Proximal restorations and periodontal status.

The purpose of the present investigation was to evaluate the influence of overhanging marginal restorations on periodontal status and whether any such influence is modified by the patient's oral hygiene level and degree of radiographic attachment loss. The investigation was conducted as a retrospective study on a consecutive referral population. Periodontal pockets at proximal sites with marginal overhangs were significantly deeper (0.42 mm) compared to sites with metal restorations without overhangs. This difference was larger (0.62 mm) for sites with radiographic attachment loss < or = 6 mm, while no significant difference was found for sites with radiographic attachment loss > 6 mm. In patients with a mean radiographic attachment loss < or = 5 mm, an overhanging restoration margin was associated with a significantly increased loss of radiographic attachment (0.66 mm). It was concluded that the influence of a marginal overhang on pocket depth and radiographic attachment decreases with increasing loss of periodontal attachment in periodontitis-prone patients. The effect on pocket depth of a marginal overhang may act synergistically, potentiating the effect of poor oral hygiene.