Purpose Three-dimensional (3D) analysis and planning are powerful tools in craniofacial and reconstructive surgery. The elements include 1) analysis, 2) planning, 3) virtual surgery, 4) 3D printouts ...of guides or implants, and 5) verification of actual to planned results. The purpose of this article is to review different applications of 3D planning in craniomaxillofacial surgery. Materials and Methods Case examples involving 3D analysis and planning were reviewed. Common threads pertaining to all types of reconstruction are highlighted and contrasted with unique aspects specific to new applications in craniomaxillofacial surgery. Results Six examples of 3D planning are described: 1) cranial reconstruction, 2) craniosynostosis, 3) midface advancement, 4) mandibular distraction, 5) mandibular reconstruction, and 6) orthognathic surgery. Conclusions Planning in craniomaxillofacial surgery is useful and has applicability across different procedures and reconstructions. Three-dimensional planning and virtual surgery enhance efficiency, accuracy, creativity, and reproducibility in craniomaxillofacial surgery.
Purpose Virtual surgical planning (VSP) can promote efficiency, but the ability to transfer the proposed plan to the actual result has not been adequately studied. The purpose of this study was to ...morphometrically compare the virtually preplanned scenario with the postoperative 3-dimensional (3D) anatomic result. Materials and Methods A retrospective review of 10 patients who underwent mandibular reconstruction using a free fibula flap and VSP were evaluated. Pre- and postoperative Digital Imaging and Communications in Medicine files were imported into Mimics 10.01 software (Materialise, Leuven, Belgium) for surgical planning. Preoperative VSP and 1-week postoperative computed tomographic (CT) scans were evaluated to assess surgical accuracy using VSP. The pre- and postoperative morphometric measurements were compared using the Student t test. Results Twenty CT scans from 10 patients (mean age, 56.9 ± 20.2 yr) who underwent partial mandibular resection were analyzed. The dimensions of the fibula segments after osteotomy showed no difference from the preoperative VSP (mean difference in fibula height, 1.2 mm; mean difference in width, 0.9 mm; mean difference in length, 1.3 mm). The postoperative anterior and posterior mandibular angles differed from the VSP by 12.4° and −12.5°, respectively. The condylar distance and inclination showed a discrepancy of only 1.7 mm and 4.6°, respectively, between VSP and postoperative CT scans. Conclusions VSP confers reproducible precision and accuracy for free fibular mandibular reconstruction. The benefit was most striking for large reconstructions requiring multiple fibular segments. Future directions include assessing the use of external registration devices to enhance surgical accuracy and to follow patients longitudinally to monitor the long-term benefit of VSP.
Purpose The impact of surgically assisted maxillary expansion (SAME) on facial soft tissue structures has not been adequately studied using 3-dimensional (3D) objective analysis. The purpose of this ...study was to analyze nasolabial soft tissue after SAME using 3D photographic technology. Materials and Methods This was a retrospective cohort study of patients undergoing SAME in which pre- and postexpansion 3D photographs (3D VECTRA Photosystem, Canfield, Fairfield, NJ) were analyzed. Nasolabial anthropometric measurements were performed using the 3D postprocessing software (Mirror). A follow-up period of at least 6 months was required for final evaluation. Two observers verified the landmarks on each dataset before measuring. Statistical analysis involved the paired t test, the Simes correction for multiple comparisons, and repeated measures analysis of covariance (ANCOVA) to control for age, gender, and the time lag between pre- and postoperative assessments. Results Twelve patients (24 photogrammetric datasets) were included. The male-to-female ratio was 0.5 (mean age, 17.3 yr). Nasal changes after SAME showed significant increases ( P < .05) in alar width (from 33.1 to 34.5 mm), sill width (from 9.2 to 9.7 mm), and columella projection (from 94.1 to 95.1 mm) after the Simes correction. ANCOVA showed a significant increase in alar base width. Distinct changes in nostril shape and dimension were found, but lacked statistical significance. Conclusion Three-dimensional analysis shows widening of the alar width and alar base width after SAME. The magnitude of nasal change parallels that of expansion at the piriform aperture.
Access to the mandibular angle for removal of pathology poses a unique challenge to surgeons. Intraoral approaches result in considerable bone removal and potential damage to the inferior alveolar ...nerve (IAN). Extraoral approaches are associated with a cutaneous scar and the potential for facial nerve damage. This report describes the case of a 53-year-old man with a deeply impacted third molar associated with a cystic lesion that was treated by enucleation using an intraoral sagittal split osteotomy. This approach allowed for complete access and visualization of the cyst and displaced third molar and protection of the IAN with minimal surgical morbidity.
