History and Evolution of Orthognathic Surgery at Chang Gung Craniofacial Center

Appraising mandibular prognathism in class III malocclusion following orthognathic surgery: Patient-reported and cephalometry-based outcomes

Patients with class III malocclusion often exhibit mandibular prognathism and complain of "prognathic appearance". The overall positive effects of orthognathic surgery on facial appearance have been demonstrated using patient-reported outcome measures (PROMs), but studies investigating the correlation between subjective PROMs results and objective measurements of imaging studies are sparse in the literature. This study recruited consecutive patients with skeletal class III malocclusion who underwent two-jaw orthognathic surgery between January 2016 and January 2021. The PROMs survey was conducted focusing on subjective perception of mandibular appearance. Lateral cephalometric images were measured to examine the correlation with the PROMs results. A total of 96 patients were eligible for this study. Of these, 74 patients (77.1%) reported complete correction of prognathic appearance postoperatively, whereas 22 patients (22.9%) perceived residual prognathic appearance. In a comparison of postoperative measurements between completely and incompletely satisfied patients, there were significant differences in SNB, ANB, convexity, facial angle, Nv-B, Nv-Pog, SN'B', soft tissue facial angle, lip-chin-throat angle, N'v-B', and N'v-Pog'. The PROM results were significantly associated with the objective measurements of imaging studies. Investigating the correlation between PROMs and objective measurements enables integration of patients' perception of the outcomes into future therapeutic strategy and surgical planning, contributing to the enhancement of patient satisfaction.

Comparative Assessment of Orthodontic and Aesthetic Outcomes after Orthognathic Surgery with Clear Aligner or Fixed Appliance Therapy

BACKGROUND

Clear aligner therapy has an aesthetic advantage over fixed appliance therapy. However, to our knowledge, no study has objectively compared patient orthodontic and aesthetic outcomes between clear aligner and fixed appliance therapies administered after orthognathic surgery (OGS).

METHODS

This study included patients with no history of congenital craniofacial deformities who underwent surgery-first OGS and received clear aligner or fixed appliance therapy. The patients' grades on the Dental Health Component (DHC) and Aesthetic Component of the Index of Orthodontic Treatment Need and scores on the Peer Assessment Rating (PAR) index were calculated before OGS (T0), after OGS (T1), and after orthodontic therapy (T2).

RESULTS

This study included 33 patients (clear aligner therapy, n = 19; fixed appliance therapy, n = 14). No considerable between-group differences were noted in the DHC and AC grades at T0, T1, or T2. Furthermore, percentage of reduction in the PAR index score was more significant in the clear aligner group (74.4%) than in the fixed appliance group (63.2%) from T0 to T1 ( P = 0.035); however, no between-group differences were noted from T1 to T2 or from T0 to T2. Both groups exhibited substantially improved DHC grades, Aesthetic Component grades, and PAR index scores at T1 and T2.

CONCLUSIONS

Patient outcomes were similar between the clear aligner and fixed appliance groups after orthodontic therapy. However, the former group exhibited more favorable immediate results after OGS than did the latter group. Thus, as an adjunct therapy for patients with malocclusion, clear aligner therapy may be more effective than fixed appliance therapy.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Three-Dimensional Comparative Changes in the Pharyngeal Airway of Patients with Cleft after Two-Jaw Orthognathic Surgery

BACKGROUND

The present study evaluated the three-dimensional changes of the pharyngeal airway after orthognathic surgery (OGS) in patients with unilateral and bilateral clefts, and in unilateral cleft patients with and without pharyngeal flap (PF).

METHODS

Forty-five patients with unilateral or bilateral clefts undergoing OGS were enrolled. Cone-beam computed tomographic images were obtained before and after OGS. We measured the pharyngeal airway volumes, minimal cross-sectional area, and the horizontal displacement of facial landmarks.

RESULTS

The patients with bilateral cleft exhibited smaller initial velopharyngeal volume (unilateral, 8623 mm 3 ; bilateral, 7781 mm 3 ; P = 0.211), whereas the velopharyngeal volume increased significantly with a median of 744 mm 3 after OGS ( P = 0.031). The median horizontal displacement of A point was 2.9 and 2.6 mm among the patients with unilateral and bilateral clefts, respectively ( P = 0.276), and the median horizontal displacement of B point was -2.9 and -3.3 mm among patients with unilateral and bilateral clefts, respectively ( P = 0.618). The unilateral cleft patients with PF exhibited lower initial velopharyngeal volume (patients with a history of PF surgery, 7582 mm 3 ; patients without a history of PF surgery, 8756 mm 3 ; P = 0.129) and a lower increase in velopharyngeal volume (patients with a history of PF surgery, 437 mm 3 ; patients without a history of PF surgery, 627 mm 3 ; P = 0.739) after OGS.

