基于CBCT数据的影像学方法在口腔正畸的临床应用

目的:研究与分析关于基于CBCT数据的影像学方法在口腔正畸的临床应用效果。方法:选择我院口腔正畸科为本次实验的研究地点,选取在2018年11月—2019年4月期间在我院就诊的口腔患者中需要口腔正畸的患者共80例,将其平均分为两个组,第一个组为平片组(对照组),采用传统的口腔平片摄影,得到平片摄影数据,第二组为CBCT组(实验组),采用锥形束计算机断层扫描(CBCT),得到CBCT影像数据。两组分别根据检查得到的数据进行口腔正畸治疗方案进行指导建议,将治疗后两组结果进行对比分析,整理实验结果,得出基于CBCT数据的影像学方法在口腔正畸治疗中的临床运用效果。结果:CBCT组中30例得分10分、8例得分在6~8分、2例得分在0~5分,总满意度达到95%;平片组中10例得分10分、15例得分在6~8分、15例得分0~5分,总满意度为62.5%。实验数据具有统计学意义(P<0.05)。结论:通过实验结果显示,基于CBCT数据的影像学方法在口腔正畸的临床应用效果比平片的应用效果更好,在检测口腔正畸的病因中准确率更高,对正畸治疗能够更好的提供相关的治疗指导,可以在口腔临床上广泛运用。

Numerical Simulation on Ice Shedding Phenomena in Turbomachinery

In the jet engine, icing phenomena occur primarily on the fan blades, the FEGVs （fan exit guide vanes）, the splitter, and the low-pressure compressor. Accreted ice disturbs the inlet flow and causes large energy losses. In addition, ice accreted on a fan rotor can be shed from the blade surface due to centrifugal force and can damage compressor components. This phenomenon, which is typical in turbomachinery, is referred to as ice shedding. Although existing icing models can simulate ice growth, these models do not have the capability to reproduce ice shedding. In the present study, we develop an icing model that takes into account both ice growth and ice shedding. Furthermore, we have validated the proposed ice shedding model through the comparison of numerical results and experimental data, which include the flow rate loss due to ice growth and the flow rate recovery due to ice shedding. The simulation results for the time at which ice shedding occurred and what were obtained using the proposed ice shedding model were in good agreement with the experimental results.