Deformity Research Articles

Simulating the Morphological Changes of Facial Deformities after Using 3D-printed Polyether Ether Ketone Facial Implants.

Patient-specific implants (PSIs) have been presented as an effective solution for diseases that require reconstruction. PSIs are designed to precisely fit anatomical defects or deformities in terms of shape and size. In addition to the possibility of predicting the results of surgery regarding soft tissue changes. A research sample consisting of 10 patients with facial deformities underwent maxillofacial reconstructive surgery between 2020 and 2021 in the Tishreen University Hospital, Syria. All patients underwent computed tomography scans; then, the design of the required facial implant was carried out, and the three-dimensional soft tissues were reconstructed using the ExoCad 3.0 program based on the computed tomography. The final form of the facial implant was printed from polyether ether ketone, and then surgical work was performed. The patients were followed up after 6 months. Then, a comparison was made between the virtual design and the real result. The absolute difference between the expected soft tissue changes result and the actual result did not exceed three-tenths for all patients, and only two of 10 patients had measurements higher than 20%. This technique can be relied upon with the placement of implants to predict the outcome of the surgical procedure in terms of morphological changes in the facial soft tissues covering PSI polyether ether ketone. Therefore, it is possible to make a virtual design based on the cosmetic requirements of the patient.

A Review of Surgical Incisions Used for the Excision of Benign Parotid Tumors.

To provide surgical references for selecting appropriate parotidectomy incisions, reviewing modified approaches, incision designs, and associated complications. We have systematically searched 5 medical literature databases examining parotidectomy incision designs and postoperative complications from 2008 to 2021. There are a total of 9 novel incision designs: 1) posterior auricular hairline incision (PAHI); 2) combined preauricular and retroauricular incision (CPRI); 3) V-shaped incision (VI); 4) N-shaped incision (NI); 5) postaural incision (PI); 6) preauricular crutch incision (PCI); and 7) endaural incision (EI). Simultaneously, there are a total of 8 postoperative complications: 1) infection; 2) salivary fistula; 3) facial nerve palsy/paresis; 4) ear lobule numbness; 5) Frey syndrome; 6) facial deformity; 7) hematoma; and 8) tumor reoccurrence. Over the last decade, a surge in modified parotidectomy incisions has been witnessed in clinical practice. This expansion is attributed to rapid technical advancements and a deeper understanding of anatomy and histopathology. These modified approaches contribute significantly to improving cosmetic outcomes, minimizing associated complications, and enhancing patient satisfaction.

Quality of Life After Orthognathic Surgery in Swedish Patients: A Register-Based Cohort.

This study aimed to evaluate the effect of orthognathic surgery on quality of life among Swedish patients. Patients subjected to orthognathic surgery due to dentofacial deformity (DFD) and registered in the National Register of Orthognathic Surgery (NROK) in Sweden between 2017 and 2020 were eligible for inclusion in this study. The Swedish-validated Orthognathic Quality of Life Questionnaire (S-OQLQ) was used to evaluate patient quality of life before and after surgery. The S-OQLQ measured each patient's subjective experience regarding social aspects. Eighty-four participants were included in this cohort study, including 45 men (mean age 24.7 years), 48 women (mean age 23.4 years), and eight patients who stated no gender. Women generally graded several aspects of the S-OQLQ higher than men, including facial aesthetics p = 0.029), oral function (p < 0.001), and awareness of facial deformity (p = 0.0054). For all domains of the questionnaire (social, facial aesthetics, function, and awareness), a significant improvement was seen 6-24 months after surgery (p < 0.001). Women rated improvement of function and awareness of facial deformity higher than men (p < 0.001 and p = 0.039, respectively). Quality of life aspects of orthognathic surgery have a strong impact on the treatment outcome. Although functional impairment is often considered a major indication for surgery, the social and aesthetic influence of DFD is highly rated by patients, whereas pain is not an issue before or after treatment.

