Influence of vision on the evaluation of marginal discrepancies in restorations

This study investigated the influence of visual inspection in the detection and discrimination between principle types of marginal discrepancies in restorations. Using devices simulating vertical steps, horizontal gaps and the combination of a vertical step and horizontal gap at the margin of a restoration, and explorers with four different tip diameters, 10 experienced dental faculty members were asked to identify discrepancies and the boundary between Alpha (excellent) and Bravo (clinically acceptable) marginal adaptation ratings under three different visual conditions--with and without visual inspection and visual inspection aided with binocular loupes. A significant correlation was found to exist between explorer tip diameter and the Alpha/Bravo boundary for horizontal gaps, but not for vertical steps. There was no significant difference in the detection of the Alpha/Bravo boundary for the three visual conditions. It was concluded that visual inspection aided and unaided with loupes had no significant effect on the evaluation of simulated marginal discrepancies. These findings highlight the importance of the traditional dental explorer, in the absence of a more discriminatory devices in the assessment of marginal discrepancies in restorations.