Journal of Dental Research, Vol 64, 6-11, Copyright © 1985 by International & American Associations for Dental Research Online Journals
Evaluation of 2-phosphono-butane 1,2,4 tricarboxylate as a crystal growth inhibitor in vitro and in vivo
A. Gaffar and E. C. Moreno
The inhibitory activity of 2-phosphono-butane 1,2,4 tricarboxylic acid
(PBTA) in the formation of hydroxyapatite (HA) was studied in vitro and in
vivo. PBTA, at 4 ppm, inhibited the spontaneous formation of HA in vitro
from a supersaturated solution. PBTA, at 2 ppm, completely inhibited the
crystal growth of HA; at lower concentrations, a direct relationship was
found between the reduction of the initial precipitation rates and PBTA
concentrations in the solution. The effects of PBTA on human dental enamel
in vitro were also evaluated at pH 5.0 and 7.5. Equimolar levels of EDTA
served as the controls. In comparison with EDTA, the dissolution of enamel
induced by PBTA was negligible. One percent solution of PBTA was evaluated
in a rat calculus assay. In comparison with a placebo solution, it
significantly (p = 0.05) reduced calculus formation when applied topically.
It was also tested against calculus formation in beagle dogs. A topical
application once a day of a 1% solution at pH 7.0 reduced calculus
formation by 84% for 16 weeks. Analysis of these data suggests that the
agent effectively reduces calculus formation in vivo.
