Average Three-Dimensional Skeletofacial Model as a Template for Bone Repositioning during Virtual Orthognathic Surgery.

BACKGROUND: Virtual planning has revolutionized orthognathic surgery. This study presents a computer-assisted method for constructing average three-dimensional skeletofacial models that can be applied as templates for surgical planning for maxillomandibular repositioning. METHODS: The authors used the images of 60 individuals (30 women and 30 men) who had never undergone orthognathic surgery to construct an average three-dimensional skeletofacial model for male participants and one for female participants. The authors validated the accuracy of the newly developed skeletofacial models by comparing their images with 30 surgical simulation images (ie, skulls) that had been created using three-dimensional cephalometric normative data. The comparison was conducted by superimposing surgical simulation images created using the authors' models with the previously created images to analyze their differences, particularly differences in the jawbone position. RESULTS: For all participants, the authors compared the jaw position in the surgical simulation images created using the authors' average three-dimensional skeletofacial models with that in the images created using three-dimensional cephalometric normative data. The results revealed that the planned maxillary and mandibular positions were similar in both images and that the differences between all facial landmarks were less than 1 mm, except for one dental position. Most studies have reported less than 2 mm to be the success criterion for the distance difference between planned and outcome images; thus, the authors' data indicate high consistency between the images in terms of jawbone position. CONCLUSION: The authors' average three-dimensional skeletofacial models provide an innovative template-assisted orthognathic surgery planning modality that can enhance the fully digital workflow for virtual orthognathic surgical planning. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Optimizing Orthognathic Surgery: Leveraging the Average Skull as a Dynamic Template for Surgical Simulation and Planning in 30 Patient Cases.

Virtual planning has revolutionized orthognathic surgery (OGS), marking a significant advancement in the field. This study aims to showcase the practical application of our established 3D average skull template as a guiding framework for surgical planning, and to share valuable insights from our clinical experience. We enrolled 30 consecutive Taiwanese patients (18 females and 12 males) who underwent two-jaw orthognathic surgery with surgical simulation, utilizing the average skull template for planning. Results indicate the method's applicability and precision. By adhering to the surgical plan, post-operative outcomes closely aligned with the average skull template, showing negligible deviations of less than 2 mm. Moreover, patients expressed high satisfaction with post-surgery facial changes, with the chin appearance receiving the highest satisfaction scores, while the lowest scores were attributed to nose appearance. Notably, the substantial change in lower jaw position post-mandibular setback surgery contributed to increased satisfaction with the chin position. In conclusion, this study does not seek to replace established surgical planning methods, but underscores that utilizing an average skull as a surgical design template provides a viable, accurate, and efficient option for OGS patients.

Single-Splint, 2-Jaw Orthognathic Surgery for Correction of Facial Asymmetry: 3-Dimensional Planning and Surgical Execution.

Three-dimensional (3D) planning of orthognathic surgery (OGS) improves the treatment of facial asymmetry and malocclusion, but no consensus exists among clinicians regarding technical details. This study verified the consistency of authors' workflow and strategies between 3D planning and surgical execution for facial asymmetry. This retrospective study recruited consecutive patients (n=54) with nonsyndromic facial asymmetry associated with malocclusion. The stepwise workflow included orthodontic treatment, 3D imaging-based evaluation, planning, and transferring the virtual of single-splint 2-jaw OGS to actual surgery in all patients. Seven landmark-based measurements were selected for postoperative assessment of facial symmetry. Fifty patients had no anesthetic/surgical-related episode and procedure-related complications. Others experienced wound infection (n=1), transient TMJ discomfort (n=1), and facial numbness (n=3). Two cases had minor residual asymmetry (cheek and chin, respectively), but did not request revisionary bone or soft tissue surgery. Comparisons between the planned and postoperative 3D images with quantitative measurement revealed acceptable outcome data. The results showed a significant increase in facial symmetry at 7 landmark-based postoperative measurements for both male and female. This 3D-assisted pathway of OGS permitted achievement of consistent satisfactory results in managing facial asymmetry, with low rate of complications and secondary management.

