Orthognathic Surgery For Class Research Articles

A Bibliometric Analysis of Class III Malocclusions in Orthognathic Surgery Publication Trends From 1987 To 2023

Objective: The aim of this study is to conduct bibliometric analysis on orthognathic surgery in class III malocclusions, a frequently investigated topic in orthodontics. Methods: The study analyzed all articles in the Web of Science database from March 1987 to June 2023 using VOSviewer software (version 1.6.14). Initially, all 1173 articles were analyzed in the Web of Science browser and later exported for further analysis in the VOSviewer program. The VOSviewer program was utilized to map relationship networks based on co-authorship, co-occurrence, citation, bibliographic coupling, or co-citation links. Additionally, the study examined the distribution of publications by year, analyzed articles related to keywords, identified authors with the most publications on these topics, and compiled the 10 most cited articles containing the words "orthognathic surgery" and "class III" in the title, abstract, and keywords using the Web of Science browser. Results: The most publications on these topics were published in 2022. Seung-Hak Baek was the most cited author (413 citations). Chang Gung University ranked highest in terms of citations (729 citations) and had the most extensive publication record (60 articles) in the bibliometric network map. South Korea led in both article production (227 articles) and citation count (2587 citations). Conclusions: Orthognathic surgery for class III malocclusion has gained significant attention over the years due to technological advancements and increasing aesthetic concerns among patients. The interest in this field is expected to grow, leading to more studies exploring related applications and topics.

Highlights of orthognathic surgery in class II patients: a systematic review

Introduction: Orthognathic surgery is indicated to modify the position of the maxillomandibular structure, which may cause changes in the sagittal position of the mandibular condyle in individuals with retrognathism and mandibular prognathism. In the context of orthognathic surgery, anterior open bite (AOB) is an easily recognized malocclusion and presents only aesthetic and functional problems. Objective: Foi desenvolver uma revisão sistemática para apresentar as principais considerações da cirurgia ortognática em pacientes classe II. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from October to December 2023 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 88 articles were found, 40 articles were evaluated in full and 20 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 21 studies with a high risk of bias and 21 studies that did not meet GRADE and AMSTAR-2. Most studies did not show homogeneity in their results, with X2=57.5%>50%. The etiology of anterior open bite is multifactorial and may be caused by environmental and hereditary factors. Class II patients may have significantly greater amounts of lateral and inferior translation than class III patients. Two-jaw surgery for open bite correction led to different directions and amounts of condylar rotational displacement in patients with skeletal class II malocclusion. Treatment can be carried out through preventive, interceptive, corrective, or even surgical treatments. The differentiated bonding of brackets to the anterior teeth is also a very useful resource for the treatment of anterior open bite.

Volumetric analysis of pharyngeal airway dimensions and hyoid bone position following orthognathic surgery in skeletal class III patients: a cross sectional cephalometric study

Background: Objective of the study was to determine linear and volumetric changes in pharyngeal airway dimensions in class III patients treated by different modalities of orthognathic surgery and to compare the results of different orthognathic surgical modalities, and determine the change at the position of the hyoid bone. Methods: Pre and post-treatment lateral cephalogram of 53 class III adult patients who were treated by different modalities of orthognathic surgery studied to assess the changes in pharyngeal airway dimensions and hyoid bone position after orthognathic surgery. 28 patients were treated with mandibular set back, and 25 patients were treated with Bijaw surgery. Lateral cephalogram records were taken before treatment (T1), after surgery (T2), the end of the fixed treatment (T3) and 1 year after debonding (T4). Results: Interception of both surgical modalities has significant impact on various skeletal and pharyngeal parameters i.e., BMeH (0.00), PNS (0.009), MPS (0.13), GOP (0.001), IPS (0.007), SAS (0.006), and MAS (0.00). OJ (overjet) and OB (overbite) was significant especially after time interval of one year. In Bijaw groups, PPST4 parameter was significantly increased (0.0000), SPST4 (0.000), GOP (0.000), EPS (0.000) and IPS parameter was significantly decreased (0.045). Significant difference was observed in T4 time interval in superior pharyngeal airway space, posterior airway space and middle airway space with (p<0.05). Conclusions: Pharyngeal airway is significantly altered following orthognathic surgery in class III patients and it depends on the type of surgical modality employed were Bijaw surgery has significant impact on oropharyngeal and hypopharyngeal airway space.

