Facial Asymmetry Caused by Mandibular Condylar Hyperplasia: A Two Center Study.

BACKGROUND: Condylar hyperplasia is a non-neoplastic overgrowth of the mandibular condyle. The disorder is progressive and causes gradual jaw deviation, facial asymmetry, and dental malocclusion. The only treatment capable of stopping hyperplastic growth is surgical condylectomy to remove the upper portion of the condyle containing the deranged growth center. When this procedure is conducted in proportion to the length of the healthy side it may also correct the jaw deviation and facial asymmetry. OBJECTIVES: To assess the degree to which condylectomy corrects the asymmetry and to determine the proportion of patients after condylectomy who were satisfied with the esthetic result and did not desire further corrective surgery. METHODS: We conducted a retrospective analysis of medical records of patients who underwent condylectomy that was not followed by corrective orthognathic surgery for at least 1 year to determine the degree of correction of chin deviation and lip cant. Patient satisfaction from treatment or desire and undergo further corrective surgery was reported. RESULTS: Chin deviation decreased after condylectomy from a mean of 4.8° to a mean of 1.8° (P < 0.001). Lip cant decreased after condylectomy from a mean of 3.5° to a mean of 1.5° (P < 0.001). Most patients (72%) were satisfied with the results and did not consider further corrective orthognathic surgery. CONCLUSIONS: Proportional condylectomy could be a viable treatment to both arrest the condylar overgrowth and achieve some correction of the facial asymmetry.

Abordagem cirúrgica em fratura de sínfise e côndilo mandibular bilateral em paciente pediátrico: um relato de caso / Surgical approach for syphysis and bilateral mandibular condyle fracture in a pediatric patient: a case report

As indicações de tratamento das fraturas mandibulares em paciente pediátrico variam em conservador, fixação não rígida e interna rígida. Alterações no crescimento ósseo, disfunções na articulação temporomandibular e assimetrias faciais podem ser decorrentes ao insucesso do tratamento. O objetivo deste trabalho consiste em relatar abordagem cirúrgica em fratura de sínfise e côndilo mandibular bilateral em paciente pediátrico. Paciente gênero feminino, 09 anos de idade, foi encaminhada ao Hospital Geral do Estado - Bahia vítima de queda de nível, cursando com trauma em face. Apresentou queixa principal, referida pela progenitora, de dificuldades em fechar a boca. Ao exame físico, a paciente apresentou mobilidade atípica à manipulação da mandíbula, mordida aberta anterior, equimose sublingual, ausência das unidades dentárias 74 e 75, com abertura bucal regular e suturas em posição em região de mento. Ao exame de imagem de tomografia computadorizada da face, pôde-se notar sinais sugestivos de fratura em região de sínfise e côndilos mandibulares bilateral. Após diagnóstico das fraturas, a paciente foi submetida à cirurgia sob anestesia geral para redução e fixação das mesmas. Realizou-se acessos em ferimento na região mentual e retromandibular bilateral com posterior síntese das fraturas utilizando fixação interna rígida com placas do sistema 2.0mm, associada a odontossíntese na fratura de sínfise. Ao acompanhamento periódico, a eleição do tratamento cirúrgico para fraturas mandibulares em pacientes pediátricos, pode permitir segurança no crescimento ósseo mandibular e facial(AU)