Applications of three-dimensional imaging techniques in craniomaxillofacial surgery: A literature review.

Three-dimensional (3D) imaging technologies are increasingly used in craniomaxillofacial (CMF) surgery, especially to enable clinicians to get an effective approach and obtain better treatment results during different preoperative and postoperative phases, namely during image acquisition and diagnosis, virtual surgical planning (VSP), actual surgery, and treatment outcome assessment. The article presents an overview of 3D imaging technologies used in the aforementioned phases of the most common CMF surgery. We searched for relevant studies on 3D imaging applications in CMF surgery published over the past 10 years in the PubMed, ProQuest (Medline), Web of Science, Science Direct, Clinical Key, and Embase databases. A total of 2094 articles were found, of which 712 were relevant. An additional 26 manually searched articles were included in the analysis. The findings of the review demonstrated that 3D imaging technology is becoming increasingly popular in clinical practice and an essential tool for plastic surgeons. This review provides information that will help researchers and clinicians consider the use of 3D imaging techniques in CMF surgery to improve the quality of surgical procedures and achieve satisfactory treatment outcomes.

Implementation of an Attention Mechanism Model for Facial Beauty Assessment Using Transfer Learning.

An important consideration in medical plastic surgery is the evaluation of the patient's facial symmetry. However, because facial attractiveness is a slightly individualized cognitive experience, it is difficult to determine face attractiveness manually. This study aimed to train a model for assessing facial attractiveness using transfer learning while also using the fine-grained image model to separate similar images by first learning features. In this case, the system can make assessments based on the input of facial photos. Thus, doctors can quickly and objectively treat patients' scoring and save time for scoring. The transfer learning was combined with CNN, Xception, and attention mechanism models for training, using the SCUT-FBP5500 dataset for pre-training and freezing the weights as the transfer learning model. Then, we trained the Chang Gung Memorial Hospital Taiwan dataset to train the model based on transfer learning. The evaluation uses the mean absolute error percentage (MAPE) value. The root mean square error (RMSE) value is used as the basis for experimental adjustment and the quantitative standard for the model's predictive. The best model can obtain 0.50 in RMSE and 18.5% average error in MAPE. A web page was developed to infer the deep learning model to visualize the predictive model.

Long-Term Outcome of Primary Rhinoplasty with Overcorrection in Patients with Unilateral Cleft Lip: Avoiding Intermediate Rhinoplasty.

BACKGROUND: No consensus exists regarding the timing or technique of rhinoplasty for correction of the unilateral cleft lip nose deformity, with few studies examining the long-term effects of a single technique. This study appraised the long-term outcomes of primary rhinoplasty using the Tajima technique for overcorrection in a cohort of patients with unilateral cleft lip nose deformity after attaining skeletal maturity. METHODS: Consecutive nonsyndromic patients with unilateral cleft lip nose deformity ( n = 103) who underwent primary rhinoplasty with overcorrection by a single surgeon between 2000 and 2005 were reviewed. Patients with unilateral cleft lip and nasal deformity who underwent primary rhinoplasty (but with no overcorrection) ( n = 30) and noncleft individuals ( n = 27) were recruited for comparison. Outcomes were assessed through FACE-Q scales evaluating satisfaction with appearance of nose and nostrils (two scales) and computer-based objective photogrammetric analysis of nasal symmetry (nostril height, nostril width, nostril area, alar height, and alar width parameters). RESULTS: Significant differences (all P < 0.001) were observed between the Tajima and non-Tajima groups for all but one photogrammetric nasal parameter (nostril area), with the Tajima group demonstrating closer mean values to the noncleft group. The Tajima and noncleft groups demonstrated no significant difference (all P > 0.05) for scores of FACE-Q nose and nostrils scales. CONCLUSION: This study indicated that the patients who underwent primary rhinoplasty with overcorrection had improved results with no necessity for intermediate rhinoplasty, emphasizing that the procedure is an effective approach to correct the unilateral cleft nose deformity. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Favorable Transverse Maxillary Development after Covering the Lateral Raw Surfaces with Buccal Fat Flaps in Modified Furlow Palatoplasty: A Three-Dimensional Imaging-Assisted Long-Term Comparative Outcome Study.

