The results reconstructed with the SART method.

<p>The left column is the reconstructed image, and the right two columns are the profiles along the lines marked in the reconstructed image. The display window for the reconstructed image is [0, 0.5].</p

The reconstructed results with the SART method (the top row), our method (the middle row), and the Brabant method (the bottom row).

<p>The left column is the reconstructed images, and the right two columns are the profiles along the lines marked in the reconstructed images. The display window for the reconstructed images is [0, 0.5].</p

MSE and NMSD of the images shown in Figs 4 and 5.

<p>MSE and NMSD of the images shown in Figs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0144607#pone.0144607.g004" target="_blank">4</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0144607#pone.0144607.g005" target="_blank">5</a>.</p

The photograph of the scanned phantom.

<p>The photograph of the scanned phantom.</p

The results reconstructed with our method (the first and the third rows) and the Brabant method (the second and the fourth rows) from noise free data (the first and the second rows) and noisy data (the third and the fourth rows).

<p>The left column is the reconstructed images, and the right two columns are the profiles along the lines marked in the reconstructed images. The display window for the reconstructed images is [0, 0.5].</p

The results reconstructed with our method from noise free data (the first row) and noisy data (the second row) using error-included x-ray spectrum.

<p>The left column is the reconstructed images, and the right two columns are the profiles along the lines marked in the reconstructed images. The display window for the reconstructed images is [0, 0.5].</p

Numerical phantom for simulation.

<p>Numerical phantom for simulation.</p

dental CBCT data 2

<div>resolution: 512*512*244； unsigned short； a 0.3mm resolution.</div><div><div>This dataset was obtained using the dental CBCT imaging system ZCB100 (Shenzhen ZhongKe TianYue Technology Co., Ltd.) at 110 kV and 10 mAs, with a 15.36-cm FOV</div></div

The estimated spectrum of the x-ray source with voltage 120 kV.

<p>The estimated spectrum of the x-ray source with voltage 120 kV.</p

data from the dental CBCT imaging system ZCB100

<div><br></div><div> These datasets were obtained using the dental CBCT imaging system ZCB100 (Shenzhen ZhongKe TianYue Technology Co., Ltd.).</div