The indications for treatment of mandibular fractures in pediatric patients vary from conservative, non-rigid fixation and rigid internal fixation. Changes in bone growth, temporomandibular joint disorders and facial asymmetries may be due to treatment failure. The objective of this work is to report a surgical approach to bilateral symphysis and mandibular condyle fractures in a pediatric patient. Female patient, 9 years old, was sent to the State General Hospital - Bahia, victim of a fall in level, suffering from trauma to the face. She presented a main complaint, mentioned by her mother, of difficulties in closing her mouth. On physical examination, the patient presented atypical mobility when manipulating the jaw, anterior open bite, sublingual ecchymosis, absence of dental units 74 and 75, with regular mouth opening and sutures in position in the chin region. When examining the computed tomography image of the face, signs suggestive of fracture in the region of the symphysis and bilateral mandibular condyles were noted. After diagnosis of the fractures, the patient underwent surgery under general anesthesia to reduce and fix them. Access was performed on a wound in the mental and bilateral retromandibular region with subsequent synthesis of the fractures using rigid internal fixation with 2.0mm system plates, associated with odontosynthesis in the symphysis fracture. With periodic monitoring, the choice of surgical treatment for mandibular fractures in pediatric patients can allow for safe mandibular and facial bone growth(AU)

Mandibular condyle volumes are associated with facial asymmetry in patients with cleft lip and palate: A retrospective cohort study.

This study compares condylar volumetric asymmetry and facial asymmetry in patients with cleft lip and/or palate (CLP) and controls. The mandibular condyle is important to facial growth, but its role in facial asymmetry for those with CLP has not been described. Condylar volumes and mandibular asymmetry were retrospectively calculated using Mimics Version 23.0 (Materialise, Leuven, Belgium) from patients with CLP undergoing computed tomography (CT) imaging and a cohort of controls. A total of 101 participants, 60 with CLP and 41 controls, had mean condylar volumetric asymmetry of 16.4 ± 17.4 % (CLP) and 6.0 ± 4.0 % (controls) (p = 0.0002). Patients with CLP who had clinically significant chin deviation (>4 mm) had more asymmetric condyles than those without significant chin deviation (p = 0.003). The chin deviated toward the smaller condyle in patients with facial asymmetry more often than in patients without facial asymmetry (81 % vs. 62 %, p = 0.033). While controls had some degree of condylar asymmetry, it tended to be milder and not associated with facial asymmetry. There is a greater degree of condylar volumetric asymmetry in patients with CLP compared to individuals in the general population. Clinically significant facial asymmetry in CLP is associated with a higher degree of condylar asymmetry, with the facial midline deviating toward the smaller condyle.

[Mandibular condyle localization in orthognathic surgery based on mandibular movement trajectory and its preliminary accuracy verification].

OBJECTIVE: To establish and assess the precision of pre-surgical condyle position planning using mandibular movement trajectory data for orthognathic surgery. METHODS: Skull data from large-field cone beam computed tomography (CBCT) and dental oral scan data were imported into IVSPlan 1.0.25 software for 3D reconstruction and fusion, creating 3D models of the maxilla and mandible. Trajectory data of mandibular movement were collected using a mandibular motion recorder, and the data were integrated with the jaw models within the software. Subsequently, three-dimensional trajectories of the condyle were obtained through matrix transformations, rendering them visually accessible. A senior oral and maxillofacial surgeon with experience in both diagnosis and treatment of temporomandibular joint disease and orthognathic surgery selected the appropriate condyle position using the condyle movement trajectory interface. During surgical design, the mobile mandibular proximal segment was positioned accordingly. Routine orthognathic surgical planning was completed by determining the location of the mandibular distal segment, which was based on occlusal relationships with maxilla and facial aesthetics. A virtual mandible model was created by integrating data from the proximal and distal segment bone. Subsequently, a solid model was generated through rapid prototyping. The titanium plate was pre-shaped on the mandibular model, and the screw hole positions were determined to design a condylar positioning guide device. In accordance with the surgical plan, orthognathic surgery was performed, involving mandibular bilateral sagittal split ramus osteotomy (SSRO). The distal segment of the mandible was correctly aligned intermaxillary, while the proximal bone segment was positioned using the condylar positioning guide device and the pre-shaped titanium plate. The accuracy of this procedure was assessed in a study involving 10 patients with skeletal class Ⅱ malocclusion. Preoperative condyle location planning and intraoperative positioning were executed using the aforementioned techniques. CBCT data were collected both before the surgery and 2 weeks after the procedure, and the root mean square (RMS) distance between the preope-rative design position and the actual postoperative condyle position was analyzed. RESULTS: The RMS of the condyle surface distance measured was (1.59±0.36) mm (95%CI: 1.35-1.70 mm). This value was found to be significantly less than 2 mm threshold recommended by the expert consensus (P < 0.05). CONCLUSION: The mandibular trajectory may play a guiding role in determining the position of the mandibular proximal segment including the condyle in the orthognathic surgery. Through the use of a condylar positioning guide device and pre-shaped titanium plates, the condyle positioning can be personalized and customized with clinically acceptable accuracy.