Correlation between condylar, glenoid fossa and joint space changes two years after bimaxillary orthognathic surgery in class II subjects

The position of the mandible after an orthognathic surgical procedure is believed to be dependent on adaptive condylar and glenoid fossa changes, in addition to condylar positional changes within the fossa. The purpose of this study was to evaluate the association between condylar and glenoid fossa changes and the positional changes in the joint space two years after bimaxillary surgery. The condyles and glenoid fossae were reconstructed from a pair of superimposed pre- and postoperative (two years) cone-beam computerized tomography scans. The surface models were spatially divided into four regions. Three-dimensional morphological and positional changes were measured as volumetric differences and surface distances between the pre- and postoperative condylar and glenoid fossa regions. Statistical associations of condylar, glenoid fossa and joint space changes were calculated by Pearson's correlation coefficient. Twenty subjects (sixteen female; four male; mean age 27.6 years) with class II malocclusion and maxillomandibular retrognathia, who underwent bimaxillary surgery, were assessed. A strong and statistically significant correlation between condylar and glenoid fossa changes was observed two years after surgery (r = 0.52, p < 0.001). The correlation was strongest and statistically significant anterior-medially (r = 0.48, p = 0.002) and anterior-laterally (r = 0.38, p = 0.015). Condylar changes were significantly correlated with the increase in the posterior-medial (r = 0.37, p < 0.020) and the posterior-lateral (r = 0.45, p < 0.003) joint space distances. Changes of the condyle, the glenoid fossa and the joint space following bimaxillary surgery were significantly correlated in these class II subjects.

Risk factors for postoperative facial swelling at 1 week after bimaxillary orthognathic surgery in Class III patients

ObjectiveTo quantify facial swelling at 1 week after Le Fort I osteotomy and bilateral sagittal splitting ramus osteotomy in Class III patients and to identify factors contributing to the swelling based on clinical, morphologic, and surgical variables. Study DesignData from 63 patients were examined in this single-center, retrospective study. Facial swelling was quantitatively measured by superimposing computed tomography data taken in the supine position at 1 week and 1 year postoperatively and extracting the area of maximum intersurface distance. Age, sex, body mass index, thickness of subcutaneous tissue, and of masseter muscle, maxillary length (A-VRP), mandibular length (B-VRP), and posterior maxillary height (U6-HRP), surgical movement (ΔA-VRP, ΔB-VRP, ΔU6-HRP), drainage method, and usage of facial bandages were examined. Multiple regression analysis was performed using the above factors. ResultsThe median swelling at 1 week postoperatively was 8.35 IQR (5.99–11.47) mm. Multiple regression analysis revealed three factors that were significantly associated with facial swelling: Use of postoperative facial bandages (P=0.03), masseter muscle thickness (P=0.03), and ΔB-VRP (P=0.04). ConclusionAbsence of a facial bandage, thin masseter muscle, and large horizontal mandibular movement are risk factors for facial swelling at 1 week postoperatively.

Orthognathic surgery in class II patients and the treatment of obstructive sleep apnea syndrome: a concise systematic review of the clinical studies

