Orthognathic Surgeon Research Articles

Changes in three-dimensional nasal morphology according to the direction of maxillary movement during Le Fort I osteotomy

Le Fort I (LFI) osteotomy is commonly performed by orthognathic surgeons; however, postoperative changes in nasolabial morphology are of concern. Several factors influence such changes, but it is difficult to accurately predict the postoperative results. This study evaluated the three-dimensional (3D) morphological changes in the nasal region according to the different directions of maxillary movement during LFI osteotomy. Forty-one patients who underwent LFI osteotomies were included. All patients were divided into maxilla-up (Group U: 20 patients) and maxilla-forward (Group F: 21 patients) groups. Soft tissue morphologies were determined preoperatively and 3 or 6 months postoperatively using an optical 3D scanner. All datasets were evaluated in terms of volume changes in nine subregions and changes in linear measurements around the nasal area. Both groups exhibited increased nasal volumes after surgery in the order of the three upper, three central, and three lower subregions. The change in volume of the central nasal region tended to be greater in Group U than that in Group F. We evaluated 3D morphological changes in the nasal region according to the direction of maxillary movement during LFI osteotomy. Group U exhibited a large change in the volume of the central nasal region.

Predicting the Future Focus of Orthognathic Surgery: Outcome-Driven Planning and Treatment With Function, Esthetics, and Occlusion as Key Indicators

As we reflect on the last 7decades since the first descriptions of modern orthognathic surgery (OGS) by Trauner and Obwegeser, we ponder what the next "game-changers" will be over the upcoming decades. We certainly recognize the prior contributions of Hullihen in 1849 and others in the 1920s and 1930s, and the pioneering work of Tessier, Obwegeser, and Bell in the 1960s and 1970s. Although there have been some changes in osteotomy design, as well as the landmark game-changing introduction of rigid internal fixation in the 1970s and 1980s, many of the more recent major changes have occurred only in the past decade or 2. The use of personalized and precision medicine with virtual surgical planning, and patient-specific implants has been transformational. Certainly, there will be more advances in the realm of diagnosis, surgical techniques and protocols, biomaterials and tissue engineering, and surgeon and patient education. But, as an international group of orthognathic surgeons, we believe that the most significant "next big thing" will be a clinical and research focus on patient-oriented outcomes and an improved quality of life. This will require outcome-driven planning and treatment with function, esthetics, and occlusion as key outcome indicators. Here we identify some shared visions and objectives for OGS with the aim to delineate future advancements to enhance the care of patients with dentofacial deformities. While we have organized the sections to cover key areas, the fundamental concepts include advances in these areas: diagnosis and treatment planning (eg, imaging, virtual surgical planning, artificial intelligence, and point-of-care workflows); materials development (eg, patient-specific implant, three-dimensional printing, tissue engineering, biodegradable implants, bone cements, titanium and magnesium implants, and developmental and regenerative medicine); and patient management (eg, minimally-invasive surgery, clear aligner therapy, temporary anchorage devices, outpatient OGS, age-centered treatment, and augmented reality/virtual reality).

A Practical Guide to Virtual Planning of Orthognathic Surgery and Splint Design Using Virtual Dentoskeletal Model

The present work is a manual that describes the practical aspects of optimizing dental precision by virtual dentoskeletal modeling, use the precises model in virtual planning, and splint design of orthognathic surgery. A single case study is used to demonstrate the stages involved in this approach, which include acquiring CBCT scan data and digital dental models, incorporating this data into developing a virtual dentoskeletal model using superimposition process to replace the unclear teeth. Utilizes virtual assessment and three-dimensional cephalometry to diagnose the maxillofacial deformity of the patient correctly. The results of the diagnosis played a crucial role in formulating a comprehensive plan for dental alignment, which involved osteotomy and correction of bone positions. The final step is to create a personalized splint. The importance of virtual tools is highlighted in our work to optimizing dental precision, diagnose and treat maxillofacial deformities. Present a virtual planning methodology for orthognathic surgeons as well as researchers.

