Backscatter image mosaics frequently suffer from noticeable visual artifacts and missing regions, which reduce the performance of subsequent feature extraction or classification processes. In this paper, a new fusion-based method for the restoration of bathymetric side-scan backscatter images is presented. First, the values of missing backscatter pixels are estimated using contextual information provided by the underlying bathymetry mesh. As a final step, a histogram regularization process is performed to remove intensity artifacts caused by inaccurate compensation of sensor gain. Restoration results are presented for Simrad EM12S images.