Evaluation of a new method for silver point removal.

A new device for removing silver points was evaluated. The instrument consists of a trepan bur to expose the end of the silver point and a hollow tube which fits over the exposed tip and is bonded to it with cyanoacrylate adhesive. Twenty groups with 10 extractors and silver points in each group were tested for adhesive strength with respect to overlap between extractor and silver point, snugness of fit, and setting time of the adhesive. The adhesive strengths were evaluated using the Instron Universal Testing Machine. Adhesive strengths of 2 to 5 kg were readily achieved, and such adhesion should be adequate under typical clinical conditions for silver point removal. The amount of overlap (in the range of 1 to 3 mm) and snugness of fit were significant in relation to adhesive strengths. A setting time of 5 min was adequate for maximum bonding, except when there was loose fit between the extractor and the silver point. Clinically, the device appears to be an effective method for silver point removal.