56-month clinical performance of Class I and II resin composite restorations

Objective

This study evaluated the 56-month clinical performance of Class I and II resincomposite restorations. Filtek P60 was compared with Filtek Z250, which are bothindicated for posterior restorations but differ in terms of handlingcharacteristics. The null hypothesis tested was that there is no difference in theclinical performance of the two resin composites in posterior teeth.

Material and Methods

Thirty-three patients were treated by the same operator, who prepared 48 Class Iand 42 Class II cavities, which were restored with Single Bond/Filtek Z250 orSingle Bond/Filtek P60 restorative systems. Restorations were evaluated by twoindependent examiners at baseline and after 56 months, using the modified USPHScriteria. Data were analyzed statistically using Chi-square and Fisher''s Exacttests (a=0.05).

Results

After 56 months, 25 patients (31 Class I and 36 Class II) were analyzed. A 3%failure rate occurred due to secondary caries and excessive loss of anatomic formfor P60. For both restorative systems, there were no significant differences insecondary caries and postoperative sensitivity. However, significant changes wereobserved with respect to anatomic form, marginal discoloration, and marginaladaptation. Significant decreases in surface texture were observed exclusively forthe Z250 restorations.

Conclusions

Both restorative systems can be used for posterior restorations and can beexpected to perform well in the oral environment.