Site and severity of facial asymmetry after bimaxillary surgery for class III deformity: a case-control study.

OBJECTIVES: The study aimed (1) to evaluate the site and severity of facial asymmetry in Class III patients before and after bimaxillary surgery, and (2) to identify the influence of initial severity and positional jaw asymmetry on residual facial asymmetry. MATERIALS AND METHODS: Preoperative and postoperative cone-beam computed tomography of 65 patients with Class III facial asymmetry who underwent bimaxillary surgery were evaluated. Five midline and 14 paramedian facial soft tissue landmarks were identified to assess facial asymmetry. The outcomes were compared to a control group consisting of 30 age- and gender-matched Class I subjects. The postoperative positional jaw asymmetry (i.e., shift, roll, yaw) of each osteotomy segment (maxilla, mandible, chin, ramus) was also measured. RESULTS: Before surgery, the asymmetry was more severe at the chin, middle and lower contour. Bimaxillary surgery effectively corrected facial asymmetry, particularly in achieving normalization of chin deviation. However, significant asymmetry persisted postoperatively in the middle and lower contour (p < 0.001 and p < 0.01, respectively), which was affected by the positional ramus asymmetry in the roll and shift. CONCLUSIONS: Deviation of the chin, middle and lower contour contributed significantly to overall facial asymmetry in Class III asymmetry. Despite normalization of the chin deviation after bimaxillary surgery, asymmetry persisted at the middle and lower contour, primarily as the result of insufficient correction of the positional ramus asymmetry. CLINICAL RELEVANCE: Understanding the residual asymmetry after bimaxillary surgery is important for minimizing deviation and optimizing the surgical planning for its correction.

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.

Assessment of Masseter Volume and Postoperative Stability After Orthognathic Surgery in Patients With Skeletal Class III Malocclusion With Facial Asymmetry.

OBJECTIVE: This study aimed to evaluate the effect of orthognathic surgery on masseter volume in patients with skeletal Class III malocclusion with facial asymmetry and the effect of masseter volume on stability in orthognathic surgery. METHODS: This research studied 16 patients with Class III malocclusion with facial asymmetry who received combined orthodontic-orthognathic treatment and underwent craniofacial computed tomography (CT) before (T0), 2 weeks after (T1), and 6 months after (T2) surgery. Three-dimensional (3D) CT images were retrospectively analyzed, using 3D volume reconstruction to obtain the masseter volume and examine the impact of the masseter volume on stability in orthognathic surgery. RESULTS: A statistically significant difference ( P < 0.05) in the volume of the masseter was found up to 6 months after orthognathic surgery compared with the preoperative period, and the reduction in the masticatory muscle volume on the lengthened side is greater than on the shortened side ( P < 0.05). The volume of both masseters differed according to facial asymmetry, and the difference was significantly reduced after orthognathic surgery ( P < 0.05). During the period time (T1-T2), cephalometric maxillary marker points were not significantly different ( P > 0.05), and mandibular marker points were significantly anteriorly shifted ( P < 0.05). There was an association between the masseter volume and anterior shift of point B (R > 0.5, P < 0.05), the upward and anterior shifts of the gonion point differed between the lengthened and shortened sides ( P < 0.05). CONCLUSION: The size of the masseter becomes smaller 6 months after orthognathic surgery, and orthognathic surgery improves both bone and soft tissue symmetry. A larger sagittal relapse of mandibular setback occurred in patients with greater masseter volume. Considering these alterations may be helpful in planning orthognathic surgery.

The Evaluation of Condylar Position Change in the Asymmetric Mandible Following Sagittal Split Osteotomy.