[Comparison of the virtual surgical planning position of maxilla and condyle with the postoperative real position in patients with mandibular protrusion].

OBJECTIVE: To compare the difference between virtual surgical planning (VSP) position and postoperative real position of maxilla and condyle, and to explore the degree of intraoperative realization of VSP after orthognathic surgery. METHODS: In this study, 36 patients with mandibular protrusion deformity from January 2022 to December 2022 were included. All the patients had been done bilateral sagittal split ramus osteotomy (SSRO) combined with Le Fort Ⅰ osteotomy under guidance of VSP. The VSP data (T0) and 1-week postoperative CT (T1) were collected, the 3D model of postoperative CT was established and segmented into upper and lower jaws in CCMF Plan software. At the same time, accor-ding to the morphology of palatal folds, the virtual design was registered with the postoperative model, and the unclear maxillary dentition in the postoperative model was replaced. Then the postoperative model was matched with VSP model by registration of upper skull anatomy that was not affected by the operation. The three-dimensional reference plane and coordinate system were established. Selecting anatomical landmarks and their connections of condyle and maxilla for the measurement, we compared the coordinate changes of marker points in three directions, and the angle changes between the line connecting the marker points and the reference plane to analyze the positional deviation and the angle deviation of the postoperative condyle and maxilla compared to VSP. RESULTS: The postoperative real position of the maxilla deviates from the VSP by nearly 1 mm in the horizontal and vertical directions, and the anteroposterior deviation was about 1.5 mm. In addition, most patients had a certain degree of counterclockwise rotation of the maxilla after surgery. Most of the bilateral condyle moved forward, outward and downward (the average distance deviation was 0.15 mm, 1.54 mm, 2.19 mm, respectively), and rotated forward, outward and upward (the average degree deviation was 4.32°, 1.02°, 0.86°, respectively) compared with the VSP. CONCLUSION: VSP can be mostly achieved by assistance of 3D printed occlusal plates, but there are certain deviations in the postoperative real position of maxilla and condyle compared with VSP, which may be related to the rotation axis of the mandible in the VSP. It is necessary to use patient personalized condylar rotation axis for VSP, and apply condylar positioning device to further improve surgical accuracy.

Comparison of disc position stability and condylar bone remodelling between two open disc repositioning surgeries: a retrospective single-centre cohort study.

