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.

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.

Skeletofacial Reconstruction for Cleft-Related Deformities: Four Decades of Evolving Cleft Care.

Skeletofacial reconstruction in skeletally mature patients with cleft lip/palate can be challenging because of multifaceted condition-specific anatomical features in addition to several repercussions from surgical intervention during the growing period. This surgical report presents the history and evolving philosophy of cleft-skeletofacial reconstruction at the Chang Gung Craniofacial Center, a referral center for cleft care in Taiwan. The maximization of satisfactory function and the appearance outcome-burden ratio have been the fundamental aims for this team to develop and upgrade cleft-skeletofacial reconstruction over the past 4 decades, with more than 10,000 mature patients treated. The study highlights key lessons learned in outcome-based and patient-oriented changes over time until the current approach, which focuses on patient-centered care with a comprehensive, multidisciplinary, and team-based model. Substantial advances in surgical, orthodontic, anesthetic, and computer imaging aspects have contributed to improving and optimizing the correction of a broad spectrum of facial and occlusal deformities while ensuring safety, predictability, efficiency, and stability in outcomes. Understanding the development and refinement of cleft-skeletofacial reconstruction over the time and transferring these time-tested and scientifically validated protocols and principles to clinical practice may serve as a reliable foundation to continue the advancement and enhancement of the delivery of surgical cleft care worldwide.

Velopharyngeal function change after two-jaw orthognathic surgery in patients with cleft: A study on 162 consecutive cases.

BACKGROUND: Orthognathic surgery (OGS) is a common intervention used to correct midfacial hypoplasia in patients with cleft. Previous studies have reported that LeFort I maxillary advancement may impact velopharyngeal function, but similar investigations focusing on two-jaw OGS have not been conducted. METHODS: A total of 162 consecutive patients with cleft lip and palate who underwent two-jaw OGS between 2015 and 2020 were enrolled. Clinical data were collected, and preoperative and postoperative skeletal measurements were obtained from cephalometric images. Velopharyngeal function was evaluated using perceptual analysis and nasopharyngoscopy. A logistic regression model was employed for the risk factors associated with changes in velopharyngeal function. RESULTS: After two-jaw OGS, 82.1% of patients showed no change in velopharyngeal function, while 3.7% experienced improvement and 14.2% exhibited worsening of function. In addition, the changes in velopharyngeal function were statistically significant comparing to the pre-OGS velopharyngeal status. A multivariable logistic regression revealed that the amount of maxillary advancement independently predicted the deterioration of post-OGS velopharyngeal function (odds ratio = 1.74, 95% confidence interval (CI) = 1.20-2.52, p = 0.004). The receiver operating characteristic curve based on maxillary advancement demonstrated good discrimination, with an area under the curve of 0.727 (95% CI = 0.62-0.83, p = 0.001). The Youden index was 4.27 mm. CONCLUSION: Despite the risk of velopharyngeal function deterioration in patients with cleft palate undergoing OGS, some individuals have experienced improved function following two-jaw OGS. The extent of maxillary advancement has a negative impact on the velopharyngeal function.

Long-term treatment outcome of patients with complete bilateral cleft lip and palate: a retrospective cohort study.

BACKGROUND: Patients with cleft lip and palate have functional and esthetic impairment and typically require multiple interventions in their life. Long-term evaluation following a treatment protocol, especially for patients with complete bilateral cleft lip and palate (BCLP), is important but was rarely reported in the literature. PATIENTS AND METHODS: A retrospective review was conducted on all patients with complete BCLP born between 1995 and 2002 and treated at our center. Inclusion criteria were having adequate medical records and receiving continuous multidisciplinary team care at least until 20 years of age. Exclusion criteria were lack of regular follow-up and congenital syndromic abnormalities. The medical records and photos were reviewed, and facial bone development was evaluated using cephalometric analysis. RESULTS: A total of 122 patients were included, with a mean age of 22.1 years at the final evaluation in this study. Primary one-stage cheiloplasty was performed in 91.0% of the patients, and 9.0% underwent two-stage repair with an initial adhesion cheiloplasty. All patients underwent two-flap palatoplasty at an average of 12.3 months. Surgical intervention for velopharyngeal insufficiency was required in 59.0% of patients. Revisional lip/nose surgery was performed in 31.1% during growing age and in 64.8% after skeletal maturity. Orthognathic surgery was applied in 60.7% of patients with retruded midface, of which 97.3% underwent two-jaw surgery. The average number of operations to complete the treatment was 5.9 per patient. CONCLUSION: Patients with complete BCLP remain the most challenging group to treat among the cleft. This review revealed certain suboptimal results, and modifications have been made to the treatment protocol. Longitudinal follow-up and periodic assessment help to establish an ideal therapeutic strategy and improve overall cleft care.

