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Statement of Problem: Soft liners are essential for denture wearers, which aids in the healing of soft tissue injuries caused by rough denture base surfaces. Silicone soft liners, while effective, can accumulate biofilm over time, necessitating enhancement., Purpose: This in vitro study aimed to assess the efficacy of silicone soft liners incorporating varying concentrations of cerium oxide nanoparticles., Materials and Methods: A stainless-steel die as per ISO standard 10139-2-2018 (35 × 6 mm), Using G*Power 3.0.10 software, 400 samples were prepared with 95 % confidence interval and 80 % power. Samples were divided into five groups: surface morphology (Group A), surface hardness (Group B), wettability (Group C), cytotoxicity (Group D), and antifungal property (Group E). Each group was subdivided based on cerium oxide nanoparticle concentrations. Samples were stored in artificial saliva until evaluation. Surface morphology was examined via scanning electron microscopy (SEM), surface hardness using Shore A Durometer, wettability by drop shape analysis, cytotoxicity via MTT assay, and antifungal properties using crystal violet staining.Data were assessed for normal distribution using Kolmogorov-Smirnov and Shapiro-Wilk tests., Results: SEM analysis showed optimal nanoparticle dispersion in Group A2(0.25 %) and A3 (0.5 %). Group B2 (0.25 %) exhibited the lowest mean surface hardness, decreasing from day 1 to day 30. Group C3 demonstrated the most hydrophobic surface across days. Group D2 exhibited the least cytotoxicity at all time intervals. Group E4 displayed the highest antifungal activity., Conclusion: Within study limitations, silicone soft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles exhibited superior properties in surface hardness and cytotoxicity. Optimal surface morphology and wettability were observed with 0.5 % concentration, while antifungal efficacy peaked at 1 %. These findings suggest clinical potential for treating damaged oral tissues., Clinical Implications: Soft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles may benefit patients with oral tissue abuse, offering enhanced therapeutic properties., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Aim: To compare the effect of polymerization of resin-modified glass ionomer cement and dual-cure resin cement on the crystalline structure and to correlate it clinically with postoperative sensitivity., Settings and Design: The evaluation of crystalline strain in the dentin slabs was done using Synchrotron X-ray diffraction. The post operative sensitivity was measured clinically using Schiff's sensitivity scale., Materials and Methods: A total of 44 extracted and noncarious premolars were collected. Dentin slabs of dimensions 2 mm × 2 mm × 1.5 mm were prepared from the buccal aspect of the extracted teeth. The dentin slabs were then divided into two groups, Group A dual-cured resin cement and Group B resin-modified glass ionomer cement was applied. The dentin slabs first underwent synchrotron X-ray diffraction before and after the application of cement. Forty-two patients who were undergoing complete metal fixed prostheses on vital posterior abutments were selected. In this, 21 vital abutments were included in each group. Tooth preparation and fabrication of complete metal prostheses were done in the conventional manner and cemented using the 2 luting cements in Groups A and B, respectively. Dentinal hypersensitivity was measured using Schiff 's scale, postcementation, after 1 week and 1 month., Statistical Analysis: Independent t-test was done for comparing the two cements in two cements in terms of lattice strain. Mann-Whitney U-test was done for comparing the cements with respect to dentinal hypersensitivity. Spearman's correlation coefficient was used for clinical correlation between dentinal hypersensitivity and crystalline strain., Results: The lattice strain generated in dual cure resin cement was higher than that in resin-modified glass ionomer cement and was statistically significant. Postcementation hypersensitivity was higher in dual-cured resin than resin-modified glass ionomer cement but was not statistically significant in the follow-up visits. Spearman's correlation coefficients did not reveal any significant clinical correlation between lattice strain and dentinal hypersensitivity., Conclusion: Dual cure resin cements generate greater lattice strain as compared to resin modified glass ionomer cements.

Aim: Aim of this study was to evaluate the effect of silver nanoparticles incorporated injection molded heat-cured polymethylmethacrylate resin on wettability, anti-fungal effect, flexural strength and colour stability in human saliva., Settings and Design: An In-Vitro study with In -Vivo parameter., Materials and Methods: Rectangular and circular stainless-steel dies were fabricated according to ISO standardization 20795-1:2018 and ADA specification number 12. A total of 144 samples were prepared and divided into 4 groups with thirty-six samples in each group. Each of the 4 groups were subdivided into 3 subgroups based on concentration of silver nanoparticles as 0% in subgroup A, 0.05% in subgroup B and 0.2% in subgroup C. Group 1 samples evaluated wettability, they were assessed at 0, 7, 90 and 180 days after immersing in human saliva using goniometer. Group 2 samples evaluated antifungal effect, they were assessed against Candida albicans in Muller hinton agar plate enriched with 2% glucose. Group 3 samples evaluated flexural strength, they were assessed by using universal testing machine. Group 4 samples evaluated colour stability, they were assessed using UV spectrophotometer at 0, 3 and 7 days after immersing in human saliva., Statistical Analysis Used: One-way ANOVA and Post- Hoc Tukey test were used to evaluate the significant differences in the mean values of the groups., Results: Subgroup C samples with 0.2% Ag nanoparticles had better wettability, maximum antifungal property, highest flexural strength and good colour stability followed by subgroup B and subgroup A samples., Conclusion: Injection molded denture base resin incorporated with 0.2% Ag nanoparticles could be used clinically as a denture base material for completely and partially edentulous patients., Competing Interests: None

Graph 1: Graph represents the dimensional stability of Group I and Group II samples.Image 1., Competing Interests: None declared., (© 2022 Craniofacial Research Foundation. Published by Elsevier B.V. All rights reserved.)

