Oral surgery in people with inherited bleeding disorder: A retrospective study.

INTRODUCTION: The objectives were to describe the peri-operative management of people with inherited bleeding disorders in oral surgery and to investigate the association between type of surgery and risk of developing bleeding complications. MATERIALS AND METHODS: This retrospective observational study included patients with haemophilia A or B, von Willebrand disease, Glanzmann thrombasthenia or isolated coagulation factor deficiency such as afibrinogenemia who underwent osseous (third molar extraction, ortho-surgical traction, dental implant placement) or nonosseous oral surgery between 2014 and 2021 at Bordeaux University Hospital (France). Patients and oral surgery characteristics were retrieved from medical records. Odds ratio (OR) and 95% confidence interval (CI) were estimated using logistic regression. RESULTS: Of the 83 patients included, general anaesthesia was performed in 16%. Twelve had a bleeding complication (14.5%) including six after osseous surgery. The most serious complication was the appearance of anti-FVIII inhibitor in a patient with moderate haemophilia A. All bleeding complications were managed by a local treatment and factor injections where indicated. No association was observed between type of surgery (osseous vs. nonosseous) and risk of bleeding complications after controlling for sex, age, disease type and severity, multiple extractions, type of anaesthesia and use of fibrin glue (OR: 3.21, 95% CI: .69-14.88). CONCLUSION: In this study, we have observed that bleeding complications after oral surgery in people with inherited bleeding disorders were moderately frequent and easily managed. However, in this study, we observed a serious complication highlighting the necessity of a thorough benefit-risk balance evaluation during the preoperative planning of the surgical and medical protocol.

Oral potentially malignant disorders - An assessment of knowledge and attitude to future education in undergraduate dental students.

INTRODUCTION: The aim of this study was to assess the knowledge and clinical experience of oral potentially malignant disorders (OPMDs) in undergraduate dental students in six European countries (Croatia, France, Italy, Portugal, Spain and United Kingdom) and assess student's attitude and preference to future education on the topic. A secondary aim was to identify gaps in student's knowledge and clinical practice. The study was a part of the Erasmus+ project "Oral Potentially Malignant Disorders: Healthcare Professionals Training" (Grant No: 2020-1-UK01-KA202-078917). MATERIALS AND METHODS: An online questionnaire was distributed to all final-year students in six partner universities. This consisted of four parts assessing: (1) knowledge on OPMDs, (2) clinical experience with this group of patients, (3) self-rated competence in the management of OPMDs and (4) preferences with regard to future education. RESULTS: Two hundred and sixty final-year dental students from six partner universities responded to the questionnaire. Response rates varied from 12% to 92% between partner universities. Significant differences in clinical experience and knowledge were found between students. Students with more clinical exposure to OPMDs rated their knowledge and competence in the management of OPMDs higher than students with less clinical experience. The majority of students were interested in future education on OPMDs, preferably via short educational videos. CONCLUSION: The majority of students have received theoretical knowledge of OPMDs during their undergraduate studies, however, not all had clinical exposure to this group of patients. Students were open to further education on OPMDs. Important deficiencies in knowledge were identified that need to be addressed and it is anticipated that the e-learning platform and e-book that are in development by partner institutions will help to improve overall knowledge of OPMDs.

Micropatterning of endothelial cells to create a capillary-like network with defined architecture by laser-assisted bioprinting.

Development of a microvasculature into tissue-engineered bone substitutes represents a current challenge. Seeding of endothelial cells in an appropriate environment can give rise to a capillary-like network to enhance prevascularization of bone substitutes. Advances in biofabrication techniques, such as bioprinting, could allow to precisely define a pattern of endothelial cells onto a biomaterial suitable for in vivo applications. The aim of this study was to produce a microvascular network following a defined pattern and preserve it while preparing the surface to print another layer of endothelial cells. We first optimise the bioink cell concentration and laser printing parameters and then develop a method to allow endothelial cells to survive between two collagen layers. Laser-assisted bioprinting (LAB) was used to pattern lines of tdTomato-labeled endothelial cells cocultured with mesenchymal stem cells seeded onto a collagen hydrogel. Formation of capillary-like structures was dependent on a sufficient local density of endothelial cells. Overlay of the pattern with collagen I hydrogel containing vascular endothelial growth factor (VEGF) allowed capillary-like structures formation and preservation of the printed pattern over time. Results indicate that laser-assisted bioprinting is a valuable technique to pre-organize endothelial cells into high cell density pattern in order to create a vascular network with defined architecture in tissue-engineered constructs based on collagen hydrogel.