BACKGROUND: The change of condyle position following orthognathic surgery affects the stability of treatments. This study aims to assess the correlation between the amount of condyles' position change and the severity of mandibular asymmetry following BSSO. MATERIALS AND METHODS: This is a cross-sectional study. Subjects with asymmetric mandibular prognathism following BSSO were studied. Subjects were classified into 2 groups: group 1, subjects had mandibular asymmetry without occlusal cant and underwent BSSO. Group 2, subjects had mandibular asymmetry with occlusal cant and underwent BSSO+ Lefort I osteotomy. The condyle position was evaluated using cone-beam computer tomography (CBCT). Pearson's correlation test was used to assess any correlation between the condyle changes and the change in the mandible in sagittal and anterior-posterior directions. RESULTS: A total of 44 subjects were studied. In group 1, the condyle tilted outward in the deviated condyle and inward in the non-deviated condyle immediately after osteotomy. After 12 months, both condyles showed a rotation relative to the original position. In group 2, the condyles of the deviated sides and non-deviated sides moved inferiorly after surgery (condylar sagging), which was more significant in the non-deviated sides. The condyle rotation was similar to group 1. The severity of asymmetry and occlusal cant correlate with the condylar position change in the two groups. CONCLUSION: The severity of mandibular asymmetry correlates with the amount of condyles' position change immediately after BSSO. However, the condyles tend to return to their original position 12 months later.

Changes in masseter muscle morphology after surgical-orthodontic treatment in patients with skeletal Class III malocclusion with mandibular asymmetry: The automatic masseter muscle segmentation model.

INTRODUCTION: This study evaluated the masseter muscle changes after surgical-orthodontic treatment in patients with a skeletal Class III malocclusion using automatic segmentation. METHODS: Images of 120 patients with skeletal Class III malocclusion were obtained and reconstructed at T0 (pretreatment), T1 (presurgery), and T2 (6-12-month postsurgery). The patients were divided into symmetrical and asymmetrical groups. The volume, major axis length, maximum cross-sectional area, horizontal cross-sectional area 5 mm above the mandibular foramen (CSAF), and orientation were calculated automatically. RESULTS: In the asymmetrical group, the volume and major axis length on the deviated side were lower than on the nondeviated side at T0, T1, and T2 (P <0.05). There were no significant differences in maximum cross-sectional area and CSAF bilaterally. The orientation was coronally more vertical and sagittally more forward on the deviated side (both P <0.001). In the symmetrical group, there were no significant bilateral differences at T0, T1, and T2. The volume, major axis length, and CSAF decreased, and the coronal orientation was more vertical on the nondeviated side at T2 than at T0 in both groups (P <0.05). The coronal plane orientation was more inclined on the deviated side at T2 than at T0 in the asymmetrical group (P <0.05). CONCLUSIONS: The smaller volume on the deviated side at T2 indicates the need for myofunctional training after surgery. The masseter muscle volume and the cross-sectional area did not recover to the preorthodontic levels. Studies with longer follow-up durations are needed to confirm these findings.

Symmetry recovery in zygomaticomaxillary complex fractures compared to normal unfractured population: A new reliable 3D evaluation.

OBJECTIVE: This study aims to quantify the facial symmetry of surgically treated zygomaticomaxillary complex (ZMC) fractures through a new reliable three-dimensional evaluation method, which is crucial for improving post-operative aesthetic and functional outcomes. MATERIAL AND METHODS: Healthy patients and patients with surgically treated ZMC fractures were retrospectively reviewed. Using Brainlab Elements® the zygomatic bone and the orbit of each patient was segmented and mirrored. Subsequently, the mirrored side was matched with the other side via volume-based registration, using the segmented orbit as reference. Volumetric asymmetry was measured using 3-matic software, and a surface-based matching technique was used to calculate the mean absolute differences (MAD) between the surfaces of the two sides of the ZMC. The reliability of this novel method using volume-based registration was tested, and the intra-class correlation coefficient was assessed. RESULTS: The MAD between the surfaces of the left and right sides in the control group was 0.51 mm (±0.09). As for the ZMC fracture group, MAD was 0.78 mm (±0.20) and 0.72 mm (±0.15) pre- and post-operatively, respectively. The MAD showed statistically significant differences between pre- and post-operative groups (p = 0.005) and between control and post-operative groups (p < 0.001). The intra-class correlation coefficient was high (≥0.99). CONCLUSIONS: This evaluation method using mirroring and volume-based registration to determine the symmetrical position of the ZMC is reliable. The surface-based measurements revealed an improved symmetry after surgery. However, the symmetry of the treated patients remained lower than the control group.

Mandibular Distraction Osteogenesis in Children and Adolescents: A Clinical and Radiographic Research Using Cone-Beam Computed Tomography.