BACKGROUND: The pedicled buccal fat flap has recently been applied to cover the lateral raw surfaces during palatoplasty as an attempt to mitigate scar-induced transverse maxillary constriction during growth, but with no formal long-term comparative analysis. This three-dimensional imaging-assisted study assessed its impact on posterior transverse maxillary development. METHODS: Cone beam computed tomographic scans from patients with unilateral cleft lip, alveolus, and palate who received buccal fat flap (buccal fat group; n = 22) or Surgicel (Surgicel group; n = 32) for covering lateral raw surfaces during modified Furlow palatoplasty at 9 to 10 months of age and had reached the age of 9 years were retrieved for analysis. Patients with unilateral cleft lip and alveolus (nonpalatoplasty group; n = 24) were also included for comparison. Using three-dimensional maxillary image models, linear (U6T-MSP and U6J-MSP) and area measurements were calculated for cleft and noncleft posterior maxillary sides and for total posterior transverse maxillary dimension. RESULTS: The buccal fat group had significantly (all p < 0.05) wider dimensions compared with the Surgicel group for all transverse maxillary measurements on both the cleft and noncleft sides, except for U6J-MSP and posterior palatal area parameters on the cleft side ( p > 0.05). The buccal fat group had significantly (all p < 0.05) wider total transverse maxillary dimensions compared with the Surgicel and nonpalatoplasty groups. CONCLUSION: Covering the lateral raw surfaces with buccal fat flaps resulted in less posterior transverse maxillary constriction compared with the Surgicel-based covering procedure. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Bone marrow plasma level of decorin may be associated with improved treatment outcomes in a subset of multiple myeloma patients.

BACKGROUND/PURPOSE: Decorin is a small leucine-rich proteoglycan rich in extracellular matrix with potential antitumor activity. However, the role of decorin in hematological malignancies remains unclear, especially in the case of multiple myeloma (MM), a bone marrow (BM) stroma-dependent plasma cell neoplasm. METHODS: We measured decorin levels in BM plasma samples from 270 patients with newly diagnosed MM (NDMM) using enzyme-linked immunosorbent assays. RESULTS: Patients were divided into high decorin (H-DCN, > 18.99 ng/mL) and low decorin (L-DCN <9.76 ng/mL) groups. Patients in the H-DCN group had more advanced-stage disease, including more osteolysis terms of higher levels of C-terminal telopeptides of type I collagen (0.69 ± 0.55 vs. 0.49 ± 0.36 ng/mL; P = 0.028), than those in the L-DCN group. Decorin levels correlated positively with hepatocyte growth factor (HGF) levels in BM plasma samples from NDMM patients (Pearson correlation coefficient, 0.226; P < 0.001). Patients with low HGF (<0.79 ng/mL) but high decorin levels (≥12.95 ng/mL) had a higher treatment response rate (90.5% vs. 54.5%, respectively; P = 0.015) and improved overall survival (not reached vs. 53 months; P = 0.0148) than those with lower decorin levels (<12.95 ng/mL). Multivariate analysis confirmed that a high decorin level was an independent predictive factor for treatment response and survival in patients with low HGF levels. CONCLUSION: Our findings suggest that decorin may exert protective effects in this subset of MM patients.

Aesthetic Enhancement of the Vermilion Using Dermofat Graft in Patients With Cleft Lip Deformity.