Introduction: Obstructive sleep apnea (OSA) is characterized by intermittent partial or complete obstruction of the airways during sleep, being called OSA syndrome (OSA) when associated with daytime/nighttime symptoms and/or comorbidities, such as systemic arterial hypertension or diabetes mellitus. The prevalence reaches 32% in the general population, varies between 1% and 20% when associated with COPD (overlap syndrome), and is described as above 60% in populations with COPD and obesity, Orthognathic Surgery (OS) corrects the deformities of the bones of the maxilla and mandible. Objective: It was to highlight the main considerations and outcomes of clinical studies on the importance of orthognathic surgery in class II patients and the treatment of obstructive sleep apnea syndrome. Methods: The systematic review rules of the PRISMA Platform were followed. The search was carried out from October to December 2022 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases, using articles from 2005 to 2022. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed accordingly, according to the Cochrane instrument. Results and Conclusion: A total of 420 articles were found, 157 articles were evaluated and 25 were included and developed in this systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 103 studies with a high risk of bias and 42 studies that did not meet GRADE. It was concluded that obstructive sleep apnea syndrome is related to comorbidities such as systemic arterial hypertension or diabetes mellitus. Orthognathic surgery treats patients with moderate and severe facial deformities, enabling the achievement of functional balance and harmony in facial aesthetics. Maxillomandibular advancement is an orthognathic surgery procedure that has been used to treat obstructive sleep apnea syndrome. However, maxillomandibular advancement often leads to unsatisfactory esthetic results. Proper early diagnosis and treatment can significantly improve a patient's quality of life, reduce sudden death, and prevent various complications. significantly increased compared to those before surgery, which can significantly improve the symptoms of obstructive sleep apnea syndrome and even achieve complete disappearance of symptoms.

Changes of Adenoid and Pharyngeal Airway Space Following Orthognathic Surgery in Class III Patients with Mandibular Prognathism: A Retrospective Analysis

Aim and Background: This retrospective study evaluated the changes in adenoid and pharyngeal airway spaces associated with surgical mandibular setback in skeletal Class III patients. Patients and Methods: Pre- and one- year-post-operative lateral cephalograms of 25 adult patients with mandibular prognathism who had bilateral sagittal split osteotomy (BSSO) were traced. Cephalometric parameters including SNA, SNB, GoGn to SN, y-axis, SPPS, MPS, IPS, PNS-Eb, at-atp, ppw-Ba were calculated, compared, and then data were analyzed using Paired t-test or Sign test. The role of growth pattern and gender factor was analyzed with Fisher exact test. MannWhitney test was utilized to compare between the groups of male/female as well as the groups of vertical/horizontal grower. The results were considered at a maximum level of significance of 5% (P &lt; 0.05). Results: At long-term follow-up, 25 patients (m:8, f:17) with the mean age of 25±4; there was a decrease in MPS value (3.8±6.7) that statistically significant (P=0.001). Although an increase was found in PNS-Eb index (3.1±4.4), the changes were not significant (P=0.03). No significant change was observed in other parameters. Also, growth pattern and gender didn’t affect the mentioned parameters. Conclusion: Mandibular setback surgery causes a long-term effect in some parameters of pharyngeal airway space area. In patients suffering from obstructive sleep apnea or in case of some other risk factors including overweight, short necks, and small pharyngeal airway space, a mandibular setback surgery could possibly predispose to the development of sleep apnea syndrome.

Investigating the relationship between the remodeling of TMJ bony structures and condylar rest position following orthognathic surgery in class II and class III skeletal malocclusions

ObjectivesWe investigated the bone remodeling in the condyle and glenoid fossa after surgically corrected class II and class III dentoskeletal malocclusion patients and the relationship between these changes and the condylar rest position. MethodsA retrospective study was conducted based on the pre-operative and 1-year postoperative computed tomography (CT) scans of class II and class III skeletal malocclusion patients. Condylar remodeling was assessed by total volume change and surface distance between corresponding points in the regions of interest (ROI). Glenoid fossa remodeling was measured by the surface distance between the closest points in the ROI. The association between the remodeling of TMJ bony structures and the condylar position was tested by Spearman’s correlation. ResultsTwenty-one subjects with class II (17 females, 4 males) and twenty subjects with class III (13 females, 7 males) were recruited.The condylar volumes significantly decreased after surgery in class II malocclusion patients and significantly increased in class III malocclusion patients (p < 0.01). The condyle and glenoid fossa experienced remodeling of less than 1.5 mm and 1 mm respectively. Positional change of condyle at the jaw rest position had a weak correlation with condylar remodeling (p < 0.05, 0.2 ≤ |r| ≤0.4), but no association with the glenoid fossa remodeling (p > 0.05). ConclusionsThe volume of condyles changed significantly after orthognathic surgery in both groups. Both condyle and glenoid fossa experienced remodeling in class II and Class III patients. Those changes did not considerably influence the change of the condylar rest position.

