Effects of Erbium Family Laser on Shear Bond Strength of Composite to Dentin After Internal Bleaching

Introduction: The aim of this study was to assess the effect of surface treatment with erbium: yttrium-aluminum-garnet (Er:YAG) and erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers on shear bond strength of composite resin to recently bleached dentin.Methods: In this study, 40 extracted human premolars were selected. The teeth were cut 4 mm apical to the cusp tip and were randomly divided into four groups (n = 10 in each group) for shear bond strength testing. For bleaching, 35% hydrogen peroxide (H2o2) gel (Opalescence Endo, Ultradent, South Jordan, UT, USA) was applied to dentin surfaces of all specimens for 10 days. Before etching and bonding, in Er,Cr:YSGG and Er:YAG laser groups, dentin surfaces were irradiated with Er,Cr:YSGG and Er:YAG lasers, respectively. In Er,Cr:YSGG group, Er:YAG group and control group, composite restoration was performed immediately after bleaching while in common procedure group, composite restoration was performed after seven days. The teeth were then subjected to shear bond strength testing machine. The data were statistically analyzed using analysis of variance (ANOVA) and Tukey test.Results: The mean and standard deviation (SD) of shear bond strength was 4.3 ± 1.4 MPa for control group, 6.7 ± 2.0 Mpa for Er,Cr:YSGG group, 14.4 ± 3.7 Mpa for Er:YAG group and 19.4 ± 2.6 Mpa for common procedure group.Conclusion: The shear strength of composite to Er:YAG laser-treated bleached dentin was significantly higher than control group while significantly lower than common procedure

Perinatal outcome in fresh versus frozen embryo transfer in ART cycles

Background: Despite of higher pregnancy rate after frozen embryo transfer (FET) which is accepted by the majority of researches, the safety of this method and its effect on neonatal outcome is still under debate. Objective: The aim of this study was to evaluate pregnancy and neonatal outcome of FET compare to fresh cycles. Materials and Methods: In this study,1134 patients using fresh ET and 285 women underwent FET were investigated regarding live birth as primary outcome and gestational age, birth weight, gender, multiple status, ectopic pregnancy, still birth and pregnancy loss as secondary outcomes. Results: Our results showed that there is no difference between FET and fresh cycles regarding live birth (65.6% vs. 70.4% respectively). Ectopic pregnancy, still birth and abortion were similar in both groups. The mean gestational age was significantly lower among singletons in FET group compared to fresh cycles (p=0.047). Prematurity was significantly elevated among singleton infants in FET group (19.6%) in comparison to neonates born after fresh ET (12.8%) (p=0.037). Conclusion: It seems that there is no major difference regarding perinatal outcome between fresh and frozen embryo transfer. Although, live birth is slightly increased in fresh cycles and prematurity was significantly increased among singleton infants in FET grou

Fresh versus frozen embryo transfer after gonadotropin-releasing hormone agonist trigger in gonadotropin-releasing hormone antagonist cycles among high responder women: A randomized, multi-center study

Background: The use of embryo cryopreservation excludes the possible detrimental effects of ovarian stimulation on the endometrium, and higher reproductive outcomes following this policy have been reported. Moreover, gonadotropin-releasing hormone agonist trigger in gonadotropin-releasing hormone (GnRH) antagonist cycles as a substitute for standard human chorionic gonadotropin trigger, minimizes the risk of ovarian hyperstimulation syndrome (OHSS) in fresh as well as frozen embryo transfer cycles (FET). Objective: To compare the reproductive outcomes and risk of OHSS in fresh vs frozen embryo transfer in high responder patients, undergoing in vitro fertilization triggered with a bolus of GnRH agonist. Materials and Methods: In this randomized, multi-centre study, 121 women undergoing FET and 119 women undergoing fresh ET were investigated as regards clinical pregnancy as the primary outcome and the chemical pregnancy, live birth, OHSS development, and perinatal data as secondary outcomes. Results: There were no significant differences between FET and fresh groups regarding chemical (46.4% vs. 40.2%, p=0.352), clinical (35.8% vs. 38.3%, p=0.699), and ongoing (30.3% vs. 32.7%, p=0.700) pregnancy rates, also live birth (30.3% vs. 29.9%, p=0.953), perinatal outcomes, and OHSS development (35.6% vs. 42.9%, p=0.337). No woman developed severe OHSS and no one required admission to hospital. Conclusion: Our findings suggest that GnRHa trigger followed by fresh transfer with modified luteal phase support in terms of a small human chorionic gonadotropin bolus is a good strategy to secure good live birth rates and a low risk of clinically relevant OHSS development in in vitro fertilization patients at risk of OHSS