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.

Outcome of facial contour asymmetry after conventional two-dimensional versus computer-assisted three-dimensional planning in cleft orthognathic surgery.

Computer-assisted 3D planning has overcome the limitations of conventional 2D planning-guided orthognathic surgery (OGS), but difference for facial contour asymmetry outcome has not been verified to date. This comparative study assessed the facial contour asymmetry outcome of consecutive patients with unilateral cleft lip and palate who underwent 2D planning (n = 37)- or 3D simulation (n = 38)-guided OGS treatment for correction of maxillary hypoplasia and skeletal Class III malocclusion between 2010 and 2018. Normal age-, gender-, and ethnicity-matched individuals (n = 60) were enrolled for comparative analyses. 2D (n = 60, with 30 images for each group) and 3D (n = 43, with 18 and 25 images for 2D planning and 3D simulation groups, respectively) photogrammetric-based facial contour asymmetry-related measurements were collected from patients and normal individuals. The facial asymmetry was further verified by using subjective perception of a panel composed of 6 blinded raters. On average, the facial contour asymmetry was significantly (all p < 0.05) reduced after 3D virtual surgery planning for all tested parameters, with no significant differences between post-OGS 3D simulation-related values and normal individuals. No significant differences were observed for pre- and post-OGS values in conventional 2D planning-based treatment, with significant (all p < 0.05) differences for all normal individuals-related comparisons. This study suggests that 3D planning presents superior facial contour asymmetry outcome than 2D planning.

Outcome of Patients with Complete Unilateral Cleft Lip and Palate: 20-Year Follow-Up of a Treatment Protocol.

BACKGROUND: The treatment plan for cleft lip and palate varies among centers and requires long-term evaluation of its final outcome. METHODS: A consecutive series of patients born from 1994 to 1996 were reviewed. Inclusion criteria were complete unilateral cleft lip and palate, undergoing all treatment procedures performed by the team, and continuous follow-ups until 20 years of age. Exclusion criteria were incomplete data, having microform cleft lip on the contralateral side, presence of the Simonart band, and other abnormalities. RESULTS: A total of 72 patients were included. Average age at final evaluation was 21.3 years; 83.3 percent of patients underwent one-stage rotation-advancement lip repair and 16.7 percent underwent two-stage repair with an initial adhesion cheiloplasty. All patients underwent palate repair using the two-flap method at an average age of 12.3 months. Velopharyngeal insufficiency occurred and required surgical interventions in 19.4 percent during the preschool age and in 16.7 percent at the time of alveolar bone grafting; 56.9 percent of patients underwent secondary lip/nose revision during the growing age. Regular orthodontic treatment was administered to 34.7 percent of patients between 12 and 16 years of age. Orthodontic treatment and orthognathic surgery were applied in 37.5 percent of the patients after maturity. The average number of surgical procedures to complete the treatment was 4.8 per patient. CONCLUSIONS: This treatment protocol provided generally acceptable final outcome after the 20-year follow-up. Some results were less ideal and have resulted in modifications of the planning and methods in the protocol. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Do miniscrews remain stationary under orthodontic forces?

Miniscrews have been used in recent years for anchorage in orthodontic treatment. However, it is not clear whether the miniscrews are absolutely stationary or move when force is applied. Sixteen adult patients with miniscrews (diameter = 2 mm, length = 17 mm) as the maxillary anchorage were included in this study. Miniscrews were inserted on the maxillary zygomatic buttress as a direct anchorage for en masse anterior retraction. Nickel-titanium closed-coil springs were placed for the retraction 2 weeks after insertion of the miniscrews. Cephalometric radiographs were taken immediately before force application (T1) and 9 months later (T2). The cephalometric tracings at T1 and T2 were superimposed for the overall best fit on the structures of the maxilla, cranial base, and cranial vault to determine any movement of the miniscrews. The miniscrews were also evaluated clinically for their mobility (0: no movement, 1: < or =0.5 mm, 2: 0.5-1.0 mm, 3: >1.0 mm). The mobility of all miniscrews was 0 at T1 and T2. On average, the miniscrews tipped forward significantly, by 0.4 mm at the screw head. The miniscrews were extruded and tipped forward (-1.0 to 1.5 mm) in 7 of the 16 patients. Miniscrews are a stable anchorage but do not remain absolutely stationary throughout orthodontic loading. They might move according to the orthodontic loading in some patients. To prevent miniscrews hitting any vital organs because of displacement, it is recommended that they be placed in a non-tooth-bearing area that has no foramen, major nerves, or blood vessel pathways, or in a tooth-bearing area allowing 2 mm of safety clearance between the miniscrew and dental root.