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Objective Maxillary anterior segmental distraction osteogenesis (MASDO) for cleft and palate patients is the alternative treatment option to correct malocclusion with maxillary arch deficiency and severe crowding. After MASDO, prosthetic considerations are crucial for patients with cleft lip and palate because it is related to facial esthetics and occlusal function. The objectives of this study were to investigate the final restoration type for created alveolar space by MASDO. Methods Thirteen patients with cleft lip and palate who underwent MASDO and orthodontic treatment from the years 2000 to 2010 in Yonsei University were examined. Final restorations are classified as dental implants, conventional prosthesis, and orthodontic space closure. The relationship between the distracted areas and final restoration type was investigated. The authors evaluated lateral cephalograms obtained at predistraction osteogenesis (pre-DO; T1), postdistraction osteogenesis (post-DO; T2), and debond (T3), and measured changes from T1 to T2 and from T2 to T3. Results There was no significant difference of final restoration percentage of dental implants, conventional prosthesis, and space closure with orthodontic treatment. However, dental implants and conventional prostheses were applied more frequently in the posterior area and in the anterior area, respectively. The relapse rate was observed as 36.7% and 22.4% in the values of N-A distance and ANB angulation in T2-T3 stage. Conclusion The MASDO site should be decided, based on final restoration goal. Among the created alveolar spaces, implants were applied mainly to the posterior site and the conventional prostheses were mostly restored to the anterior site. For space closure by orthodontic approach, the area could be both anterior or posterior.

Purpose This study was performed to evaluate the dimensional accuracy of digital dental models constructed from cone-beam computed tomographic (CBCT) scans of polyvinyl siloxane (PVS) impressions and cast scan models. Materials and Methods A pair of PVS impressions was obtained from 20 subjects and scanned using CBCT (resolution, 0.1 mm). A cast scan model was constructed by scanning the gypsum model using a model scanner. After reconstruction of the digital models, the mesio-distal width of each tooth, inter-canine width, and inter-molar width were measured, and the Bolton ratios were calculated and compared. The 2 models were superimposed and the difference between the models was measured using 3-dimensional analysis. Results The range of mean error between the cast scan model and the CBCT scan model was −0.15 mm to 0.13 mm in the mesio-distal width of the teeth and 0.03 mm to 0.42 mm in the width analysis. The differences in the Bolton ratios between the cast scan models and CBCT scan models were 0.87 (anterior ratio) and 0.72 (overall ratio), with no significant difference (P>0.05). The mean maxillary and mandibular difference when the cast scan model and the CBCT scan model were superimposed was 53 µm. Conclusion There was no statistically significant difference in most of the measurements. The maximum tooth size difference was 0.15 mm, and the average difference in model overlap was 53 µm. Digital models produced by scanning impressions at a high resolution using CBCT can be used in clinical practice.