Changes in the condylar head after orthognathic surgery in Class III patients: a retrospective three-dimensional study.

To evaluate the axial and dimensional changes of the condylar head after orthognathic surgery, including Le Fort I and bilateral sagittal split ramus osteotomies, and to assess condylar remodeling through three-dimensional (3D) surface superimposition. Twenty-four patients (15 females, 9 males; mean age: 32.22 ± 6.92 years) with skeletal Class III deformity were included in the study. Cone-beam computed tomography data obtained in the preoperative (T0) and postoperative (T1) periods were examined using Mimics and 3-Matic software. The height, depth, and width of the condylar head and its angular changes were measured. The volumes of the 3D reconstructed models were calculated, and remodeling amounts were evaluated through regional surface superimposition. Statistical significance was set at P < .05. Following the surgery, there was a significant decrease in the size of condyles (P < .05). An inward rotation of the condyles was found in the axial plane (T0: 79.60 ± 6.01°, T1: 76.6 ± 6.48°, P < .05). The maximum resorption, maximum apposition, mean remodeling, and mean absolute remodeling were -2.63 ± 1.23 mm, 1.15 ± 0.4 mm, -0.30 ± 0.34 mm, and 0.73 ± 0.43 mm, respectively. No correlation was found between the angular changes and remodeling parameters or linear and volumetric changes of the condylar head (P > .05). Condyles undergo a remodeling process with a resorptive character following orthognathic surgery, without clinically significant effects in the present study.

Evaluation of the Mandibular Condyle Morphologic Relation before and after Orthognathic Surgery in Class II and III Malocclusion Patients Using Cone Beam Computed Tomography.

Simple SummaryIn individuals with severe malocclusions, orthognathic surgery seeks to rebalance the relationships between the jaws by providing a stable occlusion, a healthy muscle balance, and the functioning of the temporomandibular joint. Cone beam computed tomography may be used to determine the position of the mandibular condyle in the glenoid fossa. This study aimed to assess how the position of the mandibular condyle varies in class II and III malocclusions before and after bimaxillary orthognathic surgery. Before and after orthognathic surgery, 56 TMJs from 28 patients were studied. Following surgery, both class II and class III patients experienced changes in the anterior joint space, posterior joint space, condyle position, and condyle angle. The preliminary findings are promising for determining changes in condyle position and joint spaces that might guide oral and maxillofacial surgeons to address a debilitating clinical affliction.This study aimed at evaluating the mandibular condyle position changes before and after bimaxillary orthognathic surgery in class II and III malocclusion patients. CBCT scans from patients who underwent bimaxillary orthognathic surgery were analyzed: Le Fort I osteotomy and bilateral sagittal split osteotomy (BSSO). Both condyles were independently assessed for their largest anterior and posterior joint spaces, smallest medial joint spaces, and condyle angles concerning the transverse line. In the sagittal plane, the minimum size of the anterior and posterior joint spaces was measured. In the coronal plane, the smallest medial joint space was measured. The position of the condyle within the glenoid fossa was determined before and after surgery. A total of 56 TMJs from 28 patients were studied. Following orthognathic surgery, the anterior and posterior space in class II increased. Postoperatively, the anterior joint space in class III decreased. In 42.85% of malocclusion class II patients and 57.14% of malocclusion class III patients, the pre-and post-surgical position of the condyle changed, the condyle was anteriorly positioned (42.85%) in class II patients and centrically positioned (71.4%) in class III patients. Significant changes in the joint space, condylar position, and condyle angle were found in the class II and class III subjects.

