Abstract
The aim was to investigate the marginal fit, internal adaptation and compressive strength of SLA provisionals (SLA) in comparison to CAD-CAM and conventional (CONV) interim fixed partial dentures (FPDs). Thirty interim FPDs were fabricated using CAD-CAM technology (CAD-CAM blocks Ceramill TEMP, PMMA), conventional molding technique (CONV) (TrimPlus, PMMA) and Stereolithography (SLA) method (Form 2, Formlabs, PMMA) (n = 10). Internal adaptation (occlusal, corona', middle and cervical) and marginal integrity (inner and outer edge) was assessed using micro-computerized tomography (Micro-CT). The failure and compressive strength was assessed by application of a static load at a crosshead speed of 1 mm/min until fracture. Data was analysed using ANOVA and multiple comparisons test. The maximum and minimum marginal mis-fit was for CONV (283.3 +/- 98.6 nm) and CAD-CAM (68.2 +/- 18.1 mu m) groups. CAD-CAM (68.2 +/- 18.1 mu m) and SLA (84.7 +/- 27.5 mu m) provisionals showed comparable marginal mis-fit (p > 0.05). The mean failure load was significantly higher (p < 0.05) in CAD-CAM (687.86 +/- 46.72 N), compared to SLA (534.8 +/- 46.1 N) and CONV (492.7 +/- 61.8 N) samples. Compressive strength for CAD-CAM (2.44 +/- 0.27 MPa) samples was significantly higher (p < 0.05) than SLA (1.80 +/- 0.15 MPa) and CONV (1.65 +/- 0.20 MPa) groups. Marginal fit and internal adaptation of SLA printed FPDs was comparable to CAD-CAM interims. Compressive strength of the SLA interims FPDs can withstand intra-oral loads.