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PURPOSE: This study evaluates the effects of a novel nanohydroxyapatite gel and Er: YAG laser on the surface roughness, surface morphology, and elemental content after dentin hypersensitivity treatments. METHODS: Dentin discs (2 × 3 × 3 mm3) were prepared from 75 human molars. Out of 75 human molars, 50 were used to evaluate surface roughness and randomly divided into five groups: Group ID (intact dentin), Group DD (demineralized dentin), Group BF (fluoride varnish/Bifluorid 10), Group Lsr (Er: YAG laser-50 mJ, 0.50 W, 10 Hz), and Group NHA (nanohydroxyapatite-containing gel). Dentin hypersensitivity was stimulated by 35% phosphoric acid for 1 min (except Group ID). The surface roughness (Ra, µm) was measured via contact profilometry (n = 10). Out of the 75 sound human molars, 25 were used to evaluate the surface morphology and elemental content using scanning electron microscopy and energy-dispersive X-ray spectroscopy (n = 5). The data were statistically analyzed using Welsch ANOVA, Games-Howell, Kruskal-Wallis, and Dunn tests (p < 0.05). RESULTS: Group Lsr showed significantly lower surface roughness than Group NHA and Group BF (p < 0.05). The SEM analysis indicated that most of the dentinal tubules were obliterated for Group NHA. Precipitant plugs with partially occluded dentinal tubules were observed for Group BF, while partially or completely occluded tubules with a melting appearance were detected for Group Lsr. The EDS analysis revealed that Group NHA and Group Lsr presented similar calcium and phosphorus amounts to Group ID. All dentin hypersensitivity treatment methods could provide promising results in terms of tubular occlusion efficiency. However, laser treatment resulted in smoother surfaces, which could help prevent dental plaque accumulation.
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AIM: Our study aimed to examine the effects of Linagliptin, Pioglitazone, and their combination on fracture healing in a diabetes rat femur fracture model. MATERIAL AND METHODS: Type 2 diabetes mellitus (T2DM) induced rats were randomly divided into four groups: non-treated diabetes group (TD), Pioglitazone group (P), Linagliptin group (L), and Pioglitazone and Linagliptin group (PL). Daily oral dosage of pioglitazone (10 mg/kg/day), linagliptin (10 mg/kg/day), and their combination were administered. Femur fractures were stabilized intramedullary. At weeks 2 and 6, rats were sacrificed for evaluation radiologically, biomechanically, histopathologically, histomorphometrically, and immunohistochemically. RESULTS: Flexural strength of the L and PL groups were significantly higher compared to the P group. The highest healing score was in the L group and lowest in the P group, while the highest inflammation score was in the P group and lowest in the L group. A cluster of differentiation (CD) CD 34 reactivity was highest in the L group and lowest in the PL group. CONCLUSION: Linagliptin treatment significantly increased histological healing scores, callus volume, biomechanical strength, and vascularity, however, minimized the inflammatory process, which was increased by pioglitazone. The combination of linagliptin and pioglitazone restored BMD and increased biomechanical strength. Linagliptin monotherapy is rarely indicated; hence, T2DM patients with a high risk of bone fractures can be considered for combined therapy of pioglitazone and linagliptin.
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Abstract This study evaluates the effect of curing modes and times on the mechanical properties of nanocomposites. Two nanocomposite resins were investigated: suprananohybrid (Estelite Posterior Quick; EP) and nanohybrid (Solare X; SX). They were polymerized with a light-emitting diode light-curing units (LED LCU, Valo) as follows: standard mode for 20s (ST20), high power mode for 12s (HP12), high power mode for 20s (HP20), extra power mode for 6s (XP6), and extra power mode for 20s (XP20). For Vickers microhardness (HV), disc-shaped specimens were fabricated (n=10). For the three-point bending test, bar-shaped specimens were fabricated (n=10). Flexural strength and resilience modulus were calculated. The fractured surfaces and specimen surfaces of composites were observed using scanning electron microscopy. The data were analyzed with repeated measures ANOVA, two-way variance, and Bonferroni tests (p<0.05). On the top and bottom surfaces of the EP nanocomposite resin, ST20 and HP12 revealed statistically higher HV than with XP6. Moreover, HP20 and XP20 had statistically higher HV than HP12 and XP6. For the SX nanocomposite resin, HP20 had statistically higher HV than HP12. For EP and SX, there were no significant differences in flexural strength and resilience modulus regarding the curing modes and times. Furthermore, SX demonstrated lower mechanical properties than EP. Scanning electron microscopy indicated that both nanocomposites had similar surface appearances. However, with all curing modes and times, SX exhibited layered fractures and more crack formations than EP. Different curing modes and times could influence the microhardness of nanocomposites.
Resumen Este estudio evalúa el efecto del modo y tiempo de fotocurado sobre las propiedades mecánicas de los nanocompuestos. Se investigaron dos resinas nanocompuestas: supra-nanohíbrida (Estelite Posterior Quick; EP) y nanohíbrida (Solare X; SX). Se polimerizaron con unidades de fotopolimerización de diodos emisores de luz (LED LCU, Valo) de la siguiente manera: modo estándar durante 20s (ST20), modo de alta potencia durante 12s (HP12), modo de alta potencia durante 20s (HP20) , modo extra power durante 6s (XP6) y modo extra power durante 20s (XP20). Para la microdureza Vickers (HV), se fabricaron especímenes en forma de disco (n=10). Para el ensayo de flexión de tres puntos, se fabricaron probetas en forma de barra (n=10). Se calcularon la resistencia a la flexión y el módulo de resistencia. Las superficies fracturadas se observaron mediante microscopía electrónica de barrido. Los datos se analizaron con ANOVA varianza de dos vías y pruebas de Bonferroni (p<0,05). En las superficies superior e inferior de la resina nanocompuesta EP, ST20 y HP12 revelaron un HV estadísticamente mayor que con XP6. Además, HP20 y XP20 tenían un HV estadísticamente más alto que HP12 y XP6. Para la resina nanocompuesta SX, HP20 tenía un HV estadísticamente más alto que HP12. Para EP y SX, no hubo diferencias significativas en la resistencia a la flexión y el módulo de resistencia con respecto al modo y tiempo de fotocurado. Además, SX demostró propiedades mecánicas inferiores que EP. La microscopía electrónica de barrido indicó que ambos nanocompuestos son similares en la superficie. Sin embargo, SX exhibió fracturas en capas y más formaciones de grietas que EP. Diferentes modos y tiempos de fotocurado podrían influir en la microdureza de los nanocompuestos.