Facial feature point detection under large range of face deformations

Facial Feature Point Detection (FFPD) plays a significant role in several face analysis tasks such as feature extraction and classification. This paper presents a Fully Automatic FFPD system using the application of Random Forest Regression Voting in a Constrained Local Model (RFRV-CLM) framework. A global detector is used to find the approximate positions of the facial region and eye centers. A sequence of local RFRV-CLMs are used to locate a detailed set of points around the facial features. Both global and local models use Random Forest Regression to vote for optimal positions. The system is evaluated in the task of facial expression localization using five different facial expression databases of different characteristics including age, intensity, 6-basic expressions, 22 compound expressions, static and dynamic images, and deliberate and spontaneous expressions. Quantitative results of the evaluation of automatic point localization against manual points (ground truth) demonstrated that the results of the proposed approach are encouraging and outperform the results of alternative techniques tested on the same databases.

COMPARATIVE ASSESSMENT OF BONE FIXATION METHODS IN CRANIOFACIAL SURGERIES: A systematic review

Bone fixation plays a crucial role in craniofacial surgeries, being essential for the correction of cranial and facial deformities, as well as for stabilization after trauma or reconstructive surgery. This article presents a systematic review of the different bone fixation methods used in craniofacial surgeries, including plates and screws, rigid internal fixation, external fixation and biological techniques. The aim is to compare the efficacy, safety and clinical outcomes of these methods, providing valuable insights to guide clinical practice.

EVALUATION OF THE USE OF DENTAL IMPLANTS IN PATIENTS WITH FACIAL DEFORMITIES

The use of implants as a material to restore function and aesthetics is commonly mentioned in clinical routine, however, little is addressed about the management of this same material in patients with facial deformities, whether resulting from syndromic profiles, congenital or acquired abnormalities. The current literature review presents, in a qualitative way, rehabilitative studies in patients with different aspects of facial deformities, carried out between 2014 and 2023, using exclusively the use of implants as rehabilitative material, either as the only proposed treatment or in a multidisciplinary way, bringing into focus the problem faced by patients and professionals involved with the respective clinical mentions.

Orofacial Harmonization versus Facial Deformities: A Literature Review

In the current context, orofacial harmonization can serve as a complementary means to treat deformities, whether from an aesthetic or functional perspective. In this scope, the present study aims to evaluate the use of hyaluronic acid fillers and botulinum toxin in correcting facial defects. This study consists of a literature review based on the determination of the theme, using the databases PubMed, EBSCO, SciELO, and Google Scholar. The temporal delimitation was established from 2018 to the present. The MeSH descriptors used in the research were: "hyaluronic acid filler," "facial abnormalities," and "augmentation," adding respective descriptors for each topic (ocular, nasal, ear, and lip palate oral). Data were collected between March and April 2023. A final sample of eight articles was obtained, based on the inclusion criteria adopted, with the highest number of publications identified in 2021 (n=3; 37.5%). All the results were in English, predominantly from the PubMed and Google Scholar databases. Regarding the type of facial deformity, it was observed that cleft lip and palate and chin deformity were the majority of the studies analyzed. In terms of the type of orofacial harmonization approach, hyaluronic acid injection was the most used method. Therefore, it was concluded that orofacial harmonization can assist in the rehabilitation of patients with some facial deformity, whether congenital or acquired, thus being a viable treatment option for patients with facial deformities.

Research on ballistic properties of UHMWPE hybrid laminates impregnated with shear thickening fluid

In this paper, a technology of impregnating ultra-high molecular weight polyethylene (UHMWPE) with shear thickening fluid (STF) was proposed to prepare composite laminates, and the ballistic properties of laminates with hybrid configurations were studied. Firstly, two kinds of STFs were prepared using silica particles of 20 nm and 500 nm. Then, STF-impregnated UHMWPE composite laminates were prepared using the hot-press lamination process. Finally, a ballistic experimental study of different combinations of laminates was carried out using a two-stage light gas gun. The results of the study show that the energy absorption rate of the hybridized laminate with the 20 nm + 50 nm configuration scheme is enhanced by more than 9.3 % compared to the laminate impregnated with the single STF. The laminate’s back face deformation depth (BFD depth) after impregnation with shear thickening fluid is only 66.8 % of that of pure UHMWPE laminate. The research work can provide new ideas and references for designing and developing new protective equipment.

