Orthognathic Surgery Research Articles

Does the Timing of Orthognathic Surgery Affect the Level of External Root Resorption?: Surgery-First Approach Versus Conventional Orthognathic Surgery.

This study aimed to compare external root resorption levels, both linearly and areally, on panoramic radiographs in Class III patients whose treatment was completed with the conventional orthognathic surgery and the surgery-first approach. The study included 20 patients (10 female, 10 male; 23.98±2.63y) treated with conventional orthognathic surgery and 18 patients (8 female, 10 male; 27.5±3.42y) treated with surgery-first approach was included. Linear and area measurements were made on the digital panoramic radiographs taken before and at the end of the treatment of 38 patients who constituted the sample of the study. The mean changes observed in each group were evaluated using a paired t test. The chronological ages, skeletal features (type of Class III malocclusion), treatment durations, initial values, and mean changes that occurred in each group were compared using independent t test. When the changes in root lengths and root surface areas were evaluated in all teeth in both groups, a significant loss in size was measured (P<0.001). More resorption was observed in teeth 12 and 22 in the conventional surgery group (P<0.05). When the amount of resorption in both groups was compared, there was significantly more resorption in tooth number 12 in the conventional surgery group (P<0.05). The study showed that there was external root resorption in all teeth in both protocols, but the root lengths of the lateral teeth were shortened more in both groups.

Quantification of facial symmetry in orthognathic surgery: A novel approach integrating 3D contour maps and hyper-dimensional computing

This study aimed to enhance the evaluation of facial symmetry crucial for planning and assessing outcomes of orthognathic surgery (OGS). An innovative approach combining three-dimensional (3D) facial contour lines with hyperdimensional (HD) computing was developed for this purpose. Data were collected using 3D cone beam computed tomography (CBCT) at Chang Gung Memorial Hospital from 2016 to 2021. A comprehensive dataset was compiled, including images from 150 normal individuals and 2500 patients, totaling 5150 preoperative and postoperative facial images. A machine learning model was trained to analyze these images, and 3D contour data were used to create a facial symmetry quantification system with HD computing. Additionally, 3D CBCT data from 200 patients before and after OGS were retrospectively reviewed for clinical application. The developed facial symmetry algorithm demonstrated an overall accuracy of 84.1 %. Postoperative facial symmetry scores improved significantly, with a mean score increase of 53 %, from 2.40 to 3.63. The study culminated in the creation of a web-based system that leverages HD computing and 3D contour mapping to automate facial symmetry assessment. This system offers a user-friendly interface for rapid and accurate evaluations, facilitating better communication between clinicians and patients.

Screening of Sensorial and Inflammatory Changes in Patients Submitted to Orthognathic Surgery.

Despite the high levels of success after orthognathic surgery, the immediate postoperative pain and edema, besides the neurosensorial deficits, are common complications. This study aimed to evaluate the pattern of sensory and inflammatory responses in patients undergoing orthognathic surgery. This prospective observational study included 20 patients undergoing bimaxillary orthognathic surgery, who were evaluated in the preoperative period and on Days 1, 2, 3, 4, 5, 6, 7, and 30 after surgery, using a battery of tests to assess sensorial and inflammatory changes. Subjective and objective evaluations of edema indicated a trend toward edema resolution within 30 days, with a significant decrease in mouth opening on days 1, 7, and 30 after surgery. Regarding nasal obstruction, a significant increase in Nasal Obstruction Symptom Evaluation (NOSE) scores was demonstrated on the first, second, and third days, returning to preoperative levels after 30 days. There was a significant increase in visual analogic scale (VAS) scores from the first to the seventh day after surgery, with a reduction within 30 days. For mechanical and thermal sensitivity tests, the lower lip and chin regions had poorer results, without recovery after 30 days. Positive correlations were observed between painful and inflammatory parameters, as well as between subjective and objective evaluations. Analysis of saliva biomarkers did not show significant differences for pre- and postoperative CCL3 or CCL4 levels. Data provide new evidence about the early inflammatory and sensorial complications after orthognathic surgery.