Main clinical approaches to orthognathic surgery for class II open bite and genioplasty patients: a brief systematic review

Introduction: Orthognathic surgery (OS) is used to improve the patient's facial appearance and to correct maxillary and mandibular deformities resulting from malocclusions, disease, or trauma. In this context, genioplasty is a procedure to correct an aesthetic and functional deformity of the chin region, improving the contour. Moreover, anterior open bite (AOB) is the lack of vertical contact or negative overbite between the anterior teeth of the superior and inferior arches when the posterior teeth are in occlusion. Objective: The present study aimed to perform a brief systematic review with risk of bias analysis by funnel plot to highlight the main clinical approaches of orthognathic surgery in class II patients with open bites and also concerning genioplasty. Methods: The research was carried out from February 2022 to May 2022 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 115 articles were found. In total, 57 articles were fully evaluated and 34 were included and evaluated in this study. And of the total of 34 articles, only 11 articles were developed as the main clinical results. A total of 32 articles were excluded because they did not meet the GRADE classification, and 16 were excluded because they were at risk of bias. The symmetric funnel plot does not suggest a risk of bias between the small sample size studies. A retrospective observational study compared 57 patient charts on treatment outcomes for anterior occlusion and vertical skeletal stability after maxillary or mandibular surgery to correct Class II malocclusion with a mild to moderate open bite. After surgery, 87% of Le Fort I patients and 63% of patients with bilateral sagittal split osteotomy had a positive overbite, and at the 6-month follow-up, the percentages were 90% and 74%, respectively. Another study showed Class II patients had significantly greater amounts of lateral and lower translation than class III patients. Also, genioplasty represents one of the most common auxiliary procedures and may be associated with corrective surgery for dentofacial dysmorphisms. However, care must be taken with mental nerve injuries, asymmetries, and intraoperative bleeding are the main immediate complications.

Evaluation of facial soft tissue asymmetric changes in Class III patients after orthognathic surgery using three-dimensional stereophotogrammetry

The aim of this study was to investigate changes in facial soft tissue asymmetry over time after orthognathic surgery in Class III patients using three-dimensional stereophotogrammetry. The study included 101 patients with a skeletal Class III malocclusion (72 female, 29 male; age range 19–53 years, mean age 28.6 years) who underwent orthognathic surgery. The minimum follow-up was 12 months. Three-dimensional photographs were acquired using the 3dMDtrio stereophotogrammetry system, and 21 anthropometric landmark positions were evaluated at three time points: before surgery (T0), 6 months (T1) and 12 months (T2) after surgery. Facial asymmetry was assessed and classified as follows: 0–2 mm, mild; 2–5 mm, moderate;> 5 mm, severe. The average distance for whole face asymmetry differed between T0 (median 0.76 mm) and T1 (median 0.70 mm); however, there was no statistically significant difference at any time point. The chin volume asymmetry score differed significantly between T0 (median 1.11 mm) and T1 and T2 (median 1.08 mm for both; P < 0.001 and P = 0.001, respectively), but not between T1 and T2 (P = 0.061). The study findings indicate that the asymmetry of the facial soft tissues has the potential to return after 6 months, without reaching the baseline.

Comparison of Maximum Bite Force in Class Ш Skeletal Patients Before and After Orthognathic Surgery

Introduction: Orthognathic surgery not only changes the appearance of the face and the occlusion, but also changes the biomechanics and force of chewing. The aim of this study was to evaluate the maximum changes in byte force after orthognathic surgery in class III patients.&#x0D; Materials &amp; Methods: In this clinical trial study, 20 class Ш skeletal patients referred to the School of Dentistry of Isfahan Azad University in the academic year 97-98 were selected and were divided into two groups before orthognathic surgery and 3 months after orthognathic surgery. The surgical technique in these patients was 2-jaw technique (Lefort 1 and BSSO). The area of the first right maxillary molar and the left maxillary first molar were measured at two intervals before surgery and three months after surgery. The sensor was first placed on one side of the first maxillary molar, then on the other side, and vice versa. The measurements were repeated three times on each side and the highest number was recorded as the patient's MBF (Maximum bite force). Data were analyzed using ANOVA and Tukey statistical tests (α = 0.05).&#x0D; Results: Mean maximum dental bite force was significantly decreased 3 months after surgery (p value &lt; 0.001); this did not lead to a significant difference between maximum bite force and gender (p value = 0.244).&#x0D; Conclusion: Maxillofacial surgery in class III skeletal patients reduces the byte force in 3 months after maxillofacial surgery.&#x0D;

Determination of treatment options for Class III malocclusions in adult patients based on cephalometric values: a systematic review

