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This study demonstrates the potential of EGCG coating to enhance the surface properties of PEEK as dental implants. The combined piranha and EGCG modification approach shows promise for improved osseointegration, although further vivo research is necessary. Surface modification techniques hold the key to optimizing biomaterial performance, bridging the gap between laboratory findings and clinical implementation in dental implantology.
Background: Silicone elastomers are the main materials used nowadays in fabricating facial prosthesis, due to their high compatibility, chemical inertness, elasticity and ability to be colored by pigments. But many other properties need to be improved in order to have a better clinical performance like increasing tear strength, tensile strength and bonding to acrylic resin. So an increasing number of studies are performed each year trying to improve these properties, some studies concentrated on incorporating different types of nano oxide particles into the silicone matrix. \n \nAim of the study: The aim of this study was to investigate the effect of adding different concentrations of titanium silicate nano particles into silicone matrix on tear strength, tensile strength and hardness. \n \nMaterials and method: Depending on the results of a pilot study, 0.5% and 1% weight concentrations of titanium silicate nano filler were selected, as they had the most improvement in properties of the silicone material. The manufacturer’s instructions were followed in mixing and curing of the maxillofacial silicone material, and 90 specimens were prepared, the samples were divided into 3 groups according to the tests (tear strength, tensile strength and hardness), each group contains 30 samples, the groups were subdivided into three subgroups (A, B and C); group A is the control group with 0% of nano filler, while both B and C groups being experimental groups with 0.5% and 1% of nano filler respectively. The collected results of the study were analyzed statistically by using analysis of variance (one way ANOVA) and Post hoc tests. \n \nResults: For tear strength and tensile strength both experimental groups (0.5% and 1%) showed a highly significant increase in values compared to control groups, with the highest mean value being noticed in 0.5% group. While in shore A hardness test both experimental groups showed a highly significant increase in hardness compared to control group, with the highest mean value being noticed in 1% group. \n \nConclusion: The addition of 0.5% concentration of titanium silicate nano particles into silicone elastomer enhanced some of the material properties with a slight increase in hardness.
The results of this study suggest that the piranha solution can be an effective method for improving the surface characteristics of PEEK to be used in different dental applications, especially as a dental implant material, due to the increase in wettability and surface roughness.
Maintaining an ideal hardness value during the long term use of soft liner is very difficult, because soft liner material will lose some \nof its components and gain others, this will adversely affect its properties. The aim of the current study was to evaluate the effect \nof virgin coconut oil addition on the hardness of heat-cured acrylic based soft denture liner material. In addition, to investigate the \nwettability of the material after this incorporation. Both investigations were conducted at different periods of time. \nMaterial and method: one hundred eighty samples were prepared by the addition of 1.5% and 2.5% (by volume) of virgin coconut \noil into acrylic-based heat cured soft denture lining material. The study samples were divided into two groups (90 samples for \neach group) according to the conducted test; hardness and wettability tests. Then each group was further subdivided into three \nsubgroups (control 0%, 1.5% and 2.5%) according to the concentration of the incorporated coconut oil (n=10 samples for each \nsubgroup). Each group was assessed at different time intervals (1 day in distilled water, 14 and 30 days in artificial saliva), ten \nsamples were used for each time interval. Fourier transform infrared analysis was used to detect if there is any chemical reaction \nbetween soft lining material and coconut oil. \nResults: Shore A hardness test demonstrated a reduction in the mean value of hardness after adding 1.5% and 2.5% coconut \noil in comparison to the control group, this reduction was highly significant after 24 hours incubation in distilled water. The \nresults revealed a fluctuating behavior at different time intervals in which the values showed an increase followed by a decrease \nin the hardness after incubation in artificial saliva for both 2 and 4 weeks. Regarding the wettability test, the results revealed a \nreduction in the contact angle values after 24 hours and 2 weeks of incubation intervals, this reduction was highly significant for \nthe 1.5% group (p<0.01). While after 4 weeks of incubation, the mean values of contact angle of the experimental groups were \nincreased. Conclusion: Virgin coconut oil was successfully incorporated into the soft denture liner and revealed an improvement \nin the material softness and wettability.
The increasing adoption of digital light processing (DLP) three-dimensional (3D) printing in prosthodontics has enabled the rapid fabrication of denture bases with improved dimensional accuracy and reproducibility. However, the mechanical performance and surface characteristics of 3D-printed denture base resins remain inferior to those of conventional heat-polymerized polymethyl methacrylate (PMMA), limiting their long-term clinical reliability. This study aimed to investigate the effect of incorporating zinc oxide (ZnO) and samarium oxide (Sm<sub>2</sub>O<sub>3</sub>) nanoparticles, individually and as hybrid nanofiller systems, on the mechanical and wettability properties of a DLP 3D-printed denture base resin. ZnO and Sm<sub>2</sub>O<sub>3</sub> nanoparticles were incorporated into a photopolymerizable denture base resin at concentrations of 1 and 2 wt.%, producing seven experimental formulations, including a control group. A total of 280 specimens were fabricated using a DLP 3D printer and subjected to standardized post-processing. Nanoparticle dispersion and morphology were examined using field-emission scanning electron microscopy (FE-SEM), while Fourier-transform infrared spectroscopy (FTIR) was employed to assess possible chemical interactions between the nanofillers and the polymer matrix. Mechanical performance was evaluated through impact strength, transverse strength, and flexural strength tests, and surface wettability was assessed using static water contact angle measurements. Statistical analysis was conducted using one-way ANOVA followed by Tukey's post hoc test (α = 0.05). The results demonstrated that all nanoparticle-reinforced groups exhibited significantly enhanced mechanical properties compared with the unmodified control resin. The incorporation of 1 wt.% nanofillers yielded the most pronounced improvements, with the 1 wt.% ZnO group achieving the highest transverse strength and the 1 wt.% ZnO-Sm<sub>2</sub>O<sub>3</sub> hybrid group exhibiting the maximum flexural strength. Increasing the nanofiller concentration to 2 wt.% resulted in partial reductions in impact and flexural strength, which were attributed to nanoparticle agglomeration and increased light scattering during photopolymerization. FTIR analysis revealed no evidence of chemical bonding between the resin matrix and the nanofillers, indicating that the observed enhancements were primarily governed by physical reinforcement mechanisms. Wettability analysis showed that Sm<sub>2</sub>O<sub>3</sub>-containing formulations significantly reduced the water contact angle, indicating increased surface hydrophilicity, whereas ZnO incorporation produced more hydrophobic surfaces. Within the limitations of this in vitro study, the findings suggest that low-concentration incorporation of ZnO and Sm<sub>2</sub>O<sub>3</sub> nanoparticles represents an effective strategy to enhance the mechanical integrity and tailor the surface properties of DLP 3D-printed denture base resins. These results suggest potential clinical relevance of nanoparticle-reinforced printed denture bases, emphasizing the importance of optimized filler loading to avoid agglomeration-induced performance degradation.
