In this study, the effect of enamel etching resulting in permanently l
ost enamel was investigated. Phosphoric acid and maleic acid were used
as etchants. Also the etch duration was varied. The results of the st
udy show that phosphoric acid removed significantly more enamel than m
aleic acid. The relationship found between the loss of enamel and the
etch duration suggested that a diffusion controlled mechanism plays a
role in the case of both acids. Morphological information obtained by
scanning electron microscopy indicated that the surface structure resu
lting from etching with phosphoric acid and maleic acid is similar.