Cadmium Content of Gutta Percha Points

Gutta percha is used to obturate root canals during endodontic treatment.  In conjunction with sealants and cements, gutta percha is the most popular choice for solid core root filling.  However, some European reports have expressed concerns over potential health problems from high levels of cadmium in some gutta percha points (0.6% or 6,000 ppm).  Objective:  This study investigated the extent and level of possible cadmium in gutta percha points sold in the United States to assess any toxic potential.  Methods:  Ten brands of gutta percha points were evaluated.  For each brand ten points were digested in concentrated nitric and sulfuric acid, oxidized with potassium permanganate with excess permanganate reacted with hydroxyamine.  Samples were analyzed in duplicate by flame atomic absorption spectroscopy with a detection limit of 0.02 ppm.  Other heavy metals were also analyzed for comparison.  Results:  The cadmium content of the gutta percha brands were:

Cadmium content in all brands ranged from 2.8 to 10 ppm with a mean of 6.3 ± 3.2 (s.d.) ppm, which is equivalent to 0.10 µg Cd/ gutta percha point (range 0.03-0.30 µg).  If four points are used per root canal, the total cadmium will be about 0.4 µg.  Conclusions:  These data do not support health concerns for potential cadmium toxicity from gutta percha points, since the FDA allows up to 15 µg/g (ppm) of cadmium in food, and the average person in the U.S. consumes about 30 µg Cd/day.  The cadmium in finished gutta percha points is most likely a contaminant of one or more chemicals used in their manufacture.