Cytotoxicity Evaluation of Various Composite Resin Materials: An In Vitro Study.

Aim This study aimed to determine and compare the cytotoxicity of light-cured composite resin (Enlight light cure composite (Ormco, Glendora, California, USA)), light-cured acrylic resin (Orthocryl LC (Dentaurum, Ispringen, Germany)), and the self-cure acrylic (DPI RR cold cure acrylic (Dental Products of India, Bombay Burmah Trading Corporation Ltd., Mumbai, India)) material and to determine which component is best to be used for the purpose of nasal stent fabrication in the nasoalveolar molding (NAM) technique for cleft therapy. Methods Circular discs made from Enlight light cure composite, Orthocryl LC, and self-cure acrylic were submerged for 24 hours in gingival fibroblast media (three discs of each material) and control medium (three discs of each material) that were both contained in plates. After analyzing the optical densities of the plates, the cytotoxicity of the products was assessed by measuring cell viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The compiled data was analyzed using IBM SPSS Statistics for Windows, V. 23.0 (IBM Corp., Armonk, NY). The normality of the data was evaluated using the Shapiro-Wilk test. One-way analysis of variance (ANOVA) and pairwise comparison made with Tukey's honestly significant difference (HSD) post hoc test with a significance level (p) of 0.05 were considered. Results The percentage of cell viability was between 80% and 150%. A significant mean difference was noted in the cell viability between the three groups (p=0.009). High mean cell viability was seen in Orthocryl LC. However, there was no significant mean difference between Orthocryl LC and Enlight light cure composite material (p=0.854). Conclusion Both Orthocryl LC and Enlight light cure composite materials are less cytotoxic when compared to the self-cure acrylic resin material and can be used to fabricate the nasal stent component for infants with cleft defects, undergoing NAM procedure.

Evaluation of the accuracy of full-arch impressions between three different intraoral scanners and conventional impressions: A prospective in vivo study.

Background: This in-vivo study evaluated the accuracy of full-arch digital impressions obtained through different intraoral scanning technologies regarding trueness and efficiency against the standard alginate impressions. Methods: Alginate impressions were taken from 50 subjects, and the resulting stone casts were scanned using the Trios 3Shape desktop scanner. In-vivo scans were conducted on each participant using three intraoral scanners: Medit, CEREC Primescan, and 3Shape Trios. The scanned files were superimposed onto two software platforms: the 3Shape Orthoanalyser and Geomagic software. This superimposition was performed against the reference model to calculate 3D and 2D deviations, enabling efficiency comparisons between digital and traditional workflows based on work time in minutes. Measurements and comparisons were made in three planes: transverse, sagittal, and vertical dimensions for all the models and stone casts. Statistical analysis employed SPSS 23, with the significance level set at P<0.05. Results: Significant deviations were observed between the three intraoral scanners and the alginate impression, with molar and premolar areas showing greater imprecision across dental arches. Compared to the alginate technique, Medit i500 tended to reduce the transverse dimension in the areas mentioned above, while CEREC exhibited higher precision. Molar and premolar areas emerged as the regions with the greatest discrepancies, both in excess and deficiency, compared to the alginate impression. This difference in dimensions was, however, statistically insignificant overall. 3Shape Trios exhibited the shortest scan times, indicating higher efficiency. Among the intraoral scanners, Medit recorded the longest scanning duration. Conclusion: Accepting the null hypothesis, the scans obtained using all three scanners were comparable with statistically insignificant differences in the measurements. The three scanners differed in the total scan time taken, with the Medit scanner requiring the longest scan time and the 3Shape TRIOS 3 scanner demonstrating the shortest scan duration.

Characterization, Shear Bond Strength Assessment, and Antibacterial Effects of an Orthodontic Composite Containing Stannous Oxide (SnO2) Nanoparticles.