Using a three-dimensional natural head position precise recording and transferring device to translate the natural head position into a 3-dimensional virtual patient: A dental technique

As computer-assisted surgical design becomes increasingly popular in maxillofacial surgery, the integration of the natural head position (NHP) of a 3-dimensional virtual patient has become a primary problem that orthognathic surgeons have to solve during virtual surgical planning. The present technique describes a way of transferring the horizon orientation of the NHP into a computer-aided design software program with a recently developed NHP recording and transferring device (Patent No. ZL202110992198.6 China). The device can record NHP using 5 marked points which can be visualized radiographically.

A retrospective study of orthognathic surgery reimbursement and volume changes at an American academic medical center over a 13-year period

This study aimed to measure the association between orthognathic surgeon reimbursement and surgical volume over time. A retrospective cohort study of patients who underwent orthognathic surgery from January 1, 2010, to December 23, 2022, at an academic medical center was performed. Five patients per year were randomly selected and evaluated for insurance type and associated costs to create representative averages. Pearson correlation analysis was performed to test associations over 13 years with 2-tailed significance reported and statistical significance set at P < .05. A total of 618 patients who underwent 942 procedures were included. The average procedure charge was $6,153.76, and the average total surgeon collection was $1,535.75 per procedure. When monetary values were adjusted to reflect 2010 purchasing power, there was a negative correlation between the average charge per procedure and the year (r[11] = -0.59, P = .04). The year was not significantly correlated with the average amount collected (r[11] = -0.09, P = .78) or average insurance reimbursement (r[11] = -0.52, P = .07). Collections by surgeons did not change significantly over 13 years and were not correlated with the volume of procedures performed. Increased collections were correlated with increased patient costs. The stagnation of surgeon collection is concerning in the face of increased monetary inflation during this period. Increased volume of surgeries per year was correlated with decreases in patient cost and total collections.

The accuracy and reliability of different midsagittal planes in the symmetry assessment using cone-beam computed tomography.

Symmetry is an essential component of esthetic assessment. Accurate assessment of facial symmetry is critical to the treatment plan of orthognathic surgery and orthodontic treatment. However, there is no internationally accepted midsagittal plane (MSP) for orthodontists and orthognathic surgeons. The purpose of this study was to explore a clinically friendly MSP, which is more accurate and reliable than what is commonly used in symmetry assessment. Forty patients with symmetric craniofacial structures were analyzed on cone-beam computed tomography (CBCT) scans. The CBCT data were exported to the Simplant Pro software to build four reference planes that were constructed by nasion (N), basion (Ba), sella (S), odontoid (Dent), or incisive foramen (IF). A total of 31 landmarks were located to determine which reference plane is the most optimal MSP by comparing the asymmetry index (AI). The mean value of AI showed a significant difference (p < 0.05) among four reference planes. Also, the mean value of AI for all landmarks showed that Plane 2 (consisting of N, Ba, and IF) and Plane 4 (consisting of N, IF, and Dent) were more accurate and stable. In conclusion, the MSP consisting of N, Dent, and IF shows more accuracy and reliability than the other planes. Further, it is more clinically friendly because of its significant advantage in landmarking.

Health Literacy Among Orthognathic Surgery Patients

The orthognathic surgery process requires a significant amount of information transfer between the orthognathic surgeon and the patient including information for navigating the surgeon-orthodontist collaboration, understanding the planned surgical procedures, and the perioperative process. The information transfer typically occurs over a 24-month treatment window through multiple appointments with face to face discussion and through patient education materials. Efficient and accurate transfer of information from the surgeon to the patient and their family allows for the patient to optimally navigate the process, participate in shared decision making and consent, and helps optimize patient outcomes.

