A case of bone fluorosis of undetermined origin.

After predominant theories on the causes of fluorosis are described and remarks made about the metabolism of fluoride, an observation of bone fluorosis in a 64-year-old patient is reported. Because, despite painstaking research, none of the known causes of bone fluorosis could be found in our patient, a new pathomechanism is being offered for discussion, i.e., increased renal or intestinal absorption or an increase of fluoride deposited in the bone; i.e., an inborn or acquired error of fluoride metabolism. We recently observed a similar case with none of the well-known origins.