Layer-by-layer bioassembly of cellularized polylactic acid porous membranes for bone tissue engineering.

The conventional tissue engineering is based on seeding of macroporous scaffold on its surface ("top-down" approach). The main limitation is poor cell viability in the middle of the scaffold due to poor diffusion of oxygen and nutrients and insufficient vascularization. Layer-by-Layer (LBL) bioassembly is based on "bottom-up" approach, which considers assembly of small cellularized blocks. The aim of this work was to evaluate proliferation and differentiation of human bone marrow stromal cells (HBMSCs) and endothelial progenitor cells (EPCs) in two and three dimensions (2D, 3D) using a LBL assembly of polylactic acid (PLA) scaffolds fabricated by 3D printing. 2D experiments have shown maintain of cell viability on PLA, especially when a co-cuture system was used, as well as adequate morphology of seeded cells. Early osteoblastic and endothelial differentiations were observed and cell proliferation was increased after 7 days of culture. In 3D, cell migration was observed between layers of LBL constructs, as well as an osteoblastic differentiation. These results indicate that LBL assembly of PLA layers could be suitable for BTE, in order to promote homogenous cell distribution inside the scaffold and gene expression specific to the cells implanted in the case of co-culture system.

Web-Based Information on the Treatment of Tobacco Dependence for Oral Health Professionals: Analysis of English-Written Websites.

BACKGROUND: Studies have been conducted on the content and quality of Web-based information for patients who are interested in smoking cessation advice and for health care practitioners regarding the content of e-learning programs about tobacco cessation. However, to the best of our knowledge, there is no such information about the quality of Web-based learning resources regarding smoking cessation dedicated to oral health professionals. OBJECTIVE: The aim of this study was to identify and evaluate the quality of the content of webpages providing information about smoking cessation for oral health care professionals. METHODS: Websites were identified using Google and Health on Net (HON) search engines using the terms: smoking cessation OR quit smoking OR stop smoking OR 3As OR 5As OR tobacco counselling AND dentistry OR dental clinic OR dentist OR dental hygienist OR oral health professionals. The first 100 consecutive results of the 2 search engines were considered for the study. Quality assessment was rated using the DISCERN questionnaire, the Journal of the American Medical Association (JAMA) benchmarks, and the HON seal. In addition, smoking cessation content on each site was assessed using an abbreviated version of the Smoke Treatment Scale (STS-C) and the Smoking Treatment Scale-Rating (STS-R). To assess legibility of the selected websites, the Flesch Reading Ease (FRES) and the Flesch-Kinkaid Reading Grade Level (FKRGL) were used. Websites were also classified into multimedia and nonmultimedia and friendly and nonfriendly usability. RESULTS: Of the first 200 sites selected (100 of Google and 100 of HON), only 11 met the inclusion criteria and mainly belonged to governmental institutions (n=8), with the others being prepared by Professional Associations (n=2) and nonprofit organizations (n=1). Only 3 were exclusively dedicated to smoking cessation. The average score obtained with the DISCERN was 3.0, and the average score in the FKRGL and FRES was 13.31 (standard deviation, SD 3.34) and 40.73 (SD 15.46), respectively. Of the 11 websites evaluated, none achieved all the four JAMA benchmarks. The mean score of STS-R among all the websites was 2.81 (SD 0.95) out of 5. A significant strong positive correlation was obtained between the DISCERN mean values and the STS-R (R=.89, P=.01). CONCLUSIONS: The mean quality of webpages with information for oral health care professionals about smoking cessation is low and displayed a high heterogeneity. These webpages are also difficult to read and often lack multimedia resources, which further limits their usefulness.

