In the treatment of alveolar cleft, imaging evaluation is essential. Panoramic films are often used in evaluation of alveolar cleft before and after the surgery of bone grafting, but there are some shortages of conventional two-dimensional image. Recently, three-dimensional CT was widely used in dental clinic. In the treatment of alveolar cleft, three-dimensional CT can be used in assessment of the size of alveolar cleft, evaluation of the result of bone graft surgery, calculating the volume of bone absorbed after implantation. Compared with spiral CT, cone beam CT has many advantages, such as lower cost, smaller radiation, higher resolution et cetera.