BACKGROUND: There is an increasing patient expectation for better esthetics, manifesting through anatomical harmony, projection, and volume of the upper lip relative to the lower lip, in patients with cleft deformity. The aim of this study is to investigate the outcome of vermilion augmentation using autologous dermofat graft (DFG) to enhance the lip using both quantitative and qualitative assessment. METHODS: Patients with secondary cleft lip deformity who received the surgical treatment in our institution from 2015 to 2018 were recruited. Panel assessment was performed on standardized preoperative and postoperative digital photographs. A patient questionnaire was used for the reported outcome. Image processing and analyses were applied to measure the lip change. Statistical analyses were performed. RESULTS: A total of 91 patients were included. The mean age at operation was 22.7 years, and postoperative follow-up was 3.6 years. There were no complications in the study group. The panel assessment showed significant improvement (P < .00001) on upper lip vermilion in both frontal and lateral profile views. Ninety-five percent of patients reported improvement of the upper lip projection and volume. Quantitative image analysis showed an increase in the upper lip vermilion ratio in 97% of the cases in frontal views and improvement of the vermilion projection in 87% of the cases in the superimposed lateral views. CONCLUSIONS: The use of DFG is an effective and reproducible method for vermilion augmentation and aesthetic enhancement in patients presenting with upper lip insufficiency relative to the lower lip.

Outcome of full digital workflow for orthognathic surgery planning in the treatment of asymmetric skeletal class III deformity.

BACKGROUND/PURPOSE: Studies have reported the advantages of digital imaging-assisted orthognathic surgery planning, but there is scarce information about a full digital planning modality. This study evaluated the 3D cephalometric-based and patient-reported outcomes of a full digital workflow for orthognathic surgery planning in the treatment of asymmetric maxillomandibular disharmony. METHODS: A postoperative 3D image dataset of 30 Taiwanese Chinese patients with asymmetric skeletal Class III deformities who underwent full digital planning for two-jaw surgery were retrieved from the authors' database. The 3D cephalometric data (dental, skeletal, and soft tissue evaluations) were compared to the ethnicity-matched 3D cephalometric normative values. Patient-reported outcome measure tools regarding postoperative overall appearance and satisfaction with facial areas (ranging from 0 to 100 and 0 to 10, respectively) were administered. The number of needed or requested revisionary surgery was collected. RESULTS: No difference (all p > 0.05) was observed between the orthognathic-surgery-treated patients and the normative value for most of the tested 3D cephalometric parameters, with the exception (p < 0.05) of three mandible and occlusal-plane-related parameters. Both patient-reported outcome measure tools showed that patients' satisfaction with their postoperative appearance was high for overall face (89.7 ± 4.5) and specific facial regions (nose, 7.1 ± 1.3; lip, 8.3 ± 1.6; upper gum, 8.5 ± 1.2; cheek, 8.8 ± 1.1; chin, 9.2 ± 1.2; and teeth, 9.3 ± 0.8), with no need for revisionary surgery. CONCLUSION: The patients treated with a full 3D digital planning-assisted two-jaw surgery had a similar 3D dental relation, facial convexity, and symmetry compared to healthy ethnicity-matched individuals, and they reported higher satisfaction levels with their postoperative facial appearance results.

A novel CAD/CAM composite occlusal splint for intraoperative verification in single-splint two-jaw orthognathic surgery.

BACKGROUND: Previous computer-generated splints were designed and produced without modification than the traditional occlusal splints, which did not facilitate surgeon's intraoperative judgment in the single-splint two-jaw orthognathic surgery. Modifications of the digital occlusal splint can be achieved using computer-aided design and computer-aided manufacturing (CAD/CAM) software. This study reported the design, clinical application and validation of a novel CAD/CAM occlusal splint. METHODS: The maxillary and mandibular segments were fixed into the final occlusal splint and moved to the planned position according to the 3-dimensional simulation. The composite occlusal splint has 4 orthogonal bars to facilitate intraoperative assessment of the dental and skeletal midline, facial soft tissue midline, occlusal plane, upper tooth show, facial symmetry and facial bone position. To validate the surgical outcome, 5 parameters including pitch, roll and yaw rotations, midline deviation and chin position were measured on the virtual plan and the postoperative cone-beam computed tomography images to quantify the difference. RESULTS: The results showed no significant differences in the 5 parameters between the simulation and postoperative images. The root-mean-square difference between the conventional splints and CAD/CAM surgical splint ranged from 0.18 to 0.31 mm by superimposition of the two image models. All patients were satisfied with the treatment outcomes. Overall, this novel occlusal splint is ideal for verification of the maxillomandibular position during surgery. CONCLUSION: The novel composite occlusal splint provided useful and informative check to verify the maxillomandibular complex (MMC) position and facial appearance in single-splint two-jaw orthognathic surgery.

