Orthognathic surgery aims to correct dentoskeletal and facial discrepancies. The expected benefits are functional, cosmetic, and psychological. In a previous publication, this group assessed the determinants of patient satisfaction to formulate the Northwick Park Orthognathic Questionnaire (NOQ). The aim of the present study was to validate this questionnaire. A total of 118 postoperative patients prospectively completed the NOQ, 30 of whom completed the questionnaire a second time. The mean completion rate was 87.6 ± 10%. Response reproducibility was high: 92% of patients gave identical responses (range 81-100%). The intra-class correlation coefficient (ICC) was 0.96 (0.96 ± 0.072). Average test-retest scores for each domain were as follows (range in parenthesis): reasons for treatment 93% (60-100%), preoperative experience 96% (81-100%), preparation for surgery 95% (81-100%), inpatient experience 89% (55-100%), post-discharge experience 83% (55-100%), benefits of treatment 92% (71-100%), overall patient education 91% (62-100%). Internal validity using Cronbach's alpha was 0.72 (standard deviation 0.23, range 0.5-1). The results confirm the consistency of responses and the reliability of the information collected with the NOQ. The NOQ is a novel questionnaire and a valid metric to quantify a patient's perception of their experience. Its adoption may aid in making targeted improvements to patient care.

Objectives COVIDTrach is a UK multicentre prospective cohort study project that aims to evaluate the outcomes of tracheostomy in patients with COVID-19 receiving mechanical ventilation and record the incidence of SARS-CoV-2 infection among healthcare workers involved in the procedure. Design Data on patient demographic, clinical history and outcomes were entered prospectively and updated over time via an online database (REDCap). Clinical variables were compared with outcomes, with logistic regression used to develop a model for mortality. Participants recorded whether any operators tested positive for SARS-CoV-2 within 2 weeks of the procedure. Setting UK National Health Service departments involved in treating patients with COVID-19 receiving mechanical ventilation. Participants The cohort comprised 1605 tracheostomy cases from 126 UK hospitals collected between 6 April and 26 August 2020. Main outcome measures Mortality following tracheostomy, successful wean from mechanical ventilation and length of time from tracheostomy to wean, discharge from hospital, complications from tracheostomy, reported SARS-CoV-2 infection among operators. Results The median time from intubation to tracheostomy was 15 days (IQR 11, 21). 285 (18%) patients died following the procedure. 1229 (93%) of the survivors had been successfully weaned from mechanical ventilation at censoring and 1049 (81%) had been discharged from hospital. Age, inspired oxygen concentration, positive end-expiratory pressure setting, fever, number of days of ventilation before tracheostomy, C reactive protein and the use of anticoagulation and inotropic support independently predicted mortality. Six reports were received of operators testing positive for SARS-CoV-2 within 2weeks of the procedure. Conclusions Tracheostomy appears to be safe in mechanically ventilated patients with COVID-19 and to operators performing the procedure and we identified clinical parameters that are predictive of mortality.

Maxillomandibular advancement (MMA) is reported in the literature as being as effective as continuous positive airway pressure (CPAP) for obstructive sleep apnoea (OSA). MMA for OSA is conventionally achieved by a combination of Le Fort 1 and bilateral sagital split advancement osteotomies (BSSO), usually accompanied by an advancement genioplasty.

Oxidized alginate hydrogels are appealing alternatives to natural alginate due to their favourable biodegradability profiles and capacity to self-crosslink with amine containing molecules facilitating functionalization with extracellular matrix cues, which enable modulation of stem cell fate, achieve highly viable 3-D cultures, and promote cell growth. Stem cell metabolism is at the core of cellular fate (proliferation, differentiation, death) and metabolomics provides global metabolic signatures representative of cellular status, being able to accurately identify the quality of stem cell differentiation. Herein, umbilical cord blood mesenchymal stem cells (UCB MSCs) were encapsulated in novel oxidized alginate hydrogels functionalized with the glycine-histidine-lysine (GHK) peptide and differentiated towards the osteoblastic lineage. The ADA-GHK hydrogels significantly improved osteogenic differentiation compared to gelatin-containing control hydrogels, as demonstrated by gene expression, alkaline phosphatase activity and bone extracellular matrix deposition. Metabolomics revealed the high degree of metabolic heterogeneity in the gelatin-containing control hydrogels, captured the enhanced osteogenic differentiation in the ADA-GHK hydrogels, confirmed the similar metabolism between differentiated cells and primary osteoblasts, and elucidated the metabolic mechanism responsible for the function of GHK. Our results suggest a novel paradigm for metabolomics-guided biomaterial design and robust stem cell bioprocessing. STATEMENT OF SIGNIFICANCE: Producing high quality engineered bone grafts is important for the treatment of critical sized bone defects. Robust and sensitive techniques are required for quality assessment of tissue-engineered constructs, which result to the selection of optimal biomaterials for bone graft development. Herein, we present a new use of metabolomics signatures in guiding the development of novel oxidised alginate-based hydrogels with umbilical cord blood mesenchymal stem cells and the glycine-histidine-lysine peptide, demonstrating that GHK induces stem cell osteogenic differentiation. Metabolomics signatures captured the enhanced osteogenesis in GHK hydrogels, confirmed the metabolic similarity between differentiated cells and primary osteoblasts, and elucidated the metabolic mechanism responsible for the function of GHK. In conclusion, our results suggest a new paradigm of metabolomics-driven design of biomaterials.

