Efficiency of advanced-PRF usage in the treatment of alveolar cleft with iliac bone graft: A retrospective study

The aim of this study was to evaluate the efficiency of a new alveolar bone grafting protocol using advanced-PRF (a-PRF) by comparing the volumes of newly formed bone after a bone graft combining autogenous iliac crest bone with either PRF or a-PRF. Patients presenting with unilateral or a bilateral alveolar cleft were included retrospectively in two groups: one group was grafted using cancellous iliac crest bone with PRF (PRF group), whereas for the other group the same procedure was followed using a-PRF (a-PRF group). CBCT scans were performed 3 months preoperatively and 6 months postoperatively. The volume of newly formed bone was measured by subtracting the postoperative cleft volume from the preoperative cleft volume. The mean volume of newly formed bone was compared between the two groups using Student's t-test. Twenty-four patients were included, with 12 allocated to each group. Forty-eight CBCT scans were analyzed. The mean volume of newly formed bone was 0.29 (±0.09) cm³ in the a-PRF group, versus 0.20 (±0.08) cm³ in the PRF group (Student's t-test, p = 0.024). The percentage of newly formed bone was 60.4 (±10.4) % in the a-PRF group versus 51.4 (±18.4) % in the PRF group (Student's t-test, p = 0.165). Our study demonstrated improved bone regeneration in the a-PRF group. While bearing in mind the limitations of this study, the a-PRF procedure should be adopted in cleft bone grafting whenever possible.

[Odyssey of the iliac. "Mandibular reconstruction by bone free flaps"]

The authors proposed here a retrospective analysis of a surgical procedure they performed for long time. It allows to put into questions some established principles, to find some unkwown datas which could be important to predict complications. It is also interesting to discuss about the use of indication and choice of the flaps along years of reconstructive surgery history in the way to improve protocoles and management of those large reconstruction. During ten years in one maxillofacial surgery departement, more than 200 bone free flaps (essentially fibula and iliac crest) have been used for mandibular reconstruction and analyse with a three years follow-up. The global failure rate is estimated as 28 % included all various complications from fistulas to infections. Five different points are discussed from the ambiguity of the reported studies to the way of doing of such surgery. It is also pointed out the importance of the biological dimension of all surgical procedures and the place of clinical figures regarding of the technical processes which usually forget the main clinical purpose.

Kinect-driven Patient-specific Head, Skull, and Muscle Network Modelling for Facial Palsy Patients

BACKGROUND AND OBJECTIVE

Facial palsy negatively affects both professional and personal life qualities of involved patients. Classical facial rehabilitation strategies can recover facial mimics into their normal and symmetrical movements and appearances. However, there is a lack of objective, quantitative, and in-vivo facial texture and muscle activation bio-feedbacks for personalizing rehabilitation programs and diagnosing recovering progresses. Consequently, this study proposed a novel patient-specific modelling method for generating a full patient specific head model from a visual sensor and then computing the facial texture and muscle activation in real-time for further clinical decision making.

METHODS

The modeling workflow includes (1) Kinect-to-head, (2) head-to-skull, and (3) muscle network definition & generation processes. In the Kinect-to-head process, subject-specific data acquired from a new user in neutral mimic were used for generating his/her geometrical head model with facial texture. In particular, a template head model was deformed to optimally fit with high-definition facial points acquired by the Kinect sensor. Moreover, the facial texture was also merged from his/her facial images in left, right, and center points of view. In the head-to-skull process, a generic skull model was deformed so that its shape was statistically fitted with his/her geometrical head model. In the muscle network definition & generation process, a muscle network was defined from the head and skull models for computing muscle strains during facial movements. Muscle insertion points and muscle attachment points were defined as vertex positions on the head model and the skull model respectively based on the standard facial anatomy. Three healthy subjects and two facial palsy patients were selected for validating the proposed method. In neutral positions, magnetic resonance imaging (MRI)-based head and skull models were compared with Kinect-based head and skull models. In mimic positions, infrared depth-based head models in smiling and [u]-pronouncing mimics were compared with appropriate animated Kinect-driven head models. The Hausdorff distance metric was used for these comparisons. Moreover, computed muscle lengths and strains in the tested facial mimics were validated with reported values in literature.