Cheek soft tissue prediction in cleft orthognathic surgery: A 3D computer-assisted investigation with comparative analysis.

BACKGROUND: The Le Fort I maxillary advancement and rotational movement have been adopted to treat patients with cleft-related skeletal Class III pattern and anteromedial cheek soft tissue deficiency, but cleft-specific cheek soft tissue prediction data are insufficient. This 3D imaging-based study addressed the issue. METHODS: 3D craniofacial soft tissue and bone models were created from 32 consecutive patients who received computer-aided two-jaw orthognathic surgery for the correction of cleft-related Class III deformity and cheek soft tissue deficiency. Using superimposed 3D models, the cheek volumetric change, the cheek sagittal movement, and the 3D cheek mass position were calculated. 3D data from orthognathic surgery-treated patients with no cleft (noncleft cohort) and individuals with no facial deformity (3D norm value) were retrieved for comparative analysis. RESULTS: Surgical maxillary advancement (p < 0.001) but not maxillary clockwise rotation (p > 0.05) had a significant impact on the cheek soft tissue change, with prediction models showing that maxillary advancement elucidated 77 and 79% of this change on the cleft and noncleft sides, respectively. Cleft cohort (0.46±0.12) had a significantly (p < 0.001) smaller cheek soft-to-hard tissue ratio than that of the noncleft cohort (0.73±0.13). Cleft maxillary advancements >4 mm resulted in a 3D cheek mass position (2.1±1.1 mm) similar (p > 0.05) to the 3D norm value (2.2±1.2 mm), but different (p = 0.037) from the noncleft cohort (2.38±0.7 mm). CONCLUSION: This study showed that maxillary advancement but not the maxillary rotation affects the cheek soft tissue change, and the predictive values and comparative data could assist the orthodontist-surgeon interaction during preoperative planning and patient counseling.

Maintaining the space between the mandibular ramus segments during bilateral sagittal split osteotomy does not influence the stability.

BACKGROUND/PURPOSE: Three-dimensional computer-assisted orthognathic surgery allows to simulate the space between the mandibular ramus segments, i.e. intersegmental gap, for the correction of facial asymmetry. The purposes of the study were to estimate the screws- and mandible bone-related changes from the early postoperative period to the period after the debonding and to measure the association between the intersegmental gap volume and the screws- and mandible bone-related changes. METHODS: This cone-beam computed tomography (CBCT)-assisted retrospective study assessed the stability of the bicortical positional screw fixations in maintaining the space between the mandibular ramus segments after bilateral sagittal split osteotomy in correction of 31 patients with malocclusion and facial asymmetry. The primary predictor variable was the CBCT-based intersegmental gap volume at early postoperative period (T1). The primary outcome variables were CBCT-based screws- and bone-related measurement changes between the T1 and T2 (at debonding) periods. RESULTS: No significant differences were observed in screws-related linear and angular measurements between T1 and T2 virtual models. Some of mandible bone-related linear and angular measurements had significant differences (P < 0.05) between the T1 and T2 images, but with no clinical repercussion such as need of revisionary surgery. The gap volume and the screws- and bone-related changes had no significant correlations. CONCLUSION: This study contributes to the multidisciplinary-related literature by demonstrating that the bicortical positional screws-based fixation technique in maintaining the three-dimensional-simulated space between the mandibular ramus segments is a stable and clinically acceptable option for correction of facial asymmetry associated with malocclusion, regardless of intersegmental gap size.

