The aim of this investigation was to quantify the discolouration of tooth roots caused by various medicaments and sealers. The roots of extracted teeth were chemo-mechanically prepared and the smear layer removed. The roots were filled with either Multi-Cal (Pulpdent Corporation, Watertown, MA, USA), Ledermix (Lederle Laboratories, Wolfratshausen, Germany), 2% chlorhexadine acetate in polyethylene glycol (PEG), 5% clindamycin in PEG, PEG alone (as a vehicle control), sealers AH26 (De Trey Dentsply, Zurich, Switzerland), AH Plus (De Trey Dentsply), an experimental epoxy resin with zirconium dioxide (Millenium Chemicals, Rockingham, Western Australia) or Araldite (Selleys Pty Ltd, Sydney, Australia). The roots were maintained at 37°C in dark humid conditions and standardised images of the coronal surfaces recorded over 12 months. Ledermix caused the most darkening of the introduced medicaments, while calcium hydroxide and the materials in PEG did not cause darkening. AH26 caused more darkening than did the other sealers. It was concluded that the use of alternatives to Ledermix and AH26 should be considered when aesthetics are important.