Orthognathic surgery aims to correct dentoskeletal and facial discrepancies. Treatment usually requires a minimum of 18 months, necessitating that patients are adequately satisfied with the treatment provided. This study aimed to assess the determinants of patient satisfaction following treatment. One hundred and eighteen patients who had undergone orthognathic surgery were included prospectively. All participants completed a questionnaire regarding their reasons for undergoing treatment, treatment logistics, treatment outcomes, and satisfaction throughout their journey. Most patients were 'very satisfied' (71.2%) or 'satisfied' (19.5%) with the overall treatment. The majority wished to improve their smile (78.0%); post-treatment, 89.0% of patients reported an improved smile. Almost half of the patients (46.6%) stayed in hospital for only one night, and 41.5% took over 4 weeks off work or school post-surgery. People with postoperative breathing difficulties spent more days in hospital (P = 0.021), but importantly, the duration of hospital stay did not differ between maxillary advancement, bilateral sagittal split osteotomy, and bimaxillary surgery (P = 0.78). In conclusion, patient satisfaction was high following orthognathic treatment. The results highlight areas for improvement, such as information delivery to the patient throughout the treatment journey, and show that the presence of ongoing problems is an important predictor of patient satisfaction.

The reconstruction of mandibular defects using particulate grafts is a proven technique that restores the osseous anatomy effectively. Secondary osseous reconstruction can be accomplished with endoscopic assistance and reduced-access incisions if an intermediate spacer is placed during resection. Two patients required reconstruction after resection of mandibular ameloblastomas. We used a modified protocol that involved the implantation of a graft of particulate corticocancellous bone after removal of the spacer, and prepared the recipient site under endoscopic guidance with small extraoral incisions. The grafts healed uneventfully and matured into ossicles suitable for the placement of osseointegrated implants.

Aim: To investigate factors affecting length of stay and readmission following orthognathic surgery.

We congratulate Abou-Foul et al on their success in teaching medical foundation trainees within their department in Oxford. 1 Abou-Foul A.K. Shah N.P. Mirza J. et al. Cross-cover of oral and maxillofacial surgery out-of-hours: an audit of a new adult treatment clinic. Br J Oral Maxillofac Surg. 2016; 54: 868-871 Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar We agree that the specialist nature of OMFS requires good training, and it is unfortunate that unfounded fear has created doubt over the safety of patients under the care of singly-qualified trainees.

Aim: To investigate the trends in patient number, demographics, procedure type and length of hospital stay (LOS) from 2004-2016.

Mesenchymal stem cells (MSCs) of fetal origin, such as umbilical cord blood MSCs (UCB MSCs), have emerged as a promising cell source for musculoskeletal tissue regeneration because of their higher proliferation potential, lack of donor site morbidity, and their off-the-shelf potential. MSCs differentiated toward the osteogenic lineage exhibit a specific metabolic phenotype characterized by reliance to oxidative phosphorylation for energy production and reduced glycolytic rates. Currently, limited information exists on the metabolic transitions at different stages of the osteogenic process after osteoinduction with different agents. Herein, the osteoinduction efficiency of BMP-2 and dexamethasone on UCB MSCs was assessed using gas chromatography-mass spectrometry (GC-MS) metabolomics analysis, revealing metabolic discrepancies at 7, 14, and 21 days of induction. Whereas both agents when administered individually were able to induce collagen I, osteocalcin, and osteonectin expression, BMP-2 was less effective than dexamethasone in promoting alkaline phosphatase expression. The metabolomics analysis revealed that each agent induced distinct metabolic alterations, including changes in amino acid pools, glutaminolysis, one-carbon metabolism, glycolysis, and tricarboxylic acid cycle. Importantly, we showed that in vitro-differentiated UCB MSCs acquire a metabolic physiology similar to primary osteoblasts when induced with dexamethasone but not with BMP-2, highlighting the fact that metabolomics analysis is sensitive enough to reveal potential differences in the osteogenic efficiency and can be used as a quality control assay for evaluating the osteogenic process.