RESULTS

With the current hardware configuration, the patient-specific head model with skull and muscle network could be fast generated within 17.16±0.37s and animated in real-time with the framerate of 40 fps. In neutral positions, the best mean error was 1.91 mm for the head models and 3.21 mm for the skull models. On facial regions, the best mean errors were 1.53 mm and 2.82 mm for head and skull models respectively. On muscle insertion/attachment point regions, the best mean errors were 1.09 mm and 2.16 mm for head and skull models respectively. In mimic positions, these errors were 2.02 mm in smiling mimics and 2.00 mm in [u]-pronouncing mimics for the head models on facial regions. All above error values were computed on a one-time validation procedure. Facial muscles exhibited muscle shortening and muscle elongating for smiling and pronunciation of sound [u] respectively. Extracted muscle features (i.e. muscle length and strain) are in agreement with experimental and literature data.

CONCLUSIONS

This study proposed a novel modeling method for fast generating and animating patient-specific biomechanical head model with facial texture and muscle activation bio-feedbacks. The Kinect-driven muscle strains could be applied for further real-time muscle-oriented facial paralysis grading and other facial analysis applications.

Impact of the COVID-19 lockdown on the epidemiology of maxillofacial trauma activity: a French multicentre comparative study

The coronavirus disease 2019 (COVID-19) outbreak has had a major impact on medical and surgical activities. A decline in facial trauma incidence was noticed during the lockdown period. The aim of this study was to evaluate the decline in maxillofacial trauma in France during this particular period. A retrospective multicentre comparative study was initiated in 13 major French public hospital centres. The incidence of facial trauma requiring surgery during the first month of lockdown was compared to that during equivalent periods in 2018 and 2019. Differences in the types of trauma were also analysed. Thirteen maxillofacial departments participated in the study. A significant decline in maxillofacial trauma volumes was observed when compared to equivalent periods in 2018 and 2019 (106 patients compared to 318 and 296 patients, respectively), with an average reduction of 65.5% (P = 0.00087). The proportion of trauma due to sports and leisure was reduced when compared to reports in the literature. As a consequence, in the context of a pandemic, the material and human resources related to this activity could be reallocated to the management of other pathologies that cannot be postponed.

A prospective multicentre REFCOR study of 470 cases of head and neck Adenoid cystic carcinoma: epidemiology and prognostic factors

BACKGROUND

Adenoid cystic carcinoma (ACC) accounts for 1% of malignant head and neck tumours [1] and 10% of salivary glands malignant tumours. The main objective of our study is to investigate the prognostic factors influencing the event-free survival (EFS) of patients with ACC.

PATIENTS AND METHODS

A multicentre prospective study was conducted from 2009 to 2018. All 470 patients with ACC whose survival data appear in the REFCOR database were included in the study. The main judgement criterion was EFS. Both a bivariate survival analysis using log-rank test and a multivariate using Cox model were performed using the R software.

RESULTS

Average age was 55 years. Females accounted for 59.4% of the cohort. The body mass index (BMI) was normal in 86% of cases. Tumours were located in minor salivary glands in 60% of cases. T3/T4 stages represented 58%; 89% of patients were cN0. histological grade III was observed on 21% of patients. The EFS and overall 5-year survival rates were 50% and 85%, respectively. After adjustment, the most significant pejorative prognostic factors were age ≥65 years (hazard ratio [HR] = 1.67), BMI<16.5 (HR = 2.62), and lymph node invasion cN (HR = 2.08).

CONCLUSION

Age, BMI and N stage are the three main clinical prognostic factors determining EFS identified in this prospective series of patients with ACC. Such findings open new research perspectives on the influence of these components on initial patient care.

