Dissolution of artificial (natural) stones in a standard model: first results.

In studying the dissolution of stones in vitro, the advantage of artificial stones in comparison to natural stones is that one can get substance-specific standardized and reproducible results. Our investigations were performed with artificial stones composed of natural material (calcium apatite). These stones were of spherical form and consisted of layers built up around a core. They were comparable to natural stones in their physical properties. Litholysis was performed in a special apparatus with continuous exposure to Suby G solution under standard conditions. Natural stones of the same chemical composition served as a reference. Statistical measurements were performed. By hardening of the artificial stones, it was possible to reach a dissolution comparable to natural stones composed of calcium apatite depending on the Suby G concentration (artificial 2.5 resp. 4.75 mg/h; natural 2.18 resp. 4.2 mg/h). For the first time, an artificial stone model has been created with reproducible behaviour in response to chemolitholysis and with properties of dissolution comparable to those of natural stones of identical chemical composition.