BACKGROUND AND OBJECTIVE: Open suturing (OSu) and mini-screw anchor (MsA) are two commonly used open disc repositioning surgeries for anterior disc displacement (ADD) of the temporomandibular joint (TMJ). This study assesses the differences in disc position stability (DPS) and condylar bone remodelling (CBR) between these two surgical procedures in a single centre. METHODS: A retrospective cohort study using MRI scans (pre-operation, 1 week and 12 months post-operation) of all patients who had open TMJ disc repositioning surgery from January 2016 to June 2021 at one centre through two surgical techniques (OSu and MsA) was performed. The predictor variable was technique (OSu and MsA). Outcome variables were DPS and CBR. During follow-up, DPS was rated as good, acceptable and poor, and CBR was graded as improved, unchanged, and degenerated. Multivariate analysis was used to compare the DPS and CBR at 12 months after adjusting five factors including age, sex, Wilkes stage, preoperative bone status (normal, mild/moderate abnormal) and the degree of disc repositioning (normal, overcorrected, and posteriorly repositioned). Relative risk (RR) for DPS and CBR was calculated by multivariate logistic regression. RESULTS: Three hundred eighty-five patients with 583 joints were included in the study. MRIs at 12 months showed that 514 joints (93.5%) had good DPS, and 344 joints (62.5%) had improved CBR. Multivariate analysis revealed that OSu had higher DPS (RR=2.95; 95% CI, 1.27-6.85) and better CBR (RR=1.58; 95% CI, 1.02-2.46) than MsA. Among the factors affecting DPS, females had better results than males (RR=2.63; 95% CI, 1.11-6.26) and overcorrected or posteriorly repositioned discs were more stable than normally repositioned discs (RR=5.84; 95% CI, 2.58-13.20). The improvement in CBR decreased with age increasing (RR=0.91; 95% CI, 0.89-0.93). Preoperative mild/moderate abnormal bone status had a higher probability of improved CBR compared to normal preoperative bone status (RR=2.60; 95% CI, 1.76-3.83). CONCLUSION: OSu had better DPS and CBR than MsA. Sex and the degree of disc repositioning impacted DPS, while age and preoperative bone status affected CBR.

Accuracy and stability of the condyle position after orthognathic surgery: A retrospective study.

The purpose of this study was to evaluate the accuracy and stability of condylar positioning in patients treated with bimaxillary procedures compared with patients treated with maxillary procedures alone. All patients had undergone treatment at Odense University Hospital and were treated with inferior maxillary procedures. The primary outcome was changes in condyle position and the primary predictor variable was time: pre-operative (T0) measurements to 1-week post-operative (T1) and 1-year post-operative (T2) measurements. Condyle movement was measured using dual voxel-based alignment. Sixteen patients were included. Seven patients underwent solitary maxillary procedure and 9 patients bimaxillary procedure. Bimaxillary procedures overall showed a condyle positional change in pitch from T0 to T1 and T1 to T2 compared to maxillary procedures alone. Condylar translation was stable despite large differences in positioning. Compared to solitary maxillary procedures, bimaxillary procedures showed a statistically significant anterocranial rotation at 1-week follow-up movement (3.95° vs. -0.95°; SD 3,74 vs 1,05; P value = 0.000) and an additional statistically significant anterocranial movement at 1 year after surgery (4.89° vs 0.60°; SD 3,82 vs 0,92; P value = 0.000). In conclusion a need for greater anterocranial stability of the sagittal split osteotomy than that provided by 3 bicortically fixated screws alone might be indicated.

A proposed protocol for correlation between bone density in hemimandibular hyperplasia radiography and histopathological findings - A retrospective study.

The role of low-dose computed tomography (LDCT) in surgical planning can be assessed based on the correlation among bone density (BD/HU), radiographic values, and the histopathological appearance of hyperplastic overgrowth in mandibular condyles (hemimandibular hyperplasia/osteochondroma). The aim of this study was to evaluate the correlation between LDCT indices of bone-density measurements in surgical planning and histopathological specimens. The patients incuded in this study underwent detailed radiological evaluation as preparation for further clinical procedures. Excised condyles were evaluated in terms of bone density index using LDCT, and then histopathologically to investigate the accuracy of surgical procedures and set the basis for future surgical planning. An index value between both condyles' bone densities represented the relative difference between the healthy condyle and the side with hemimandibular hyperplasia (HH). Patients with unilateral condylar hyperplasia (UCH) showed a statistical correlation between condyle heads with increased bone density (BD) and scintigraphic (SCI) values (p < 0.001). On the other hand, correlation between BD and histopathological studies alone was significant (p < 0.001). With the increase in BD measured in HU in UCH condyles, the overall value of fibrous cartilage layer thickness decreased (p < 0.001). Furthermore, histopathological evaluation indicated that increased bone density on the UCH side resulted in increased total thickness (p > 0.001). The proposed index measurements in the mandibular condyles based on LDCT/BD can be used to estimate the degree of required surgical resection. Results from LDCT radiographic studies correlate with histopathological specimens more than scintigraphy.

