Abstract: The method of etching a porcelain dental appliance insitu including the steps of contacting the porcelain with a buffered solution containing trace amounts of hydrogen fluoride and removing the solution after sufficient time has elapsed to etch the porcelain. Preferred solutions are buffered at a pH from about 2.0 to about 6.0 and most preferably from about 3.5 to about 4.5. Contact time of the solution with porcelain ranges from about five minutes to from about five to about thirty minutes or longer.The solution preferably contains an alkali metal fluoride dissolved in a weak acid. In a preferred embodiment, the solution contains about one to about three parts by weight of sodium fluoride dissolved in about 50 parts to about 150 parts by weight of dilute weak acid. The weak acid has a molarity of from about 0.05 molar to about 0.5 molar. The weak acid solution is buffered, if necessary, and has a pH of from about 2.0 to about 6.0 and preferably from about 3.5 to about 4.

Abstract: Dental cavity varnish compositions comprising a solution of nitrocellulose and toluene sulfonamide which wet and precisely conform to each "peak" and "valley" of the extensive microundercuts generated during cavity preparation. The varnish compositions are compatible with composite resin restorative materials.

Abstract: A non-carious erosion lesion of the cervical region of a tooth is restored without prior drilling preparation by etching the surface of the tooth, applying a primer thereto and filling said lesion with a composite material.