Fraser syndrome: review of the literature illustrated by a historical adult case

Fraser syndrome (cryptophthalmos-syndactyly syndrome) is a rare autosomal recessive malformation disorder. The first description of the syndrome was reported by George Fraser in 1962. Diagnosis is based on the major and minor criteria established by van Haelst et al. in 2007. Unilateral or bilateral cryptophthalmos, syndactyly, unilateral renal agenesis, and genital anomalies are the most frequent anomalies. Several maxillofacial, oro-dental, ear-nose-throat, hormonal, and anorectal disorders are reported. Cardiac malformations and musculoskeletal anomalies are uncommon. The syndrome is related to mutations in three different genes (FRAS1, FREM2, and GRIP1) resulting in failure of the apoptosis program and disruption of the epithelial-mesenchymal interactions during embryonic development. Prenatal diagnosis is based on the detection of renal agenesis and laryngeal atresia, together with a family history. Most foetuses with severe anomalies are terminated or are stillborn. All patients or pregnancies with a diagnosis of Fraser syndrome should be referred to expert centres. A collaborative approach including anaesthetists, ENT specialists, maxillofacial surgeons, and geneticists is necessary for the management of this syndrome. In vivo and in vitro research models are available to better understand the underlying aetiology.

Real-time Subject-specific Head and Facial Mimic Animation System using a Contactless Kinect Sensor and System of Systems Approach

Facial palsies due to stroke, accidental and sportive injuries or sometimes without etiology, affect the professional and personal lives of involved patients. These disorders are not only a functional handicap but also a social integration impairment. The recovery of facial mimics with a normal and symmetrical facial expression allows involved patients to improve their living conditions and social identity. Current approaches lack of visual feedbacks. To monitor facial mimics and head movements in a quantitative and objective manners, a computer-aided animation system needs to be developed. Numerous systems have been proposed using single camera, stereo camera, 3-D scanner, and Kinect approaches. In particular, Kinect contactless sensor has been proven to be very suitable for 3-D facial simulation applications. However, little studies have employed the Kinect sensor for real-time head animation applications. Consequently, this study developed a real-time head and facial mimic animation system using the contactless Kinect sensor and the system of systems approach. To evaluate the accuracy of the subject-specific Kinect-based geometrical models, magnetic resonance imaging (MRI) data were used. As results, the mean distance deviation between generated Kinect-based and reconstructed MRI-based geometrical head models are approximately 1 mm for two tested subjects. The generation times are 9.7 s ± 0.3 and 0.046 s ± 0.005 by using the full facial landmarks and MPEG-4 facial landmarks respectively. Real-time head and facial mimic animations were illustrated. Particularly, the system could be executed at a very high framerate (60 fps). Further developments relate to the integration of texture information and internal structures such as a skull and muscle network to develop a full subject specific head and facial mimic animation system for facial mimic rehabilitation.

MMP3 Is a Non-invasive Biomarker of Rejection in Skin-Bearing Vascularized Composite Allotransplantation: A Multicenter Validation Study

Background: There is unmet need for non-invasive immunomonitoring to improve diagnosis and treatment of acute rejection in vascularized composite allotransplantation (VCA). Circulating matrix metalloproteinase 3 (MMP3) was described as a candidate non-invasive biomarker to predict treatment response to acute rejection in clinical VCA. However, larger validation studies are yet to be reported to allow for more definitive conclusions.

Methods: We retrospectively measured MMP3 levels using ELISA in a total of 140 longitudinal serum samples from six internal and three external face transplant recipients, as well as three internal and seven external upper extremity transplant recipients. The control groups comprised serum samples from 36 kidney transplant recipients, 14 healthy controls, and 38 patients with autoimmune skin disease. A linear mixed model was used to study the effect of rejection state (pre-transplant, no-rejection, non-severe rejection (NSR), and severe rejection) on MMP3 levels.

Results: In VCA, MMP3 levels increased significantly (p < 0.001) between pre- and post-transplant no-rejection states. A further increase occurred during severe rejection (p < 0.001), while there was no difference in MMP3 levels between non-severe and no-rejection episodes. A threshold of 5-fold increase from pre-transplant levels could discriminate severe from NSR with 76% sensitivity and 81% specificity (AUC = 0.79, 95% CI = 0.65–0.92, p < 0.001). In kidney transplantation, the MMP3 levels were significantly (p < 0.001) elevated during antibody-mediated rejection but not during T-cell mediated rejection (TCMR) (p = 0.547). MMP3 levels in healthy controls and autoimmune skin disease patients were comparable with either pre-transplant or no-rejection/NSR episodes of VCA patients.

