Cellularized Biomaterials Used as Gingival Connective Tissue Substitutes In Vivo: A Systematic Review.

Developing an in vitro model of gingival connective tissue that mimics the original structure and composition of gingiva for clinical grafting is relevant for personalized treatment of missing gingiva. Using tissue engineering techniques allows bypassing limitations encountered with existing solutions to increase oral soft tissue volume. This review aims to systematically analyze the different currently existing cellularized materials and technologies used to engineer gingival substitutes for in vivo applications. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. An electronic search on PubMed, Scopus, Web of Science, and Cochrane Library databases was conducted to identify suitable studies. In vivo studies about gingival substitutes and grafts containing oral cells compared with a control to investigate the graft remodeling were included. Risk of bias in the included studies was assessed using the Systematic Review Center for Laboratory animal Experimentation (SYRCLE) 10-item checklist. Out of 631 screened studies, 19 were included. Animal models were mostly rodents, and the most used implantation was subcutaneous. According to the SYRCLE tool, low-to-unclear risk of bias was prevalent. Studies checked vascularization and extracellular remodeling up to 60 days after implantation of the cellularized biomaterial. Cells used were mostly fibroblasts and stem cells from oral origin. Grafts presenting vascularization potential after implantation were produced by tissue engineering technologies including cell seeding or embedding for 14, cell sheets for 2, microsphere for 1, and extrusion 3D bioprinting for 2. Components used to build the scaffold containing the cells are all naturally derived and are mainly fibrin, gelatin, collagen, agarose, alginate, fibroin, guar gum, hyaluronic acid, and decellularized extracellular matrix. The most recurring crosslinking method was using chemicals. All studies except one reported vascularization of the graft after implantation, and some detailed extracellular matrix remodeling. Current solutions are not efficient enough. By assessing the relevant studies on the subject, this systematic review showed that a diversity of cellularized biomaterials substituting gingival connective tissue enables vascularization and extracellular remodeling. Taking the results of this review into account could help improve current bio-inks used in 3D bioprinting for in vivo applications compensating for gingival loss.

The use of digital technologies in peri-implant soft tissue augmentation - A narrative review on planning, measurements, monitoring and aesthetics.

OBJECTIVE: To identify the different uses and modalities of digital technologies to diagnose, plan and monitor peri-implant soft tissue conditions and aesthetics. METHODS: A comprehensive narrative review of pertinent literature was conducted, critically appraising key digital technologies that may assist peri-implant soft tissue augmentation and assessment. An electronic search on four databases including studies published prior to 1st July 2023 was performed and supplemented by a manual search. RESULTS: Predominantly, tools such as cone beam computed tomography (CBCT), intraoral scanning (iOS), intraoral ultrasonography and digital spectrophotometry were commonly to assess and monitor peri-implant soft tissues. The main clinical and research applications included: (i) initial assessment of mucosal thickness, supra-crestal tissue height and keratinized mucosa width, (ii) evaluation of peri-implant soft tissue health and inflammation, (iii) monitoring profilometric changes and midfacial mucosal margin stability over time and (iv) aesthetic evaluation through colour assessment. While evidence for some digital tools may be limited, the integration of digital technologies into peri-implant soft tissue management holds great promise. These technologies offer improved precision, comfort and speed in assessment, benefiting both patients and clinicians. CONCLUSION: As digital technologies progress, their full potential in peri-implant soft tissue augmentation and their value will become more evident with ongoing research. Embracing these innovations and their potential benefits is recommended to ensure that during progress in implant dentistry, patient care is not hindered.

Use of Human Gingival Fibroblasts for Pre-Vascularization Strategies in Oral Tissue Engineering.

