13 to 90.09 μm. The marginal and internal discrepancies of the tested materials were considered clinically acceptable.

To evaluate the physical and mechanical properties of maxillofacial silicone elastomers following the incorporation of a specific particle size and concentration of nano-titanium dioxide (TiO

) and nano-zinc oxide (ZnO).

Nano-TiO

and nano-ZnO of 20-nm and 40-nm particle sizes and in 1% and 2% concentrations were chosen. Silicone elastomer samples were prepared according to the manufacturer’s recommendations. The nano-oxides were incorporated via hand spatulation. The samples were subsequently tested for hardness and color stability and were then subjected to aging in an aging chamber for 1,008 hours, following which they were again evaluated for hardness, color stability, and surface roughness.

A significant change was noted in the physical and mechanical properties post-aging in all the groups. The samples with nano-TiO

of 40-nm particle size/2% concentration had the highest hardness, while color stability and surface roughness were higher in samples with nano-TiO

of 20-nm particle size/1% and 2% concentrations, respectively.

It can be concluded that 20-nm nano-TiO

particles best maintain the ideal properties of maxillofacial silicone elastomers and can potentially be used as alternative opacifiers when mixed with A-2186 maxillofacial silicone elastomers.

It can be concluded that 20-nm nano-TiO2 particles best maintain the ideal properties of maxillofacial silicone elastomers and can potentially be used as alternative opacifiers when mixed with A-2186 maxillofacial silicone elastomers.

To investigate the impact of high-speed sintering and artificial aging on the fracture load of three-unit zirconia fixed dental prostheses (FDPs).

Three-unit FDPs manufactured from 3Y-TZP (Ceramill Zolid, Amann Girrbach) and 4Y-TZP (Ceramill Zolid HT+, Amann Girrbach; N = 128, n = 64/group) were sintered at 1,580°C (high-speed sintering) or at 1,450°C (control group; n = 32/subgroup). Specimens were bonded to steel abutment models using Multilink Automix (Ivoclar Vivadent), and fracture load was examined without (n = 16/subgroup) and with artificial aging (6,000 thermocycles [5°C/55°C] and 1,200,000 chewing cycles [50 N]; n = 16/subgroup). Univariate analysis of variance, unpaired t test, and Weibull modulus were computed (P < .05).

Sintering protocol (P = .944), artificial aging (P = .630), and zirconia material (P = .445) did not show an influence on the fracture load of three-unit FDPs. High-speed sintering led to superior Weibull modulus results for artificially aged 4Y-TZP specimens, while all other groups showed values in the same range.

The present study shows promising results for the novel high-speed sintering protocol, as it led to comparable fracture load and similar, or even superior, Weibull modulus results compared to the control group. The 4Y-TZP material presented fracture load results similar to the tried-and-tested 3Y-TZP. PP2 price Artificial aging did not influence zirconia’s resistance to fracture for either 3Y-TZP or 4Y-TZP.

The present study shows promising results for the novel high-speed sintering protocol, as it led to comparable fracture load and similar, or even superior, Weibull modulus results compared to the control group. The 4Y-TZP material presented fracture load results similar to the tried-and-tested 3Y-TZP. Artificial aging did not influence zirconia’s resistance to fracture for either 3Y-TZP or 4Y-TZP.

To evaluate the 2-year performance of definitive implant- or tooth-supported three-unit fixed dental prostheses made of zirconia-reinforced lithium silicate placed to restore premolars and molars in clinical cases of partial edentulism.

All patients received a three-unit fixed restoration made of monolithic, hot-pressed, zirconia-reinforced lithium silicate glass-ceramic. The restoration was cemented to two natural teeth or attached to two 3.5- or 4.5-mm-diameter square threaded, grit-blasted, acid-etched integrated implants with a Morse taper connection. Peri-implant pocket depth and bone and soft tissue remodeling were recorded for 2 years at each follow-up visit. Esthetic, functional, and biologic United States Public Health Services (USPHS) parameters modified by the World Dental Federation study design were assessed yearly until the final follow-up appointment. At the time of placement of the definitive restorations and at the 2-year follow-up visit, the opposing dentitions were identified by type ofe 2-year results of this report will be studied more in depth in ongoing long-term research.

Implant-supported or tooth-supported three-unit fixed dental prostheses made of zirconia-reinforced lithium silicate can be used to successfully restore cases of posterior partial edentulism. The 2-year results of this report will be studied more in depth in ongoing long-term research.

To investigate the effect of training on scanning accuracy of complete arch scans (CAS) performed by first-time users, with a distinction made between specific training (repeated performance of CAS) and nonspecific training (simple use of an intraoral optical scanner for a sextant scan in the context of a CAD/CAM teaching module).

A total of 36 students with no experience in intraoral scanning were randomized into three groups (n = 12 per group) according to the number of CAS sessions three sessions (3S), two sessions (2S), and one session (1S). Each student had to perform 10 CAS per scanning session. Sessions were scheduled at T

, T

, and T

for group 3S; at T

and T

for group 2S; and at T

for group 1S. Before the final scanning session in each group (ie, the first scanning session in group 1S), the students completed a CAD/CAM teaching module, which included fabrication of a monolithic crown in a fully digital chairside workflow.

In all groups, repeated CAS resulted in improved scanning accuracy. Participation in the CAD/CAM module had a positive effect on initial accuracy for CAS. Mean absolute deviations in cross-arch distance were 84 μm (T

), 68 μm (T

), and 63 μm (T

) for group 3S; 79 μm (T

) and 61 μm (T

) for group 2S; and 67 μm (T

) for group 1S.

To perform CAS with the best possible accuracy, specific training is highly recommended. In addition, nonspecific training leads to an improvement in initial scanning accuracy.

To perform CAS with the best possible accuracy, specific training is highly recommended. In addition, nonspecific training leads to an improvement in initial scanning accuracy.