Lopes Priscila A, Santaella Gustavo M, Lima Carlos Augusto S, Vasconcelos Karla de Faria, Groppo Francisco C
Department of Oral Diagnosis, Area of Oral Radiology, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil.
Department of Physiological Sciences, University of Campinas, Piracicaba, São Paulo, Brazil.
Dentomaxillofac Radiol. 2019 Jan;48(1):20180072. doi: 10.1259/dmfr.20180072. Epub 2018 Jul 20.
To evaluate different materials in simulating soft tissues and to analyze the influence of these materials on the mean (MPIV) and standard deviation of pixel intensity values comparing them to a gold-standard in CBCT images.
Images of three piglet heads with their soft tissues intact (gold-standard) and different simulant materials were acquired: ice, modelling wax, and ballistic gelatin, with the same thickness of the original soft tissues. The pixel intensities were measured in dental, bone and soft tissues regions, in the mandible and maxilla, for all the groups. Analysis of variance, Dunnet's, Pearson's and linear regression tests were performed.
The simulators did not significantly change the MPIV of teeth in comparison with the gold-standard ( = 0.1017). Only ice ( = 0.0156) affected the MPIV of bone. Wax ( = 0.001) and ice ( = 0.0076), but not ballistic gelatin ( = 0.5814), altered the MPIV of soft tissue regions. When assessing the influence of the location (mandible or maxilla) among the simulants, the differences were significant only for the soft tissue regions. Standard deviation was not influenced by simulants ( > 0.05), but ballistic gelatin presented the lower variability.
The ballistic gelatin was the best soft tissue simulant since it had the lowest influence on the pixel intensity values for all regions.
评估不同材料在模拟软组织方面的效果，并分析这些材料对CBCT图像中像素强度值的均值（MPIV）和标准差的影响，同时将其与金标准进行比较。
采集了三头仔猪头部软组织完整的图像（金标准）以及不同的模拟材料：冰、模型蜡和弹道凝胶，模拟材料的厚度与原始软组织相同。对所有组在下颌骨和上颌骨的牙齿、骨骼和软组织区域测量像素强度。进行方差分析、邓尼特检验、皮尔逊检验和线性回归检验。
与金标准相比，模拟器对牙齿的MPIV没有显著影响（P = 0.1017）。只有冰（P = 0.0156）影响骨骼的MPIV。蜡（P = 0.001）和冰（P = 0.0076）改变了软组织区域的MPIV，但弹道凝胶没有（P = 0.5814）。在评估模拟材料中位置（下颌骨或上颌骨）的影响时，仅软组织区域存在显著差异。标准差不受模拟材料影响（P > 0.05），但弹道凝胶的变异性最低。
弹道凝胶是最佳的软组织模拟材料，因为它对所有区域的像素强度值影响最小。
