Five-year double-blind randomized clinical evaluation of a resin-modified glass ionomer and a polyacid-modified resin in noncarious cervical lesions

Purpose: The aim of this double-blind randomized study was to compare the clinical performance of a resin-modified glass ionomer (Vitremer, 3M) and a polyacid-modified resin (Dyract, Dentsply DeTrey) in noncarious Class V restorations after 5 years. Materials and Methods: Twelve patients, having at least one pair of equal-sized noncarious cervical lesions under occlusion and a mean age of 40 years (range 19 to 63 years; median 41), were enrolled in this study. A total of 32 restorations (16 with each material) were placed according to the manufacturers' instructions by two calibrated operators. Two other independent examiners evaluated the restorations at baseline and after 5 years according to the USPHS criteria. The assessment criteria were: retention, anatomical form, marginal adaptation and marginal discoloration, color match, surface texture, and secondary caries. Statistical analysis was conducted using Fisher's exact test (alpha = 0.05). Results: No secondary caries was detected with either material. The retention rate for Vitremer (93%) and for Dyract (78.5%) did not differ significantly (p > 0.05). Regarding anatomical form, only two restorations of each material were recorded as bravo. In terms of marginal adaptation, 38.5% of Dyract restorations were rated alpha and 61.5% bravo, while 84.6% of Vitremer restorations were rated alpha and only 15.4% bravo (p < 0.05). For marginal discoloration, 18.2% of Dyract restorations and 84.6% of Vitremer restorations were rated alpha, with the remaining rated bravo. 86% of Vitremer restorations were rated as bravo and 23% alpha for both surface texture and color match. All Dyract restorations were classified as alpha regarding surface texture, and only two Dyract restorations (18.2%) were classified as bravo in the color match item. Conclusion: The marginal adaptation of the RMGIC (Vitremer) was significantly better, the marginal discoloration lower, and the retention rate higher (though not significantly) than that of the PMRC (Dyract) after 5 years in situ. Dyract performed better in terms of surface texture and color match in noncarious Class V restorations after 5 years.