Abstract
The aim of this study was to evaluate the common errors that may occur during crown and bridge construction. Four hund-red stone models were used in this study for fabrication of 265 bridges and 135 sin-gle crown. The total number of units was 1141. Four main parameters were evalua-ted for each stone model: General informa-tion about the case, the condition of the stone model, the type of impression mater-ial and the prepared abutment tooth.
The result of this study showed that 33.7% of the models were one unit and 48.7% of the models were 2–4 units and the remaining 17.5% of the models were more than five units, 8.7% of the models were without opposing arch. Alginate imp-ression materials were used in 95% of the cases and only 5% of the cases elastomeric impression material were used. The finish-ing line was absent in 19.7% of the cases. Enough tooth reduction was done in 61.3% of the cases and 16.3% of the cases showed too much tooth reduction while 22.4% of the cases the tooth reduction was not enough. In order to avoid these errors continuous education courses and journal club are highly recommended.
