Received: 25 January 2019
Accepted: 19 February 2019
First Online: 11 March 2019
Ethics approval and consent to participate
: The postoperative MDCT examination including assessment of maxillary sinus mucosa was thoroughly explained before the examination, and written consent was obtained from all patients. This study was approved by the Tokyo Dental College Institutional Review Board (Ethics Review Board Approval Number 803), and all participants provided their written, informed consent.
: For all patients, we have obtained written agreement on the use of CT images. Also, we are careful not to identify individuals from images and data.
: The authors declare that they have no competing interests.
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