Abstracts / British Journal of Oral and Maxillofacial Surgery 57 (2019) e76–e102 e89 Methods Lipoaspirate and cartilage samples were obtained from paediatric patients. Cells were isolated and expanded using established protocols. Cells were seeded in a range of bioink and printed using a pneumatic extrusion- based 3D bioprinter. Simultaneous printing of cell seeded bioink onto a PCL scaffold was achieved using a dual head bioprinting system. Bioprinted constructs were then chondro- genically differentiated and assessed for cartilage formation using staining for common cartilage markers including type I, II, X collagen as well as elastin. Results Cell survival following 3D bioprinting remains high within printed constructs. We demonstrate that both cells lines are suitable for 3D printing and that a high expression of collagen II is achieved in prints as detected by 2-photon fluo- rescence microscopy and histological staining. This indicates early cartilage formation and maturation of the extracellular matrix (ECM). Conclusion Tissue engineering and regenerative medicine aims to replace current surgical techniques that rely on costo- chondral harvesting and therefore eliminate their associated morbidity. Future research will focus on enhancing matura- tion of constructs in order to achieve cartilage that is clinically useful. This forms the focus of our future work. https://doi.org/10.1016/j.bjoms.2019.10.258 33 Demographic features of CERVicofacial infections. A maxillofacial trainee research collaborative (MTReC) project B. Dawoud ∗ , C. McDonald, A. Hennedige, G. Logan, S. Kent, A. Henry, R. Kulkarni, K. Gilbert, R. Exley, S. Basyuni, P. Kyzas, R. Morrison, J. McCaul, On behalf of the Maxillofacial Trainee Research Collaborative Leeds General Infirmary and University of Leeds Medical School Introduction/Aims Cervicofacial infection is one of the most common acute presentations to the Oral and Max- illofacial (OMFS) department. Little is known about the epidemiological features of this large patient cohort. Methods A multicentre, snapshot audit was performed by the Maxillofacial Trainee Research Collaborative across 17 hospitals in the UK from May to September 2017.Standard- ised forms were used to collect a broad range of information including epidemiological data and patient management. Results Data was gathered for 1002 admissions; 53.5 % male and 46.5 % female. Age ranged from 0-94 with an aver- age age of 37.3 years. Mean length of stay was 3.24 days with a range of 0-194 days. The Median ASA was 1 with a standard deviation of 0.61 and an interquartile range (IQR) of 1.0.The mandibular dentition was the most common source of infection (62 %). Mandibular molars were most frequently implicated (87.5 %). This was followed by the maxillary den- tition (20 %), skin/soft tissue (13 %) and salivary gland (5 %). Submandibular and buccal tissue spaces were the most fre- quent site of pus. Trismus was the most common presentation (37%) followed by dysphagia (21 %). Airway compromise was reported in 1 %. A total of 154 patients (15 %) received pre-operative steroids. Of this group 60 % had stridor, 41 % had voice change, 28 % reported dysphagia and 21 % had trismus. Conclusions Affected patients tend to be young and ASA 1. Preventable dental disease is the most common cause of infection. This condition can impart significant morbidity and require substantial resources in the current restrained environment. https://doi.org/10.1016/j.bjoms.2019.10.259 34 The development and progress of the maxillofacial trainee research collaborative (MTReC). How trainees can design and deliver national research projects C. McDonald ∗ , A. Hennedige, Greg Logan, S. Kent, A. Henry, B. Dawoud, R. Kulkarni, K. Gilbert, R. Exley, S. Basyuni, P. Kyzas, R. Morrison, J. McCaul, On behalf of the Maxillofacial Trainee Research Collaborative Aintree University Hospital, Liverpool Introduction The Maxillofacial Trainee Research Collab- orative (MTReC) is a committee of 9 trainees, 3 consultant advisers, and a national network of trainee regional leads and collaborators. It involves trainees of all grades in research and allows them to develop and recruit to national projects. We present the rationale behind trainee collabora- tives, how they can improve training, inform and change our practice. Materials / methods The use of steroids in cervicofacial infection was chosen as the first project. A systematic review was performed and published. A questionnaire assessing cur- rent practice was completed by consultants and trainees (92 % return rate, n = 324). This demonstrated clinical equipoise. A data collection plan was designed to investigate and define the current standard of care. A prospective trainee led snap- shot audit of acute admissions with cervicofacial infections to UK maxillofacial units was organised. Results One thousand and two patients were recruited from 17 sites. Data was remotely entered to a secure, central NHS server built for this purpose. This dataset defines the current standard of care in cervicofacial infection. Outcomes have been submitted as separate abstracts. This project was delivered with no funding, other than a BAOMS grant of £1000. Conclusions UK maxillofacial trainees are capable of designing and delivering large projects that can rapidly define, inform and change our practice. We are confident this improves our training and that trainees exposed to such projects will be more likely to recruit to trials once consul-