Evaluation of the Predictability and Accuracy of Orthognathic Surgery in the Era of Virtual Surgical Planning

Virtual surgical planning allows orthognathic surgeons to design a surgical plan preoperatively and establish a personalized surgical protocol. This study aims to validate the predictability and accuracy of orthognathic surgery through a comparison of the three-dimensional (3D) models of the virtual planning and postoperative CBCT using free software (3D Slicer) on 40 patients who underwent bimaxillary orthognathic surgery. The distances of point A, point B, pogonion (Pog), and the first upper and lower molars, both in each axis (x, y, and z) and in the 3D space, were analyzed. The median of the distances in the mediolateral direction was the lowest, while the highest differences were found at point A and Pog in the anteroposterior direction (0.83 mm and 0.78 mm, respectively). Vertical differences were higher in the maxilla than in the mandible. In conclusion, we found that orthognathic bimaxillary surgery using virtual surgical planning was more accurate when positioning the bone segments in the mediolateral direction, using the information provided by the splint, as well as when positioning the mandible compared to the maxilla.

Clinical investigation of patients with jaw deformity with comorbidities

BackgroundWith improvements in the safety and stability of surgeries, the number of orthognathic surgeries is increasing. Most patients who undergo orthognathic surgeries are younger, and the number of orthognathic surgeries for patients with comorbidities is also increasing. We report a survey and clinical investigation of patients with comorbidities who underwent orthognathic surgeries at our department to improve the safety of orthognathic surgery.ResultsThe participants included 296 men and 712 women, with a mean age of 28 years (13–19 years, n=144; 20–29 years, n=483; 30–39 years, n=236; 40–49 years, n=102; 50–59 years, n=39; ≥60 years, n=4). In total, 347 patients underwent one-stage Le Fort type I osteotomy and sagittal split ramus osteotomy (SSRO), 243 underwent SSRO, 287 underwent plate removal, 126 underwent genioplasty and plate removal, and five underwent other surgeries. In total, 529 patients had comorbidities (52%), including allergic diseases (n=220, 33%), respiratory diseases (n=107, 16%), neurologic and psychiatric diseases (n=69, 10%), gynecologic diseases (n=28, 4%), hematologic diseases (n=27, 4%), cardiovascular diseases (n=24, 4%), digestive diseases (n=22, 3%), metabolic and endocrine diseases (n=18, 3%), spinal diseases (n=11, 2%), ophthalmologic diseases (n=11, 2%), renal and urological diseases (n=9, 1%), and other diseases (n=117, 18%). Among the patients with comorbidities, 11 with hemorrhagic diatheses (hemophilia and von Willebrand disease), arrhythmia (atrioventricular block), psychiatric disease (adjustment disorder), and metabolic disease (diabetes) required cautious perioperative management. The patient with hemophilia was managed with regular low-dose recombinant factor VIII replacement therapy, and the patient with type I diabetes mellitus was administered continuous insulin infusion and sliding-scale insulin therapy; both patients had an uneventful course.ConclusionsThe study findings suggest that with the increase in orthognathic surgeries, oral and maxillofacial surgeons should adequately manage cases requiring cautious perioperative control and highlight the importance of preoperative screening. Despite the well-established safety and postoperative stability of orthognathic surgeries, oral surgeons should adopt appropriate additional preventive measures for patients with comorbidities.