[Uses of 3D printing and Bioprinting for pre-implant bone reconstruction in Oral Surgery]. / Impression 3D et bioimpression pour la régénération osseuse en chirurgie orale.

Pre-implant bone surgery in oral surgery allows to reconstruct maxillary atrophies related to traumatic, infectious or tumoral processes. In this context, the ideal biomaterial remains autogenous bone, but biomaterials (of natural or synthetic origin) allow to limit the morbidity linked to bone harvesting, and to simplify these surgical procedures. In this article, we illustrate how 3D printing technologies can be used as an adjuvant to treat bone defects of complex shape or to create anatomical models used to plan interventions. Finally, some perspectives brought by tissue engineering and bioprinting (creation of complex in vitro models) are presented.

Title: Impression 3D et bioimpression pour la régénération osseuse en chirurgie orale. Abstract: La chirurgie osseuse pré-implantaire en chirurgie orale permet de reconstruire les atrophies des maxillaires en rapport avec des processus traumatiques, infectieux ou tumoraux. Dans ce contexte, le biomatériau idéal reste l'os autogène mais les biomatériaux (d'origine naturelle ou synthétique) permettent de limiter la morbidité liée aux prélèvements osseux et de simplifier ces interventions chirurgicales. Dans cet article, nous illustrons l'apport récent de l'impression 3D dans ce contexte pour traiter des défauts osseux de forme complexe ou pour créer des modèles anatomiques servant à planifier les interventions. Enfin, les perspectives apportées par l'ingénierie tissulaire et la bioimpression (création de modèles in vitro complexes) sont détaillées.

Revolutionizing Dental Implant Research: A Systematic Review on Three-Dimensional In Vitro Models.

Dental implants have been clinically used for almost five decades with high success rates. In vitro research models used in implant dentistry are limited to two-dimensional experiments, which are reproducible and well adapted to evaluate a single parameter but do not reproduce the complexity of clinical settings. On the contrary, the in vivo research models using animals offer similar histological and anatomical features to humans, and tissue healing can be close to a clinical situation, but those models are usually accompanied with ethical concerns, and their outcomes could not be extrapolated to humans because of interspecies variabilities. This makes the development of novel in vitro models that recapitulate physiological events occurring during dental implant placement of particular interest for current research in dentistry. Also, such models could be challenged by setting a pathological environment (peri-implantitis) to better understand the disease and eventually serve as a platform to evaluate novel treatment modalities. The aim of this systematic literature review was to cover all the in vitro three-dimensional (3D) complex models available for research in implant dentistry. To accomplish this, a comprehensive search of the literature present on Scopus and PubMed databases was done using specific keywords, as well as inclusion/exclusion criteria. Out of 1334 articles found, we have finally included 27 articles in this review with publication dates between 2001 and 2022. In those articles, the 3D models were designed to study tissue-implant interface behavior in bone or gingival tissue. The articles focused on simulating implant integration, evaluating the effect of different conditions on implant integration, or developing an infection model for the implant integration process. The methods used involved implant material and cells organized in a specific 3D structure. The 3D models developed were able to simulate the process of dental implant osseo- and soft tissue integration and lead to results comparable with conventional in vitro and in vivo models. A relatively limited number of articles were obtained, which indicates that this is an emerging field, highly dependent on progresses made in biotechnologies and tissue engineering, and that further investigation is needed to enhance these 3D in vitro models.

An Elastin-Derived Composite Matrix for Enhanced Vascularized and Innervated Bone Tissue Reconstruction: From Material Development to Preclinical Evaluation.