A Real-Time and Privacy-Preserving Facial Expression Recognition System Using an AI-Powered Microcontroller

This study proposes an edge computing-based facial expression recognition system that is low cost, low power, and privacy preserving. It utilizes a minimally obtrusive cap-based system designed for the continuous and real-time monitoring of a user’s facial expressions. The proposed method focuses on detecting facial skin deformations accompanying changes in facial expressions. A multi-zone time-of-flight (ToF) depth sensor VL53L5CX, featuring an 8 × 8 depth image, is integrated into the front brim of the cap to measure the distance between the sensor and the user’s facial skin surface. The distance values corresponding to seven universal facial expressions (neutral, happy, disgust, anger, surprise, fear, and sad) are transmitted to a low-power STM32F476 microcontroller (MCU) as an edge device for data preprocessing and facial expression classification tasks utilizing an on-device pre-trained deep learning model. Performance evaluation of the system is conducted through experiments utilizing data collected from 20 subjects. Four deep learning algorithms, including Convolutional Neural Networks (CNN), Recurrent Neural Networks (RNN), Long Short-Term Memory (LSTM) networks, and Deep Neural Networks (DNN), are assessed. These algorithms demonstrate high accuracy, with CNN yielding the best result, achieving an accuracy of 89.20% at a frame rate of 15 frames per second (fps) and a maximum latency of 2 ms.

Hemifacial Spasm Associated With the Specific Offending Vein.

Hemifacial spasm (HFS) caused by venous compression is a rare occurrence. Currently, there is no relevant research on the venous characteristics and potential pathogenic mechanisms causing venous HFS. Exploring the venous characteristics in venous-type HFS may reduce the likelihood of repeated surgery. The authors presented 4 cases of HFS caused by veins of middle cerebellar peduncle (V. of Mid.Cer.Ped) successfully treated with microvascular decompression. Based on intraoperative observations and abnormal muscle response (AMR) monitoring, it was determined that V. of Mid.Cer.Ped were offending vessels in these patients. Moreover, veins crossed between the facial and vestibulocochlear nerves, and then surrounded the ventral aspect of the facial nerve root. Microvascular decompression for the offending vessel was successfully performed, and AMR disappeared for each patient. These patients were discharged without any complications and involuntary contractions or twitching of facial muscles. The study demonstrated that veins can indeed induce HFS. The characteristic of the V. of Mid.Cer.Ped that leads to HFS is that these veins traverse between the facial nerve and the vestibulocochlear nerve, and then surround the ventral aspect of the facial nerve root. The dynamic influence of cerebrospinal fluid leads to pulsatile impingement of the facial nerve on the vein, resulting in facial nerve bending and deformation at the location of the vein. Significantly, in the context of surgery, if it is noticed that the V. of Mid.Cer.Ped surrounds the ventral aspect of the facial nerve root and the facial nerve is compressed and deformed, when AMR disappears after decompression of the artery, it may be necessary to perform vein decompression.

Comparative study of cemento-ossifying fibroma and focal cemento-osseous dysplasia in the jaw – 15 year retrospective inquiry and literature review

BackgroundCemento-ossifying fibroma (COF) and focal cemento-osseous dysplasia (FCOD) are benign neoplasms occurring in the mandible and maxilla; histologically, they both show normal bone replacement by a fibrous stroma containing variable amounts of calcified fragments resembling bone and cementum. FCOD is relatively common and requires observation; COF is rare and its growth over time can lead to deformity in the head and neck region. Surgical removal of COF at an early stage is critical to prevent recurrence and deformity. Therefore, distinguishing COF from FCOD is important for proper further management. Methods and MaterialsTo determine the parameters differentiating COF from FCOD, we retrospectively analyzed 15 COF cases and 27 FCOD cases reviewed between 2005 and 2020 at Temple University Hospital. Demographic, radiographic and histopathologic characteristics were compared by using Student’s t test for continuous variables and Chi-square test for categorical variables. ResultsIn the non-histopathologic spectrum, COF occurred at a younger age (average age-31yo versus FCOD 43 yo). FCOD showed female predilection compared with COF. No significant difference was observed regarding location and radiographic density. However, COF was significantly associated with radiographic cortical expansion. In the histopathologic spectrum, FCOD was more frequently associated with significant intralesional hemorrhage, increased vascularity, osteoblastic rimming of trabeculae, and ginger roots –like bone trabeculae. DiscussionWe demonstrated 7 clinical, radiographic, and pathologic parameters that can help differentiate COF from FCOD. Comprehensive assessment of the distinguishing characteristics is valuable for accurate diagnosis and treatment of these two entities, aiding in minimizing unnecessary procedures for FCOD and averting facial deformities caused by COF.

