisioned having 1 7 5 fluoride by weight still further embodiments are envisioned where crystalline sodium fluoride is used where all or nearly all such as greater than 90 95 or 99 of the fluoride particles are less than 20 u00b1 2 microns in diameter still further in addition to using milling to obtain these particle sizes sifting or sieving is also or alternatively used as previously noted traditional varnishes have relied on pine tree resin base in order to remove the potential for pine allergy the present varnish uses the bleached dewaxed shellac lac this shellac is a non water soluble dewaxed bleached shellac this shellac when applied is colorless or clear such that no color is applied to.