Photobiomodulation of inflamed dental pulp stem cells under different nutritional conditions.

Aim: The present study aimed to investigate photobiomodulation's (PBM) effect on inflamed dental pulp stem cells (IDPSCs) under different nutritional conditions. Methods: Cell proliferation and odontogenic differentiation were evaluated using the MTT assay and real-time quantitative reverse transcription PCR, respectively after laser PBM of cells in 5 or 10% fetal bovine serum (FBS) culture conditions. Results: A significant positive effect of laser irradiation on cell proliferation under both nutritional conditions after 24 and 48 h was observed. DMP-1 gene expression increased in the groups with laser irradiation and 5% FBS. Comparison of gene expression levels in the four groups revealed no statistically significant stimulatory effect. The highest gene expression was observed in the non-laser group with 5% FBS. Conclusion: Further studies are required to obtain an irradiation setup to ideally improve inflamed dental pulp stem cells' proliferation and differentiation.

Cone-beam computed tomographic analysis of apical transportation and centering ratio of ProTaper and XP-endo Shaper NiTi rotary systems in curved canals: an in vitro study.

BACKGROUND: Cleaning and shaping of the root canal system is an important step of endodontic treatment. Canal transportation is a common procedural error in preparation of curved canals. This study aimed to compare the canal transportation and centering ratio of two rotary files in curved canals using cone-beam computed tomography (CBCT). METHODS: Forty-four extracted human mandibular first molars with mature apices and 10° to 30° apical curvature were selected. The samples were randomly divided into two groups (n = 22) with similar curvature. The canals were prepared with ProTaper and XP-endo Shaper file systems according to the manufacturers' instructions. The CBCT images were obtained using Cranex 3D CBCT scanner before and after root canal preparation, and canal transportation and centering ratio of the files at 3, 4 and 5 mm levels from the apex were calculated. Data were compared between the two groups using independent t-test at 0.05 level of significance. RESULTS: The ProTaper Universal caused greater canal transportation and had lower centering ratio than XP-endo Shaper in both mesiodistal and buccolingual directions at all levels from the apex. The difference between the two groups regarding canal transportation was significant at all levels from the apex in buccolingual direction (P < 0.05) except for 3 mm from the apex (P > 0.05). The difference between the two groups regarding centering ratio was not significant (P > 0.05) in mesiodistal direction at all levels except for 4 mm from the apex (P < 0.05). CONCLUSION: The ProTaper Universal causes greater canal transportation in both buccolingual and mesiodistal directions than XP-endo Shaper.

Evaluating reproductive performance of three estrus synchronization protocols in Ghezel ewes.

Although estrus synchronization considered valuable management tools for improving reproductive performance of ewes, their high expenses and complicated usage prevent sheep farmers to apply these techniques. Therefore, the present study was designed to compare three protocols of estrus synchronization on reproductive performance of Ghezel ewes. For this reason, 27 Ghezel ewes were assigned to three estrus synchronization treatment groups based on a completely randomized design included: progestogen sponge for 12 days + 500 IU eCG at the time of sponge withdrawal (P4eCG group, expensive synchronization), two doses of 75 µg cloprostenol with 12 days interval (CLO group, economical synchronization), and CLO +500 IU eCG at day 12 (CLOeCG group, moderately priced synchronization). Four consecutive blood samples were also collected during the experiment to evaluate progesterone concentrations. The results of the present experiment showed that pregnancy and lambing rates of the first estrus as well as blood progesterone concentration were not affected by the treatments (P > 0.05), though total pregnancy and lambing rates were higher in both P4eCG and CLOeCG groups (P < 0.01). Accordingly, both P4eCG and CLOeCG protocols successfully improved reproductive traits of ewes, though CLOeCG protocol is an advisable technique for sheep farmers through its moderate price, simple application, and high reproductive performance.