1264 A Cross-Sectional Study of Psychological Expectations of Orthognathic Surgery Patients Based on Their Typology

Abstract Aim Orthognathic surgery corrects craniofacial deformity which compromises breathing or masticatory function. Patients typology influences their expectations for physical and psychological transformation before and after surgery and is an emerging area of research. This study aims to evaluate: 1) subjective expectations and/or perceived outcomes and 2) whether orthognathic surgery meets patients’ expectations. Method A questionnaire-based cross-sectional survey was administered pre- and post-operatively. Patients were classified according to typology, namely metamorphosizers - patients with high expectation of psychological and physical changes, evolvers - opposite of metamorphosizers, pragmatists - low expectation of psychological and high expectation of physical changes, and shedders - opposite of pragmatists. A chi-square test was used to examine whether orthognathic surgery met patients’ expectations. Results A total of 27 patients consisting of 19 pre-operative and 8 post-operative completed the survey over an 11-month study period (females = 11; males = 16; mean age= 22.5 years; range = 17-52). Typologically, metamorphosizers dominated, 48%, followed by shedders, 30%, evolvers, 13% and pragmatists, 9%. This indicates that most patients, 78% (metamorphosizers and shedders) had high expectations of psychological change pre-operatively [X2 (2, N = 90) = 43.9, p &amp;lt; .0001)] and perceptions of psychological change post-operatively [X2 (2, N = 90) = 48.8, p &amp;lt; .0001)]. Conclusions Most patients in this study anticipated and perceived psychological changes after orthognathic surgery. Understanding patient typology may help the orthognathic surgeon understand, address and improve post-operative psychological outcomes in their patients.

Practical utility of the three-dimensional approach in orthognathic surgery.

During recent decades, the three-dimensional (3D) approach in orthognathic surgery were introduced and adopted in clinical practice, providing practical advantages to orthognathic surgeons. Even when the 3D approach is assessed based on the current state of technological development, it has advantages in orthognathic surgery and has become an essential method. It is not sure what to come next in the development of the 3D approaches, It is clear that the 3D approach represents a milestone in the development of orthognathic surgery.

The Impact of Virtual Surgical Planning on Orthognathic Surgery: A Comparison of 2 Specialties

PURPOSE: Virtual surgical planning (VSP) is the gold standard for preoperative treatment planning for orthognathic surgery.1 Prior to the implementation of VSP, traditional orthognathic preoperative preparation required hours of labor and utilization of a dental laboratory. This often limited orthognathic surgery to providers with dental training. The combination of VSP and 3-dimensional printing has allowed orthognathic surgeons the ability to more accurately and efficiently create treatment plans for these cases.2 This technology has also allowed practitioners such as plastic surgeons to begin to perform orthognathic procedures. This review serves to illustrate how plastic surgeons use VSP and highlight its impact on surgical outcomes and research output within orthognathic surgery. METHODS: A literature search was conducted in the PubMed database to identify all articles published before January 2020 that report perioperative use of VSP technology in orthognathic surgeries. Only articles that were written in English, involved operations on live human patients, and used VSP to plan or assist with orthognathic surgery were included in the analysis. All articles that fit inclusion criteria were reviewed to determine the year of publication, type of orthognathic surgery performed, how VSP was used, and the primary outcomes measured. RESULTS: A total of 419 publications regarding VSP in orthognathic surgery resulted from initial search. Of them, 244 publications were authored by oral and maxillofacial surgeons, 28 publications by plastic surgeons, and 34 by surgeons with training in both fields. TEMPORAL TREND OF PUBLICATIONS: Prior to the late 1990s, VSP in orthognathic surgery publications was primarily authored by oral and maxillofacial surgeons. Plastic surgeons first began publishing on VSP technology for orthognathic surgery in 1998. Since then, there has been a rising trend in plastic surgery usage of VSP paralleled by increasing VSP publications in the field, with 2 publications before the year 2010 (7.2%), 9 from 2010 to 2015 (32%), and 18 between 2015 and 2019 (64%). CATEGORIES OF PUBLICATIONS: Most publications from oral and maxillofacial trained surgeons highlight optimal positioning of craniofacial bones, anticipated stability and functionality of occlusion, and the interplay between orthodontic treatments and orthognathic surgery. In contrast, plastic surgeon authored papers often discuss postoperative facial aesthetics by ensuring facial symmetry and treatment especially in the cases of congenital craniofacial abnormalities like cleft lip/palate, Treacher-Collins, and hemifacial microsomia. CONCLUSIONS: VSP is an increasingly utilized tool that reduces the workflow without compromising accuracy and outcomes in orthognathic surgery. This is the first paper to create a temporal relationship between a new technology and the emergence of plastic surgeons into a field typically predominated by oral and maxillofacial surgeons. As plastic surgeons become more familiar with this technology, they have produced literature that provides alternative perspectives on orthognathic surgery that will push the field forward. REFERENCES: 1. Langdon J, Patel M, Brennan P. Operative Oral and Maxillofacial Surgery. 2nd ed. CRC Press; 2010. 2. Baker SB, Goldstein JA, Seruya M. Outcomes in computer-assisted surgical simulation for orthognathic surgery. J Craniofac Surg. 2012;23:509–513.