Large Language Models Diagnose Facial Deformity.

This study examines the application of Large Language Models (LLMs) in diagnosing jaw deformities, aiming to overcome the limitations of various diagnostic methods by harnessing the advanced capabilities of LLMs for enhanced data interpretation. The goal is to provide tools that simplify complex data analysis and make diagnostic processes more accessible and intuitive for clinical practitioners. An experiment involving patients with jaw deformities was conducted, where cephalometric measurements (SNB Angle, Facial Angle, Mandibular Unit Length) were converted into text for LLM analysis. Multiple LLMs, including LLAMA-2 variants, GPT models, and the Gemini-Pro model, were evaluated against various methods (Threshold-based, Machine Learning Models) using balanced accuracy and F1-score. Our research demonstrates that larger LLMs efficiently adapt to diagnostic tasks, showing rapid performance saturation with minimal training examples and reducing ambiguous classification, which highlights their robust in-context learning abilities. The conversion of complex cephalometric measurements into intuitive text formats not only broadens the accessibility of the information but also enhances the interpretability, providing clinicians with clear and actionable insights. Integrating LLMs into the diagnosis of jaw deformities marks a significant advancement in making diagnostic processes more accessible and reducing reliance on specialized training. These models serve as valuable auxiliary tools, offering clear, understandable outputs that facilitate easier decision-making for clinicians, particularly those with less experience or in settings with limited access to specialized expertise. Future refinements and adaptations to include more comprehensive and medically specific datasets are expected to enhance the precision and utility of LLMs, potentially transforming the landscape of medical diagnostics.

Mandibular Contouring in Subjects With Class II or Class III Dentofacial Deformities and Treatment Needs

Facial contouring relates to hard and soft structures that make up the face. Skeletal class II and III subjects present bone structure and position changes, significantly impacting the soft tissues. This study aims to analyze the morphology of the mandible at mandibular ramus and angle level in subjects with skeletal facial deformity class II and III who are candidates for orthognathic surgery and to define implications in facial contour. A cross-sectional study used cone beam computed tomography to compare the mandibular contour (mandibular angle and ramus region) in orthognathic surgery candidates. One hundred sixty orthognathic surgery candidates were analyzed, ranging in age from 18 to 58 years (31.29 ± 11.97). Regarding the skeletal class, 95 (59.37%) were skeletal class II, and 65 (40.62%) were skeletal class III. Class II subjects had a larger antegonial notch than class III subjects. Concerning the mandibular contour, class II subjects presented less vertical distance than class III subjects, but both presented similar gonial angles. Concerning the ideas to assess the need for mandibular contouring surgery, the 2 proposals to determine the need for mandibular contouring surgery in class II and III subjects present a similar distribution. The mandibular notch is an objective element and is commonly present in subjects with a class II facial pattern; this element can be used in contour analysis to define expected facial characteristics, including the patient’s facial sex, in the decision of surgical techniques for lower facial contour augmentation or reduction.

Appearance-Preserved Portrait-to-Anime Translation via Proxy-Guided Domain Adaptation.

Converting a human portrait to anime style is a desirable but challenging problem. Existing methods fail to resolve this problem due to the large inherent gap between two domains that cannot be overcome by a simple direct mapping. For this reason, these methods struggle to preserve the appearance features in the original photo. In this article, we discover an intermediate domain, the coser portrait (portraits of humans costuming as anime characters), that helps bridge this gap. It alleviates the learning ambiguity and loosens the mapping difficulty in a progressive manner. Specifically, we start from learning the mapping between coser and anime portraits, and present a proxy-guided domain adaptation learning scheme with three progressive adaptation stages to shift the initial model to the human portrait domain. In this way, our model can generate visually pleasant anime portraits with well-preserved appearances given the human portrait. Our model adopts a disentangled design by breaking down the translation problem into two specific subtasks of face deformation and portrait stylization. This further elevates the generation quality. Extensive experimental results show that our model can achieve visually compelling translation with better appearance preservation and perform favorably against the existing methods both qualitatively and quantitatively. Our code and datasets are available at https://github.com/NeverGiveU/PDA-Translation.