CONCLUSIONS

Midface hypoplasia and the decrease in the velopharyngeal volume were more prominent among the bilateral cleft patients and the unilateral cleft patients with PF. After OGS, the velopharyngeal volume increased considerably among the bilateral cleft patients, but no considerable differences were noted among the unilateral cleft patients with PF.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Comparison between one-jaw and two-jaw designs in virtual surgery planning for patients with class III malocclusion

Orthognathic surgery is highly effective for treating maxillomandibular discrepancies in patients with class III malocclusion. However, whether one- or two-jaw surgery should be selected remains controversial. Our study aimed to evaluate quantitative differences between one-jaw and two-jaw surgical designs. In total, 100 consecutive patients with skeletal class III malocclusion who underwent orthognathic surgery with preoperative three-dimensional simulation between August 2016 and November 2021 were recruited. Based on the same final occlusal setup, a two-jaw surgery design and two types of one-jaw design were created. In total, 400 image sets, including preoperative images and three types of surgical simulation, were measured and compared. The one-jaw mandibular setback design led to improvement in most cephalometric measurements and facial symmetry. Although the one-jaw maxillary advancement design improved the ANB angle and facial convexity, it induced maxillary protrusion and reduced facial symmetry. Compared with the other designs, the two-jaw design provided significantly closer cephalometric measurements to the normative values, better symmetry, and less occlusal cant. Overall, the two-jaw design provided a quantitatively better facial appearance in terms of symmetry, proportion, and profile. Although an optimal surgical design necessitates thorough preoperative evaluation and a shared decision-making process, two-jaw surgery can be considered for improving overall facial esthetics and harmony.

Chang Gung Forum: An Exemplary Strategy for Implementing a Multidisciplinary Network of Experts in Craniofacial Anomalies

INTRODUCTION

The Chang Gung Forum has been dedicated to the care of craniofacial anomalies since 2000. This annual continuing medical education program focuses on orofacial cleft and surgery-first orthognathic surgery by providing up-to-date information and management guidelines. This study explored how the Chang Gung Forum has influenced medical perspectives, decisions, and practices in a multidisciplinary craniofacial team.

METHODS

Between 2000 and 2022, 20 Chang Gung Forums have been held. A questionnaire was distributed among 170 attendees who had participated in the forum more than once. The questionnaire collected information on the participants' experiences and levels of satisfaction with the educational program and whether or how it had influenced their clinical practice.

RESULTS

Valid responses from 86 attendees (response rate, 50.6%) who had participated more than once were collected and analyzed. The overall satisfaction rate of the Chang Gung Forum based on the respondents' most recent visits was 4.28 ± 0.63 out of 5. Of the respondents, 90.9% acknowledged changes in their clinical practice, with modifications in surgery plans and decisions being the most notable (48.5%). In addition, comprehension increased throughout years of attending the annual forum (P < 0.001).

CONCLUSION

The Chang Gung Forum has contributed markedly to the community of congenital craniofacial anomalies. The program will continue providing updated information and influencing the clinical decision-making of health care professionals.

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.

One-splint versus two-splint technique in orthognathic surgery for class III asymmetry: comparison of patient-centred outcomes

OBJECTIVES

Two-jaw orthognathic surgery (OGS) is done using either the one-splint technique with free-hand positioning of the maxillomandibular complex or the two-splint technique with intermediate splints to position the maxilla. It is uncertain which technique achieves better outcomes. This study compares frontal soft tissue symmetry and subjective patient QoL between one-splint and two-splint techniques in skeletal Class III asymmetry patients undergoing OGS with three-dimensional surgical planning.

MATERIALS AND METHODS

This retrospective case-control study comprised 34 one-splint and 46 two-splint OGS patients. Frontal photographs and Orthognathic Quality of Life Questionnaire (OQLQ) were done pre- and post-treatment. Frontal soft tissue symmetry was analysed with the anthropometric Facial Symmetry Index. Measurements were compared with t-tests and chi-squared tests with p-value set at 0.05.

RESULTS

The groups differed in pre-treatment ANB and OQLQ scores. The two-splint group showed significant improvement in all symmetry measures. The one-splint group showed significant improvement in all symmetry measures except midface deviation, upper contour deviation and the Facial Contour Symmetry Index. Both groups showed significant improvement in OQLQ scores. There were no significant differences in post-treatment symmetry measurements and OQLQ scores between groups.