Limitations of orthodontic treatment: Class III camouflage

Class III malocclusion treatment planning in the non-growing patient can represent a challenge. The options of whether to attempt orthodontic camouflage or to treat with orthognathic surgery are affected by numerous factors, including the severity of the underlying skeletal relationship, the dento-alveolar compensation already present, the facial aesthetics, the patient's concerns and expectations, and the anatomical limits of orthodontic tooth movement. Numerous studies have tried to provide guidance by looking at the differences between groups of patients to determine whether they should be treated orthodontically or surgically. However, owing to the retrospective nature of these studies and their heterogeneity, they prove less helpful than desired. In this narrative review, the authors will look at these studies to provide some guidance for the orthodontist. CPD/Clinical Relevance: Treatment planning in Class III malocclusions can be challenging owing to the numerous factors that must be considered.

Masticatory function and three-dimensional facial morphology of soft tissues: One year after orthognathic surgery

ObjectiveDentofacial deformities (DFD) require orthodontic treatment, orthognathic surgery, and speech therapy for aesthetic and functional problems. This longitudinal study analyzed changes in masticatory function and three-dimensional (3D) facial soft tissue in patients with Class II and Class III DFD after orthognathic surgery. In addition, the study investigated the relationship between facial measurements, maximum bite force (MBF), and orofacial myofunctional status (OMS). DesignThe sample consisted of 46 participants, including 10 patients with Class II DFD, and 11 patients with Class III DFD. These groups were assessed before (T0) and 6 months (T1) after surgery. Twelve patients who completed the treatment protocol were evaluated 12 months post-surgery (T2). The patient groups were compared with each other and with a control group (CG) of 25 healthy subjects. The participants underwent MBF and clinical evaluation of OMS, including masticatory behavior, using a validated protocol. The 3D facial soft tissue was assessed using laser scanning. ResultsCompared to the CG, DFD patients showed reduced MBF, masticatory behavior, and OMS scores at T0. At T2, there was an improvement in MBF, masticatory, and OMS scores, but differences were observed compared to the CG. Changes in facial soft tissue followed the underlying hard tissue movement resulting from surgery, and reduction of vertical measurements contributed to improvements in masticatory function. ConclusionThese findings indicated that combined surgery, orthodontic treatment, and speech therapy can lead to a significant improvement in masticatory function and facial soft tissue in DFD patients, although not completely 12 months post-surgery.

Tranexamic Acid Reduces Blood Loss in Orthognathic Surgery – a Systematic Review and Meta Analysis

Tranexamic Acid Reduces Blood Loss in Orthognathic Surgery – a Systematic Review and Meta Analysis

Comparison of static teeth exposure in different postures and its influencing factors of orthognathic surgery patients.

This study aimed to explore the differences and influencing factors of static teeth exposure in different postures of orthognathic surgery patients. A total of 148 patients were collected before or after orthognathic surgery. Photographs were taken in the upright and supine positions, and the static teeth exposure values were measured to compare whether the difference among different positions was statistically significant. The patients were classified in accordance with gender, presence or absence of orthodontic brackets, measurement time (preoperative or postoperative), and maxillary movement direction (forward or backward), and the difference of static teeth exposure was compared. The correlation between the difference of static teeth exposure and age was analyzed. The diffe-rence of static teeth exposure between the two positions was 0.99 mm±0.95 mm, which was statistically significant (P=0.000). A statistical difference in the difference of static exposure was observed between female and male (P<0.05). No statistical difference in the difference of static exposure was observed among orthodontic brackets, preoperative or postoperative time points, and maxillary movement direction. In addition, no significant correlation was found between the difference of static teeth exposure and age (r=-0.087, P=0.291). Compared with the upright position, the static exposure of teeth increased by approximately 0.99 mm in the supine position. The difference of static exposure under different postures was greater in males than in females. Furthermore, orthodontic bracket, maxillary surgery, maxillary movement direction, and age had no effect on the difference of static teeth exposure in different postures.

Three-dimensional Analysis of Skeletal Stability in Cleft Lip and Palate Patients Undergoing Bimaxillary Surgery With Le Fort I Osteotomy and Intraoral Vertical Ramus Osteotomy.