Background This study aimed to determine the antibacterial properties of orthodontic adhesive infused with stannous oxide nanoparticles (NPs) against Lactobacillus acidophilus and Streptococcus mutans bacteria, along with assessing the shear bond strength (SBS) of this composite when compared to conventional, non-infused composites. Methods A concentration of 1% w/w tin dioxide NPs (SnO2 NPs) was added to Transbond XT Orthodontic Adhesive. This modified composite material was used to prepare composite discs for the evaluation of its antibacterial properties against L. acidophilus bacteria and S. mutans bacteria using the biofilm inhibition test. To evaluate the SBS of this modified adhesive material, 50 extracted premolar teeth were collected and divided into two groups, with 25 teeth in each group (n = 25). Orthodontic stainless steel brackets were bonded to these extracted teeth using the modified composite. A comparative analysis of the SBS of the nano-infused composite group was then performed against that of the control group using an Instron universal testing machine. Results Growth inhibition zones were produced around the composite discs infused with SnO2 NPs for both bacterial strains. After performing the biofilm inhibition test, it can be inferred that the nano-infused composite is capable of inhibiting the bacterial count better than the control group. A statistically significant difference was observed between the two groups, with the SBS of the nano-infused composite being higher (16.89 MPa) than the non-infused composite adhesive (15.49 MPa). Conclusion The antibacterial activity of orthodontic composites modified with SnO2 NPs was significant compared with conventional composites. The control group showed less SBS when compared to the NP-infused composite, with a statistically significant difference in mean SBS values between both groups.

US Initiative to Eliminate Racial and Ethnic Disparities in Health: The Impact on the Outcomes of ST-Segment-Elevation Myocardial Infarction in New Jersey.

Background In 1998, President Clinton launched a federal initiative to eliminate racial and ethnic health disparities. The impact on the outcomes of ST-segment-elevation myocardial infarction has not been well studied. Methods and Results ST-segment-elevation myocardial infarction outcomes from 1994 to 2015 were studied in 7942 Black, 27 665 Hispanic, and 88 727 White patients with first admission of ST-segment-elevation myocardial infarction using the Myocardial Infarction Data Acquisition System. Logistic regressions were used to assess mortality adjusting for demographics, comorbidities, and interventional procedures. There was an overall rise from 1994 to 2015 in the use of percutaneous coronary interventions in all 3 groups. Before 1998, White patients received more percutaneous coronary interventions compared with Black and Hispanic patients (P<0.05). After 1998, the disparity in use of percutaneous coronary interventions in Black and Hispanic patients was greatly reduced compared with White patients, and the difference reversed in favor of Hispanic patients after 2005 (P<0.05). There was an overall downward trend of in-hospital mortality without evidence of disparity among Black, Hispanic, and White patients. A linear regression model was used with a change point in 1998. Before 1998, the slope of 1-year all-cause and cardiovascular mortality was not statistically significant. After 1998, the mortality showed negative slopes for all 3 groups, however, with lower overall crude mortality for Hispanic patients compared with Black and White patients (P<0.0001). Conclusions The initiative launched in 1998 may have contributed to a reduction in percutaneous coronary intervention usage disparity in patients with ST-segment-elevation myocardial infarction. Short- and long-term mortality decreased in all 3 groups, but more in the Hispanic population.

Second stem cell transplantation for treatment of relapsed/refractory multiple myeloma after first autologous stem cell transplant: A 15-year retrospective institutional analysis.

Background: Multiple myeloma remains an incurable disease, with the majority of patients relapsing after autologous stem cell transplant (ASCT). After relapse, second transplant remains one of the therapeutic options, along with novel agents. Methods: We reviewed the data of our patients who underwent ASCT for myeloma (N = 202) over the last two decades (2004-2019). Of these, 12 patients underwent a second transplant. Results: Out of 12 patients, nine underwent second autologous stem cell transplant, whereas three received an allogeneic stem cell transplantation (Allo-SCT). Median progression-free survival (PFS) after the first ASCT was 32 months (5-84 months). Median interval between both the transplants was 35 months (4-159 months). Median age of our cohort which underwent second transplant was 56 years. Overall response rate (ORR) post-second transplant on day +100 was 83.3%, without any transplant-related mortality (TRM). With the use of preemptive plerixafor, none of our patients required a second day for stem cell harvest. Median CD34 dose of stem cells infused was 4.11 × 106/kg. Similar to the first ASCT, the median time to neutrophil and platelet engraftment was 11 and 12 days, respectively. At a median follow-up of 41 months, estimated 3-year PFS and overall survival (OS) was 37% ± 15% and 63% ± 15%, respectively. Conclusion: ">Among all relapsed myeloma patients who were transplant eligible, 11% underwent a second transplant. Second transplant is well tolerated with similar time to engraftment after first ASCT. Hence, we believe that second transplant is a feasible, cost-effective option in a resource-limited setting, which should be more widely utilized.