Purpose The purpose of this study was to determine whether the surgical outcomes achieved with computer-aided surgical simulation (CASS) are better than those achieved with traditional methods. ...Materials and Methods Twelve consecutive patients with craniomaxillofacial (CMF) deformities were enrolled. According to the CASS clinical protocol, a 3-dimensional computer composite skull model for each patient was generated and reoriented to the neutral head posture. These models underwent 2 virtual surgeries: 1 was based on CASS (experimental group) and the other was based on traditional methods 1 year later (control group). Once the 2 virtual surgeries were completed, 2 experienced oral and maxillofacial surgeons at 2 different settings evaluated the 2 surgical outcomes. They were blinded to the planning method used on the virtual models and each other's evaluation results. The primary outcome was overall CMF skeletal harmony. The secondary outcomes were individual maxillary, mandibular, and chin harmonies. Statistical analyses were performed. Results Overall CMF skeletal harmony achieved with CASS was statistically significantly better than that achieved with traditional methods. In addition, the maxillary and mandibular surgical outcomes achieved with CASS were significantly better. Furthermore, although not included in the statistical model, the chin symmetry achieved by CASS tended to be better. A regression model was established between mandibular symmetry and overall CMF skeletal harmony. Conclusion The surgical outcomes achieved with CASS are significantly better than those achieved with traditional planning methods. In addition, CASS enables the surgeon to better correct maxillary yaw deformity, better place proximal/distal segments, and better restore mandibular symmetry. The critical step in achieving better overall CMF skeletal harmony is to restore mandibular symmetry.
Purpose The purpose of this study was to evaluate the clinical feasibility of a new method to orient 3-dimensional (3D) computed tomography models to the natural head position (NHP). This method uses ...a small and inexpensive digital orientation device to record NHP in 3 dimensions. This device consists of a digital orientation sensor attached to the patient via a facebow and an individualized bite jig. The study was designed to answer 2 questions: 1 ) whether the weight of the new device can negatively influence the NHP and 2 ) whether the new method is as accurate as the gold standard. Patients and Methods Fifteen patients with craniomaxillofacial deformities were included in the study. Each patient's NHP is recorded 3 times. The first NHP was recorded with a laser scanning method without the presence of the digital orientation device. The second NHP was recorded with the digital orientation device. Simultaneously, the third NHP was also recorded with the laser scanning method. Each recorded NHP measurement was then transferred to the patient's 3D computed tomography facial model, resulting in 3 different orientations for each patient: the orientation generated via the laser scanning method without the presence of the digital orientation sensor and facebow (orientation 1), the orientation generated by use of the laser scanning method with the presence of the digital orientation sensor and facebow (orientation 2), and the orientation generated with the digital orientation device (orientation 3). Comparisons are then made between orientations 1 and 2 and between orientations 2 and 3, respectively. Statistical analyses are performed. Results The results show that in each pair, the difference (Δ) between the 2 measurements is not statistically significantly different from 0°. In addition, in the first pair, the Bland-Altman lower and upper limits of the Δ between the 2 measurements are within 1.5° in pitch and within a subdegree in roll and yaw. In the second pair, the limits of the Δ in all 3 dimensions are within 0.5°. Conclusion Our technique can accurately record NHP in 3 dimensions and precisely transfer it to a 3D model. In addition, the extra weight of the digital orientation sensor and facebow has minimal influence on the self-balanced NHP establishment.
Summary Gardner's syndrome (GS) is a hereditary autosomal dominant disease of the colon that presents with extra-colonic manifestations such as osteomas, skin lesions and dental abnormalities. ...Osteomas are commonly found in the skull, jaws and the paranasal sinuses. We present a family of four sisters affected with GS with a wide range of anomalies. The role of Cone beam computed tomography (CBCT) in the early detection and evaluation of osteomas and dental anomalies with precise assessment of their relationship to adjacent anatomic structures is described here in detail. The careful interpretation of CBCT may be of a great value in surgical and orthodontic treatment planning in the presence of jaw lesions. Management of dental problems in GS may be challenging due to the presence of odontomas and increased bone density. A multidisciplinary approach in the management of GS can achieve the best treatment results.
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