Orthognathic surgery in patients with lip and palate clefts is challenging owing to scar tissue from primary repairs and severe deformities. In this study, we evaluated the stability of Le Fort I osteotomy with intraoral vertical ramus osteotomy (IVRO) in patients with cleft lip and palate using 3-dimensional (3D) analysis. This retrospective study comprised 14 cleft lip and palate patients (3 females, 11 males; the average age at surgery: 23.8y) who underwent bimaxillary orthognathic surgery involving Lefort I osteotomy and IVRO. Cone-beam computed tomography (CBCT) images were obtained at preoperative (T0), 1-month postoperative (T1), and 1-year follow-up (T2) periods. The 3D analysis assessed the transitions and rotations of the maxilla and mandible using a virtual triangle. The maxilla showed stability in all directions at the 1-year follow-up with minimal relapse. The distal segment of the mandible exhibited clinically acceptable anterior (1.15mm relapse) movements and pitch rotation (2.88° counterclockwise relapse) during the first year postoperatively. The proximal mandibular segment underwent anterior-inferior transition (1.21 and 2.01mm, respectively) and lateral-outward rotation (4.90° and 7.51°, respectively) postsurgery, remaining unchanged 1 year postoperation. Le Fort I osteotomy with IVRO provides skeletal stability in patients with cleft lips and palates. This study demonstrated a minimal maxillary relapse and clinically acceptable movements in the distal mandibular segment during the first postoperative year. The proximal mandibular segment moved anteriorly and inferiorly, rotated laterally and outward after surgery, and remained unchanged at the 1-year follow-up.

Rationale to consider either Orthodontic treatment or Orthognathic surgery

Rationale to consider either Orthodontic treatment or Orthognathic surgery

Assessment of biomechanical strength of titanium versus unsintered-hydroxyapatite/poly-L-lactic acid (u-HA/PLLA) osteosynthesis screws in bilateral sagittal split ramus osteotomy

Titanium osteosynthesis is considered to be stable for the bilateral sagittal split ramus osteotomy (BSSRO) procedure in orthognathic surgery but is disregarded owing to a multitude of complications, the most significant necessitating a secondary surgery for removal. Bioresorbable osteofixation devices, especially third-generation unsintered-hydroxyapatite/poly-L-lactic acid (u-HA/PLLA), are increasingly used in the mandibular region because of their strength and bioactive/osteoconductivity. To date, three titanium bicortical screws has been the standard for the rigid fixation of BSSRO. As data on the use of u-HA/PLLA bicortical screws are limited, we conducted an in vitro biomechanical strength test to evaluate the performance of 12-mm bicortical u-HA/PLLA screws in comparison with titanium screws using mandibular bone models. BSSRO was performed on all specimens, followed by fixation with either three titanium screws or three, four, or five u-HA/PLLA screws, and loading was performed using a clinically presumed occlusal force. Displacement forces (measured in newton ‘N’) of 50N, 130N, and 220N were applied. Our results showed that the use of three u-HA/PLLA screws was unstable, that of four u-HA/PLLA screws was comparable, and that of five u-HA/PLLA screws provided stability equal to that of the three titanium bicortical screws. Although further clinical assessment is needed, our study demonstrated that the five u-HA/PLLA bicortical screws are viable alternatives to titanium in BSSRO osteofixation.

ScholarGPT's performance in oral and maxillofacial surgery

ObjectiveThe purpose of this study is to evaluate the performance of Scholar GPT in answering technical questions in the field of oral and maxillofacial surgery and to conduct a comparative analysis with the results of a previous study that assessed the performance of ChatGPT. Materials and MethodsScholar GPT was accessed via ChatGPT (www.chatgpt.com) on March 20, 2024. A total of 60 technical questions (15 each on impacted teeth, dental implants, temporomandibular joint disorders, and orthognathic surgery) from our previous study were used. Scholar GPT's responses were evaluated using a modified Global Quality Scale (GQS). The questions were randomized before scoring using an online randomizer (www.randomizer.org). A single researcher performed the evaluations at three different times, three weeks apart, with each evaluation preceded by a new randomization. In cases of score discrepancies, a fourth evaluation was conducted to determine the final score. ResultsScholar GPT performed well across all technical questions, with an average GQS score of 4.48 (SD=0.93). Comparatively, ChatGPT's average GQS score in previous study was 3.1 (SD=1.492). The Wilcoxon Signed-Rank Test indicated a statistically significant higher average score for Scholar GPT compared to ChatGPT (Mean Difference = 2.00, SE = 0.163, p < 0.001). The Kruskal-Wallis Test showed no statistically significant differences among the topic groups (χ² = 0.799, df = 3, p = 0.850, ε² = 0.0135). ConclusionScholar GPT demonstrated a generally high performance in technical questions within oral and maxillofacial surgery and produced more consistent and higher-quality responses compared to ChatGPT. The findings suggest that GPT models based on academic databases can provide more accurate and reliable information. Additionally, developing a specialized GPT model for oral and maxillofacial surgery could ensure higher quality and consistency in artificial intelligence-generated information.