Understanding orthodontic treatment seems to be the characteristic most valued by orthodontists who refer patients to orthognathic surgeons

Understanding orthodontic treatment seems to be the characteristic most valued by orthodontists who refer patients to orthognathic surgeons

The role of mandibular stabilization in orthognathic surgery

Stability of the temporomandibular joint (TMJ) structure is a critical requirement for treatment that includes orthognathic surgery. If the condyles are not positioned properly in the articular fossae during the manual positioning of the condyle or the intermaxillary fixation, postoperative relapse can result. However, it is difficult for the orthognathic surgeon to control the positioning of the mandibular condyles during orthognathic surgery due to muscle relaxation and the harsh intraoperative environment. Well-managed presurgical orthodontic treatment does not always guarantee the proper positioning of the proximal segment either, especially if the TMJ structures are not stable in their functional area. Therefore, the mandible should be stabilized with a presurgical stabilization splint to provide proper stimulation that forms a pseudodisc in the TMJ structures before surgical procedures.

What characteristics do orthodontists desire in orthognathic surgeons?

The purpose of our study was to report and rank orthognathic surgeon characteristics as valued by referring orthodontists. This was a cross-sectional study surveying orthodontists registered with the American Academy of Orthodontists' Partners in Research program. Survey items gathered information on both orthodontist characteristics and perceptions across 9 surgeon characteristics. Descriptive statistics were computed for all survey items, and linear regression models were used to evaluate the association between orthodontist characteristics and number of orthognathic surgeries performed. Among the 1300 surveyed orthodontists, there were 172 respondents (13% response rate). The majority of orthodontists (66.9%) had had at least 15 years of practice experience, completed between 1 and 5 surgical cases in the past year (55.6%), and referred their orthognathic cases to an oral and maxillofacial surgeon (99.4%). Among orthodontists, only practice experience (P < .01) was independently associated with the number of surgeries performed. An understanding of preoperative and nonoperative orthodontics was the most highly valued surgeon characteristic, and 50% of all respondents listed it as one of the most important characteristics. The next most valued surgeon characteristics were the ability to lead surgical treatment planning, acceptance of patient insurance plans, and sharing of strong personal and professional relationships. The most desirable characteristic in an orthognathic surgeon, as stated by the surveyed orthodontists, was an understanding of both preoperative and nonoperative orthodontics. Surgeons seeking to increase orthognathic referrals should work to increase insurance coverage and actively initiate strong personal and professional relationships with orthodontists.

Trauma-Induced Unilateral Buccal Nonocclusion.

Buccal nonocclusion is a difficult situation for orthognathic surgeons. This is the severest form of crossbite with congenital or traumatic origin. Unilateral cases are more difficult and need more attention. Posttrauma-acquired buccal nonocclusion is easier for management than congenital cases that need orthodontic preparation and more complicated orthognathic surgeries. Two cases of trauma-induced unilateral buccal nonocclusion are presented with different etiologies. Preoperative model surgery and posterior segmental surgery are keys to correct trauma-induced buccal nonocclusion.

What are the defining characteristics of the most cited publications in orthognathic surgery?