AIM: The aim of this cross-sectional study was to evaluate, via cone-beam computed tomography, the long-term postoperative outcome in children treated with mandibular distraction osteogenesis. MATERIALS AND METHODS: All young patients treated with mandibular distraction osteogenesis (MDO), during a 16-year period, at the University Department of Oral and Maxillofacial Surgery of a Pediatric Hospital, were recalled, and various clinical and radiographic parameters were recorded. RESULTS: Eleven patients were included: 5 with hemifacial microsomia (HFM) and 6 with mandibular micrognathia. In all cases, MDO had been successful in regular follow-up and decannulation, soon after MDO, was achieved in all tracheostomy cases. The long-term result in cases of HFM was found stable, functionally and esthetically accepted, although less satisfactory than in regular follow-up; in micrognathia patients, relapse of different degrees was registered in 4 of 6 cases, without any need for tracheostomy though. Detailed and accurate information was obtained by cone-beam computed tomography (CBCT). The shape of the regenerated bone was irregular in HFM cases and relatively normal in the micrognathia cases. Quality of the regenerated bone was normal in all patients. The irregular shape registered in HFM cases did not compromise a safe orthognathic operation. CONCLUSIONS: Distraction osteogenesis remains an early treatment choice in cases of mandibular deformities. Long-term findings showed that there is a degree of relapse with growth, which was more obvious in mandibular micrognathia cases. Computed tomography contributes to detailed evaluation of changes at the distraction site.

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.

Combining Patient-specific Implant With Malar Reduction to Repair Mid-facial Asymmetry Caused by Craniofacial Fractures in Asians.

Mid-facial asymmetry caused by bone defect or deformation resulted from craniofacial fracture was a common secondary complication needed to repair. Patient-specific implant (PSI) designed with the unaffected side as a template is a good choice to repair this kind of facial asymmetry. However, in Asians, the broad and prominent zygomatic bone in unaffected side is not an optimal template, because the oval facial shape was considered as a more attractive appearance in Asian esthetic concept. To repair the mid-facial asymmetry and to improve the facial contour, the authors combined PSI implantation with malar reduction in one-stage surgery. The authors referred the facial proportion index (the optimal ratio of mid and lower face was 1.27) as a basis for preoperative precise design to determine the ideal facial shape of unaffected side, and used mirror image overlay technique with the ideal shape of unaffected side as a template to design the PSI. With this surgical strategy, patients not only can repair facial asymmetry but also can get a more attractive appearance.

Intraoral volume changes in relation to the hard tissue shape changes in asymmetric patients before and after orthognathic surgery - A retrospective CT study.

OBJECTIVES: To evaluate Intraoral volume changes in relation to the hard tissue shape changes in asymmetric patients before and after orthognathic surgery and establish a correlation between them. MATERIALS AND METHODS: A retrospective study which evaluated 12 asymmetric patients' pre and post-surgical CT records satisfying the inclusion criteria. Borders were defined for the measurement of extraoral, intraoral and tongue volume. The volume assessment was carried out using software from 3D SYSTEMS, Colorado, US, Version 1.0.2.2055. RESULTS: Predicting changes in volume between extra-oral, intra-oral spaces and tongue, Linear regression modeling of the data revealed that for every mm3 change in post-surgical extra-oral volume the post-surgical intra-oral volume decreased by 0.684 mm3 and for every mm3 change in post-surgical intra-oral volume, the post-surgical tongue volume increased by 0.728 mm3. CONCLUSIONS: Significant decrease in the extra-oral volume, Intra-oral volume and tongue volume was evident after orthognathic surgery in patients with facial asymmetry. This volumetric approach sheds insight into achieving a muscular equilibrium between intraoral and extraoral structures, which would improve orofacial function and enhance facial aesthetics.

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.

Complications in patients with facial bone fractures before and after conservative and surgical treatment, their comparison and correlation with different factors.

