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The aim of this study was to investigate whether simultaneous irradiation at 660 and 808 nm generates different patterns of oxidative/antioxidative activities compared to consecutive irradiation. Primary cultures of gingival keratinocytes and fibroblasts were exposed to a diose laser (660 ± 2 nm and 808 ± 2 nm, 100 mW, 0.09 cm2 spot area) using double irradiation with the two wavelengths (consecutive or simultaneous) for 6, 10, and 20 s. The two irradiation regimens did not increase cell viability in any of the experimental conditions. Lipid peroxidation was increased after consecutive irradiation in epithelial cells, which was not detected after simultaneous irradiation. After 20s of the simultaneous mode, ROS levels increased, but antioxidative balance decreased. In the fibroblasts, the two double irradiations induced ROS reduction, increase in lipid peroxidation, and improvement of antioxidative balance, mainly after the 20 s irradiation time. In conclusion, simultaneous and consecutive irradiation induced distinct oxidative stress modulation in oral epithelial cells and fibroblasts. The imbalance in the oxidative system observed after longer exposures, allied with the absence of a significant increase in the viability of the two cell types, suggests a contraindication for longer simultaneous irradiation in clinical situations that demand cellular stimulation. [ABSTRACT FROM AUTHOR]

5‐Fluoroufacil (5FU) is a chemotherapeutic agent indicated for solid tumors but causes oral mucositis, which can be prevented and treated using photobiomodulation therapy (PBMT). It is unknown whether PBMT modifies DNA damage induced by 5FU in oral cells. The aim of this study was to investigate the effect of PBMT on DNA damage and repair and on oxidative stress in gingival fibroblasts exposed to 5FU. Primary gingival fibroblasts were exposed to 5FU and then treated with a laser (660 nm, 100 mW, 1 W cm−2, 0.09 cm2 spot area) for three different irradiation times (6, 10 or 20 s). Six‐second irradiation decreased DNA damage and lipidic peroxidation. All irradiated groups showed low H2AX levels and increased p53 expression. Ten‐second irradiation showed a trend to induce high lipidic peroxidation levels and DNA damage than other irradiation groups. In conclusion, the PBMT effect on DNA damage and repair was dependent on the time irradiation: 6 s‐time irradiation (6.6 J cm−2) protect gingival fibroblasts from 5FU‐related genotoxicity and oxidative stress, whereas 10s‐ and 20s‐time irradiations (11.1 J cm−2 and 22.2 J cm−2, respectively) increased the risk of DNA damage after the 5FU exposure. [ABSTRACT FROM AUTHOR]

Background: Recombinant human bone morphogenetic protein 2 (rhBMP-2) is an osteoinductor frequently used for bone regeneration in oral and maxillofacial surgery. There is no consensus about the ideal carrier for this growth factor. The aim of this study was to compare the bone augmentation, bone microarchitecture, and biodegradation rate of additional carriers to rhBMP-2/absorbable collagen sponge (ACS) in a vertical guided bone regeneration model.Methods: Four titanium cylinders were fixed onto the calvaria of rabbits (n = 20) that received (n = 10) or not (n = 10) rhBMP-2/ACS in conjunction with one of the carriers: beta-tricalcium phosphate (β-TCP), biphasic calcium phosphate (BCP), bovine bone mineral (BBM) or blood clot. The samples were analyzed by means of microcomputed tomography and histomorphology after 14 weeks.Results: All the materials with rhBMP-2/ACS exhibited improvement on bone augmentation, mainly BCP (P = 0.033) and β-TCP (P = 0.038), in the upper portion of the cylinder. Although trabecular anisotropy was improved in all the materials groups, trabecular connectivity was diminished when the biomaterials received rhBMP-2/ACS. Resorption rate of the remaining biomaterial was improved by rhBMP-2/ACS, mainly in BBM (P <0.01) and β-TCP (P <0.01). BBM exhibited the highest osteoclast density compared with the other materials groups.Conclusions: BCP and β-TCP biomaterials exhibited a synergic effect with rhBMP-2/ACS, acting as suitable and viable carriers for vertical bone augmentation. The addition of rhBMP-2 significantly affected the biodegradation of β-TCP and BBM, accelerating the resorption of these materials. [ABSTRACT FROM AUTHOR]

Aim: Selective outcome reporting (SOR) is a type of bias that occurs when the primary outcome of a trial protocol is changed or omitted in the paper. The purpose of this study was to evaluate the prevalence of SOR in publications of randomized clinical trials (RCT) concerning dental implants. Materials and Methods: Two reviewers independently screened protocols registered at ClinicalTrials.gov until February/2019. If the protocol met the eligibility criteria, the reviewers tried to identify the corresponding publication. Data extraction was carried out by the same reviewers. Primary and secondary outcomes were recorded for each trial and compared to outcomes previously described in protocols. Results: A total of 49 protocols were included. SOR was identified in 27 (55.1%) trials. The major discrepancies were as follows: protocol‐defined primary outcome omitted in the publication (n = 6, 12.2%), new primary outcome introduced (n = 8, 16.3%), discrepancy in the primary outcome time frame (n = 17, 34.7%) and new secondary outcome introduced (n = 31, 63.3%). SOR was significantly associated with industry funding (p = 0.04) and timing of registration (p = 0.04). Conclusions: Our results indicate a high rate of SOR in dental implants clinical trials. Use of registry data during the peer‐review process may help decreasing SOR. [ABSTRACT FROM AUTHOR]