Authors’ response

We appreciate the interest of Drs Ye, Li, and Lai in the controversial topic of airway volume assessment with CBCT. Below are our responses to their questions.

The aim of our study was the comparison between the scanned and actual volumes from the prototype airway. The choice of a negative prototype to create an airway model was because the Dolphin software only allows the volume measurement of empty areas. We did not expect to mimic the soft tissues surrounding the airway.

We did not intend to establish a protocol for airway assessment but to determine the most accurate threshold for airway volume calculation with specific experimental conditions. So, it was not our objective to extend our results to the measurement of in-vivo CBCT scans but to raise the question of the great difference that can arise from volume calculations with different thresholds. Unfortunately, it is not possible to do this research in humans.

The description of the scan protocol (milliamperes, kilovolts) used by CBCT machines is important in studies that evaluate airway volume. Several studies have evaluated airway volumes with different CBCT machines. Therefore, we emphasized in the discussion that our study was based on specific experimental conditions.

For this investigation, we used only 1 subject to obtain the airway prototype. Future investigations about the comparison between the airway volumes from several subjects and the actual volumes of the prototypes obtained from these subjects will allow the establishment of the most appropriate threshold value to use with Dolphin software for airway volume assessment.


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Apr 8, 2017 | Posted by in Orthodontics | Comments Off on Authors’ response
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