Identifying marginal adaptation discrepancies of lithium disilicate crowns using seven different vertical X-ray angulations.

The radiographic interpretation of the marginal discrepancies of lithium disilicate crowns is significantly affected by the dimension of the marginal discrepancy. Specifically on premolar crowns, it is significantly affected by different vertical angulations of the X-ray beam. When evaluating marginal discrepancy on lithium disilicate crowns radiographically, vertical beam angulation within ±10° to the cemento-enamel junctionCEJ plane is recommended.