Abstract Objective The present systematic review aimed to determine cephalometric values that may be used as a guide in deciding between orthodontic camouflage and orthognathic surgery to treat a Class III malocclusion in adults. In addition, a secondary aim was to identify treatment complications and aesthetic perceptions by laypersons/orthodontists. Methods Without a language restriction, an electronic search of six databases and a hand search of three orthodontic journals were performed until September 2021. All studies comparing orthodontic camouflage and orthognathic surgery in Class III malocclusion patients, were included. Data extraction was carried out independently by two authors with disagreement resolved by a third author. The risk of bias related to individual studies was appraised using a modified version of the STROBE checklist. The results were summarised qualitatively, and no meta-analysis was undertaken due to the high heterogeneity between the studies. Results With the quality of evidence ranging from moderate to high, six retrospective studies were included. A cephalometric analysis comprising the Holdaway angle, overjet, the Wits appraisal, lower incisor inclination, the maxillary-mandibular ratio, overbite, gonial angle and an additional combination were used as a guide. No treatment complications were reported. One study examined the perception of facial profile attractiveness in borderline surgical Class III malocclusions and found no difference in outcome and significant improvements in both camouflage and surgical groups. Conclusion The existing evidence is insufficient to identify a cephalometric parameter threshold in deciding between orthodontic camouflage and orthognathic surgery. PROSPERO database protocol no. CRD42020165164.

Accuracy of 3 Soft Tissue Prediction Methods After Double-Jaw Orthognathic Surgery in Class III Patients.

We aimed to evaluate the accuracy and validity of conventional manual prediction method (CM) and 2-dimensional and 3-dimensional (3D) soft tissue prediction methods for Class III bimaxillary orthognathic surgery patients. Twenty skeletal Class III patients were included in this study. Soft tissue prediction was achieved with a traditional manual technique, 2-dimensional software (Dolphin Imaging, version 11.5), and 3-dimensional software (SimPlant Master, version 16.0) on preoperative lateral cephalometric radiographs and cone beam computurized tomography (CBCT) images and then compared with postoperative lateral cephalometric radiographs obtained at least 6 months after surgery (mean, 11.5 ± 6.77 months). Forty-eight measurements were done to determine the reliability of the methods. All prediction methods have limited postsurgery prediction accuracy for the subnasal upper lip area. Most of the differences were not more than 3 mm for all study groups, except the 3D software, which predicted the upper lip area to be, on average, 3.08 ± 1.38 mm further back (P < 0.001). Although the conventional method predicted 20 of 48 measurements similar to the final results, the poorest predictions were found at the nasal and labiomental areas (P < 0.001). Two-dimensional software predicted 23 of 48 measurements very close to the final results but made significantly different predictions for the nasolabial and labiomental angles, labrale superius point, and the chin area. The 3D method predicted, especially the upper lip area, to be significantly and clinically incorrect, and its soft tissue prediction was insufficient compared with the other 2 methods. The 3D software needs to be updated, especially in evaluating soft tissue A point and upper lip changes after surgery.

Comparison of Pre-operative and Postoperative Skeletal and Dental Movements in Class III Patients Treated with Conventional and Surgery-first Techniques

The conventional orthognathic-surgery technique involves lengthy pre-surgical orthodontic interventions, while invoking a surgery-first technique eliminates this necessity. Previous studies have reported the degree of skeletal and dental movements achieved using the conventional approach compared to orthodontic camouflage. However, none has directly compared the conventional orthognathic-surgery and surgery-first techniques. The objective of this study was to determine the magnitude of skeletal and dental changes achieved in class III patients with conventional orthognathic surgery (COS) and surgery-first (SF) techniques.In total, 82 lateral cephalograms for class III patients (n = 41) were analyzed for 2 groups: 1) COS (20.9±8.7 years) and 2) SF (20.7±6.6 years). Skeletal parameters such as SNA, SNB, ANB, Wits Analysis, Sn-GoGn, FMA, and lower anterior facial height and dental parameters such as U1-SN, U1-NA (°), U1-NA (mm), L1-NB (°), L1-NB (mm), and overjet were analyzed. Paired T-test analyses were performed to analyze the changes between pre-treatment and post-treatment parameters within the 2 groups, and 2-sample T-tests were used to compare the pre-treatment and post-treatment changes between the 2 groups.COS showed significant increase in L1-GoGn, overjet, ANB, SNA, and Wits analysis. SF showed significant increase in L1-GoGn, L1-NB (°), L1-NB (mm), overjet, ANB, SNA, and Wits analysis and significant decrease in U1-NA (°) and U1-NA (mm). The comparison between COS and SF showed that there was no statistically significant difference in the skeletal and dental parameters between the 2 groups.The results indicate that orthognathic surgery in class III patients with conventional orthognathic-surgery and surgery-first techniques does not produce a difference in results among the skeletal and dental parameters, suggesting that either technique can be used to achieve similar results with a comparable degree of skeletal and dental movement in patients with class III malocclusion.

