Chemical and physical studies of enamel from human teeth. II. Specific gravity, nitrogen content, and hardness rating of discolored enamel.
D003743:Dental Enamel; D006244:Hardness; D006801:Humans; D009584:Nitrogen / Q000032:analysis*; D013046:Specific Gravity
D009584:Nitrogen
DENTAL ENAMEL; NITROGEN/determination