BACKGROUND: Cocultures of human gingival fibrobasts (hGF) and endothelial cells could enhance regeneration and repair models as well as improve vascularization limitations in tissue engineering. The aim of this study was to assess if hGF could support formation of stable vessel-like networks. METHODS: Explant primary hGF were isolated from gum surgical wastes collected from healthy patients with no history of periodontitis. Human umbilical vein endothelial cells (HUVEC) were two-dimensional (2D) and three-dimensional (3D) cocultured in vitro with hGF at a cell ratio of 1:1 and medium of 1:1 of their respective media during at least 31 days. Vessel quantification of HUVEC networks was performed. In order to investigate the pericyte-like properties of hGF, the expression of perivascular markers α-SMA, NG2, CD146 and PDGFR-ß was studied using immunocytochemistry and flow cytometry on 2D cultures. RESULTS: hGF were able to support a long-lasting HUVEC network at least 31 days, even in the absence of a bioreactor with flow. As observed, HUVEC started to communicate with each other from day 7, constructing a network. Their interconnection increased significantly between day 2 and day 21 and lasted beyond the 31 days of observation. Moreover, we tried to explain the stability of the networks obtained and showed that a small population of hGF in close vicinity of HUVEC networks expressed perivascular markers. CONCLUSION: These findings highlight a new interesting property concerning hGF, accentuating their relevance in tissue engineering and periodontal regeneration. These promising results need to be confirmed using more 3D applications and in vivo testing.

Engineered Prevascularization for Oral Tissue Grafting: A Systematic Review.

Extensive dental and periodontal defects are frequent and with a limited regenerative potential. Tissue engineering could be a promising tool to obtain personalized oral grafts. However, current research shows a lack of in vitro engineered oral tissues. This is explained by the difficulty to engineer blood vessel systems, impairing the connection to the host tissue and the graft success. Various strategies were used to engineer vascularized tissues and reported successful results, thus needing a clear analysis of the current state of art in oral tissue engineering. This systematic review aimed at studying the critical factors and techniques used to engineer a prevascularized oral tissue graft. PubMed, Cochrane Library, and SCOPUS databases were searched over the last 5 years following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Out of 638 screened studies, 24 were included in the systematic review according to strict inclusion and exclusion criteria and focusing on higher connection to the host vasculature. Animal models were all rodents, and subcutaneous implantation was the most used intervention. Studies presented low-to-unclear risk of bias according to the Systematic Review Center for Laboratory Animal Experimentation tool. Endothelial cells were mainly human umbilical vein endothelial cells, while stromal cells were most of the time oral or mesenchymal stem cells. Coculture of both types of cells at a 1:1 ratio was the most common technique used to obtain vascular networks, and some studies precultured grafts up to 3 weeks to enable network formation before implantation. Prevascularized grafts were produced by various tissue engineering technologies, including cell seeding and/or embedding, cell sheets, and spheroids. All studies reported a statistically significant faster and higher connection to host of prevascularized constructs compared to controls. Vessel networks were indeed denser, with a higher portion of lumen containing erythrocytes and blood flow increased. By assessing the relevant studies on the subject, this systematic review showed that engineered prevascularization proved to be an interesting approach to improve graft connection to the host vasculature and respective specific cell and scaffold criteria. Further studies on enhanced scaffolds and larger animals seem necessary to confirm these promising results with more voluminous grafts and get closer to native human tissues and applications. Impact statement Autologous oral grafts display limitations in terms of revascularization and morbidity of donor sites, despite being the gold standard. This systematic review aimed at clarifying existing data regarding techniques to engineer prevascularized oral grafts. Tissue engineering techniques, using cocultures of endothelial and oral stromal cells, proved to be an efficient way to enhance and accelerate the connection of the graft to the host vasculature. Engineered prevascularization appears to be a promising way to improve the connection to the host and the vascularization of grafts, especially when voluminous. Large animal and human studies are necessary to allow clinical translation.

Nucleotide lipid-based hydrogel as a new biomaterial ink for biofabrication.

One of the greatest challenges in the field of biofabrication remains the discovery of suitable bioinks that satisfy physicochemical and biological requirements. Despite recent advances in tissue engineering and biofabrication, progress has been limited to the development of technologies using polymer-based materials. Here, we show that a nucleotide lipid-based hydrogel resulting from the self-assembly of nucleotide lipids can be used as a bioink for soft tissue reconstruction using injection or extrusion-based systems. To the best of our knowledge, the use of a low molecular weight hydrogel as an alternative to polymeric bioinks is a novel concept in biofabrication and 3D bioprinting. Rheological studies revealed that nucleotide lipid-based hydrogels exhibit suitable mechanical properties for biofabrication and 3D bioprinting, including i) fast gelation kinetics in a cell culture medium and ii) shear moduli and thixotropy compatible with extruded oral cell survival (human gingival fibroblasts and stem cells from the apical papilla). This polymer-free soft material is a promising candidate for a new bioink design.

Diagnosis and Management of Natal and Neonatal Teeth: Case Report of Three Newborns.