Nonsurgical correction of occlusal canting using temporary anchorage devices: A systematic review

ObjectiveThe recent development of temporary anchorage devices (TADs) allows orthodontic canting correction by selective intrusion of the molars. The purpose of this study was to review the treatment strategy and outcomes after orthodontic correction of occlusal canting using the TADs based on published literature including the case reports. Materials and methodsA systematic review of published English-language human clinical studies was conducted by electronic search of PubMed, Embase & Medline, and Scopus reviews up to Dec 2023. For inclusion, reports required documentation of subject demographic characteristics; location or type of TADs; diagnosis; presence of maxillary occlusal canting (MOC); and treatment outcomes (MOC correction). Studies were excluded if they involved orthognathic surgery to correct MOC. Critical appraisal for all included studies were conducted with the case reports/case series appraisal checklist of the Joanna Briggs Institute (JBI). The current study was registered in PROSPERO (CRD42021226432). ResultsThe search identified 260 reports and a total of 33 case reports met inclusion criteria with 46 individual patient cases. The results reported that occlusal canting could be resolved by unilateral intrusion of maxillary posterior teeth using TADs. The reported the amount of maxillary molar intrusion ranged from 1 mm to 4.8 mm. However, there were fundamental limitations in study subjects, paucity of data regarding the long-term stability, lack of standardization in intrusion mechanics, and variations in TAD devices. ConclusionsAlthough the previous reports mentioned that orthodontic canting correction with TADs could avoid maxillary surgery or orthognathic surgery itself, it cannot be concluded that non-surgical correction of occlusal canting can be comparable to surgical treatment. Further comparative investigation between surgical and nonsurgical canting correction is needed to clarify whether orthodontic intrusion can be an alternative to surgical canting correction in terms of efficacy and stability.

Effect of maxillary advancement on velopharyngeal function in cleft lip and palate: 20 years of experience

This retrospective study aimed to investigate the impact of orthognathic surgery with maxillary advancement (MA) on the velopharyngeal function (VF) in individuals with cleft lip and palate (CLP).The study included 651 patients with repaired CLP, both sexes, aged over 18 years who underwent MA alone or in combination with nasal procedures and/or mandibular osteotomy, operated between 2000 and 2019. The main outcome measures were nasalance (nasal text-NT and oral text-OT) and velopharyngeal orifice area measurement (VA), determined by nasometry and pressure-flow technique, respectively.Preoperatively, mean nasalance scores for NT and OT indicated normality, and VA demonstrated borderline-inadequate velopharyngeal closure in all patients. Following MA, a significant increase in nasalance scores for NT and OT occurred (p < 0.001), revealing hypernasality in those undergoing MA combined with nasal procedure (MAN, N = 191), bimaxillary orthognathic surgery with nasal procedure (BON, N = 227) and bimaxillary orthognathic surgery (BO, N = 151). Conversely, nasalance scores remained within the normal range for those undergoing isolated maxillary advancement (IMA, N = 82). VA exhibited a significant increase leading to the classification of VF as inadequate in the BON and MAN groups. Overall, MA contributed to VF deterioration, resulting in the appearance of hypernasality and increased VA, particularly when combined with nasal procedures.