Engineering a targeted and safe bone anabolic gene therapy to treat osteoporosis in alveolar bone loss

Alveolar bone loss in elderly populations is highly prevalent and increases the risk of tooth loss, gum disease susceptibility, and facial deformity. Unfortunately, there are very limited treatment options available. Here, we developed a bone-targeted gene therapy that reverses alveolar bone loss in patients with osteoporosis by targeting the adaptor protein Schnurri-3 (SHN3). SHN3 is a promising therapeutic target for alveolar bone regeneration, because SHN3 expression is elevated in human and mouse mandible tissues with osteoporosis while deletion of SHN3 in mice greatly increases alveolar bone and tooth dentin mass. We used a bone-targeted recombinant adeno-associated virus (rAAV) carrying an artificial microRNA (miRNA) that silences SHN3 expression to restore alveolar bone loss in mouse models of both postmenopausal and senile osteoporosis by enhancing WNT signaling and osteoblast function. Additionally, rAAV-mediated silencing of SHN3 enhanced bone formation and collagen production of human skeletal organoids in xenograft mice. Finally, rAAV expression in the mandible was tightly controlled via liver- and heart-specific miRNA-mediated repression or via a vibration-inducible mechanism. Collectively, our results demonstrate that AAV-based bone anabolic gene therapy is a promising strategy to treat alveolar bone loss in osteoporosis.

Artificial Intelligence Used for Diagnosis in Facial Deformities: A Systematic Review.

AI is included in a lot of different systems. In facial surgery, there are some AI-based software programs oriented to diagnosis in facial surgery. This study aims to evaluate the capacity and training of models for diagnosis of dentofacial deformities in class II and class III patients using artificial intelligence and the potential use for indicating orthognathic surgery. The search strategy is from 1943 to April 2024 in PubMed, Embase, Scopus, Lilacs, and Web of Science. Studies that used imaging to assess anatomical structures, airway volume, and craniofacial positions using the AI algorithm in the human population were included. The methodological quality of the studies was assessed using the Effective Public Health Practice Project instrument. The systematic search identified 697 articles. Eight studies were obtained for descriptive analysis after exclusion according to our inclusion and exclusion criteria. All studies were retrospective in design. A total of 5552 subjects with an age range between 14.7 and 56 years were obtained; 2474 (44.56%) subjects were male, and 3078 (55.43%) were female. Six studies were analyzed using 2D imaging and obtained highly accurate results in diagnosing skeletal features and determining the need for orthognathic surgery, and two studies used 3D imaging for measurement and diagnosis. Limitations of the studies such as age, diagnosis in facial deformity, and the included variables were observed. Concerning the overall analysis bias, six studies were at moderate risk due to weak study designs, while two were at high risk of bias. We can conclude that, with the few articles included, using AI-based software allows for some craniometric recognition and measurements to determine the diagnosis of facial deformities using mainly 2D analysis. However, it is necessary to perform studies based on three-dimensional images, increase the sample size, and train models in different populations to ensure accuracy of AI applications in this field. After that, the models can be trained for dentofacial diagnosis.

An Update on the Etiopathogenesis and Management of Morbihan Disease: A Narrative Review

: Morbihan disease (MD) is a rare and infrequent condition primarily affecting adults of both sexes in their third and fourth decades of life. Patients with MD typically present with asymptomatic, recurrent bilateral symmetrical pitting edema, which has an insidious onset and a progressive course. This edema affects the upper two-thirds of the face, including the forehead, glabella, periorbital area, cheeks, and nose, with or without erythema. Over time, it evolves into persistent solid, non-pitting, asymptomatic edema that is neither painful nor pruritic. Morbihan disease may cause facial contour deformity and sometimes narrowing of the visual field. The etiopathogenesis of MD remains unknown, and currently, there is no specific treatment for the condition. This review article provides an update on MD, aiming to increase awareness and knowledge about its etiopathogenesis and management.

