In Endodontics, dentists need a good visualization of dental root canals as found in Cone Beam Computed Tomography (CBCT) dental volumes to diagnose and prevent the development of some anomalies. These CBCT dental volumes, however, suffer from low resolution. In order, to enhance their resolution, we need to apply a super-resolution technique. In this paper, we propose a new 3D super resolution algorithm based on a linear model, consisting of a blurring operator and a decimation operator, which is an extension of Zhao’s work [1] in 3D, taking the low-resolution volume as an input and producing the high-resolution volume as an output. We present a generalization of the 2D Super-Resolution problem into a 3D Super- Resolution problem as we apply it to 3D dental volume. Our new Super-Resolution algorithm as applied to dental CBCT volumes is a direct method aiming to get the exact solution with a short computation time. Results show an improvement in the resolution of the CBCT in a short time in comparison with Zhao’s work, which was applied to CBCT dental volumes slice by slice, [2].