Despite progress in bone tissue engineering, reconstruction of large bone defects remains an important clinical challenge. Here, a biomaterial designed to recruit bone cells, endothelial cells, and neuronal fibers within the same matrix is developed, enabling bone tissue regeneration. The bioactive matrix is based on modified elastin-like polypeptides (ELPs) grafted with laminin-derived adhesion peptides IKVAV and YIGSR, and the SNA15 peptide for retention of hydroxyapatite (HA) particles. The composite matrix shows suitable porosity, interconnectivity, biocompatibility for endothelial cells, and the ability to support neurites outgrowth by sensory neurons. Subcutaneous implantation leads to the formation of osteoid tissue, characterized by the presence of bone cells, vascular networks, and neuronal structures, while minimizing inflammation. Using a rat femoral condyle defect model, longitudinal micro-CT analysis is performed, which demonstrates a significant increase in the volume of mineralized tissue when using the ELP-based matrix compared to empty defects and a commercially available control (Collapat). Furthermore, visible blood vessel networks and nerve fibers are observed within the lesions after a period of two weeks. By incorporating multiple key components that support cell growth, mineralization, and tissue integration, this ELP-based composite matrix provides a holistic and versatile solution to enhance bone tissue regeneration.

Frequency of barodontalgia among military or civilian pilots and aircrew members.

BACKGROUND: Barodontalgia is dental pain triggered by a change in barometric pressure and can be severe enough to cause in-flight incapacitation. There is a large variation of in-flight barodontalgia incidence in the literature and most of the current epidemiological data on barodontalgia has been compiled from military aircrew. The aim of this study was to evaluate the frequency of barodontalgia in French military and civilian aircrew. METHODS: A cross-sectional study was conducted in 2010. The pilots and crewmembers attending 10 medical units of the French Air Force and Navy, and 5 dedicated to civilian pilots and aircrew were given a standardized and anonymous questionnaire to complete regarding demographic and professional characteristics as well as their barodontalgia. RESULTS: Out of the 1475 questionnaires distributed, 1184 responded (response rate of 80.3%), and 6.6% of these participants (N = 74) reported at least one event of barodontalgia during their career (95% CI: 5.1-8.1%); 43 (6.8%) from the air force and 31 (6.5%) from a civilian service. Median pain intensity during barodontalgia was evaluated at 5.5 out of 10. Pain appeared most commonly during descent (47.3%) and was more frequent below 8000 m. In 10 cases (13.5%), the pilots reported that barodontalgia could have compromised flight security. DISCUSSION: Despite the improvement of aeronautical equipment and the quality of dental care, barodontalgias were still present in 2010 in the French military and in civilian aircrews. We recommend prevention programs be established in order to minimize the frequency of barodontalgias and their potential repercussions on flight safety.

Association between Dental Scores and Saliva Uremic Toxins.

Dental health is frequently altered in patients with chronic kidney disease. We conducted a prospective study on dental health in CKD patients with a specific interest in the association between dental health issues and the accumulation of uremic toxins in the saliva. A total of 88 patients were included in the study, with chronic kidney disease stage 2 to 5 (without kidney replacement). We analysed the total concentrations of eight uremic toxins (trimethylamine N-oxide -TMAO-, Indoxyl Sulfate, P-cresyl-sulfate, Indole 3-acetic acid, 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid -CMPF-, Kynurenine, Hippuric acid and Phenylacetylglutamine) and three precursors of uremic toxins (Tyrosine, Phenylalanine and Tryptophan) in the saliva using LC-MS/MS. We observed, for the first time, the association between various dental scores: DMFT, FST, CPITN, and OHIS, and saliva uremic toxins and precursors: TMAO, indoxyl sulfate, or hippuric acid. Further prospective interventional studies are required to confirm our results.

Development of Novel Polysaccharide Membranes for Guided Bone Regeneration: In Vitro and In Vivo Evaluations.

INTRODUCTION: Guided bone regeneration (GBR) procedures require selecting suitable membranes for oral surgery. Pullulan and/or dextran-based polysaccharide materials have shown encouraging results in bone regeneration as bone substitutes but have not been used to produce barrier membranes. The present study aimed to develop and characterize pullulan/dextran-derived membranes for GBR. MATERIALS AND METHODS: Two pullulan/dextran-based membranes, containing or not hydroxyapatite (HA) particles, were developed. In vitro, cytotoxicity evaluation was performed using human bone marrow mesenchymal stem cells (hBMSCs). Biocompatibility was assessed on rats in a subcutaneous model for up to 16 weeks. In vivo, rat femoral defects were created on 36 rats to compare the two pullulan/dextran-based membranes with a commercial collagen membrane (Bio-Gide®). Bone repair was assessed radiologically and histologically. RESULTS: Both polysaccharide membranes demonstrated cytocompatibility and biocompatibility. Micro-computed tomography (micro-CT) analyses at two weeks revealed that the HA-containing membrane promoted a significant increase in bone formation compared to Bio-Gide®. At one month, similar effects were observed among the three membranes in terms of bone regeneration. CONCLUSION: The developed pullulan/dextran-based membranes evidenced biocompatibility without interfering with bone regeneration and maturation. The HA-containing membrane, which facilitated early bone regeneration and offered adequate mechanical support, showed promising potential for GBR procedures.