Background: Surgical training is an apprenticeship system with trainees working under supervision until judged competent to operate independently. In the modern era advancements in technology have enabled surgical training to progress from simply assisting and performing a procedure under direct guidance. There have been developments in surgical simulation, with the production lifelike models progressing to virtual reality surgical simulation. Another such innovation is “Surgeon point of view recording”. This enables the trainer to broadcast and record the performance of a surgery and also for the trainee to be recorded and critiqued when working independently on call. Wearable technology opens many doors to further our surgical training as well providing another means of supervision. Objectives: To determine the use of surgical point of view recording using optical head-mounted display designed in the shape of a pair of eyeglasses as part of surgical training. Methods: Numerous surgical procedures from the full spectrum of maxillofacial surgery were recorded. Trainees were given use of the technology to use when on call and operating independently. Findings and Conclusion: Surgical point of view recording enhances the view of the surgical field especially in our specialty where conventional recording may not be able to visualise the full extent of the oral cavity or deep into the neck. Trainees found that critiquing operations where they worked independently greatly enhanced learning, especially for junior registrars (residents) and second degree students. It also provided an enhanced record of training to be used at their annual review of competence progression.

Background: Lefort I osteotomy is a common surgical procedure undertaken in Oral and Maxillofacial Surgical speciality. The midface is a complex structure involving the maxilla, nose with its hard and soft tissue structures. This includes the drainage of lacrimal and paranasal sinuses. One has to have a thorough understanding of three dimensional anatomical structures to avoid any damage to the adjacent structures. Here we report a rare complication of Lefort I osteotomy which results in blood in the tear duct (Haemolacria). Surgeons should be aware of this complication and its significance in this surgery.

#### What you need to knowA fit and well 25 year old man attends his local emergency department concerned about a bleeding tooth socket after having had a lower wisdom tooth extracted earlier that morning.Postoperative bleeding is a recognised complication after tooth extraction, with an incidence of up to 1.4% of patients undergoing lower wisdom tooth surgery.1 It can be difficult to achieve complete haemostasis within the oral cavity because of the highly vascular nature of the tissues and exposure of the open socket to the patient’s exploring tongue and fingers.2In healthy patients, a low level ooze for 12-24 hours after extraction is normal as an organised clot forms in the tooth socket.23 The patient will have mildly bloodstained saliva that will decrease over time. Any active bleeding beyond this point often indicates a haemostatic problem and requires investigations and treatment.4Significant, active haemorrhage must be addressed before taking a comprehensive history. It …

INTRODUCTION:The need for fracture healing enhancement for the management of fracture complications such as non-union and for the achievement of early function in fracture patients is constantly increasing. Therefore, the development and evaluation of novel pharmaceutical agents is mandatory in order to accelerate the process and increase bone union rates.AREAS COVERED:This review summarizes the most recent knowledge on the pharmacological enhancement of fracture repair. It provides a synopsis of the most important preclinical and clinical studies published over the past five years on long bone fracture healing.EXPERT OPINION:To date, limited drugs seem to have the potential for clinical use in fracture healing enhancement and the field is progressing very slowly. Among anti-osteoporotic drugs, only PTH and anti-sclerostin antibodies have such a potential but further research is needed before clinical use. The same applies also to BMPs, the use of which still carries major drawbacks that should be overcome before their widespread clinical utilization. Other drugs and growth factors, such as statins, VEGF, FGF, EPO, could be future key players in fracture healing but evidence is still lacking. Further in depth understanding of the healing process is essential in order to identify novel effective pharmacological agents.

Both the facial profile and a patient's self-esteem can be adversely affected by defects of the chin. Genioplasty is most commonly used for correction in all planes, including anteroposterior, sagittal, and vertical deficiencies. Using reduction genioplasty alone to correct a “prominent” chin can be associated with unpredictable postoperative stability and soft tissue changes. 1 Guyuron B. MOC-PS (SM) CME article: genioplasty. Plas Reconstr Surg. 2008; 121: 1-7 Google Scholar , 2 Uribe F. Janakiraman N. Shafer D. et al. Three-dimensional cone-beam computed tomography-based virtual treatment planning and fabrication of a surgical splint for asymmetric patients: surgery first approach. Am J Orthod Dentofacial Orthop. 2013; 144: 748-758 Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar , 3 Olszeweski R. Tranduy K. Reychler H. Innovative procedure for computer-assisted genioplasty: three-dimensional cephalometry, rapid-prototyping model and surgical splint. Int J Oral Maxillofac Surg. 2010; 39: 721-724 Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar , 4 Park J.Y. Kim M.J. Hwang S.J. Soft tissue profile changes after setback genioplasty in orthognathic surgery patients. J Craniomaxillofac Surg. 2013; 41: 657-664 Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar

Introduction: Temporomandibular joint (TMJ) pathology is increasingly common in the UK. Increasingly, prosthetic replacement is gaining acceptance as a gold standard in managing surgically refractory cases. Facial nerve paresis and palsy remains a crippling complication of the procedure.

