Class II Amalgam Restorations, Glass-Ionomer Tunnel Restorations, and Caries Development on Adjacent Tooth Surfaces: A 3-Year Clinical Study

Eighteen caries-active adolescents, each having both a class II conventional amalgam (Dispersalloy) and a glass-ionomer (Ketac Silver) tunnel restoration of the same age placed on a contralateral tooth, were part of a 3-year clinical study. At the 1- and 2-year examinations all test restorations were assessed as acceptable in all patients. At the 3-year assessment three amalgam restorations failed due to recurrent caries, and one glass-ionomer restoration failed due to marginal ridge fracture. During the entire study period, the requirement of restorative therapy because of primary proximal caries was significantly reduced (p