Is minimally invasive approach to genioplasty predictable for mentolabial soft tissue? A retrospective cohort study

IntroductionThe aim of this study was to conduct a three-dimensional analysis of the effects on mentolabial soft tissues of three different orthognathic surgery protocols: bimaxillary surgery without genioplasty, bimaxillary surgery with conventional or minimally invasive genioplasty (MIS). Materials and methodsPre-operative and post-operative CBCT were superimposed to quantify and ascertain the direction of mandibular movements, and soft tissue were analyzed to evaluate the hard to soft tissue ratio. Data from 97 consecutive patients were evaluated: 30 conventional genioplasty, 36 MIS and 31 no genioplasty. ResultsThe impact of the surgical movements on the overlying soft tissues can be consider with stronger correlation in the group No Genioplasty in the whole mentolabial region, stronger correlation in labial and pogonion region in the MIS group and no stronger correlation in the conventional group. ConclusionsSutures in the mentolabial region directly interfere with the postoperative impact of orthognathic surgery on soft tissues in mentolabial area, in both the vertical and horizontal directions. A smaller incision – consequently involving less detachment of soft tissues in the region – may promote a lower risk of chin ptosis, in addition to greater suspension of the musculature.

The Most Influential Publications in Oral and Maxillofacial Surgery Over the Past Decade

Reliable metrics are needed to measure the impact of academic publications in order to fully understand and evaluate the contributions of articles published in the field of oral and maxillofacial surgery(OMFS). The aim was to identify and analyze the top 100 articles each year, with the highest Field-Weighted Citation Impact(FWCI) and citation counts, in the field of OMFS over the past decade, totaling 1,000 articles. The research was conducted on April 20, 2024, using the Scopus database. It identified the top 100 articles each year with the highest FWCI from the top six journals with the highest metric scores in OMFS, totaling 1,000 articles. The citation counts of these publications in Google Scholar were also recorded. The predictor variable was the articles. The primary outcome variable was the FWCI value, while the secondary outcome variable was the number of citations. The covariates were the journals in which the articles were published, the publication year, the type of document, the type of access policy, and the subject of the research. There was a weak positive correlation between FWCI and citation count(rho = 0.083, P = .009). All covariates significantly affected FWCI(P < .005), while all but access policy significantly affected citation count(P = .167). The highest average FWCI(6.31 ± 5.51) was observed in the Journal of Stomatology, Oral and Maxillofacial Surgery(JSOMS), and the highest citation count was found in the Journal of Oral and Maxillofacial Surgery(JOMS)(61.5 ± 126.4). Orthognathic Surgery and Dentofacial Deformities were the scientific fields with the most publications(14 %). COVID-19 and Artificial Intelligence had the highest FWCI(8.65 ± 10.98 and 7.68 ± 6.42, respectively). MRONJ had the highest average citation count(88.6 ± 254). This study demonstrates that using both FWCI and citation count metrics can more accurately assess the impact of academic publications in the field of OMFS. These findings can serve as a guide for future research and contribute to strategic decisions aimed at improving clinical practices and patient care.

Advances in the Treatment of Congenital Infiltrating Lipomatosis of the Face: The Role of PIK3CA Mutations and Microvascular Reconstruction

Congenital infiltrating lipomatosis of the face is a rare aggressive-benign disorder characterized by progressive hemifacial overgrowth and complex, often asymmetrical, facial differences. Recently linked with the PIK3CA-Related Overgrowth Spectrum, it arises from mosaic mutations in the PIK3CA gene. Treatment, largely supportive and tailored to individual clinical presentations, requires a multidisciplinary approach. This article reviews the longitudinal care of a young adult patient from 8 years of age, detailing his journey through combined orthognathic and microvascular reconstructive surgery and the outcomes thereof. In addition, it explores the treatment’s implications in the context of the PIK3CA mutation, offering insights into potential prognostic and therapeutic considerations.

Biofluorescence imaging system (BIS) Guided surgery for MRONJ: A Case Series on the Preservation of Teeth and Implants: Biofluorescence imaging system guided MRONJ surgery

The decision of surgical margin for Medication-Related Osteonecrosis of the Jaw (MRONJ) surgery is challenging. Recently, a method involving biofluorescence imaging system (BIS) has been reported for its application in MRONJ surgery to live detection of pathologic bone tissue from vital bone, which cannot be distinguished during conventional surgery. This case series aimed to assess the outcomes of adjacent teeth and implants near the lesion site in MRONJ patients who underwent BIS-guided MRONJ surgery. This retrospective study was assessed the radiographic and clinical outcomes of seven patients who underwent MRONJ surgery with BIS guidance but chose not to remove adjacent teeth or implants near the lesion. A total of seven patients (1 male, 6 females, 77.2 ± 4.7 years) were included in the study. Four implants and four teeth adjacent to the lesion were preserved. Over an average duration of 8.7 months, all subjects exhibited normal soft tissue healing and function without any complications. In conclusion, the BIS guided MRONJ surgery can be considered a minimally invasive and effective approach.