Suggestion of a new standard in measuring the mandible via MRI and an overview of reference values in young women.

PURPOSE: Adult idiopathic condylar resorption (AICR) mainly affects young women, but generally accepted diagnostic standards are lacking. Patients often need temporomandibular joint (TMJ) surgery, and often jaw anatomy is assessed by CT as well as MRI to observe both bone and soft tissue. This study aims to establish reference values for mandible dimensions in women from MRI only and correlate them to, e.g., laboratory parameters and lifestyle, to explore new putative parameters relevant in AICR. MRI-derived reference values could reduce preoperative effort by allowing physicians to rely on only the MRI without additional CT scan. METHODS: We analyzed MRI data from a previous study (LIFE-Adult-Study, Leipzig, Germany) of 158 female participants aged 15-40 years (as AICR typically affects young women). The MR images were segmented, and standardized measuring of the mandibles was established. We correlated morphological features of the mandible with a large variety of other parameters documented in the LIFE-Adult study. RESULTS: We established new reference values for mandible morphology in MRI, which are consistent with previous CT-based studies. Our results allow assessment of both mandible and soft tissue without radiation exposure. Correlations with BMI, lifestyle, or laboratory parameters could not be observed. Of note, correlation between SNB angle, a parameter often used for AICR assessment, and condylar volume, was also not observed, opening up the question if these parameters behave differently in AICR patients. CONCLUSION: These efforts constitute a first step towards establishing MRI as a viable method for condylar resorption assessment.

Effect of arthroscopic discopexy on condylar growth in adolescents with temporomandibular joint disc displacement without reduction: A retrospective self-controlled case series study.

This study was a retrospective self-controlled study that aimed to evaluate the effect of arthroscopic discopexy on condylar height and mandibular position in adolescents with temporomandibular joint (TMJ) anterior disc displacement without reduction (ADDwoR). Patients between 10 and 20 years of age and diagnosed with bilateral TMJ ADDwoR by magnetic resonance image (MRI) were included in this study. All patients underwent a period of natural course before arthroscopic surgery and then a follow-up period postoperatively. Changes in condylar height and mandibular position were measured by MRI and X-ray radiographs. Data were analyzed by paired t-test, Pearson correlation analysis, and generalized estimating equations. This study comprised a total of 40 patients with a mean age of 14.80 years. Pearson correlation analysis showed correlations between condylar height and mandibular position changes. The condylar height change during the post-operative period was significantly higher than that during natural course period (3.57 mm, p < 0.001). The changes in mandibular position (including ANB angle, SNB angle, and Pog-Np) were significant different (all p < 0.05) between the two periods. This study found that arthroscopic discopexy can promote condylar growth and correct dentofacial deformity in adolescents with bilateral TMJ ADDwoR.

A Temporary Intraoperative Fixation Method for the Absorbable Plates Fixation of Condylar Fracture by Retromandibular Transparotid Approach.

The authors describe a temporary intraoperative fixation method for the absorbable plates' fixation of subcondylar fracture by retromandibular transparotid approach. First, the fracture was temporarily fixed with a 4-hole titanium microplate across the fracture line in the center of the lateral surface of the condyle to maintain the reduction of the fracture. Then, two 4-hole absorbable mini-plates were fixed on the posterior and anterior border of the condylar neck. Finally, the 4-hole titanium microplate and screws were removed before the wound closure. In the absorbable plates' fixation of subcondylar fracture by transparotid approach, the method of temporary intraoperative fixation using a 4-hole titanium microplate offsets the limited exposure of the operative field, smooths the operation, and offers the reliability and validity of the absorbable plates' fixation.