Accuracy of commercial 3D printers for the fabrication of surgical guides in dental implantology.

OBJECTIVES: To evaluate the accuracy of two different surgical guides (small extent = single implant and large extent = full arch) fabricated by five additive manufacturing technologies (SLA=Stereolithography, DLP= Digital Light Processing, FDM=Fused Deposition Modeling, SLS=Selective Laser Sintering, Inkjet). METHODS: Overall, 72 guides (6 per type) were obtained with the different machines (SLA=Form2; DLP=Rapid Shape D40 and Cara Print 4.0; FDM=Raise 3D Pro2; SLS=Prodways P1000; Polyjet®=Stratasys J750). The guides were surface-scanned with an optical dental scanner, and the resulting files were compared with the initial design files using a surface matching software. Root Mean Square (RMS) and standard deviation were calculated, representing respectively trueness and precision. Kruskall-Wallis non-parametric test was used to compare trueness and precision between small-extent and large-extent guides and 3D printer by pairs. The threshold for significance was α=0.05, except for the comparison of printers by pairs where a Bonferroni-corrected level of 0.0033 was used. RESULTS: Significant differences were observed for trueness and precision between small-extent and large-extent guides, regardless the printer except for DLP (trueness and precision) and SLS (precision). SLA, DLP and Polyjet® technologies showed similar results in terms of trueness and precision for both small-extend and large-extend guides (P>0.05). CONCLUSIONS: The size affected the accuracy of CAD-CAM surgical guides. The different additive manufacturing technologies had a limited impact on the accuracy. CLINICAL SIGNIFICANCE: This study is of clinical interest as it shows that the 3D printing technology (SLA/DLP) has a limited impact on 3D printed surgical guides accuracy. However, the size of the guide can have a significant impact, as small-extent guides were more accurate than large-extent guides.

Malignant Transformation Rate of Oral Submucous Fibrosis: A Systematic Review and Meta-Analysis.

Oral submucous fibrosis (OSF) is a chronic progressive condition affecting the oral cavity, oropharynx and upper third of the oesophagus. It is a potentially malignant disorder. The authors collated and analysed the existing literature to establish the overall malignant transformation rate (MTR). A retrospective analysis of medical and dental scientific literature using online indexed databases was conducted for the period 1956 to 2021. The quality of the enrolled studies was assessed by the Newcastle-Ottawa Scale (NOS). A meta-analysis using a random effects model of a single proportion was performed along with statistical tests for heterogeneity. The overall proportion of malignancy across all studies was 0.06 (95% CI, 0.02-0.10), indicating an overall 6% risk of malignant transformation across all studies and cohorts. Sub-group analyses revealed strong differences in proportion of malignancy according to ethnicity/cohort; Chinese = 0.02 (95% CI 0.01-0.02), Taiwanese = 0.06 (95% CI, 0.03-0.10), Indian = 0.08 (95% CI, 0.03-0.14) and Pakistani = 0.27 (95% CI 0.25-0.29). Overall, the MTR was 6%; however, wide heterogeneity of the included studies was noted. Geographic variations in MTR were noted but were not statistically significant. Further studies are required to analyse the difference between cohort groups.

Chorion and amnion/chorion membranes in oral and periodontal surgery: A systematic review.