Automatic Assessment of 3-Dimensional Facial Soft Tissue Symmetry Before and After Orthognathic Surgery Using a Machine Learning Model: A Preliminary Experience.

PURPOSE: An objective and quantitative assessment of facial symmetry is essential for the surgical planning and evaluation of treatment outcomes in orthognathic surgery (OGS). This study applied the transfer learning model with a convolutional neural network based on 3-dimensional (3D) contour line features to evaluate the facial symmetry before and after OGS. METHODS: A total of 158 patients were recruited in a retrospective cohort study for the assessment and comparison of facial symmetry before and after OGS from January 2018 to March 2020. Three-dimensional facial photographs were captured by the 3dMD face system in a natural head position, with eyes looking forward, relaxed facial muscles, and habitual dental occlusion before and at least 6 months after surgery. Three-dimensional contour images were extracted from 3D facial images for the subsequent Web-based automatic assessment of facial symmetry by using the transfer learning with a convolutional neural network model. RESULTS: The mean score of postoperative facial symmetry showed significant improvements from 2.74 to 3.52, and the improvement degree of facial symmetry (in percentage) after surgery was 21% using the constructed machine learning model. A Web-based system provided a user-friendly interface and quick assessment results for clinicians and was an effective doctor-patient communication tool. CONCLUSIONS: This work was the first attempt to automatically assess the facial symmetry before and after surgery in an objective and quantitative value by using a machine learning model based on the 3D contour feature map.

On construction of transfer learning for facial symmetry assessment before and after orthognathic surgery.

Orthognathic surgery (OGS) is frequently used to correct facial deformities associated with skeletal malocclusion and facial asymmetry. An accurate evaluation of facial symmetry is a critical for precise surgical planning and the execution of OGS. However, no facial symmetry scoring standard is available. Typically, orthodontists or physicians simply judge facial symmetry. Therefore, maintaining accuracy is difficult. We propose a convolutional neural network with a transfer learning approach for facial symmetry assessment based on 3-dimensional (3D) features to assist physicians in enhancing medical treatments. We trained a new model to score facial symmetry using transfer learning. Cone-beam computed tomography scans in 3D were transformed into contour maps that preserved 3D characteristics. We used various data preprocessing and amplification methods to determine the optimal results. The original data were enlarged by 100 times. We compared the quality of the four models in our experiment, and the neural network architecture was used in the analysis to import the pretraining model. We also increased the number of layers, and the classification layer was fully connected. We input random deformation data during training and dropout to prevent the model from overfitting. In our experimental results, the Xception model and the constant data amplification approach achieved an accuracy rate of 90%.

Three-Dimensional Computer-Assisted Orthognathic Surgery: Traditional Hybrid Versus Full Digital Planning Models.

PURPOSE: Three-dimensional (3D) computer-aided planning has truly revolutionized orthognathic surgery (OGS) treatment, but no study has compared the traditional hybrid and full 3D digital planning models. This study compared these virtual planning models in the treatment of asymmetric maxillomandibular disharmony. METHODS: Young adult patients with an asymmetric skeletal class III deformity who underwent 3D computer-aided 2-jaw OGS using hybrid (alginate dental impression, 2D cephalometric tracings, manual-guided stone model surgery, occlusion setup, and splint fabrication; n = 30) or full digital (laser-scanned dentition, 3D cephalometric tracings, virtual-based occlusion setup and surgery, and computer-generated surgical splint; n = 30) planning models were consecutively recruited. Preoperative and postoperative 3D cephalometric analyses (dental relation, skeletal assessments based on sagittal and frontal views, and soft tissue evaluations) were adopted for intragroup and intergroup comparisons. Postoperative patient-perceived satisfaction with facial appearance was also recorded. RESULTS: Both hybrid and full digital planning groups had significant (all P < 0.05) improvements after surgery with respect to facial convexity, incisor overjet, and frontal symmetry parameters. The full 3D digital planning-based OGS treatment had similar (all P > 0.05) 3D cephalometric-derived outcomes (preoperative, postoperative, and treatment-induced change data) and patient-perceived outcomes compared with the traditional hybrid 3D planning method. CONCLUSIONS: For the decision-making process in selecting the planning model, multidisciplinary teams could consider additional parameters such as patient comfort, storage needs, convenience for data reuse, overall planning time, availability, and costs.