Imaging features of temporomandibular joint synovial chondromatosis with associated osseous degenerative changes.

Synovial chondromatosis (SC) of the temporomandibular joint (TMJ) is a rare benign disease associated with the formation of multiple cartilaginous nodules in the synovial tissue of the TMJ. This can result in pain, swelling, clicking, limited mouth opening, and osseous degenerative joint changes. A retrospective cross-sectional study was performed to summarize the clinical features, radiographic findings, and surgical and histopathological findings of TMJ SC patients who underwent open surgery over a 24-year period. A radiographic scoring system was used to evaluate osseous changes and correlate condyle and joint fossa degeneration. The study included 38 patients and focused on 38 joints. All 38 of these joints showed degenerative changes in the condyle, while 37 showed osseous degenerative changes in the articular fossa. The degree of condylar degenerative changes was related to the duration of the chief complaints (r = 0.342, P = 0.036) and the histopathological stage of the TMJ SC (r = 0.440, P = 0.006), while the degree of joint fossa degenerative changes was associated with the radiographic extent of the SC (r = 0.504, P = 0.001), type of calcification (r = 0.365, P = 0.024), and the histopathological stage (r = 0.458, P = 0.004).

Can dynamic elastic therapy be established as the standard protocol of closed reduction for moderately displaced extracapsular condylar fractures?

OBJECTIVE: This study was conducted with the aim to establish standard technique of closed reduction (CR) and compare functional outcomes in patients of moderately displaced unilateral extracapsular condylar fractures. MATERIAL AND METHODS: This study is a retrospective randomized controlled trial, conducted at a tertiary care hospital setting from August, 2013 to November, 2018. Patients of unilateral extracapsular condylar fractures with ramus shortening < 7mm and deviation < 35° were divided in two groups by drawing lots and were treated by dynamic elastic therapy and maxillomandibular fixation (MMF). Mean and standard deviation were calculated for quantitative variables, and one way analysis of variance (ANOVA) and Pearson's Chi-square test were used to determine significance of outcomes between two modalities of CR. P value < 0.05 was taken as significant. RESULTS: The numbers of patients treated by dynamic elastic therapy and MMF were 76 (38 in each group). Out of which 48 (63.15%) were male and 28 (36.84%) were female. The ratio of male to female was 1.7:1. The mean ± standard deviation (SD) of age was 32 ± 9.57 years. In patients treated by dynamic elastic therapy, the mean ± SD (at 6-month follow-up) of loss of ramus height (LRH), maximum incisal opening (MIO) and opening deviation were 4.6mm ± 1.08mm, 40.4mm ± 1.57mm and 1.1mm ± 0.87mm respectively. Whereas, LRH, MIO and opening deviation were 4.6mm ± 0.85mm, 40.4mm ± 2.37mm and 0.8mm ± 0.63mm respectively by MMF therapy. One-way ANOVA was statistically insignificant (P value > 0.05) for above mentioned outcomes. Pre-traumatic occlusion was achieved in 89.47% of patients by MMF and in 86.84% patients by dynamic elastic therapy. Pearson's Chi-square test was statistically insignificant (p value < 0.05) for occlusion. CONCLUSION: Parallel results were obtained for both modalities; thus, the technique as dynamic elastic therapy, which promotes early mobilization and functional rehabilitation, can be favored as standard technique of closed reduction for moderately displaced extracapsular condylar fractures. This technique eases patients' stress associated with MMF and prevents ankylosis.

Evaluation of joint kinematics in patients with condylar reconstruction using mandibular motion simulation based on intraoral scanning registration.