Prenatal diagnosis of a severe form of frontonasal dysplasia with severe limb anomalies, hydrocephaly, a hypoplastic corpus callosum, and a ventricular septal defect using 3D ultrasound: a case report and literature review

BackgroundFrontonasal dysplasia (FND) is a rare congenital anomaly resulting from the underdevelopment of the frontonasal process, and it can be syndromic or nonsyndromic. The typical features of FND include a deformed nose and ocular hypertelorism, which are sometimes associated with cleft lip and/or palate. Only approximately 10 cases of prenatally diagnosed nonsyndromic FND have been reported in the past 30 years.Case presentationA 33-year-old woman (G2P1) was referred to our center at 20 gestational weeks for bilateral hydrocephaly. We detected typical features of FND, including severe hypertelorism, median nasal bifidity, a minor cleft lip, and multiple limb anomalies using three-dimensional (3D) ultrasound. A hypoplastic corpus callosum, unilateral microtia, and a ventricular septal defect were also detected. Genetic testing, including karyotype analysis, copy number variation (CNV) analysis, trio-whole exome sequencing (trio-WES), and trio-whole-gene sequencing (trio-WGS), was performed; however, we did not find any de novo gene variants in the fetus as compared to the parents. Postmortem examination confirmed the prenatal diagnosis of FND.ConclusionThe present case expands the wide phenotypic spectrum of prenatal FND patients. 3D ultrasound is a useful tool for detecting facial and limb deformities.

Sinonasal chondrosarcoma in a llama.

A 14-y-old intact female llama (Lama glama) was presented for evaluation of a right maxillary swelling of 3-mo duration. Clinically, the animal had mild nasal discharge, abnormal retropulsion of the right eye, and moderate gingival disease. An incisional biopsy of the maxillary mass revealed pleomorphic and mitotically active neoplastic spindle-to-stellate cells organized in haphazard lacunae embedded in abundant chondroid matrix. Given the poor prognosis, euthanasia was elected. Postmortem examination and sectioning of the head exposed a large solid, white, firm mass that vastly expanded the right infraorbital region, extending to the maxilla, effacing the right nasal conchae and ipsilateral zygomatic bone. Collectively, postmortem dissection, cytology, and histopathology of the primary mass supported a diagnosis of sinonasal chondrosarcoma. To our knowledge, this entity had not been reported previously in this species and should be considered a differential for facial deformities in New World camelids.

Mechanical Behavior of Geogrid Flexible Reinforced Soil Wall Subjected to Dynamic Load

The geogrid flexible reinforced soil wall is widely used in engineering practice. However, a more comprehensive understanding of the dynamic behavior of reinforced soil wall is still required for a more reasonable application. In order to explore the mechanical behavior of a geogrid flexible reinforced soil wall, the model test was carried out to investigate the dynamic deformation of geogrid reinforced soil wall subjected to a repeated load. The numerical simulation was also conducted for comparison and extension with regards to the earth pressure and the reinforcement strain. The change rules for the deformation of the wall face, the vertical earth pressure and the reinforcement strain subjected to dynamic load with four frequencies (4, 6, 8 and 10 Hz) and four amplitudes (30–60, 40–80, 50–100 and 60–120 kPa) were obtained. The factors that affect the mechanical behavior of geogrid flexible reinforced soil wall were analyzed. The results show that the dynamic deformation characteristics of reinforced soil wall are affected by the number of vibrations, the amplitude of dynamic load and the frequency of vibration. The maximum lateral displacement of the reinforced soil wall occurs on the third to the fifth layer. With an increase in dynamic load amplitude, the development of dynamic deformation gradually increases, and after a cumulative vibration of 200 × 104 times, the cumulative lateral deformation ratio and the cumulative vertical deformation ratio of the wall face is less than 1%. The vertical earth pressure of geogrid flexible reinforced soil wall increases partially along the length of the reinforcement, and the vertical earth pressure of the third layer is basically unchanged when subjected to a dynamic load. With an increase in vibration number, the change in the reinforcement strain of the third layer is more complex, and the change rules of the reinforcement strain of each layer are different. The reinforcement strain is small, with a maximum value of 0.1%.