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

ObjectivesTwo-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 methodsThis 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.ResultsThe 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.ConclusionsAlthough 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 relevanceOne-splint and two-splint surgical techniques produce similar patient-centred outcomes in Class III asymmetry patients.

Orthognathic surgery in class II patients: a longitudinal study on quality of life, TMD, and psychological aspects.

To evaluate, longitudinally, the impacts of orthognathic surgery in patients with skeletal class II malocclusion on oral health-related quality of life (OHRQoL), temporomandibular disorders (TMD) and psychological symptoms. Forty-three patients with skeletal class II malocclusion who were submitted to orthognathic surgery were evaluated during their preoperative and postoperative periods. They answered the short version of the Oral Health Impact Profile (OHIP-14) and were also diagnosed according to Axes I and II of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The evolution of OHRQoL and TMD before and after surgery was verified, and the relationships among these variables were found through statistical analysis using Wilcoxon, McNemar, chi-square, and Mann-Whitney tests, with a 5% significance level. The median of the overall OHIP-14 score and five domains decreased after orthognathic surgery (p< 0.05), the functional limitation domain increased (p= 0.014), and the physical disability domain did not show an association (p= 0.133). There were improvements in articular pain (p= 0.016), chronic pain (p= 0.019), and nonspecific physical symptoms excluding pain (p= 0.013). In addition, an association was found between poorer OHRQoL (overall scale and domains) and the Axis II variables of the RDC/TMD (p< 0.05). Orthognathic surgery improved perceived OHRQoL, articular pain, and chronic pain. The conditions of Axis II of the RDC/TMD interfered with OHRQoL postoperatively. Although orthognathic surgery improves QoL and some TMD conditions in skeletal class II patients, poorer postoperative outcomes are observed when psychological conditions are present.

The relationship between bimaxillary orthognathic surgery and the extent of posterior airway space in class II and III patients – A retrospective three-dimensional cohort analysis

ObjectiveTo assess the relationship between bimaxillary orthognathic surgery in class II and III patients, the three-dimensional extent of the posterior airway space (PAS) using cone-beam computed tomography (CBCT). MethodsA retrospective evaluation of a cohort of Class II and III patients, who had undergone orthognathic surgery (Le Fort I osteotomy, bilateral sagittal split osteotomy), between December 2011 and July 2014, was performed. In each case, CBCT scans were performed one week prior (T1) to and 6 months (T2) after surgery, followed by analysis of several airway parameters (volume, mean cross-sectional area, and diameter) and the three-dimensional extent of mandibular movement. ResultsIn Class II patients significant postoperative volumetric increases in the middle and lower PAS segment as well as in all diametric and spherical variables (p ≤ 0.001) could be seen. In Class III patients there were only significant postoperative increases in the volumetric, and partially in diametric and spherical, variables (p < 0.05) of the upper PAS segment. There was also a significant linear relation between forward displacement of the maxilla and mandible and some airway parameters (p < 0.05). ConclusionsThese results reveal that bignathic surgery in Class II patients provokes an increase in most dimensions of the PAS. This intervention can be assumed to reduce airway resistance and might therefore be a suitable treatment option for patients suffering from OSAS. For bignathic surgery in Class III patients, a positive effect could be seen, especially at the nasopharynx.

Effects on the upper airways with orthognathic surgery in class II patients

Effects on the upper airways with orthognathic surgery in class II patients