AIM: To summarize the features of condylar kinematics in patients with condylar reconstruction using a mandibular motion simulation method based on intraoral scanning registration. MATERIALS AND METHODS: Patients undergoing unilateral segmental mandibulectomy and autogenous bone reconstruction as well as healthy volunteers were enrolled in the study. Patients were grouped based on whether the condyles were reconstructed. Mandibular movements were recorded using a jaw tracking system, and kinematic models were simulated after registration. The path inclination of the condyle point, margin of border movement, deviation, and chewing cycle were analyzed. A t test and one-way analysis of variance (ANOVA) were carried out. RESULTS: A total of 20 patients, including 6 with condylar reconstruction and 14 with condylar preservation as well as 10 healthy volunteers were included. The patients with condylar reconstruction showed flatter movement paths of the condyle points. The mean inclination angle of the condylar movement paths of the patients with condylar reconstruction (0.57 ± 12.54 degrees) was significantly smaller than that of those with condylar preservation (24.70 ± 3.90 degrees, P = 0.014) during both maximum opening and protrusion (7.04 ± 12.21 degrees and 31.12 ± 6.79 degrees, respectively, P = 0.022). The inclination angle of the condylar movement paths of the healthy volunteers was 16.81 ± 3.97 degrees during maximum opening and 21.54 ± 2.80 degrees during protrusion; no significant difference compared with the patients. The condyles of the affected side tended to deviate laterally in all patients during mouth opening and protrusion. Patients with condylar reconstruction showed more severe symptoms of mouth opening limitation and mandibular movement deviation as well as shorter chewing cycles than patients with condylar preservation. CONCLUSION: Patients with condylar reconstruction showed flatter movement paths of the condyle points, greater lateral motion range, and shorter chewing cycles than those with condylar preservation. The method of mandibular motion simulation based on intraoral scanning registration was feasible to simulate condylar movement.

Intraoperative ultrasonography for the reposition of the condylar process during bilateral sagittal osteotomy of the mandible-A case report.

INTRODUCTION: Ultrasonography (USG), being a safe, quick and relatively cheap examination, is used to diagnose various pathologic conditions. The application of ultrasound to assess the position of the condyle during bilateral sagittal split osteotomy (BSSO) may improve the treatment results. CASE PRESENTATION: A 33-year-old patient, who was operated for a skeletal defect of maxilla and mandible with BSSO and Le Fort I maxillary osteotomy is discussed in this case report. The procedure was complicated with a mandibular head dislocation. The split segment was repositioned under ultrasound guidance, and a repeat osteosynthesis was performed. CONCLUSIONS: The ultrasound method is useful for the intraoperative assessment of the condylar process' position. The use of ultrasound in the diagnosis of complications and for intraoperative monitoring should be promoted.

Mandibular condylar fractures: a 5-year retrospective analysis comparing open versus closed reduction.

BACKGROUND: Mandibular fractures are common facial fractures, and contemporary management of mandibular condylar fractures is controversial. The purpose of this study was to compare the outcomes of patients who sustained a mandibular condylar fracture between 2016 and 2020, who were managed by either open or closed techniques. The outcomes of this study were: post-operative facial nerve function, occlusion, and maximal mouth opening. METHODS: This study is a retrospective multicentre cohort study which assessed clinical records for 246 patients with mandibular condyle fractures in three hospitals in Perth, Western Australia. The primary outcome measure was changes in post-operative facial nerve function. RESULTS: One hundred and thirty-two patients underwent open reduction and internal fixation (ORIF), and 114 patients had closed management. The overall rate of temporary facial nerve injury following ORIF was 3.28%. The overall rate of permanent facial nerve injury was 0.82%. Sialocoele occurred in 2.46% of all patients who underwent ORIF. 6.14% of patients had persisting malocclusion across both groups. There was a statistically significant association between the degree of fragment shortening and facial nerve injury (P = 0.0063), with more facial nerve changes in the group with 5 mm or greater of fragment shortening. CONCLUSIONS: There is still significant debate over the management of mandibular condylar injuries. This study demonstrates a similar rate of temporary and permanent facial nerve injury as previously described, as well as a similar rate of sialocoele occurrence. Further prospective studies may provide clarity about important characteristics that will help guide decision making for mandibular condylar fractures.