Conclusion: The results of this study suggest that serum MMP3 protein is a promising marker for stratifying patients according to severity of rejection, complementary to biopsy findings.

Likely Pathogenic Variants in One Third of Non-Syndromic Discontinuous Cleft Lip and Palate Patients

Oral clefts are composed of cleft of the lip, cleft of the lip and palate, or cleft of the palate, and they are associated with a wide range of expression and severity. When cleft of the palate is associated with cleft of the lip with preservation of the primary palate, it defines an atypical phenotype called discontinuous cleft. Although this phenotype may represent 5% of clefts of the lip and/or palate (CLP), it is rarely specifically referred to and its pathophysiology is unknown. We conducted whole exome sequencing (WES) and apply a candidate gene approach to non-syndromic discontinuous CLP individuals in order to identify genes and deleterious variants that could underlie this phenotype. We discovered loss-of-function variants in two out of the seven individuals, implicating FGFR1 and DLG1 genes, which represents almost one third of this cohort. Whole exome sequencing of clinically well-defined subgroups of CLP, such as discontinuous cleft, is a relevant approach to study CLP etiopathogenesis. It could facilitate more accurate clinical, epidemiological and fundamental research, ultimately resulting in better diagnosis and care of CLP patients. Non-syndromic discontinuous cleft lip and palate seems to have a strong genetic basis.

Anatomical study of the course of the inferior alveolar nerve in craniofacial microsomia using three-dimensional computed tomography: correlation with the Pruzansky classification

Dysmorphogenesis of the mandible complicates assessment of the course of the inferior alveolar nerve in patients with craniofacial microsomia. Our aim in the present study was to correlate the anatomical description of the course with the Pruzansky classification (which indicates the severity of hemifacial microsomia), in the mandibles of 22 affected patients using 3-dimensional computed tomography (CT). We measured the distance between fixed landmarks on the normal and the microsomic sides. The normal sides served as controls. In the group of five patients with type I disease, we found no significant differences between the unaffected and the microsomic side. In the nine patients with Pruzansky type II disease morphological views of the course showed a between-side difference in the length of the bony canal and the height of the mandibular ramus. In the five patients with Pruzansky type III disease, there was no bony canal. Three-dimensional CT analysis may be of value in plotting the course of the inferior alveolar nerve and assisting the surgeon in mandibular osteotomy or distraction osteogenesis.

[Facial graft, archetype of microsurgical innovation?]

Is innovation breaking of the way of thinking, breaker of taboos, concretisation of chimeras or simple benefit of an ineluctable evolution? The surgical act should be considered as innovation itself? From the first facial allotransplantation, innovation is declined in various ways, which could constitute the different answers regarding the planning and management to prepare such surgery, the realisation of the transplantation and also the multiple developments in terms of science and medicine. It is exactly in that meaning that could be really mentioned the term archetypal.

«Greffe de visage»: regards portés sur la première allotransplantation composite partielle de la face

The first facial allograft was realised in Amiens 2005 November 27th. Breaking the technical limits of the so called possible and in appearance transgressing some cultural forbidden in organ transplantation, this resolutely innovative intervention open more than new perspective in the surgery of the reconstruction after disfigurement, but also a wide field of scientific investigations about dynamic and meaning of the facial function. Obviously, it also deals with numerous ethical and medical problems. The authors here shortly described the technical points of the surgery firstly done to restore oral function and facial expressively, the principles of the immunosuppressive treatment built to control any rejection time episode and the anatomical, neurological and functional results obtained after more than 18 months follow-up. Those perfectly demonstrate the perfect morphological, dynamic and cortical integration of the graft in the recomposed face. They also allow to confirm the legitimacy of the surgical indication and to oppose the factual objective arguments to the ethical reticences dealing with the facial and psychological identity of the receptor.