The purpose of this study was to identify the characteristics associated with highly cited papers in orthognathic surgery. This was a cohort study of articles published in the English-language literature from 1900 to 2017. Citation databases were searched for papers related to orthognathic surgery and the most frequently cited papers were identified. For each paper, the following variables were collected: region of origin, time-period of publication, corresponding author specialty, journal of publication, topic area, study design, and number of citations. The outcome variable was the citation index (citations per year). North American investigators published 70% of the 100 most-cited articles in orthognathic surgery. The majority of papers were from oral and maxillofacial surgeons. Frequent content areas were diagnosis, virtual planning, fixation/stability, and complications. The majority (54%) of studies were cohort or case report/series. The mean number of citations was 235.0±126.5; the mean citation index was 9.9±6.1 citations per year. Time-period, content area, and study design were associated with the citation index (all P<0.001). Time-period, content area, and study design predicted the citation index (all P≤0.009). Among frequently cited papers in orthognathic surgery, oral and maxillofacial surgeons had the highest volume of contributions. Diagnosis, treatment planning, and complications were the most common topics studied.

Identification of ‘Point A’ as the prevalent source of error in cephalometric analysis of lateral radiographs

Deviations in measuring dentofacial components in a lateral X-ray represent a major hurdle in the subsequent treatment of dysgnathic patients. In a retrospective study, we investigated the most prevalent source of error in the following commonly used cephalometric measurements: the angles Sella-Nasion-Point A (SNA), Sella-Nasion-Point B (SNB) and Point A-Nasion-Point B (ANB); the Wits appraisal; the anteroposterior dysplasia indicator (APDI); and the overbite depth indicator (ODI). Preoperative lateral radiographic images of patients with dentofacial deformities were collected and the landmarks digitally traced by three independent raters. Cephalometric analysis was automatically performed based on 1116 tracings. Error analysis identified the x-coordinate of Point A as the prevalent source of error in all investigated measurements, except SNB, in which it is not incorporated. In SNB, the y-coordinate of Nasion predominated error variance. SNB showed lowest inter-rater variation. In addition, our observations confirmed previous studies showing that landmark identification variance follows characteristic error envelopes in the highest number of tracings analysed up to now. Variance orthogonal to defining planes was of relevance, while variance parallel to planes was not. Taking these findings into account, orthognathic surgeons as well as orthodontists would be able to perform cephalometry more accurately and accomplish better therapeutic results.

Sequent therapy for adenoidal and tonsillar hypertrophy patients with OSDB

Children suffering from adenoidal and tonsillar hypertrophy are very common, the hypertrophy of adenoid and tonsil could obstruct the upper airway to cause mouth breathing,as a result, some dentofacial deformities are developed. The key reason for these deformities is mouth breathing. For the children with adenoidal and tonsillar hypertrophy, T&A is just the first step for treatment, most patients need a sequent treatment by the doctors from multiple departments, such as ENT doctors,orthodontics doctors,orthognathic surgeon. The earlier the treatment begins, the better the effect is.

Reinventing the wheel: a modern perspective on the bilateral inverted ‘L’ osteotomy

The bird-face deformity of a severe class II, high Frankfort–mandibular plane angle with significant retrogenia, often associated with diminutive condyles and reduced posterior face height, poses many challenges to the orthognathic surgeon. Of greatest concern in these patients is the degree of mandibular advancement required and the potential for relapse. The sagittal split osteotomy is the workhorse of mandibular surgery but does not allow significant lengthening of the ramus, which is desirable in this group of patients. An inverted ‘L’ osteotomy of the mandible to facilitate ramus lengthening is therefore indicated in the management of this group, but is a procedure that has largely fallen out of favour due to the need for an extraoral approach and intermaxillary fixation. The advent of distraction osteogenesis promised to be the answer for these cases, but with nearly 20 years of experience with these techniques, it is clear that it does not represent the panacea that was hoped for. We present a series of four cases of bimaxillary surgery consisting of maxillary osteotomy and bilateral inverted ‘L’ osteotomy of the mandible carried out via an intraoral approach (average advancement 10.5mm), where internal semi-rigid fixation was employed to obviate the need for intermaxillary fixation. We highlight the indications for this procedure and why it is ideally suited to this group of patients and argue that the procedure should be re-introduced to the armamentarium of the orthognathic surgeon.