Down syndrome (DS) is the most often diagnosed chromosomal disorder in newborns. The incidence is 1:792 live births. The article describes the irregularities and characteristics found in trisomy 21, which greatly affect the functioning of the stomatognathic system. The most significant disorders include the following: false macroglossia, muscular hypotonia and gothic palate. These abnormalities affect articulation, breathing, food intake, and swallowing. We analyzed the morphological characteristics of the craniofacial region in children with DS based on the current literature review. The following databases were used for the analysis: MEDLINE (via PubMed), Scopus, Infona, and Dentistry & Oral Sciences Source. In the course of the study, 199 pieces of literature were analyzed; the analysis also included 18 articles on children and adults with DS. It also took into account the structure of the palate, dental and skeletal defects, size of the tongue, muscular hypotonia, and temporomandibular joint dysfunction. Down syndrome is still a current subject of research. Although macroglossia, hypotonia, malocclusion, and temporomandibular joint abnormalities are not features exclusive to DS, numerous dysfunctions and parafunctions as well as retarded psychomotor development greatly complicate the treatment. Therefore, interdisciplinary treatment of patients with trisomy 21 and early treatment in the first months of life with the use of the Castillo-Morales plate are very important, as they ensure better adaptation to the subsequently used apparatus and reduce the risk of disorders of the stomatognathic system.

A Chitosan is a copolymer of N-acetyl-D-glucose amine and D-glucose amine that can be easily produced. It is a polymer that is widely utilized to create nanoparticles (NPs) with specific properties for applications in a wide range of human activities. Chitosan is a substance with excellent prospects due to its antibacterial, anti-inflammatory, antifungal, haemostatic, analgesic, mucoadhesive, and osseointegrative qualities, as well as its superior film-forming capacity. Chitosan nanoparticles (NPs) serve a variety of functions in the pharmaceutical and medical fields, including dentistry. According to recent research, chitosan and its derivatives can be embedded in materials for dental adhesives, barrier membranes, bone replacement, tissue regeneration, and antibacterial agents to improve the management of oral diseases. This narrative review aims to discuss the development of chitosan-containing materials for dental and implant engineering applications, as well as the challenges and future potential. For this purpose, the PubMed database (Medline) was utilised to search for publications published less than 10 years ago. The keywords used were “chitosan coating” and “dentistry”. After carefully selecting according to these keywords, 23 articles were studied. The review concluded that chitosan is a biocompatible and bioactive material with many benefits in surgery, restorative dentistry, endodontics, prosthetics, orthodontics, and disinfection. Furthermore, despite the fact that it is a highly significant and promising coating, there is still a demand for various types of coatings. Chitosan is a semi-synthetic polysaccharide that has many medical applications because of its antimicrobial properties. This article aims to review the role of chitosan in dental implantology.

Three-dimensional (3D) printing technology has brought much innovation to medicine and has been successfully adopted in many areas of dentistry. Although 3D printing techniques are being increasingly used, their advantages and disadvantages still need to be investigated, particularly with regard to the materials used in dentistry. Dental materials should be biocompatible and non-cytotoxic, and have sufficient mechanical integrity in the oral environment in which they are intended for use. The present work aimed to identify and compare the mechanical properties of three 3D-printable resins. The materials included IBT Resin, BioMed Amber Resin and Dental LT Clear Resin. The Formlabs Form 2 printer was used. A tensile strength test was performed on 10 specimens of each resin. Tensile modulus was measured on 2-millimeter-thick dumbbell-shaped specimens, 75 mm in length and 10 mm in width. The 10 specimens of each resin were mounted between the grips of a universal testing machine (Z10-X700). The results showed that BioMed Amber specimens cracked easily, yet no deformation was observed. The amount of force used to test the tensility of the specimens was the lowest for IBT Resin, while it was the highest for Dental LT Clear Resin. IBT Resin was the weakest material, whereas Dental Clear LT Resin was the strongest.

Background: Treacher Collins Syndrome (TCS) is a rare, congenital craniofacial syndrome. Its most characteristic feature is mandibular and midface hypoplasia. Due to malformations of the facial skeleton, airway abnormalities can also be observed, predisposing individuals to obstructive sleep apnoea (OSA). OSA in TCS may contribute to significant morbidity, including developmental delays, cardiovascular disorders and reduced quality of life. Objectives: This narrative review aims to present the true prevalence of OSA and the treatment options for TCS patients. Additionally, the pathophysiology and diagnostic tools for this condition were briefly outlined. Methods: The literature search included publications from PubMed, Scopus, Web of Science and Cochrane Library. The chosen period of time for these publications was 2000–2024. Results: The results showed that OSA is a serious problem among TCS patients. Although there is no standardised treatment protocol, the primary methods often include mandibular distraction osteogenesis (MDO) and continuous positive airway pressure (CPAP). Approaches such as hypoglossal nerve stimulation (HNS) need further investigation, especially with longitudinal observations. Conclusions: The development of treatment options seems to be promising, suggesting a favourable outlook for standardising the treatment protocols.

External apical root resorption in permanent teeth is a multifactorial process influenced by a variety of local and systemic factors. This report describes a case of multiple and severe apical root resorptions in a patient with Turner syndrome. The condition was discovered in a young female with Turner syndrome after 30 months of orthodontic treatment with fixed appliance. The purpose of this report is to present reports by other authors on the potential causes of the increased risk of tooth resorption in patients with Turner syndrome and to share insights derived from its course, highlighting the implications and lessons learned. Patients with Turner syndrome are not ideal candidates for orthodontic treatment. Prior to commencing orthodontic treatment, it is essential to carefully consider the potential benefits of the therapy compared to the risk associated with exacerbating root resorption. In the case of Turner syndrome patients, where there is an elevated risk of such complications, a thorough analysis should be conducted to determine whether the expected benefits of the treatment outweigh the potential hazards to the patient’s dental health.

Background: Clear aligner therapy (CAT) is increasingly popular due to aesthetic and functional advantages. Recent advances allow direct 3D printing of aligners, raising questions about their cytotoxicity and biocompatibility under intraoral conditions. Objectives: To review and synthesize current evidence on the cytotoxicity and biocompatibility of 3D-printed and thermoformable orthodontic aligners, and to identify factors affecting cellular responses. Eligibility criteria: Original research published from 2021 to 2026 evaluating the safety of orthodontic aligners; conference abstracts, editorials, and review papers were excluded. Sources of evidence: Medline (via PubMed), Scopus, Web of Science, and the Cochrane Library; search terms “aligner” AND “biocompatibility”; last search conducted on 31 January 2026. Charting methods: Data on authors, publication year, material type, experimental model, cytotoxicity assessment (extraction solvent, incubation period, cell line, and cell exposure), and main results were extracted independently by two reviewers. Results: Fourteen in vitro studies were included, seven on thermoformable aligners and seven on directly 3D-printed aligners; no clinical trials were identified. Material composition, post-processing, and oral environmental factors influenced cytotoxicity. Some materials exhibited acceptable biocompatibility, whereas others showed varying cytotoxic effects, indicating inconsistencies across studies. Conclusions: Directly 3D-printed and thermoformable aligners show potential for safe intraoral use, but evidence is limited to in vitro studies. Further standardized in vitro and in vivo research is needed to reliably assess cytotoxicity and ensure patient safety before widespread clinical implementation.