Cervical compomer restorations: The role of cavity etching in a 48-month clinical evaluation

Compomers are defined as polyacid-modified resin composites. They are suppo sed to combine the advantages of traditional glass-ionomer cements with res in composites. This study clinically evaluated a compomer in cervical cavities. Sixty cerv ical cavities in premolars and molars (24 with cervical caries and 36 with abrasions) randomly divided into two groups of 30 teeth (Group 1 and Group 2) were restored with Dyract (DeTrey-Dentsply, York, PA 17405-0872). The ca vities of Group 2 were etched for 30 seconds with orthophosphoric acid befo re compomer application, while the Group 1 cavities received no treatment. All the restorations were evaluated every six months, up to 48 months: char acteristics assessed according to USPHS-modified standards were retention, secondary caries, post-operative sensitivity, marginal adaptation and disco loration, color and wear. The Kaplan-Meier's survival analysis was performe d. In both groups, retention was high without any statistically significant di fference. No difference was found between the two groups for caries, post-o perative sensitivity and wear-that all had a low incidence. Color was not p erfectly matched, however, there was no statistically significant differenc e between the two groups. Marginal discoloration and marginal adaptation lo ss were significantly higher in non-etched group (p<0.05). Clinically relev ant failure required 17.2% of restorations in the non-etched group and 10% in the etched group to be replaced: this difference was not statistically s ignificant. Dyract has an acceptable clinical behavior when used in cervical cavities. Its marginal adaptation is enhanced by etching.