Shahriar Shahab; Amirfarhang Miresmaeili; Mehdi Esmaeili; Vahid Mollabashi; Nasrin Farhadian
Abstract
Aim: The main objective of this preliminary study was to introduce a new approach for the estimation of nasal cavity volume using two dimensional measurements in serial sections, as an alternative to planimetry volume measurements.
Materials and Methods: Ten CBCT images were studied in the coronal plane ...
Read More
Aim: The main objective of this preliminary study was to introduce a new approach for the estimation of nasal cavity volume using two dimensional measurements in serial sections, as an alternative to planimetry volume measurements.
Materials and Methods: Ten CBCT images were studied in the coronal plane and the 4-mm thick sections were selected between Anterior and Posterior Nasal Spine. Real estimation of nasal cavity volume was computed using Cavalieri principle in conjunction with planimetry method. The outline of each slice was digitized and the resulted surface area was computed by AutoCAD software. In alternative method, a surface area estimate was measured by multiplying maximum width and maximum height in each slice. The sum of slices area in each method was named as Total Nasal Cavity Area (TNCA). Nasal cavity volume = TNCA × thickness of tomography slice. TNCA1 based on planimetry method, was compared with TNCA2 using to coordinates with linear regression analysis.Results: Regression analysis showed a powerful correlation between two methods measurements (r = 0.951). The following formula was proposed for volume estimation using the coordinate method: TNCA1 = 85.6±1.53 TNCA2.
Conclusions: In this pilot study, we substituted successfully two linear measurements instead of planimetry to estimate nasal cavity volume. This may help investigators to overcome inherent problems appearing in measurements of nasal cavity volume.
Amirfarhang Miresmaeili; Shahriar Shahab; Faezeh Yousefi; Vahid Mollabashi
Abstract
Aim: Tooth size in panoramic view has both magnification and distortion. It is supposed that panoramic view generated from Cone Beam computed tomography (CBCT) has more accurate tooth size compared with conventional panoramic view. The purpose of this study was to compare magnification of mandibular ...
Read More
Aim: Tooth size in panoramic view has both magnification and distortion. It is supposed that panoramic view generated from Cone Beam computed tomography (CBCT) has more accurate tooth size compared with conventional panoramic view. The purpose of this study was to compare magnification of mandibular tooth size in digital panoramic radiographs andCBCT reconstructed panoramic images.
Materials and Methods: Amongpatients referred to Hamadan dental school, having both digital panoramic radiograph and CBCT, 28 patients were selected. Maximum width and length of mandibular teeth No. 36,34,33,31,41,43,44, 46 were measured in digital panoramic views and in CBCT reconstructed panoramic views. The CBCT images in multiple planes were used to give the dimensions referred to as gold standard. MANOVA test, Post Hoc and Tukey were used for statistical analysis.Results: There was a significant difference in width and length of teeth between digital panoramic view and both reconstructed panoramic view and gold standard (P value< 0.05). In digital panoramic view the maximum and minimum of magnification was observed in incisors and molar teeth respectively. There were no statistical differences in width and length measurements between reconstructed panoramic view and gold standard except for magnification in incisor teeth width (P value> 0.05). Conclusion: CBCT reconstructed panoramic views show significantly less magnification regarding tooth size compared with digital panoramic views.
