Cad Cam Sistemi ve Yüksek Isıda Presleme Yöntemi ile Üretilen Porselen İnleylerin Kenar Uyumu ve Kırılma Dayanıklılığı Açısından Değerlendirilmesi.

Abstract

Evaluation of Marginal Adaptation and Fracture Strength of Porcelain Inlays Produced by CAD/CAM systems and Hot-Pressed Technique. Hacettepe University Health Sciences Institute PhD Thesis in Restorative Dentistry, Ankara, 2015. The aim of this in vitro study was to evaluate marginal adaptation and fracture strength of porcelain inlays produced by a CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) system using different types of ceramic blocs and hot-pressing technique. 60 extracted human mandibular molars were divided randomly into 4 groups (n=15). 45 molars in three groups, received MOD (mesio-occlusal-distal) inlay preparations. Experimental grups were; Group 1: Intact teeth, Group 2: IPS e.max CAD (Ivoclar Vivadent, Schaan, Liechtenstein) blocs and Cerec Omnicam (Sirona Dental Systems, Bensheim, Germany), Group 3: Lava Ultimate (3M ESPE, Seefeld, Germany) blocs and Cerec Omnicam, Group 4: IPS Empress Esthetic (Ivoclar Vivadent, Schaan, Liechtenstein) ingots and hot-pressing technique. MOD restorations were obtained according to these groups. Marginal gap measurements were taken at 12 points (mesial 3, distal 3, occlusobuccal 3, occlusolingual 3) with a stereomicroscope and mean values were calculated. Restorations were semented with Variolink N (Ivoclar Vivadent, Schaan, Liechtenstein) and stored in distilled water at 370C for 24 hours. All samples were subjected to thermocycling for 5000 cycles in water baths between 5◦C and 55◦C. The fracture strength of specimens was determined under compressive loads along the long axis of the restored teeth at a 0.5 mm/min crosshead speed until fracture. Fracture modes were determined and photographed. Statistical analyses were performed using one-way analysis of variance for fracture strength data and Kruskal-Wallis for marginal gap data (p=0.05). The mean marginal gap size of Group 2, Group 3 and Group 4 were 33,54 µm, 33,77 µm and 85,34 µm, respectively. Group 4 had statistically higher values than other groups. The fracture strength values were significantly higher in the intact teeth group (3959,00 ±1279,79 N), than those of restored groups (Group 2 (2408,00±607,97 N), Group 3 (2206,73±675,16) ve Group 4 (2879,53±897,30). İnlays fabricated using Cerec Omnicam demonstrated better marginal fit but fracture resistance values of different materials were similar.