Objectives: The objective of this clinical trial was to assess long-term durability of complete crowns fabricated chairside from bis-acrylic composite resin materials.
Methods: Five patients in need of two single crowns were selected. After approval of the ethics committee and informed consent, diagnostic casts were fabricated and diagnostic waxings were prepared. After caries removal, the selected teeth were restored with low-shrinking composite resin (P-90, 3MESPE). Teeth that were endodontically treated received a fiber post (RelyX Fiber Post, 3MESPE) followed by core reconstruction (P-90, 3MESPE). Both teeth for each patient were prepared for complete crowns and immediate complete crowns were fabricated with two bis-acrylic composite resin materials (1) Protemp 4 (3MESPE) and (2) Luxatemp Fluorescence (DMG). Crowns were cemented with self-adhesive cement (RelyX Unicem Clicker, 3MESPE). Recalls were made at 1, 3, 6 and 12 months. Impressions were made with a poly-vinyl siloxane impression material (Express XT, 3MESPE) to evaluate surface aspects of the crowns under scanning electron microscopy. Marginal fit was evaluated with bite-wing radiographs. Gingival health was evaluated with probing and bleeding indexes. Material properties were evaluated clinically with photographic documentation. Finally, overall clinical handling and patient satisfaction were documented at each recall.
Results: There were no recorded failures after 12 months. Overall satisfaction was very high. Wear was noted in 2 Luxatemp crowns. After 1 month, loss of surface luster was noted for all Luxatemp crowns.
Conclusions: Within the limitations of this study, it can be concluded that after 12 months the direct technique can be viable when using bis-acrylic composite resin materials. Protemp 4 material performed better with regard to wear and maintenance of surface luster. (This study was supported by 3MESPE, Seefeld, Germany.)