Clinical behaviour of glass ionomer restorations in primary teeth

Objective: To compare a silver-reinforced glass ionomer material (cermet) w ith a resin-modified glass ionomer in minimal Class II preparations in prim ary teeth. Methods: Matched pairs of primary molars with approximal caries that requir ed operative treatment were used. Each cavity was fined with either Vitreme r or Ketac-Silver. The restorations were followed for at least 36 months an d examined annually using bitewing radiographs and clinical inspections. Im pressions were taken at each recall and models were examined microscopicall y. Results: After 36 months, one of the resin-modified glass ionomer (RMGI) re storations and 13 (26.5%) of the silver cermet restorations had failed. The RMGI failed because of secondary caries, while most of the failures of the silver cermet fillings were marginal defects alone or in combination with secondary caries. The median survival time (MST) for the silver cermet rest orations was 37 months. The RMGI restorations had a MST exceeding 42 months , but MST could not be calculated exactly because of the low failure rate d uring the study period. Conclusions: The resin-modified glass ionomer had the overall best performa nce of the two materials under comparison. The silver cermet material canno t be recommended for Class Il restorations in primary teeth. (C) 1999 Elsev ier Science Ltd. All rights reserved.