[Adherent surface treatment that improve the shear bond strength of calcium metaphosphate glass-ceramic (CMP)]

In this study we examined the shearing adhesive strength between a calcium metaphosphate glass-ceramic (CMP) and various luting materials. Two usual luting cement-zinc phosphate cement (Elite Cement 100), glass-ionomer cement (Fuji ionomer cement Type I) and three adhesive luting resin-Super Bond C & B, Panavia EX and a tentative luting resin were used as the material. We also examined the effect of three adherent surface treatments--50 microns Almina blasting, hydrofluoride etching, and sodium hydroxide etching--on the adhesive strength of the two adhesive resin, Panavia EX and the tentative luting resin, to CMP. The following conclusion were drawn: 1. The adhesive strength to CMP surface polished with #600 emery paper was higher in order of Super Bond C & B, a tentative luting resin, Panavia EX, Fuji ionomer cement Type I and Elite Cement 100. 2. Sodium hydroxide etching was the most effective for the adhesion between the adhesive luting resin and CMP among the above four adherent surface treatments. 3. Irrespective of the etching time, the stimulation of sodium hydroxide bath by supersonic waves gave an additional increase to the adhesive strength. 4. Under the stimulation by supersonic waves, increasing sodium hydroxide concentration tends to increase the adhesive strength, whereas it is little affected by the etching time within three minutes. The maximum was obtained with concentration in four or five normal (4 or 5 N) sodium hydroxide.