The aim of this study was to perform a systematic review on the clinical applications where chorion membrane (CM) and amnion/chorion membrane (ACM) were used for oral tissue regeneration procedures. Selection of articles was carried out by two evaluators in Pubmed and Scopus databases, and Outcomes (PICO) method was used to select the relevant articles. Clinical studies reporting the use of CM or ACM for oral soft and hard tissue regeneration were included. The research involved 21 studies conducted on 375 human patients. Seven clinical applications of CM and ACM in oral and periodontal surgery were identified: gingival recession treatment, intrabony and furcation defect treatment, alveolar ridge preservation, keratinized gum width augmentation around dental implants, maxillary sinus membrane repair, and large bone defect reconstruction. CM and ACM were compared to negative controls (conventional surgeries without membrane) or to the following materials: collagen membranes, dense polytetrafluoroethylene membranes, platelet-rich fibrin membranes, amnion membranes, and to a bone substitute. Several studies support the use of CM and ACM as an efficient alternative to current techniques for periodontal and oral soft tissue regeneration procedures. However, further studies are necessary to increase the level of evidence and especially to demonstrate their role for bone regeneration.

Applications of Human Amniotic Membrane for Tissue Engineering.

An important component of tissue engineering (TE) is the supporting matrix upon which cells and tissues grow, also known as the scaffold. Scaffolds must easily integrate with host tissue and provide an excellent environment for cell growth and differentiation. Human amniotic membrane (hAM) is considered as a surgical waste without ethical issue, so it is a highly abundant, cost-effective, and readily available biomaterial. It has biocompatibility, low immunogenicity, adequate mechanical properties (permeability, stability, elasticity, flexibility, resorbability), and good cell adhesion. It exerts anti-inflammatory, antifibrotic, and antimutagenic properties and pain-relieving effects. It is also a source of growth factors, cytokines, and hAM cells with stem cell properties. This important source for scaffolding material has been widely studied and used in various areas of tissue repair: corneal repair, chronic wound treatment, genital reconstruction, tendon repair, microvascular reconstruction, nerve repair, and intraoral reconstruction. Depending on the targeted application, hAM has been used as a simple scaffold or seeded with various types of cells that are able to grow and differentiate. Thus, this natural biomaterial offers a wide range of applications in TE applications. Here, we review hAM properties as a biocompatible and degradable scaffold. Its use strategies (i.e., alone or combined with cells, cell seeding) and its degradation rate are also presented.

Comparison of amniotic membrane versus the induced membrane for bone regeneration in long bone segmental defects using calcium phosphate cement loaded with BMP-2.

Thanks to its biological properties, the human amniotic membrane (HAM) combined with a bone substitute could be a single-step surgical alternative to the two-step Masquelet induced membrane (IM) technique for regeneration of critical bone defects. However, no study has directly compared these two membranes. We first designed a 3D-printed scaffold using calcium phosphate cement (CPC). We assessed its suitability in vitro to support human bone marrow mesenchymal stromal cells (hBMSCs) attachment and osteodifferentiation. We then performed a rat femoral critical size defect to compare the two-step IM technique with a single-step approach using the HAM. Five conditions were compared. Group 1 was left empty. Group 2 received the CPC scaffold loaded with rh-BMP2 (CPC/BMP2). Group 3 and 4 received the CPC/BMP2 scaffold covered with lyophilized or decellularized/lyophilized HAM. Group 5 underwent a two- step induced membrane procedure with insertion of a polymethylmethacrylate (PMMA) spacer followed by, after 4 weeks, its replacement with the CPC/BMP2 scaffold wrapped in the IM. Micro-CT and histomorphometric analysis were performed after six weeks. Results showed that the CPC scaffold supported the proliferation and osteodifferentiation of hBMSCs in vitro. In vivo, the CPC/BMP2 scaffold very efficiently induced bone formation and led to satisfactory healing of the femoral defect, in a single-step, without autograft or the need for any membrane covering. In this study, there was no difference between the two-step induced membrane procedure and a single step approach. However, the results indicated that none of the tested membranes further enhanced bone healing compared to the CPC/BMP2 group.

Bone regeneration in both small and large preclinical bone defect models using an injectable polymer-based substitute containing hydroxyapatite and reconstituted with saline or autologous blood.