Chapter 25 Mandibular Set-Back Procedures Manolis Heliotis, Manolis HeliotisSearch for more papers by this authorShamique Ismail, Shamique IsmailSearch for more papers by this author Manolis Heliotis, Manolis HeliotisSearch for more papers by this authorShamique Ismail, Shamique IsmailSearch for more papers by this author Book Editor(s):Farhad B. Naini BDS (Lond.), MSc (Lond.), PhD (KCL), FDS.RCS (Eng.), M.Orth.RCS (Eng.), FDS.Orth.RCS (Eng.), GCAP (KCL), FHEA, Farhad B. Naini BDS (Lond.), MSc (Lond.), PhD (KCL), FDS.RCS (Eng.), M.Orth.RCS (Eng.), FDS.Orth.RCS (Eng.), GCAP (KCL), FHEA Kingston Hospital and St George's Hospital and Medical School, Consultant Orthodontist, London, UKSearch for more papers by this authorDaljit S. Gill BDS (Hons), BSc (Hons), MSc (Lond.), FDS.RCS (Eng.), M.Orth.RCS (Eng.), FDS (Orth) RCS (Eng.), FHEA, Daljit S. Gill BDS (Hons), BSc (Hons), MSc (Lond.), FDS.RCS (Eng.), M.Orth.RCS (Eng.), FDS (Orth) RCS (Eng.), FHEA Great Ormond Street Hospital NHS Foundation Trust and UCLH Eastman Dental Hospital, Consultant Orthodontist, London, UKSearch for more papers by this author First published: 16 December 2016 https://doi.org/10.1002/9781119004370.ch25 AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Abstract The orthodontic preparation for a combined orthog-nathic case, requiring a mandibular set-back procedure, is focused initially on addressing the aforementioned preexisting dental compensation, whilst acknowledging the biological and physiological boundaries of the tissues in the area. Measurement of the mandibular dentoalveolar height on the lateral cephalometric radiograph may also be of some assistance in cases of mandibular prog-nathism where the clinical presentation also includes an anterior open bite. The most common operation for a mandibular set-back procedure is the bilateral sagittal split osteotomy (BSSO). However, it has become increasingly recognised that if a large set-back is required, the most stable procedure in terms of surgical outcome that can be offered is the intraoral vertical subsigmoid osteotomy (IVSSO). The treatment plan is then moulded with cephalo-metric based predictive profile manipulation methods and shared between the patient, surgeon and orthodontist to determine the best functional and aesthetic outcome suitable to the individual patient. Orthognathic Surgery: Principles, Planning and Practice, First Edition RelatedInformation

Conditioned medium from human hepatocarcinoma cells (HepG2-CM) has been shown to stimulate the osteogenic/chondrogenic differentiation of murine embryonic stem cells (mESCs). HepG2-CM is considered to contain visceral endoderm (VE)-like signals and attempts have recently been made to characterize it, using proteomic profiling, with fibronectin being identified as one promising candidate. Herein, we investigated whether fibronectin is able to mimic the activities of HepG2-CM during the osteogenic differentiation of mESCs. Specifically, the addition of RGD peptides and heparin in HepG2-CM significantly reduced the growth- and adhesion-promoting effects of HepG2-CM, in addition to suppressing its osteogenic-inductive activity. Furthermore, direct addition of fibronectin to basal medium was able to reproduce, at least partially, the function of HepG2-CM. In particular, fibronectin induced the early onset of osteogenic differentiation in mESCs, as confirmed by gene expression of osteogenic markers, and resulted in the three-fold higher calcium deposition at day 11 of osteogenic culture compared to the control group. These data clearly suggest that fibronectin contributes to the biological activities of HepG2-CM and plays a stimulatory role during the process of osteogenesis in mESCs. Copyright © 2015 John Wiley & Sons, Ltd.

Introduction: The production of functional alternatives to bone autografts and the development new treatment strategies for cartilage defects are great challenges that could be addressed by the field of tissue engineering. Umbilical cord mesenchymal stem cells (MSCs) can be used to produce cost-effective, atraumatic and possibly autologous bone and cartilage grafts.Areas covered: MSCs can be isolated from umbilical cord Wharton's jelly, perivascular tissue and blood using various techniques. Those cells have been characterized and phenotypic similarities with bone marrow-derived MSCs (BM-MSCs) and embryonic stem cells have been found. Findings on their differentiation into the osteogenic and chondrogenic lineage differ between studies and are not as consistent as for BM-MSCs.Expert opinion: MSCs from umbilical cords have to be more extensively studied and the mechanisms underlying their differentiation have to be clarified. To date, they seem to be an attractive alternative to BM-MSCs. However, further research with suitable scaffolds and growth factors as well as with novel scaffold fabrication and culture technology should be conducted before they are introduced to clinical practice and replace BM-MSCs.