Expression of heat shock protein 27 in cigarette smoke extract-induced injury of human gingival fibroblasts / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This research aimed to observe the expression of heat shock protein 27 (HSP27) in human gingival fibroblasts (HGFs) cell injury induced by different concentrations of cigarette smoke extract (CSE).</p><p><b>METHODS</b>The third to eighth generations of cultured HGFs were treated with serially diluted CSE of different concentrations (0, 2.5%, 5.0%, 12.5%, 25.0%, 50.0%). Wound-healing assay was performed to determine the migration of HGFs, and Western blot was used to determine the expression of HSP27.</p><p><b>RESULTS</b>The migration capability of HGFs weakened with the increase of CSE concentration. HSP27 expression was negative in normal HGFs but positive in CSE-intervened HGFs in a concentration-dependent manner.</p><p><b>CONCLUSION</b>HSP27 concentration increased in the CSE-induced injury of HGFs. This finding suggests that HSP27 plays an important role in CSE-induced epithelial injury.</p>

Dental plaque microcosm biofilm behavior on a resin composite incorporated with nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To develop a resin composite incorporated with nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt, and to measure its effect on human dental plaque microcosm biofilm.</p><p><b>METHODS</b>A novel nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt was synthesized according to methods introduced in previous research. Samples of the novel nano-antibacterial inorganic fillers were modified by a coupling agent and then added into resin composite at 0%, 5%, 10%, 15% or 20% mass fractions; 0% composite was used as control. A flexural test was used to measure resin composite mechanical properties. Results showed that a dental plaque microcosm biofilm model with human saliva as inoculum was formed. Colony-forming unit (CFU) counts, lactic acid production, and live/dead assay of biofilm on the resin composite were calculated to test the effect of the resin composite on human dental plaque microcosm biofilm.</p><p><b>RESULTS</b>The incorporation of nano-antibacterial inorganic fillers with as much as 15% concentration into the resin composite showed no adverse effect on the mechanical properties of the resin composite (P > 0.05). Resin composite containing 5% or more nano-antibacterial inorganic fillers significantly inhibited the metabolic activity of dental plaque microcosm biofilm, suggesting its strong antibacterial potency (P < 0.05).</p><p><b>CONCLUSION</b>This novel resin composite exhibited a strong antibacterial property upon the addition of up to 5% nano-antibacterial inorganic fillers, thereby leading to effective caries inhibition in dental application.</p>