The effect of erosive beverages and polishing systems on the surface properties of nanohybrid composite resin.

Aims and Background: The aim of this study is to evaluate the surface microhardness and roughness of composites treated with three different polishing systems exposed to two different corrosive beverages. Material and Methods: Ninety-six composite resin disks were randomly divided into four groups, one of which was the control group. The surface roughness and microhardness values were measured after 24 h in the polishing process. The samples were divided into three subgroups and kept in distilled water, cola, and ice tea for 20 min a day for 14 days. Then, the roughness and microhardness measurements of the samples were taken again. Two samples randomly selected from each group were examined using a scanning electron microscope (SEM) and analyzed statistically using the two way anova (ANOVA) and Duncan tests. Results: A statistically significant difference was found between the roughness and hardness values at the end of 24 h and 14 days. Onegloss (OG), Dentoflex (DF), and Super-snap (SNP) polish systems showed the highest roughness in the cola group, respectively. Microhardness values: The unpolished group had the lowest significant microhardness in the coke group (P < 0.05). Conclusion: In this study, it was seen that the lowest success rate was the OG polishing system.

Preserving the ligamentum flavum in lumbar discectomy: a new technique that prevents scar tissue formation in the first 6 months postsurgery.

OBJECTIVE: Postoperative fibrosis is one of the most important causes of failed back surgery syndrome after lumbar disc surgery. Numerous natural and synthetic materials have been investigated as means to prevent or reduce postoperative scarring after these operations. Preservation of the ligamentum flavum for this purpose has not been studied in depth. A prospective, randomized, controlled clinical study was conducted. The aim was to present a new technique for preserving the ligamentum flavum during lumbar discectomy, and to evaluate whether this helps prevent or diminish postoperative fibrosis. METHODS: Twenty patients with unilateral L5-S1 disc herniation were randomly divided into two equal groups. Group A patients underwent classic microlumbar discectomy, and Group B patients underwent the same procedure but with preservation of the ligamentum flavum. Visual analog pain scale (VAPS) scores, Oswestry scale scores, and straight-leg raising angles were recorded preoperatively and at 6 months postoperatively. Differences between the pre-operative and postoperative findings for each group were statistically compared using the Wilcoxon test. Magnetic resonance imaging was also done at 6 months to assess the extent of postoperative fibrosis, and a "scarring grade" was recorded for each patient. The group findings for this were analyzed with Levene's test. RESULTS: Both groups' clinical parameters were significantly improved at 6 months postsurgery. In Group A, the mean pre- and postoperative VAPS scores were 9.2 and 3.2, respectively (P < 0.05); the corresponding mean Oswestry scale scores were 88 and 28.2, respectively (P < 0.05); and the corresponding mean straight-leg raising angles were 290 and 630, respectively (P < 0.05). In Group B, the mean pre- and postoperative VAPS scores were 9.2 and 2.6, respectively (P < 0.05); the corresponding mean Oswestry scores were 85.2 and 22.2, respectively (P < 0.05); and the corresponding mean straight-leg raising scores were 260 and 710, respectively (P < 0.05). The mean scarring grades in Groups A and B were 1.8 and 1.0, respectively (P < 0.05). CONCLUSION: The groups both showed satisfactory clinical outcomes and the improvements were comparable; however, the group with preserved ligamentum flavum showed significantly less local fibrosis at 6 months postoperatively. The authors speculate that this surgical technique provides a physical protective barrier that can reduce or even eliminate fibrosis-related complications after lumbar disc surgery.

Landmarks in diabetes care: a historical perspective.

Since the discovery and isolation of insulin in 1921, many advances in diabetes research and management have been made. Funda Suleyman charts the successes over the years.