• endodontics;
  • diffusion;
  • therapeutics;
  • triamcinolone;
  • demeclocycline

Abstract The release of corticosteroid and antibiotic tracer molecules in Ledermix® paste from the pulp space to the external environment of human tooth roots was determined in vitro. For demeclocycline little of the tracer was released through the root apex; the great majority diffused through dentine. For triamcinolone about one-third of the tracer left the roots via the apical foramen; the remainder exited via the dentine. The rate of release of the tracers was highest during the first day, and declined exponentially with time thereafter. After 14 weeks, 98% of triamcinolone and 66% of demeclocycline had been released. In the teeth examined, diffusion rate was not related to the age or sex of the donor. Total release of the tracers was directly related to the area of contact between the paste and dentine. The data obtained are of immediate clinical relevance, and also add to our general understanding of drug dynamics in tooth roots.