Statement of Problem: Poly-ether-ether-ketone (PEEK), a high-performance semi-crystalline thermoplastic polymer, has been employed to replace the metallic implant components in orthopedics. There were various studies performed in accordance to medical grade PEEK, but the relationship between titanium dioxide (TiO 2 )-coated PEEK, TiO 2 -blended PEEK, and untreated PEEK still remains complicated, even undefined., Purpose: The purpose of this study was to compare and quantify the osteogenic potential of untreated PEEK, TiO 2 -coated PEEK and TiO 2 -blended PEEK., Materials and Methods: Three groups with ten samples in each group were designed for this study. They were Group 1 - Untreated PEEK, Group 2 - TiO 2 -coated PEEK, Group 3 - TiO 2 -blended PEEK. The PEEK samples were prepared according to the ISO standard 15309:2013 and milled to size of 15 mm × 2 mm, and the surfaces were finished with grit-blasted alumina of size 20 μm. In this 10 samples were chosen for Group 1. Group 2 samples were prepared by coating TiO 2 nanoparticles by arc ion plating, and Group 3 samples were prepared by blending TiO 2 nanoparticles in HAAKE rheocord with degree of blending analyzed by torque rheometer. These samples were tested for cytotoxicity using human osteosarcoma cells, and alkaline phosphatase (ALP) activity was performed to evaluate and quantify the bone mineralization process. The cross-sectional and the fracture morphology of coatings was observed by a field emission scanning electron microscope (SEM) with the magnification range ×20-×200,000., Result: Results of cytotoxicity assay and ALP assay of Group 1, Group 2, and Group 3 were statistically analyzed. SEM analysis result clearly showed the difference in the matrix before and after cell adhesion., Conclusion: The results made it evident that n-TiO 2 -coated PEEK was more versatile biomaterial of choice in implant dentistry followed by n-TiO 2 -blended PEEK and untreated PEEK., Competing Interests: There are no conflicts of interest.

Introduction: Replication of natural skin colour in maxillofacial prosthesis has been traditionally done using trial and error method, as concrete shade guides are unavailable till date. Hence a novel custom made intrinsic silicone shade guide has been attempted for Indian population., Aim: Reconstruction of maxillofacial defects is challenging, as achieving an aesthetic result is not always easy. A concoction of a novel intrinsic silicone shade guide was contemplated for the study and its reproducibility in clinical practice was analysed., Materials and Methods: Medical grade room temperature vulcanising silicone was used for the fabrication of shade tabs. The shade guide consisted of three main groups I, II and III which were divided based upon the hues yellow, red and blue respectively. Five distinct intrinsic pigments were added in definite proportions to subdivide each group of different values from lighter to darker shades. A total number of 15 circular shade tabs comprised the guide. To validate the usage of the guide, visual assessment of colour matching was done by four investigators to investigate the consent of perfect colour correspondence. Data was statistically analysed using kappa coefficients., Results: The kappa values were found to be 0.47 to 0.78 for yellow based group I, 0.13 to 0.65 for red based group II, and 0.07 to 0.36 for blue based group III. This revealed that the shade tabs of yellow and red based hues matched well and showed a statistically good colour matching., Conclusion: This intrinsic silicone shade guide can be effectively utilised for fabrication of maxillofacial prosthesis with silicone in Indian population. A transparent colour formula with definite proportioning of intrinsic pigments is provided for obtaining an aesthetic match to skin tone.

The periodontal health of abutment teeth and the durability of fixed partial denture depends on the marginal adaptation of the prosthesis. Any discrepancy in the marginal area leads to dissolution of luting agent and plaque accumulation. This study was done with the aim of evaluating the accuracy of marginal fit of four unit crown and bridge made up of Ni-Cr and Cr-Co alloys under induction and centrifugal casting. They were compared to cast fixed partial denture (FPD) and soldered FPD. For the purpose of this study a metal model was fabricated. A total of 40 samples (4-unit crown and bridge) were prepared in which 20 Cr-Co samples and 20 Ni-Cr samples were fabricated. Within these 20 samples of each group 10 samples were prepared by induction casting technique and other 10 samples with centrifugal casting technique. The cast FPD samples obtained were seated on the model and the samples were then measured with travelling microscope having precision of 0.001 cm. Sectioning of samples was done between the two pontics and measurements were made, then the soldering was made with torch soldering unit. The marginal discrepancy of soldered samples was measured and all findings were statistically analysed. The results revealed minimal marginal discrepancy with Cr-Co samples when compared to Ni-Cr samples done under induction casting technique. When compared to cast FPD samples, the soldered group showed reduced marginal discrepancy.