CONCLUSIONS

Although two-splint technique may better improve contour symmetry, there were no significant differences in frontal soft tissue symmetry and QoL after OGS in skeletal Class III asymmetry with either one-splint or two-splint technique, with both techniques resulting in significant improvement.

CLINICAL RELEVANCE

One-splint and two-splint surgical techniques produce similar patient-centred outcomes in Class III asymmetry patients.

Sleep, Distressed Appearance, and Quality of Life Relate to Satisfaction with Orthognathic Surgery

BACKGROUND

In this study, we aimed to identify factors correlating with satisfaction with orthognathic surgery in order to improve its outcome.

METHODS

We recruited 77 participants who had received orthognathic surgery and 32 age- and gender-matched normal-controls. Questionnaires that included devised questions for family support, Big Five Inventory, Derriford Appearance Score, Pittsburgh Sleep Quality Index, Hospital Anxiety and Depression Scale, 36-Item Short-Form Health Survey, and a visual analogy scale for satisfaction, were completed before and one month and nine months after the surgery. The statistical analysis methods included descriptive statistics, t-test, and Pearson correlation.

RESULTS

All participants received the preoperative and one-month follow-up, while 28 also completed the nine-month follow-up. Satisfaction was not significantly related to demographic data, but long-term satisfaction was related to an extraverted personality. The preoperative and postoperative results of the Derriford Appearance Scale were related to short-term and long-term satisfaction. Furthermore, both the preoperative and one-month postoperative Pittsburgh Sleep Quality Index findings were significantly related to short-term satisfaction. The postoperative 36-Item Short-Form Health Survey was significantly related to short-term and long-term satisfaction.

CONCLUSIONS

Not only subjective distress and dysfunction of appearance but also sleep problems and quality of life were correlated to satisfaction with orthognathic surgery. In the future, relevant interventions can be developed to further improve patient's satisfaction and their physical and mental health.

One-Year Craniofacial Surgery Fellowship at Chang Gung Memorial Hospital

ABSTRACT

Residency trainings in oral and maxillofacial surgery, plastic surgery, or otolaryngology do not sufficiently cover all aspects of craniofacial surgery to enable fresh graduates to independently practice as craniofacial surgeons. Fellowship trainings are almost mandatory to gain added skills and knowledge in the subspecialty. There are limited number of fellowship centers around the globe that accept international fellows, provide an excellent hands-on experience, arrange free accommodation and pay stipend to the selected candidates. The author presents his critical review of 1-year craniofacial surgery fellowship at Chang Gung Memorial Hospital, Taiwan, sponsored by Noordhoff Craniofacial Foundation (NCF), during which he rotated in pediatric craniofacial surgery unit for five and half months, orthognathic surgery unit for 4 months and craniofacial trauma and reconstruction unit for two and half months. The surgical log is presented along with critical review of individual postings, pearls of the overall fellowship along with suggestions for interested candidates to join the fellowship.

The Effect of Absorbable and Non-Absorbable Sutures on Nasal Width Following Cinch Sutures in Orthognathic Surgery

Background: Non-absorbable materials (nylon) are always used in cinch sutures to maintain nasal width and to improve harmonious facial symmetry in orthognathic surgery. However, a few drawbacks of nylon materials have been clinically reported following orthognathic surgery, such as nasal irritation and exposure of the sutures. An absorbable material (PDS) has been proposed in cinch sutures, not only to avoid the complications of nylon but also to stabilize the nasal width for a long-term follow-up. Methods: Fifty-seven patients with Angle’s malocclusion classification III receiving orthognathic surgery were enrolled in this study. A non-absorbable material (nylon) and an absorbable material (PDS) were utilized for the cinch sutures. Pre-operative (T1) and post-operative six-month (T2) craniofacial 3D images were collected for all patients to measure the alar curvature (Ac) width and the alar base (Al) width. A significance level of p < 0.05 was applied in the statistical analysis. Results: With the approval of IRB, cinch suturing was performed with nylon in 29 patients and with PDS in 28 patients. Pre-operative Ac and Al distances showed no significant difference between these two groups. There were also no significant differences between the suture materials in the peri-operative change in nasal width, including Ac (nylon: 1.999 ± 1.40; PDS: 1.484 ± 0.97; p = 0.112) and Al (nylon: 1.861 ± 1.66; PDS: 1.115 ± 0.92; p = 0.056). Conclusions: For cinch sutures in orthognathic surgery, PDS can maintain the peri-operative nasal width similarly to nylon; additionally, it can be absorbed in a timely manner without the drawbacks of non-absorbable materials.