Impact of protraction or orthognathic surgery for class III malocclusion on longitudinal quality of life in patients with cleft lip and palate.

This study assessed overall quality of life (QoL) over time in youth with cleft lip and palate (CLP) undergoing maxillary protraction treatment or orthognathic surgery for class III malocclusion to identify any differences in QoL based on treatment group and outcome success. A prospective longitudinal cohort study was conducted in two pediatric hospitals. The Short Form Health Survey (SF-12) measured physical and mental QoL prior to treatment, at maximal correction, at treatment completion, and at 1-year post treatment. Analyses included one-sample, two-sample, and paired t-tests and analyses of variance and covariance. Participants (N = 91) either completed protraction (n = 53) at age 11-14 or surgery (n = 38) at age 16-21. Participants were mostly Latinx (67%) males (55%) born with unilateral CLP (81%) and there were no demographic differences between the two groups other than age. The total sample's QoL was in the average range and significantly higher than national norms. No significant differences were found in QoL-based outcome success; however, the protraction group showed a gradual physical QoL improvement over time, while the surgery group experienced a temporary drop in physical QoL postoperatively. At treatment completion, higher physical QoL was associated with higher socioeconomic status. At a year post treatment, mental QoL was significantly higher for males. Both protraction and surgery appear to be acceptable treatment options in terms of overall QoL for youth with CLP. While treatment success did not impact QoL, there were some differences in physical QoL coinciding with the treatment phase as well as individual factors.

A novel electromagnetic-navigated maxillary repositioning system for Le Fort I osteotomy: Preclinical evaluation

PurposeAdvancements in surgical assistive technologies for orthognathic surgery have increased the prevalence of guided surgeries. This study developed and evaluated a novel system utilizing electromagnetic (EM) navigation for maxillary positioning. MethodsLe Fort I osteotomies were performed on three skull models. The three-dimensional position of two sensors, facilitated by an EM tracking system, was used to move and fix the maxilla in its planned position, shifted 3 mm forward. The first sensor was placed on the lateral border of the pyriform aperture on the cranial side, while the second sensor was affixed as a splint on the maxillary dentition. Surface data from scans of the experimental skull bone were obtained using an optical scanner and superimposed on the pre-planned data to assess accuracy. ResultsThe discrepancy between the maxilla positioned with EM navigation and the planned position was within 1.0 mm in the vertical, horizontal, and anteroposterior directions. Error at the A and ANS measurement points was 0.44 and 0.54 mm, respectively (average = 0.49 mm). ConclusionThis experimental study represents a paradigm shift from guided to navigation surgery. Meticulous maxillary repositioning achieved through EM navigation enhances the reproducibility of preoperative simulations during surgery.

Satisfaction questionnaire survey after surgical orthodontic treatment in patients with jaw deformities

ObjectiveSurgical orthodontic treatment leads to morphological, functional and psychological changes in patients with jaw deformities. For the evaluation of outcomes of surgical orthodontic treatment from the patient's point of view, a questionnaire survey was performed after treatment and factors affecting patient satisfaction were examined. MethodsA survey by mailing questionnaires that each consisted of 30 items was conducted in 250 patients with jaw deformities who underwent orthognathic surgery in our department during the period from January 2015 to December 2020. Eighty-four patients responded (response rate of 34.0%). The patients who responded included 24 males and 60 females. The mean age at the time of surgery was 26 years. ResultsFifty-four patients complained of morphological abnormalities such as facial appearance and malocclusion, and 30 patients complained of functional disturbances such as masticatory disabilities. Eighty-two patients were satisfied with the outcome of surgery, but there were two patients with postoperative paresthesia and residual facial asymmetry who were not satisfied with the outcome. Improvements were observed in mastication and pronunciation in 74 and 46 patients, respectively. Psychologically, 26 patients showed positive personality changes postoperatively. Thirty-three patients had TMJ symptoms before surgery, and the symptoms were resolved after surgery in 24 of those patients. Two patients developed snoring during sleep after surgery. ConclusionsThis survey showed that most patients with jaw deformities were satisfied with the results of surgical orthodontic treatment.