fireÂ·bomb (fÄ«râ²bÅmâ²) n. A bomb used to start a fire; an incendiary bomb. v. fireÂ·bombed, fireÂ·bombÂ·ing, fireÂ·bombs v.tr. To attack (a target) with a firebomb. v.intr. To launch an attack against a target, using a firebomb. fireâ²bombâ²er n. firebomb (ËfaÉªÉËbÉm) n (Firearms, Gunnery, Ordnance & Artillery) another name for incendiary 6. vb (tr) to attack with incendiary bombs. ËfireËbomber n. fireâ¢bomb (ËfaÉª É rËbÉm) n. 1. an explosive device with incendiary effects. v.t. 2.
Gum discoloration of this type is called an amalgam tattoo, which is caused when tiny pieces from a filling or cap wedge themselves into the gums. This issue often looks like a blue or black tattoo in the mouth, and it too is harmless. Smoking, certain medications such as minocycline, antimalarial agents, or tricyclic antidepressants, or metal-based crowns or fillings may also cause gum discoloration.
Caries can also attack the roots of teeth should they become exposed by gum recession. This is more common in older adults. Dental caries is caused by the action of acids on the enamel surface. The acid is produced when sugars (mainly sucrose) in foods or drinks react with bacteria present in the dental biofilm (plaque) on the tooth surface.