OBJECTIVE: This study aims to determine the occurrence of complications before and after the treatment of facial fractures, as well as the impact of the factors on the treatment results and evaluation of their relationships. PATIENTS AND METHODS: This is a prospective case-control study comprising 90 patients aged between 18 and 65 with facial fractures. Depending on the treatment method, patients were divided into three groups: those treated surgically using a transcutaneous approach, those treated surgically using a transmucosal approach, and those treated conservatively (control group). Following complications before and after treatment were compared: malocclusions, paresthesias, facial asymmetry, diplopia, and limited mouth opening. The follow-up period after the treatment of choice was six months. RESULTS: There was a significant reduction in complications after treatment: malocclusion, paresthesia, facial asymmetry, and limited mouth opening. Regarding the transcutaneous approach, there is a substantial reduction in the number of complications after treatment, such as malocclusions (p=0.008), paresthesias (p=0.004), and facial asymmetries (p<0.001). Similar results were obtained for the transmucosal approach. Pain intensity positively correlated with preoperative complications: malocclusion, paresthesias, and facial asymmetry. The range of mouth opening had a negative interdependence with malocclusion before and after treatment with infection, fractura male sanata, malocclusion, paresthesias, postoperative level of mouth opening, and damage to the facial nerve. CONCLUSIONS: There is no difference in the reduction of preoperative and postoperative complications related to surgery when an incision is made through the skin or mucosa. Malocclusions, paresthesias, and facial asymmetry are reduced through surgical methods.

Anatomical Conditions in Simultaneous Orthognathic Surgery and Structural Rhinoplasty. A Clinical Series / Condiciones Anatómicas en Cirugía Ortognática y Rinoplastia Estructural Simultanea. Una Seria Clínica

SUMMARY: Orthognathic surgery and rhinoplasty show synergy in terms of function and aesthetic results. The aim of this research is to analyze variables related to simultaneous orthognathic surgery and rhinoplasty and to discuss the surgical sequence. Male and female subjects between 18 and 45 years old were included in this research. Diagnosis related to nasal morphology (nasal tip bifid, rotate, square and others as well as the alae morphology and columella), facial deformity (sagittal and vertical deformity), type of surgery (rhinoplasty techniques and orthognathic techniques) and complications were included. The minimum follow-up was 12 months; Chi- Square and t test were used to define correlations, considering a value of p<0.05 for statistical significance. Class III facial deformity was observed in 40 % of subjects and class II facial deformity was present in 43 %. For the nasal deformities, the tip and nasal bridge were most prevalent; primary nasal deformity was observed in the 83 % of subjects and was significant more than secondary nasal deformity (p=0.042). Bimaxillary surgery was performed in 31 cases (88 %). In 10 cases a change of the original plan for rhinoplasty due to previous maxillary surgery was realized, mainly in class III facial deformity, with no statistical differences. Revision rhinoplasty was realized in 5 cases (14 %) and was not related to surgical variables; revision for orthognathic surgery was not necessary in this series. Rhinoplasty and orthognathic surgery simultaneously show low complications and predictable results. We can conclude that maxillary mandibular osteotomies and rhinoplasty could be performed safely. However, larger studies are necessary to understand the best choice and variables involved in simultaneous procedures and soft tissue response.

La cirugía ortognática y la rinoplastia muestran sinergia en términos de resultados funcionales y estéticos. EL objetivo de esta investigación es analizar variables relacionadas con la cirugía ortognática y rinoplastia ejecutada de forma simultanea. Fueron incluidos hombres y mujeres entre 18 y 45 años de edad. EL diagnóstico fue en base a la morfología nasal (punta bífida, rotada, cuadrada u otras así como alteraciones del ala nasal y columela), deformidad facial (deformidad sagital y vertical), tipo de cirugía (técnica de rinoplastia y cirugía ortognática) y complicaciones asociadas. El seguimiento mínimo fue de 12 meses; se utilizo las prueba t test y chi cuadrado para definir relaciones estadísticas considerando un valor de p< 0,05 para obtener diferencias significativas. La deformidad clase III fue observada en el 40 % de los sujetos y la deformidad facial de clase II se presento en el 43 %. Para la deformidad nasal, las alteraciones de a punta nasal y nasal fueron mas prevalentes; la deformidad nasal primaria se presentó en el 83 % de los sujetos y fue significativamente mayor que la deformidad nasal secundaria (p=0,042). La cirugía bimaxilar se realizó en 31 casos (88 %); en 10 casos se realizó el cambio del plan quirúrgico inicial de la rinoplastia debido a cambios generados en la cirugía maxilar previa, mayormente en deformidad facial de clase III, sin presentar diferencias significativas. La rinoplastia de revisión fue realizada en 5 casos (14 %) y no fue relacionada con ninguna variable de tipo quirúrgica; la revisión de cirugía ortognática no fue realizada en ningún caso de esta serie. La rinoplastia y la cirugía ortognática simultanea mostraron bajas complicaciones y resultados predecibles. Se puede concluir que la osteotomía maxilo mandibular y la rinoplastia son seguras; sin embargo, estudios de mayor volumen son necesarios para entender la mejor opción y variables relacionadas con procedimientos simultáneos y la respuesta de tejidos blandos faciales.

