In situ microsampling technique for identification of elements of a restoration with exposed metal to identify potential allergens

Statement of problem. For clinical investigations of allergic reactions to dental materials, it is necessary to know the type of metal used in restora tions in the mouth of the patient. However, an intraoral method of sampling the dental alloy without removing the metal restoration has not yet been e stablished. Purpose. This study attempted to establish a clinically serviceable method for microsampling dental alloy. Material and methods. A piece of silicone sampling tube is held on the surf ace of the metal restoration. This surface was ground with a carbide bur th rough the sampling tube, and the ground metal particles were then recovered from the inner surface of the tube. The recovered sample was subjected to energy-dispersive x-ray microanalysis. The percentage recovery of ground al loy by this microsampling method, which was the ratio of the recovered weig ht of metal to the total weight of the metal ground, was evaluated using 3 mm diameter x 1 mm thick disk-shaped specimens of Ag-Au-Pd and Ni-Cr alloys . Results. Elemental analysis of the retrieved alloys identified the componen t elements in the alloy compositions. The percentage recovery by this micro sampling method was 75.0% for Ag-Au-Pd alloy and 69.9% for Ni-Cr alloy, res pectively Conclusions. The microsampling method demonstrated a relatively high percen tage recovery of the ground alloy particles. This microsampling method woul d be of great benefit clinically to patients who have allergic reactions to dental materials.