Improving decision-making in restorations: evaluation of impressions and working casts.

The success of a crown greatly relies on its margin. An ill-fitted crown with an open margin will be susceptible to leakage and recurrent decay. If it remains undetected, it will eventually cause serious problems. This report looks at the finish line consistency of 73 "clinically acceptable" impressions made by dental students and working casts poured in the laboratory section. Findings show a number of possible inaccuracies in preparations, impressions, or a combination of both.