Three-dimensional evaluation of symmetry in facial palsy reanimation using stereophotogrammetric devices: A series of 15 cases.

Facial palsy can severely compromise quality of life, significantly altering the harmony and symmetry of the face, which can be restored by surgical rehabilitation. The aim of the study was the quantification of facial symmetry following facial reanimation. Fifteen consecutive adult patients were surgically treated through triple innervation for reanimation of flaccid unilateral facial paralysis (contralateral facial nerve, masseteric nerve, and hypoglossal nerve) and fascia lata graft for definition of the nasolabial sulcus. In the preoperative stage and at least 11 months after the surgical treatment, three-dimensional facial images were recorded through stereophotogrammetry in a neutral (rest) position, and with Mona Lisa and full-denture (maximum) smiles. Labial commissure inclination relative to the interpupillary axis, and a surface assessment of local facial asymmetry at rest and while smiling were obtained for the upper, middle, and lower facial thirds. The angle between the interpupillary axis and the labial commissure significantly improved in post-surgical acquisitions, regaining symmetry at rest (t-test; p < 0.001). Facial symmetry increased significantly when passing from pre-to postsurgical facial scans, from the lower to the upper facial third, and from the full smile to the rest position (ANOVA; p < 0.001). After treatment, the full smile recovered more symmetry than the other two expressions. In summary, surgical treatment significantly reduced facial asymmetry, but this reduction differed significantly among the various animations and facial thirds. The results of this study confirmed clinical findings of significant static and dynamic improvements in facial symmetry after triple innervation reanimation surgery.

[Model test study on treatment of Pruzansky type â ¡B and â ¢ hemifacial microsomia with artificial condyle-mandibular distractor complex].

Objective: To preliminarily verify the effectiveness of self-designed artificial condyle-mandibular distraction (AC-MD) complex in the treatment of Pruzansky type ⅡB and Ⅲ hemifacial microsomia (HFM) through model test. Methods: Five children with Pruzansky type ⅡB and Ⅲ HFM who were treated with mandibular distraction osteogenesis (MDO) between December 2016 and December 2021 were selected as the subjects. There were 3 boys and 2 girls wih an average age of 8.4 years (range, 6-10 years). Virtual surgery and model test of AC-MD complex were performed according to preoperative skull CT of children. The model was obtained by three-dimensional (3D) printing according to the children's CT data at a ratio of 1∶1. The occlusal guide plate was designed and 3D printed according to the children's toothpaste model. The results of the model test and the virtual surgery were matched in three dimensions to calculate the error of the residual condyle on the affected side, and the model test was matched with the actual skull CT after MDO to measure and compare the inclination rotation of the mandible, the distance between the condylar of the healthy side and the residual condyle of the affected side, and the lengthening length of the mandible. Results: The error of residual condyle was (1.07±0.78) mm. The inclination rotation of the mandible, the distance between the condylar of the healthy side and the residual condyle of the affected side, and the lengthening length of the mandible after 3D printing model test were significantly larger than those after MDO ( P<0.05). Conclusion: In the model test, the implantation of AC-MD complex can immediately rotate the mandible to the horizontal position and improve facial symmetry, and the residual condyle segment can be guided close to the articular fossa or the preset pseudoarticular position of the skull base after operation.

Risk factors for postoperative infection after bilateral sagittal split ramus osteotomy: A retrospective analysis.

