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The results of the study indicate that it is possible to create an equally smooth surface for chairside CAD/CAM resilient materials compared with milled ceramics using several finishing and polishing techniques. In addition, both polishing techniques resulted in smoother ceramic surfaces when compared to glazed ceramic surfaces. The polished surface of the ceramic material was smoother than the glazed ceramic surface.

Provisional crowns fabricated from SNAP, Protemp Garant, and Integrity exhibited similarly low marginal discrepancy. SNAP, Luxatemp Solar, and Integrity did not demonstrate a clinically detectable change in shade after 1 week in a staining solution.

The use of immediate implants was a predictable surgical approach (96% survival rate), and the level of placement did not influence horizontal and vertical bone and soft tissue changes. This study suggests that a thick facial plate, small gaps, and premolar sites were more favorable for successful implant clinical outcomes in immediate implant placement.

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All‐ceramic restorations have become an attractive alternative to porcelain‐fused‐to‐metal crowns, but their strength is still an important issue. The purpose of this study was to compare the in vitro fracture resistance of three all‐ceramic systems: IPS Empress, In‐Ceram, and Procera AllCeram. Thirty dies were replicated from a master die using high filler resin with a modulus of elasticity similar to dentin. Ten cores each of In‐Ceram and Procera were fabricated to a thickness of 0.5 mm. The remaining porcelain was applied using a sculpting device to produce a crown with a final thickness of 1.0 mm axially and 2.5 mm occlusally. Ten IPS Empress crowns were waxed to the same dimensions and were pressed by the manufacturer. The internal surfaces of all the crowns were etched and silanated prior to cementation with a resin cement (Panavia 21). The cemented samples were loaded in an Instron machine until fracture. The mean fracture loads were: IPS Empress, 222.45 (±49) kg; In‐Ceram, 218.8 (±36) kg; Procera AllCeram, 194.20 (±37) kg. Tukey's test showed no statistically significant differences among the three all‐ceramic systems at p < .05.

Statistically significant differences were found for different CAD/CAM materials if the CAM procedure was identical. Within the limitations of this study, the choice of CAD/CAM material may influence the fitting accuracy of CAD/CAM-fabricated restorations.

This study evaluated differences in surface roughness of a microhybrid (Gradia™ Direct, GC America) and a nanofil (Filtek™ Supreme, 3M™ ESPE™) composite using four polishing systems: PoGo™/Enhance ® (DENTSPLY/Caulk), Sof-Lex™ (3MTM ESPE™), Astropol ® (Ivoclar Vivadent), and Optidisc™ (KerrHawe). Methods and Materials: An aluminum mold was used to prepare 2 X 60 composite disks (10 mm X 2 mm). Composite was packed into the mold, placed between two glass slabs, and polymerized for 40 seconds from the top and bottom surfaces. Specimens were finished to a standard rough surface using Moore's disks with six brushing strokes. Specimens were rinsed and stored in artificial saliva in individual plastic bags at 36°C for 24 hours prior to testing. Specimens were randomly assigned to one of the four polishing systems and were polished for 30 seconds (10 seconds per grit) with brushing strokes according to the manufacturer's instructions. Mean surface roughness (Ra) was recorded with a surface-analyzer 24 hours after storage in artificial saliva, both before and after polishing. Means were analyzed using two-way and one-way analysis of variance (ANOVA) and Tukey multiple comparison tests at p < 0.05. Results: There was a statistically significant difference for baseline measures between Filtek™ and Gradia™ (p=0.0338). For Filtek™, Sof-Lex™ provided a significantly smoother surface (Ra=0.80 ± 0.21) than Optidisc™ (Ra=0.93 ± 0.28), Astropol ® (Ra=1.