Avoiding Inferior Alveolar Nerve Injury during Osseous Genioplasty: A Guide for the Safe Zone by Three-Dimensional Virtual Imaging.

BACKGROUND: No consensus exists about the safest position for performing the osseous genioplasty, with 5 to 6 mm below the mental foramen being the most frequently recommended position. This study intends to generate a safe distance guide to minimize the risk of inferior alveolar nerve injury during osteotomy. METHODS: Pretreatment cone-beam computed tomography-derived three-dimensional models from adult patients with skeletal class I to III patterns and cleft lip/palate deformity who underwent orthodontic-surgical interventions (n = 317) were analyzed. A three-dimensional vertical distance between the inferior margin of the mental foramen and the lowest point of the inferior alveolar nerve canal was measured in each three-dimensional hemimandible (n = 634). Statistical analysis was performed to generate the safe distance guide in a stepwise fashion at 95, 99, and 99.99 percent confidence levels. RESULTS: Class III (4.35 ± 1.42 mm) and cleft lip/palate (4.42 ± 1.53 mm) groups presented significantly (p < 0.001) larger three-dimensional distances than class I (3.44 ± 1.54 mm) and class II (3.66 ± 1.51 mm) groups. By considering the 5- to 6-mm safe distance parameter, 6.4, 5.0, 10.6, 16, and 9.9 percent of hemimandibles were at risk of osteotomy-induced nerve injury in the class I, class II, class III, cleft lip/palate, and overall cohorts, respectively. Overall, the safe distance zone to perform the osteotomy was set at 7.06, 8.01, and 9.12 mm below the mental foramen, with risk probabilities of 2.5, 0.5, and 0.0005 percent, respectively. CONCLUSION: This study contributes to patient safety and surgeon practice by proving a safe distance guide for genioplasty.

Patient- and 3D morphometry-based nose outcomes after skeletofacial reconstruction.

Patient satisfaction with the shape and appearance of their nose after orthognathic surgery-based skeletofacial reconstruction is an important, but often overlooked, outcome. We assessed the nose-related outcomes through a recently developed patient-reported outcome instrument and a widely adopted 3D computer-based objective outcome instrument, to verify any correlation in the results produced by these tools. We collected FACE-Q nose appearance reports (2 scales) and 3D nasal morphometry (10 parameters) from patients with class III skeletal pattern and congenital cleft lip palate deformity (n = 23) or developmental dentofacial deformity (n = 23) after (>12 months) skeletofacial reconstruction. The cleft and dentofacial cohorts demonstrated significantly (p < 0.001) poorer satisfaction scores with regard to the FACE-Q nostrils scale than the normal age-, gender-, and ethnicity-matched subjects (n = 107), without any significant difference in FACE-Q nose scale. The cleft cohort had significantly (p < 0.001) smaller nasal length, nasal tip projection, and columellar angle and greater nasal protrusion, alar width, and columellar-labial angle values than the dentofacial and normal cohorts; however, there were no significant differences between the dentofacial versus normal cohorts. The FACE-Q nose and nostrils scales were significantly (p < 0.001; r = -0.26-0.27) correlated to the results of the 3D morphometric analysis, with regard to nasal length, alar width, columella angle, and columellar-labial angle parameters. This study revealed differences in satisfaction with the appearance of the nose according to the type of underlying deformity, and demonstrated a significant correlation (low correlation coefficients) between the patient-reports and 3D image-based outcome measure tools, which has implications for multidisciplinary-centered research, auditing, and clinical care.