BACKGROUND: This retrospective clinical study investigated risk factors for infection following bilateral sagittal split ramus osteotomy (BSSO) as orthognathic surgery, including the patients' general condition, local factors, and surgical factors. PATIENTS AND METHODS: The cases of 160 mandibular sites of 80 Japanese patients (26 males, 54 females; mean ± SD age: 25.3 ± 7.7 years, range 16-55 yrs) with a jaw deformity who underwent BSSO orthognathic surgery at our Department of Oral and Maxillofacial Surgery between Jan. 2017 and Dec. 2022 were analyzed. Potential risk factors were classified as clinical predictive variables. Descriptive and univariate statistics were computed. A multivariate analysis was performed with logistic regression. RESULTS: Fifteen mandibular sites (9.4 %) were complicated with postoperative infection. The multivariate analysis revealed significant differences in facial asymmetry (OR 24.0, p = 0.0002) and the amount of mandibular movement (OR 0.664, p = 0.011) between the sites with and without infection. CONCLUSIONS: Among clinical variables, facial asymmetry was the strongest risk factor for post-BSSO infection, followed by the amount of mandibular movement.

Single photon emission computed tomography (SPECT) diagnostic accuracy in active unilateral condylar hyperplasia: Retrospective study.

The aim of this study was to assess the diagnostic accuracy of single photon emission tomography (SPECT) in unilateral condylar hyperplasia (UCH). To this end, 3D morphometric changes of the mandibles in one year were assessed (T0 vs. T1) and compared over SPECT results in T1, in a sample of 40 patients. A contingency table was constructed based on these results for SPECT diagnostic accuracy evaluation, classifying patients as SPECT true-positive, true-negatives, false positives and false-negatives. Additionally, the morphometric analysis was used to describe the presentation of mandibular changes using principal component analysis (PCA) and non-parametric statistics. We obtained diagnostic accuracy results of sensitivity 81%, specificity 63%, positive predictor value (PPV) 59%, negative predictor value (NPV) 83% and accuracy 70%, showing that SPECT yields poor results regarding accuracy diagnostic performance. The morphometric analysis showed that individuals without progress of asymmetry and those with more progress differ particularly in a group of landmarks representing the mental region and the right mandibular body. Based on these landmarks, difference among the four SPECT-accuracy groups was statistically significant (p < 0.001), where the landmark showing the largest change within a year had a mean increase of 1.13 + 0.66 mm. Within the limitations of the study, it seems that SPECT alone is not suitable for making surgical decisions regarding condylectomy in active UCH. Follow up with morphological assessment methods are recommended for confirming an active UCH in combination with SPECT.

An innovative analysis of nasolabial dynamics of surgically managed adult patients with unilateral cleft lip and palate using 3D facial motion capture.

AIM: To compare dynamic nasolabial movement between end-of-treatment cleft and a matched non-cleft group in adult patients. MATERIALS AND METHODS: Thirteen treated adult participants with unilateral cleft lip and palate had images taken using a facial motion capture system performing a maximum smile. Seventeen landmarks were automatically tracked. For each landmark pair, on either side of the midline, changes in the x, y, and z directions were used to analyze the magnitude of displacement and path of motion. An asymmetry score was developed at rest, mid-smile, and maximum smile to assess the shape of the mouth and/or nose. RESULTS: At maximum smile, displacement of right and left cheilion was clinically and statistically (p < 0.05) less in the cleft group. The lip asymmetry score was greater (p < 0.05) at each time point in the cleft group using the clinical midline. Using Procrustes superimposition, the differences were significant (p < 0.05) only at rest and mid-smile. The alar bases were displaced significantly less (p < 0.05) in the z direction in the cleft group. The asymmetry score of the alar base was significantly higher using the clinical midline than using Procrustes superimposition in patients with cleft conditions (p < 0.001). In the cleft group, at maximum smile, the right and left cristae philter moved significantly less (p < 0.05) in the x and z directions. CONCLUSIONS: There was an increase in asymmetry score of the corners of the mouth and alar bases from rest to maximum smile. The lips were similar in shape but oriented differently in the faces of patients with cleft conditions than in individuals without those conditions.