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Endodontic microsurgery is a vital treatment modality for teeth with persistent periradicular pathoses that have not responded to nonsurgical retreatment. The principle is to determine the reason for failure, completely eliminate the infection and promote periapical healing. Within recent years, endodontic microsurgery has evolved to become standardized and presents with a high success rate. However, its outcome is still influenced by many factors, including anatomy, periodontal condition, crown-to-root ratio, occlusion, the type of periradicular lesion, and prosthesis. Moreover, endodontists always concentrate on “the apex”, paying little attention to the general preoperative evaluation, accurate diagnosis, and comprehensive treatment plan. This article reviews the latest literature on these issues and the clinical experience of our research group and discusses the correlation between endodontic microsurgery and other oral disciplines, including periodontology, prosthodontics, oral implantology, oral and maxillofacial surgery and orthodontics. The oral interdisciplinary assessment should be made with comprehensive consideration of the root canal system, periradicular lesion, adjacent anatomical relationships, periodontal condition, occlusion, and esthetic rehabilitation. Based on these findings, the continuity of treatment will be optimized, and the best treatment plan will be proposed to provide clinical strategies for the diagnosis and treatment of complex periradicular diseases.

Human dental pulp stem cells (hDPSCs) play a vital role in the regeneration of the pulp-dentin complex after pulp disease. While the regeneration efficiency relies on the odontoblastic differentiation capacity of hDPSCs, this is difficult to regulate within the pulp cavity. Although nicotinamide riboside (NR) has been found to promote tissue regeneration, its specific role in pulp-dentin complex regeneration is not fully understood. Here, we aimed to explore the role of NR in the odontoblastic differentiation of hDPSCs and its underlying molecular mechanism. It was found that NR enhanced the viability and retarded senescence in hDPSCs with higher NAD+/NADH levels. In contrast to the sustained action of NR, the multi-directional differentiation of hDPSCs was enhanced after NR pre-treatment. Moreover, in an ectopic pulp regeneration assay in nude mice, transplantation of hDPSCs pretreated with NR promoted the formation of a dentin-like structure surrounded by cells positively expressing DMP-1 and DSPP. RNA-Seq demonstrated inhibition of the HIF-1 signaling pathway in hDPSCs pretreated with NR. The number of HIF-1α-positive cells was significantly decreased in hDPSCs pretreated by NR in vivo. Similarly, NR significantly downregulated the expression of HIF-1α in vitro. The findings suggested that NR could potentially regulate hDPSC odontoblastic differentiation and promote the development of innovative strategies for dental pulp repair. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, urethane methacrylate quaternary ammonium compound (UDMQA-12) was used to partially replace 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropyl)-phenyl]propane (Bis-GMA) as the base compound of dental resin system. Double bond conversion, polymerization shrinkage, flexural strength (FS) and flexural modulus (FM), water sorption (WS) and water solubility (WSL), and antibacterial activity of all experimental resins were investigated. Bis-GMA/triethyleneglycol dimethacrylate resin without UDMQA-12 was used as a control group. Results showed that UDMQA-12 had no negative influence on the double bond conversion of the resin, but polymerization shrinkage, FS, and FM decreased with the increasing of UDMQA-12 concentration, whereas WS and WSL increased with it. UDMQA-12-containing polymer showed antibacterial activity when concentration of UDMQA-12 was 30% or more. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21395; View this article online at . DOI 10.1002/adv.21395 [ABSTRACT FROM AUTHOR]

The time series (TS) of the normalized difference vegetation index (NDVI) has been widely used to trace the temporal and spatial variability of terrestrial vegetation. However, many factors such as atmospheric noise and radiometric correction residuals conceal the actual variation in the land surface, and thus hamper the TS information extraction. To minimize the negative effects of these noise factors, we propose a new method to produce a synthetic gap-free NDVI TS from the original contaminated observation. First, the key temporal points are identified from the NDVI time profiles based on a generally used rule-based strategy, making the TS segmented into several adjacent segments. Then, the observed data points in each segment are fitted with a weighted double-logistic function. The proposed dynamic weight reassignment process effectively emphasizes cloud-free points and deemphasizes cloud-contaminated points. Finally, the proposed method is evaluated on more than 3,000 test points from three selected Sentinel-2 tiles, and is compared with the generally used Savitzky-Golay (S-G) and harmonic analysis of time series (HANTS) methods from qualitative and quantitative aspects. The results indicate that the proposed method has a higher capability of retaining cloud-free data points and identifying outliers than the others, and can generate a gap-free NDVI time profile derived from a medium-resolution satellite sensor. [ABSTRACT FROM AUTHOR]