Short-term and Long-term Psychological Impact and Quality of Life of Patients Undergoing Orthognathic Surgery

Background

Orthognathic Surgery (OGS) is a surgery for patients with dento-facial deformity but not all patients are satisfied with its outcome. The purpose of this study is to find out the short-term and long-term psychological impact and quality-of-life of OGS.

Methods

77 participants receiving OGS and 32 age and gender-matched controls were enrolled. The data of questionnaires were collected before OGS, one month and 9 months after OGS, including short form of the Derriford-Appearance-Scale (DAS-24), Big-Five-Inventory (BFI), Hospital-Anxiety-and-Depression-Scale (HADS), Pittsburgh-sleep-quality-index (PSQI), and 36-Item Short-Form-Health-Survey (SF-36). Variables were presented as mean ± standard deviation or frequency. Paired t-test, ANOVA and MANOVA were used to evaluate the pre-and post-surgery data.

Results

Short-term and long-term satisfaction of OGS was high. Before OGS, BFI showed the extraversion had significant difference between the male and female OGS subgroups. Several domains of DAS-24 were significantly different between the OGS and the control groups. Both groups had no significant difference in PSQI, HADS and SF-36, except sleep-efficiency. After OGS, many domains of DAS-24 were significantly improved and the improvement persisted to 9 months later. Sleep-latency, physical-function, role-limitations-due-to-physical-health and social-functioning exacerbated after OGS. Sleep-latency, physical-function, and social-functioning were improved 9 months after OGS, but sleep-efficiency and role-limitations-due-to-physical-health were still significantly worse than controls.

Conclusion

People received OGS for unfavorable appearance and the surgery could decrease their distress of appearance and impact to their daily living. Through long-term assessment, we should pay attention to sleep problems and role-limitations-due-to-physical-health after OGS.

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.

Type of maxillary segment mobilization affects three-dimensional nasal morphology

BACKGROUND

Surgical mobilization of the maxillary segment affects nasal morphology. This study assessed the impact of the type of maxillary mobilization on the three-dimensional (3D) nasal morphometry.

METHODS

Pre- and postsurgery cone beam computed tomography-derived facial image datasets of consecutive patients who underwent two-jaw orthognathic surgery were reviewed. Using preoperative 3D facial models as the positional reference of the skeletal framework, 12-month postoperative 3D facial models were classified into four types of maxillary mobilizations (advancement [n = 83], setback [n = 24], intrusion [n = 55], and extrusion [n = 52]) and four types of final maxillary positions (anterosuperior [n = 44], anteroinferior [n = 39], posterosuperior [n = 11], and posteroinferior [n = 13]). Six 3D soft tissue nasal morphometric parameters were measured, with excellent intra- and interexaminer reliability scores (ICC>0.897) for all the measurements. The 3D nasal change for each nasal parameter was computed as the difference between postoperative and preoperative measurement values.

RESULTS

The intrusion maxillary mobilization resulted in a significantly (all p<0.05) larger 3D nasal change in terms of alar width, alar base width, and nostril angle parameters, and a smaller change in terms of the nasal tip height parameter than the extrusion maxillary mobilization; however, no significant (all p>0.05) difference was observed between advancement and setback maxillary mobilizations. The anterosuperior and posterosuperior maxillary positions had a significantly (all p<0.05) larger 3D nasal change in terms of the alar base width and nostril angle than the anteroinferior and posteroinferior maxillary positions.

CONCLUSION

The type of maxillary mobilization affects the 3D nasal morphometry.

Three-Dimensional Computer-Assisted Single-Splint 2-Jaw Cleft Orthognathic Surgery: Toward Patient-Centered Surgical Rationale

Skeletally mature patients with cleft lip and palate commonly present with skeletofacial deformities characterized by varying degrees of intrinsic and acquired dentoskeletal and soft tissue abnormalities. These abnormalities are associated with scarring from previous surgeries and the asymmetric midline and facial contour that impose challenges for adequate reconstruction. These patients frequently require 2-jaw orthognathic surgery to improve occlusal function and for correction of facial deformities. In this article, we have detailed a 3-dimensional computer-assisted single-splint 2-jaw orthognathic surgery technique as a surgical approach for cleft skeletofacial reconstruction, allowing for the surgery to be tailored according to the specific needs and requests of the patients. Further, we have addressed the multidimensionality and specificities of cleft treatment, the wide versatility, adaptability, and applicability of this technique, and the patient-centered rationale for the adoption of this method.