Martin Bengtsson1, Gert Wall2, Lennart Greiff3, Lars Rasmusson4. 1. Department of Oral & Maxillofacial Surgery, The University Hospital of Skåne, Lund, Sweden; Department of Oral & Maxillofacial Surgery, The Sahlgrenska Academy, Gothenburg University, Sweden. Electronic address: martin.n.bengtsson@skane.se. 2. Department of Oral & Maxillofacial Surgery, The University Hospital of Skåne, Lund, Sweden. 3. Department of Otolaryngology, The University Hospital of Skåne, Lund, Sweden. 4. Department of Oral & Maxillofacial Surgery, The Sahlgrenska Academy, Gothenburg University, Sweden.
Abstract
PURPOSE: The aim of the present study was to compare the accuracy of two-dimensional (2D) and three-dimensional (3D) prediction methods. The hypothesis was that a 3D technique would give a more accurate outcome of the postoperative result. MATERIAL AND METHODS:Patients with severe class III occlusion were included and planed with both a 2D and 3D prediction technique. They were there after randomly subdivided into a control (2D) and test (3D) group and treated according to the technique randomized for. Cephalometric measurements from 2D and 3D predictions were compared with 12-month follow-up respectively. Together with an analysis of tracing error, placements of 3580 cephalometric markers, 2460 measurements, 680 intra-individual analyses and 1200 preop/postop comparisons were performed in 57 individuals. RESULTS: Statistically significant differences for accuracy between the two groups were seen for 11/NSL-112/NSL2 and for A-A2 (p < 0.05). Both groups showed a high level of accuracy for SNA and SNB. The test group also showed a relatively high level of accuracy for 11/NSL and for the A-point. No prediction method achieves a perfect accuracy. As expected from this, measuring accuracy within each group showed statistically significant difference for all markers and cephalometric measurements (p < 0.001). Mandibular markers showed greater differences than maxillary markers. CONCLUSION: The present study indicates an equal high accuracy in predicting facial outcome for both studied techniques. However, in patients with asymmetry the three-dimensional technique has an obvious advantage.
RCT Entities:
PURPOSE: The aim of the present study was to compare the accuracy of two-dimensional (2D) and three-dimensional (3D) prediction methods. The hypothesis was that a 3D technique would give a more accurate outcome of the postoperative result. MATERIAL AND METHODS:Patients with severe class III occlusion were included and planed with both a 2D and 3D prediction technique. They were there after randomly subdivided into a control (2D) and test (3D) group and treated according to the technique randomized for. Cephalometric measurements from 2D and 3D predictions were compared with 12-month follow-up respectively. Together with an analysis of tracing error, placements of 3580 cephalometric markers, 2460 measurements, 680 intra-individual analyses and 1200 preop/postop comparisons were performed in 57 individuals. RESULTS: Statistically significant differences for accuracy between the two groups were seen for 11/NSL-112/NSL2 and for A-A2 (p < 0.05). Both groups showed a high level of accuracy for SNA and SNB. The test group also showed a relatively high level of accuracy for 11/NSL and for the A-point. No prediction method achieves a perfect accuracy. As expected from this, measuring accuracy within each group showed statistically significant difference for all markers and cephalometric measurements (p < 0.001). Mandibular markers showed greater differences than maxillary markers. CONCLUSION: The present study indicates an equal high accuracy in predicting facial outcome for both studied techniques. However, in patients with asymmetry the three-dimensional technique has an obvious advantage.