Clinical evaluation of posterior composite restorations: the 10-year report

Abstract

Purpose: To summarize all clinically relevant data of a 10-year prospective evaluation of posterior glass-ionomer cement/composite restorations (Ketac Bond/Visio-Molar radiopaque).

Material and methods: For this study 194 hybrid composite fillings (115 Class I, 79 Class II) were applied in 73 adult patients. The exposed dentin was covered with glass-ionomer cement. The clinical evaluation was carried out at baseline, after 6 months and at 1-year intervals up to 10 years. The USPHS-compatible CPM Index was used with the C and P criteria presented here for anatomic form, color match, surface quality, wear, marginal integrity, marginal ledge, marginal discoloration, secondary caries, and clinical acceptability. Thermal and electrical sensitivity testing were recorded annually.

Results: At baseline, 194 restorations were rated. The drop-out of patients comprised 108 fillings after 10 years. During this time, 24 restorations could not be followed up because of new carious lesions at different sites and/or prosthodontic treatment (drop-out of teeth). Forty-six composite restorations were longitudinally controlled over 10 years, and 16 more fillings failed before the end of the study (3 filling fractures, 7 partial filling losses, 1 total filling loss, 5 cases of secondary caries). Only Class II composite restorations exhibited secondary caries (4 fillings after 7 years and 1 filling after 9 years). After 10 years, the correct anatomic form was preserved in 44 fillings, but all restorations showed rough surface and wear. The majority of restorations (26 fillings) was free of marginal discoloration, and the color match showed only 3 fillings being too dark. The marginal integrity was optimal at baseline and during the first year. During the second year a continuing degradation started and lasted until the end of the study. Thirteen restorations showed optimal marginal integrity after 10 years.

Conclusion: The USPHS-compatible CPM Index represents a sensitive rating system for long-term observation of posterior composite restorations. The early risk of failure is attributed to bulk fractures and partial loss of filling material. The longevity over 10 years is a maximum of 74.2%, and the very low secondary caries rate and the high percentage of correct anatomical form confirm the clinical safety of posterior composite restorations.