Natal and neonatal teeth are rare features that can lead to various issues, from traumatic injuries and feeding difficulties to more severe problems, such as risk of aspiration due to excessive mobility of teeth. The purpose of this paper is to discuss the diagnosis and management of natal and neonatal teeth, and describe three cases of newborns with natal teeth. Decision processes and management are detailed regarding the specificity of each case. Periodic follow-up is recommended to maintain oral health and prevent any issues related to premature loss or eruption of primary teeth. A close collaboration between pediatricians and dentists should be considered in order to allow early diagnosis and efficient treatment.

Impact of systemic sclerosis oral manifestations on patients' health-related quality of life: A systematic review.

BACKGROUND: Oropharyngeal features are frequent and often understated in the treatment clinical guidelines of systemic sclerosis in spite of important consequences on comfort, aesthetics, nutrition and daily life. The aim of this systematic review was to assess a correlation between the oropharyngeal manifestations of systemic sclerosis and patients' health-related quality of life. METHODS: A systematic search was conducted using four databases [PubMed® , Cochrane Database® , Dentistry & Oral Sciences Source® and SCOPUS® ] up to January 2018, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Grey literature and hand search were also included. Study selection, risk bias assessment (Newcastle-Ottawa scale) and data extraction were performed by two independent reviewers. The review protocol was registered on PROSPERO database with the code CRD42018085994. RESULTS: From 375 screened studies, 6 cross-sectional studies were included in the systematic review. The total number of patients included per study ranged from 84 to 178. These studies reported a statistically significant association between oropharyngeal manifestations of systemic sclerosis (mainly assessed by maximal mouth opening and the Mouth Handicap in Systemic Sclerosis Scale) and an impaired quality of life (measured by different scales). Studies were unequal concerning risk of bias mostly because of low level of evidence, different recruiting sources of samples and different scales to assess the quality of life. CONCLUSION: This systematic review demonstrates a correlation between oropharyngeal manifestations of systemic sclerosis and impaired quality of life, despite the low level of evidence of included studies. Large-scaled studies are needed to provide stronger evidence of this association.

Orofacial consequences of systemic sclerosis: A systematic review.

Orofacial involvement is common and often understated in the treatment clinical guidelines of systemic sclerosis. It impairs daily life by having repercussions on comfort, nutrition, aesthetics and self-confidence. This review aimed at describing exhaustively the different orofacial consequences of systemic sclerosis. A systematic search was conducted using four databases (PubMed, Cochrane Library, Dentistry & Oral Sciences Source and SCOPUS) up to December 2016 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses. Grey literature and hand search were also included. To be eligible for the inclusion, studies needed to meet the following criteria: randomised controlled trials, cross-sectional studies, case-control studies, pilot studies or cohort studies and full text available in English or French, with abstract. The studies had to concern at least 30 patients suffering from systemic sclerosis and having clinical and radiological oropharyngeal examination. The diagnosis of systemic sclerosis had to be determined according to precise recommendations; the retrieved oropharyngeal manifestations had to affect hard or soft tissues of the mouth and/or pharynx and needed to be evaluated with clinical measures. Study selection, risk bias assessment (Newcastle-Ottawa scale) and data extraction were performed by two independent reviewers. The retrieved features were microstomia and xerostomia associated with real hyposialia, temporomandibular joint symptoms, high caries experience, periodontal diseases as well as an increased risk of oral cavity and pharynx cancer. Early diagnosis enabling early management, prevention and oral hygiene is the key to avoid complicated and invasive procedures. Studies with higher level of evidence remain necessary to create standardised protocols.

Case Report of a Severe Recurrent Tongue Self-Injury in an Infant With Dystonia.

Dystonia is characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive movements, postures, or both that are typically patterned, twisting, and sometimes tremulous. It is often initiated or worsened by voluntary action and associated with overflow muscle activation. In this article we report a case of severe oromandibular dystonia, which is a specific form of dystonia characterized by involuntary, action-induced tonic or clonic spasms of the masticatory, lingual, and pharyngeal musculature. Episodes of repeated tongue biting in a 17-month-old girl caused her to stay in the PICU for 4 weeks. These episodes were the consequence of dystonia induced by a perinatal stroke. We highlight the specific dental management that enabled us to treat the child without extractions. Facing this type of complex illness, we insist on the importance of interdisciplinary work with the goal of avoiding outdated techniques. The use of botulinum toxin seemed relevant.