Rhinoliths are rare. They are calcareous concretions that are formed by the deposition of salts on an intranasal foreign body. The foreign body, which acts as the nucleus for encrustation, can be either endogenous or exogenous. Dessicated blood clots, ectopic teeth, and bone fragments are examples of endogenous matter. Exogenous materials include fruit seeds, plant material, beads, cotton wool, and dental impression material.
Although the pathogenesis remains unclear; a number of factors are thought to be involved in the formation of rhinoliths. These include entry and impaction of a foreign body in the nasal cavity, acute and chronic inflammation, obstruction and stagnation of nasal secretions, and precipitation of mineral salts. Development and progression are believed to take a number of years.
Most patients complain of purulent rhinorrhea and/or ipsilateral nasal obstruction. Other symptoms include fetor, epistaxis, sinusitis, headache and, in rare cases, epiphora. In some patients, rhinoliths are discovered incidentally.