Dental fear is a common problem in pediatric dentistry. Therefore, sedation for pediatric patients is an essential tool for anxiety management. Nitrous oxide/oxygen inhalation sedation is a safe, convenient, effective way to calm children. The review is about the technology of nitrous oxide/oxygen inhalation sedation and its clinical application in pediatric dentistry.
Anesthesia, Dental ; Anesthetics, Inhalation ; Child ; Conscious Sedation ; Dental Anxiety ; Humans ; Nitrous Oxide ; Oxygen ; Pediatric Dentistry

OBJECTIVETo compare shear bond strength (SBS) between composite resin core (CRC) disposed with three different surface treatments and glass ionomer cement (GIC), so that to provide theoretical basis for luting of crowns to CRC.

METHODSAccording to three different surface treatments, thirty blocks of CRC were randomly and equally divided into three groups: Roughening with diamond grit bur(RDB), RDB plus etching with Gluma Etch 35 Gel (RDBE), RDB plus coating with Adper Single Bond2 adhensive (RDBA). All CRC were cemented with GIC. All specimens were preserved in 37 degrees C water for 24 h, then SBS tests for eight specimens in each group were performed using a universal testing machine at a constant crosshead speed of 0.5 mm x min(-1). The surface topography of one CRC of each group was observed using field emission scanning electron microscope (FE-SEM) at 100 amplification. The interface between CRC and GIC was observed using FE-SEM at 500 amplification. Then the nature of failure was also recorded using FE-SEM at 25 amplification and the data were analyzed with a Kruskal-Wallis H test.

RESULTSThe surface topography of each group and the interface between CRC and GIC observed using FE-SEM were significantly different, but significant differences on the nature of failure between groups were not found (P > 0.10). SBS of each group was (4.28 +/- 0.18) MPa for RDB, (4.65 +/- 0.17) MPa for RDBE, (2.39 +/- 0.21) MPa for RDBA, respectively (P < 0.01).

CONCLUSIONThe SBS between CRC and GIC is affected by the surface treatments of CRC.

Composite Resins ; Crowns ; Dental Bonding ; Glass Ionomer Cements ; Materials Testing ; Resin Cements ; Surface Properties

Dental fear is a common problem in pediatric dentistry. Therefore, sedation for pediatric patients is an essential tool for anxiety management. Nitrous oxide/oxygen inhalation sedation is a safe, convenient, effective way to calm children. The review is about the technology of nitrous oxide/oxygen inhalation sedation and its clinical application in pediatric den-tistry.

The global features of H3K4 and H3K27 trimethylations (H3K4me3 and H3K27me3) have been well studied in recent years,but most of these studies were performed in mammalian cell lines.In this work,wegenerated the genome-wide maps of H3K4me3 and H3K27me3 of mouse cerebrum and testis using ChlP-seq and their high-coverage transcriptomes using ribominus RNA-seq with SOLiD technology.We examined the global patterns of H3K4me3 and H3K27me3 in both tissues and found that modifications are closely-associated with tissue-specific expression,function and development.Moreover,we revealed that H3K4me3 and H3K27me3 rarely occur in silent genes,which contradicts the findings in previous studies.Finally,we observed that bivalent domains,with both H3K4me3 and H3K27me3,existed ubiquitously in both tissues and demonstrated an invariable preference for the regulation of developmentally-related genes.However,the bivalent domains tend towards a "winner-takes-all" approach to regulate the expression of associated genes.We also verified the above results in mouse ES cells.As expected,the results in ES cells are consistent with those in cerebrum and testis.In conclusion,we present two very important findings.One is that H3K4me3 and H3K27me3 rarely occur in silent genes.The other is that bivalent domains may adopt a "winner-takes-all" principle to regulate gene expression.