Microbeads consisting of pullulan and dextran supplemented with hydroxyapatite have recently been developed for bone tissue engineering applications. Here, we evaluate the bone formation in two different preclinical models after injection of microbeads reconstituted with either saline buffer or autologous blood. Addition of saline solution or autologous blood to dried microbeads packaged into syringes allowed an easy injection. In the first rat bone defect model performed in the femoral condyle, microcomputed tomography performed after 30 and 60 days revealed an important mineralization process occurring around and within the core of the microbeads in both conditions. Bone volume/total volume measurements revealed no significant differences between the saline solution and the autologous blood groups. Histologically, osteoid tissue was evidenced around and in contact of the microbeads in both conditions. Using the sinus lift model performed in sheep, cone beam computed tomography revealed an important mineralization inside the sinus cavity for both groups after 3 months of implantation. Representative Masson trichrome staining images showed that bone formation occurs at the periphery and inside the microbeads in both conditions. Quantitative evaluation of the new bone formation displayed no significant differences between groups. In conclusion, reconstitution of microbeads with autologous blood did not enhance the regenerative capacity of these microbeads compared to the saline buffer group. This study is of particular interest for clinical applications in oral and maxillofacial surgery.

Development and characterization of a PLGA-HA composite material to fabricate 3D-printed scaffolds for bone tissue engineering.

Additive manufacturing is a rising field in bone tissue engineering. Additive fabrication offers reproducibility, high precision and rapid manufacture of custom patient-specific scaffolds. The development of appropriate composite materials for biomedical applications is critical to reach clinical application of these novel biomaterials. In this work, medical grade poly(lactic-co-glycolic) acid (PLGA) was mixed with hydroxyapatite nanoparticles (nHA) to fabricate 3D porous scaffolds by Fused Deposition Modeling. We have first confirmed that the composite material could be printed in a reproductive manner. Physical characterization demonstrated a low degradation of the material during manufacturing steps and an expected loading and homogeneous distribution of nHA. In vitro biodegradation of the scaffolds showed modifications of morphological and physicochemical properties over time. The composite scaffolds were biocompatible and high cell viability was observed in vitro, as well as a maintain of cell proliferation. As expected, the addition of nHA displayed a positive impact on osteodifferentiation in vitro. Furthermore, a limited inflammatory reaction was observed after subcutaneous implantation of the materials in the rat. Overall, this study suggests that this composite material is suitable for bone tissue engineering applications.

3D printed bone models in oral and cranio-maxillofacial surgery: a systematic review.

AIM: This systematic review aimed to evaluate the use of three-dimensional (3D) printed bone models for training, simulating and/or planning interventions in oral and cranio-maxillofacial surgery. MATERIALS AND METHODS: A systematic search was conducted using PubMed® and SCOPUS® databases, up to March 10, 2019, by following the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) protocol. Study selection, quality assessment (modified Critical Appraisal Skills Program tool) and data extraction were performed by two independent reviewers. All original full papers written in English/French/Italian and dealing with the fabrication of 3D printed models of head bone structures, designed from 3D radiological data were included. Multiple parameters and data were investigated, such as author's purpose, data acquisition systems, printing technologies and materials, accuracy, haptic feedback, variations in treatment time, differences in clinical outcomes, costs, production time and cost-effectiveness. RESULTS: Among the 1157 retrieved abstracts, only 69 met the inclusion criteria. 3D printed bone models were mainly used as training or simulation models for tumor removal, or bone reconstruction. Material jetting printers showed best performance but the highest cost. Stereolithographic, laser sintering and binder jetting printers allowed to create accurate models with adequate haptic feedback. The cheap fused deposition modeling printers exhibited satisfactory results for creating training models. CONCLUSION: Patient-specific 3D printed models are known to be useful surgical and educational tools. Faced with the large diversity of software, printing technologies and materials, the clinical team should invest in a 3D printer specifically adapted to the final application.

Correction to: 3D printed bone models in oral and craniomaxillofacial surgery: a systematic review.

An amendment to this paper has been published and can be accessed via the original article.