RESUMEN
Objective: Zirconia cores have limited light transmittance and data are scarce on light transmission through zirconia cores with and without the veneering ceramic
Methods: In this in vitro study, Disc-shaped specimens [11.5 mm in diameter and 0.4 [0.05] mm in thickness] were fabricated of three types of zirconia namely Mamut, Heany and ZirkonZahn [n=5]. A disc-shaped specimen [11.5 mm in diameter and 0.65 [0.05] mm in thickness] of veneering ceramic [Cerabien ZR, Kuraray, Noritake, Japan] was also fabricated. The intensity of light transmitted through the zirconia specimens with and without the veneering ceramic was recorded using a light curing unit [LED, SDI Radii Plus, Australia] and its respective radiometer [LED Radiometer, SDI, Australia]. Data were analyzed using repeated measures ANOVA and Tukey's HSD test
Results: A significant difference was noted in light transmission among different types of zirconia before and after veneering. After veneering, light transmission decreased in all specimens and the reduction in light transmission in Zirkonzahn group was significantly greater than that in Heany and Mamut groups [p<0.001]
Conclusion: Veneered zirconia systems have limited translucency and ceramic veneering significantly decreases light transmission through zirconia
RESUMEN
Objective: In dental treatments, use of carriers for targeted antibiotic delivery would be optimal to efficiently decrease microbial count. In this study, gentamicin was loaded into polylactic co-glycolic acid [PLGA] microspheres and its release pattern was evaluated for 20 days
Methods: In this experimental study, PLGA microspheres loaded with gentamycin were produced by the W/O/W method. The correct morphology of loaded microspheres was ensured using scanning electron microscopy [SEM]. The rate of drug release from polymeric microspheres into the phosphate buffered saline [PBS] solution was measured during a 20-day period using spectroscopy. Data were analyzed using one-way ANOVA
Results: SEM micrographs showed that the produced microspheres had smooth and nonporous surfaces and 30-micron diameter. Assessment of the pattern of drug release from the PLGA microspheres loaded with gentamycin revealed a burst release on day six followed by a stable pattern of release until day 20
Conclusion: Considering the biocompatibility of PLGA and optimal pattern of drug release, PLGA microspheres loaded with gentamicin can be successfully used for infection control and reduction of microbial count in dental treatments