Purpose Temporomandibular joint malformation is a complex deformity in Treacher-Collins syndrome (TCS); however, it is not well characterized. This study aimed to better clarify this pathology by ...volumetrically assessing the mandibular condyle in patients with TCS compared with normal controls and the relative contribution of the condyle to hemimandibular volume. Materials and Methods A retrospective, cross-sectional analysis of pediatric patients with TCS and unaffected controls was performed. The study sample was comprised of Treacher Collins patients. The predictor variable in this study was disease status (TCS diagnosis vs control), and the outcome variable was condylar volume. Demographic information was collected, and 3-dimensional computed tomographic data were analyzed by computerized segmentation (Materialise). Volumes were obtained for TCS condyles and compared with age-matched controls using the Student t test. Results Three-dimensional computed tomographic scans were identified in 10 patients with TCS (20 sides) and 14 control subjects (28 sides). The TCS group included 4 female and 6 male patients (age, 0.3 to 213 mo; average age, 66.5 mo). The control cohort included 7 female and 7 male subjects (average age, 68.8 mo). Evaluation of the mandibular condyle showed that patients with TCS had a significantly smaller condylar volume than control patients (TCS, 178.28 ± 182.74 mm3 ; control, 863.55 ± 367.20 mm3 ; P < .001). Additional intragroup analysis showed no significant differences between the left and right condylar volumes in the TCS group ( P = .267). In addition, the condyle for patients with TCS represented a smaller proportion of hemimandibular volume compared with controls (1.37% vs 4.19%, respectively; P < .001). Conclusions The results of the this study suggest that condylar volumes are significantly smaller in patients with TCS compared with age-matched controls, and the condyle represents a smaller fraction of the total mandibular volume for patients with TCS than in unaffected children. In addition, there is considerable variability of condylar size in patients with TCS. These facts portend treatment decisions because a functional temporomandibular joint is necessary and may need to be reconstructed as a first stage before effective implementation of distraction procedures.
Purpose Strategies to address severe anteroposterior palatal shortening with velopharyngeal insufficiency include palatal lengthening or manipulation of posterior pharyngeal tissue as a flap or ...sphincter. In some cases, a single procedure alone is not sufficient to achieve dynamic velopharyngeal closure. The objective of this study was to determine whether double-opposing Z-plasty coupled with a posterior pharyngeal flap would achieve adequate palatal length in severe velopharyngeal dysfunction. Materials and Methods Six patients, 3 with previously unrepaired cleft palate and 3 children with previous straight-line repairs and significant anteroposterior shortening, were included. Demographic and perioperative information was tabulated. Subjective and objective speech data were gathered, if available. Complications, follow-ups, and postoperative nasometric results were compiled. Statistical analysis involved the paired t test. Results There were no perioperative complications. Follow-up was at least 1 year. No postoperative fistulas or nasal obstruction developed. Hypernasal speech and nasal emission were subjectively improved in all patients. Nasometric data showed a statistically significant improvement in nasal air escape with speech. Conclusions Simultaneous double-opposing Z-plasty and posterior pharyngeal flap can be performed effectively. This strategy is useful for severe velopharyngeal dysfunction secondary to anteroposterior palatal shortening or a previously unrepaired cleft palate, and the technique optimizes palatal function and creates a mechanical blockade to nasal air escape.
Abstract Purpose Virtual surgical planning (VSP) using computer-aided design and manufacturing (CAD-CAM) have been reported to aid in craniofacial reconstruction. The reported improvements have been ...mainly related to operative performance, with limited evaluations of the position and function of the temporomandibular joint (TMJ). This study analyzed the radiographic detail of postoperative outcomes related to the TMJ. Methods Patients who underwent mandibular reconstruction with and without VSP were analyzed. All patients underwent preoperative computed tomography (CT) of their mandible. In the VSP group, CAD/CAM planning was performed preoperatively using CT DICOM data. Postoperative CT’s from both groups were quantitatively compared to evaluate the TMJ. CT images were digitized for 2D and 3D analysis using surgical planning software (Materialise, Leuven, Belgium). Anatomical landmarks and cephalometric relationships were analyzed. Results 16 patients who underwent either traditional or VSP for mandibular reconstruction were compared. Two groups (n=8 each) were compared for positioning of the mandibular condyle in the glenoid fossa. Measurements of superior, anterior and lateral movements were comparable in the pre- and post-operative groups for both the traditional and VSP groups (ANOVA p<0.001). Sub-group analysis evaluating ipsilateral changes in the mandibular condyle position for traditional vs VSP noted decreased percentage of change in superior (22 vs 10%, p<0.1), anterior (32 vs 15%, p<0.1) and lateral shift (7 vs 1%, NS) of the condyle for left mandibular reconstructions (n=8). Ipsilateral right mandible reconstruction (n=6) demonstrated changes in superior (62 vs 15%, p<0.1) and anterior shift (5 vs 9%, NS). Conclusion Our data demonstrate comparable pre and postoperative positions of the TMJ for both traditional and virtual surgically planned mandibular reconstructions. Evaluation of condyle movements showed differences in ipsilateral position in pre- and postoperative groups. VSP resulted in decreased superior and lateral shift of the ipsilateral condyle, and a decreased change in the condylar and condylar neck angles. This work demonstrates that virtual surgical planning can lead to increased precision in reconstruction leading to preserved normative anatomical relationships.
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