Three-dimensional bone remodelling of glenoid fossa in patients with skeletal Class III malocclusion after bimaxillary orthognathic surgery.

This study aimed to characterize three-dimensional quantitative morphological changes of glenoid fossa in patients with skeletal Class III malocclusion treated with bimaxillary orthognathic surgery. Ninety-five eligible patients (50 male, 45 female; mean age 22.09 years) were enrolled retrospectively. Cone beam computed tomography obtained at 1 week preoperatively (T0), immediately after surgery (T1), and at ≥ 12 months postoperatively (T2) were registered based on cranial base using voxel-based registration in 3D Slicer. Glenoid fossa surface was divided spatially into four regions, and bone modelling in these regions was visualized with color maps. Our data revealed that the mean surface variations of glenoid fossa were small, with modest bone formation as a whole. No significant associations between anteroposterior or vertical mandibular displacement and overall glenoid fossa remodeling were found (P > 0.05). Moreover, bone deposition was frequently observed in the anterior-lateral region of glenoid fossa in patients with a larger mandibular movement during T0-T1 (P < 0.001). Paired bone formation in the anterior-lateral region of glenoid fossa and bone resorption in the anterior-lateral region of condylar head was frequently observed. Collectively, our results revealed that glenoid fossa underwent complex but modest bone remodeling after bimaxillary surgery in skeletal Class III patients.

The Role of Digital Surgical Planning and Surgical Guides in the Treatment of Unilateral Condylar Hyperplasia.

Unilateral condylar hyperplasia (UCH) results in facial asymmetry, malocclusion, and temporomandibular joint dysfunction. Treatment consists of both surgical and orthodontic intervention. A review was performed for 4 patients with UCH who underwent digital surgical planning (DSP)-assisted condylectomy. All patients were female, aged 14 to 35 years at the time of operation with facial asymmetry and class III malocclusion. None of the patients had prior treatment and all had perioperative orthodontic appliances to provide fixation and postoperative elastic therapy. All patients underwent DSP-guided condylectomy, and intraoperative surgical cutting guides were used for 3 of the patients. All had significant improvement in facial symmetry and occlusion. None had recurrence, and additional intervention has not been required. If UCH is recognized before marked secondary changes in the maxilla, mandible, and occlusion, future orthognathic surgery may be potentially obviated. Craniomaxillofacial surgeons should consider using DSP and surgical guides in the treatment of UCH.

Accuracy of computer-assisted design and manufactured three-dimensional device for condylar positioning in mandibular bilateral sagittal split osteotomy (clinical trial).

INTRODUCTION: Aligning dental arches in orthognathic treatment after undergoing LeFort I osteotomy or bilateral sagittal split osteotomy (BSSO) relies on occlusal splints, which do not provide precise control over the condylar head. AIM OF THE STUDY: To clinically and radiographically assess the accuracy of computer-assisted design and manufactured (CAD/CAM) surgical guide for condylar positioning in a BSSO. MATERIALS AND METHODS: The study recruited 8 patients with a non-syndromic dentofacial deformity who underwent a BSSO. Surgery was planned according to CAD/CAM technology. After osteotomy, a pre-operative guide was used, followed by a repositioning guide. Computed tomography scans were conducted on all patients 1 week pre-operatively, immediately, and 3 months postoperatively. RESULTS: The data are presented as median values with the 25th and 75th percentiles. Eight patients (37.50% females and 62.50% males) between the ages of 19 and 24 underwent BSSOs. The surgical procedure successfully corrected their skeletal deformities. The absolute change between immediate postoperative and pre-operative condylar angle was 0.15 (0.00-0.3). The absolute change between 3 months postoperative and pre-operative condylar angle was 0.20 (0.00-0.30). CONCLUSION: The stability of the condylar head in position is well assessed by 3-dimensional condylar positioning devices designed and manufactured by CAD/CAM technology in the mandibular BSSO.