Background: The aim of this study was to investigate whether a complementary Cone-Beam Computed Tomography (CBCT) in patients with Cleft Lip and Palate (CLP) after alveolar bone-grafting to clefts gave substantial additional information, and particularly whether such new information had any implications for the further care of the patients.

Methods: Seventeen children, with complete CLP, 10 unilateral and seven bilateral clefts, in all 24 clefts, were evaluated six months after secondary alveolar bone-grafting with two-dimensional intra-oral radiographs complemented with CBCT. The mean age at bone-grafting was 8.8 years. Three different examiners evaluated the radiographic documentation.

Results: The mean pre-operative cleft width was 5.8mm. In 15 of the 24 clefts the same interpretation was made on both two-dimensional radiographs and CBCT. In the remaining nine clefts, CBCT added important information to the treatment decision.

Conclusions: For the evaluation six months post-operatively of the success of alveolar bone-grafting to clefts, the two-dimensional radiograph should be complemented with CBCT unless the two-dimensional radiograph without doubt reveals open residual cleft and clinical findings indicate graft failure.