Evaluation of the diffusion of triamcinolone and demeclocycline through the dentinal tubules and apical foramen: A mass spectrometry study

AIM: The aim of this study was to investigate the diffusion of triamcinolone and demeclocycline from an endodontic paste when used unmodified, versus when combined in equal parts with a calcium hydroxide paste, in terms of diffusion through the dentinal tubules versus through the apical foramen. METHODOLOGY: Medicaments were placed in endodontically prepared roots that were kept in vials of Milli-Q water. The five experimental groups in the study were (1) control – no medicament, (2) medicament containing triamcinolone and demeclocycline (T&D) and occluded apex, (3) T&D paste and patent apex, (4) T&D + calcium hydroxide (Ca(OH)(2)) occluded apex, and (5) T&D + Ca(OH)(2) and patent apex. The triamcinolone and demeclocycline concentrations were measured with solid-phase extraction and ultra-high performance liquid chromatography–mass spectrometry, after 1, 3, 8, and 24 h, and after 1 week. RESULTS: Most of the triamcinolone and demeclocycline diffused through the apical foramen, with sparse diffusion through the dentinal tubules. The T&D paste mixed with Ca(OH)(2) in equal amounts showed greater than the expected 50% reduction in the diffusion of triamcinolone and demeclocycline from mass dilution alone (89% and 80%, respectively). CONCLUSIONS: These results stress the importance of maintaining apical patency, for allowing diffusion of active components of the drugs to target tissues in the periapical environment.