Journal of Dental Research, Vol 73, 644-651, Copyright © 1994 by International & American Associations for Dental Research Online Journals
Proton probe and acid etching for determining fluoride profiles in porous porcine enamel
A. Richards, G. E. Coote and E. I. Pearce
Department of Oral Anatomy, Dental Pathology and Operative Dentistry, Royal Dental College, Faculty of Health Sciences, Aarhus University, Denmark.
An acid-etch technique and a proton probe were used to obtain profiles of
changes in fluoride concentrations across enamel of 24 normal and 24
fluorotic porcine teeth. Polished and unpolished sections were used for
probe measurements, and blocks of enamel cut from tissue adjacent to the
sections were used for acid etching. Additional blocks were etched with
acid containing dye to study penetration of acid beyond the sampling sites.
Probe-derived values were characterized by wide fluctuations. They were
also higher than acid-etch values, and this difference was reduced but not
eliminated by polishing the sections prior to scanning. Profiles obtained
with the two methods followed a parallel course in fluorotic and normal
enamel. Thus, errors due to chemical estimations of enamel depth with the
etch technique were not demonstrated, although penetration of acid deep to
the surface of the porous fluorotic enamel was observed. Further
development of the precision of the probe method is required to optimize
the unique advantage provided by the potential accuracy, speed of data
collection, and spatial resolution of this method.
