The success of direct, indirect and CAD/CAM restorations on large sized cavities of vital teeth: A comparative clinical study

The aim of this study was to follow the clinical performance of direct, indirect resin composite and CAD/CAM resin nano-ceramic restorations in wide and deep lesions of posterior teeth during 30 months. Additionally, clinical success of indirect, direct and CAD/CAM restorations were compared with each other. 139 restorations in 82 patients were included to this study. For direct restorations, following the preparation of the cavities as usual, microhybrid resin composites (Gaenial posterior, GC Dental Products Corp., Aichi, Japan) were applied with the self-etch adhesive system (Clearfil SE Bond, Kuraray, NewYork, USA). After placement of the restorations, finishing and polishing procedures were completed. For indirect restorations, cavities were prepared according to mechanical cavity designs and stone moulds were obtained after the impression. Via those moulds, microhybrid resin composite restorations (TesceraTM Indirect Composite System, Bisco, Schaumburg, IL, USA) were tailored and polymerized under pressure/water/heat/light oven of the system TesceraTM ATLTM (Bisco, Schaumburg, IL, USA). Before placement of the restorations to the cavity, finishing and polishing procedures were completed. Obtained restorations which were completed in the laboratory were placed to the cavities by self-adhesive luting cement (RelyX U-200, 3M ESPE, St.Paul, MN, USA) after selective enamel etching. For another group computer aided design and computer aided manifacturing "CAD/CAM" resin nano-ceramic restorations, cavities were prepared according to mechanical cavity designs and digital impressions were made with intraoral camera (Bluecam, Sirona, Bensheim, Germany). The digital impressions transferred to the computer (Cerec System, Sirona, Bensheim, Germany) and were carried out of the design with the corresponding software (Cerec 4.2, Sirona, Bensheim, Germany) (computer aided design = CAD). The completely designed restorations were produced IV by using a chairside CAD/CAM technology (computer aided manifacturing = CAM) after resin nano-ceramic blocks (LavaTM Ultimate, 3M ESPE, St.Paul, MN, USA) were placed in the scraping unit attached to the system. Then fabricated restorations were luted using a self-adhesive resin cement with selective enamel conditioning. The clinical success of all restorations were evaluated with FDI Criteria as esthetically, biologically and functionally at baseline, 6, 12, 18, 24 and 30 months. While there was no significant difference biologically in restoration types at any time during the whole study (p>0.05); it was emphasized the superiority of indirect restorations in functional parameters and direct resin restorations in esthetic parameters were observed (p<0.05). In addition, when comparing all the criteria in esthetic, functional and biological parameters, the superiority of CAD / CAM restorations was observed in the first 18 months (p<0.05); after 18 months, this difference completely disappeared (p>0.05). Thus, at the end of the study, no difference was found between the types of restorations in overall clinical success (p>0.05). When restoration types are evaluated within themselves; the success of indirect restorations remained unchanged from beginning to end of the study. The performance of the direct and CAD / CAM restorations were changed at various control periods of this study. As a result, survival rate of this study was 95.6% for the indirect resin composite restorations, 89.4% for the direct resin restorations and 84.4% for CAD/CAM restorations at the end of the 30-month follow-up period of study. Keywords: Indirect Resin Composite; Direct Resin Composite; CAD/CAM Resin Nano-ceramic; Vital Teeth; Clinical Success