Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder caused by mutations in the NF1 gene located at 17q11.2. Plexiform neurofibromas (PN) are one of the common clinical manifestations of NF1, known as NF1-related plexiform neurofibromas (NF1-PN). Head and neck NF1-PN account for 42.9% of all cases. Tumors grow rapidly during childhood and adolescence, and they can exhibit widespread growth, causing severe head, face, and neck deformities, organ dysfunction, and even loss of function. NF1-PN have the potential to transform into malignant peripheral nerve sheath tumors (MPNSTs), known as NF1-associated MPNST (NF1-MPNST). Histopathology is the gold standard for diagnosing NF1-PN, magnetic resonance imaging (MRI) is the preferred imaging examination for NF1-PN, and PET/CT examination is a reliable method for early detection and diagnosis of NF1-MPNST. Genetic testing plays an important role in early diagnosis of tumors, monitoring tumor progression, genetic counseling, and molecular level treatment and management of the disease. This article proposes the goals and principles for treating NF1-PN in the head and neck region. The main treatment methods currently used are surgery and medication. Surgical treatment includes surgical resection, and tissue flap repair or allogeneic transplantation of composite tissue after surgical resection. The mitogen-activated protein kinase inhibitors (MEK) inhibitor Selumetinib is an effective medication used to treat NF1-PN patients aged 3 years and older with symptoms and who are unable to undergo surgery. A Phase Ⅱb trial of mirdametinib, a small-molecule inhibitor, has been completed in adults and children, and it is considered well tolerated in both groups. CRISPR/Cas9 technology is expected to become an effective means of NF1-PN gene therapy. The treatment method of NF1-MPNST is similar to that of soft tissue sarcoma. However, the safety of complete resection of extra-large tumors, protection of important tissues and organs during surgery, effective control of intraoperative bleeding, reconstruction of soft and hard tissue defects in the head and neck; prospective, multicenter, randomized, double-blind, controlled clinical trials of MEK inhibitors, as well as the use of CRISPR/Cas9 technique for gene therapy NF1-PN, are all current challenges. This article summarizes recent advances and ongoing challenges in the treatment of head and neck NF1-PN, aiming to provide a reference for clinicians and researchers.
Objective To investigate the efficacy of magnesium-strontium co-doped hydroxyapatite mineralized collagen (MSHA/Col) in improving the bone repair microenvironment and enhancing bone regeneration capacity, providing a strategy to address the insufficient biomimetic composition and limited bioactivity of traditional hydroxyapatite mineralized collagen (HA/Col) scaffolds. Methods A high-molecular-weight polyacrylic acid-stabilized amorphous calcium magnesium strontium phosphate precursor (HPAA/ACMSP) was prepared. Its morphology and elemental distribution were characterized by high-resolution transmission electron microscopy (TEM) and energy-dispersive spectroscopy. Recombinant collagen sponge blocks were immersed in the HPAA/ACMSP mineralization solution. Magnesium-strontium co-doped hydroxyapatite was induced to deposit within collagen fibers (experimental group: MSHA/Col; control group: HA/Col). The morphological characteristics of MSHA/Col were observed using scanning electron microscopy (SEM). Its crystal structure and chemical composition were analyzed by X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The mineral phase content was evaluated by thermogravimetric analysis. The scaffold's porosity, ion release, and in vitro degradation performance were also determined. For cytological experiments, CCK-8 assay, live/dead cell staining, alkaline phosphatase staining, alizarin red S staining, RT-qPCR, and western blotting were used to evaluate the effects of the MSHA/Col scaffold on the proliferation, viability, early osteogenic differentiation activity, late mineralization capacity, and gene and protein expression levels of key osteogenic markers [runt-related transcription factor 2 (Runx2), collagen type Ⅰ (Col-Ⅰ), osteopontin (Opn), and osteocalcin (Ocn)] in mouse embryonic osteoblast precursor cells (MC3T3-E1). Results HPAA/ACMSP appeared as amorphous spherical nanoparticles under TEM, with energy spectrum analysis showing uniform distribution of carbon, oxygen, calcium, phosphorus, magnesium, and strontium elements. SEM results of MSHA/Col indicated successful complete intrafibrillar mineralization. Elemental analysis showed the mass fractions of magnesium and strontium were 0.72% (matching the magnesium content in natural bone) and 2.89%, respectively. X-ray diffraction revealed characteristic peaks of hydroxyapatite crystals (25.86°, 31°-34°). Infrared spectroscopy results showed characteristic absorption peaks for both collagen and hydroxyapatite. Thermogravimetric analysis indicated a mineral phase content of 78.29% in the material. The scaffold porosity was 91.6% ± 1.1%, close to the level of natural bone tissue. Ion release curves demonstrated sustained release behavior for both magnesium and strontium ions. The in vitro degradation rate matched the ingrowth rate of new bone tissue. Cytological experiments showed that MSHA/Col significantly promoted MC3T3-E1 cell proliferation (130% increase in activity at 72 h, P < 0.001). MSHA/Col exhibited excellent efficacy in promoting osteogenic differentiation, significantly upregulating the expression of osteogenesis-related genes and proteins (Runx2, Col-Ⅰ, Opn, Ocn) (P < 0.01). Conclusion The MSHA/Col scaffold achieves dual biomimicry of natural bone in both composition and structure, and effectively promotes osteogenic differentiation at the genetic and protein levels, breaking through the functional limitations of pure hydroxyapatite mineralized collagen. This provides a new strategy for the development of functional bone repair materials.
Objective To fabricate a hydrogel loaded with inositol hexaphosphate-zinc and preliminarily evaluate its performance in self-mineralization and osteoinduction, thereby providing a theoretical basis for the development of bone regeneration materials. Methods The hydrogel framework (designated DF0) was formed by copolymerizing methacryloyloxyethyltrimethylammonium chloride and four-armed poly(ethylene glycol) acrylate, followed by sequentially loading inositol hexaphosphate anions via electrostatic interaction and zinc ions via chelation. The hydrogel loaded only with inositol hexaphosphate anions was named DF1, while the co-loaded hydrogel was named DF2. The self-mineralization efficacy of the DF0 , DF1 and DF2 hydrogels was characterized using scanning electron microscopy, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The biocompatibility was assessed via live/dead cell staining and a CCK-8 assay. The osteoinductive capacity of the DF0 , DF1 and DF2 hydrogels on MC3T3-E1 cells was assessed via alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining. In the aforementioned cell experiments, cells cultured in standard medium served as the control group. Results The DF0, DF1, and DF2 hydrogels were successfully synthesized. Notably, DF1 and DF2 exhibited distinct self-mineralization within 6 days. Results from TEM, EDS, and SAED confirmed that the mineralization products were amorphous calcium phosphate in group DF1, and amorphous calciumzinc phosphate in group DF2. Biocompatibility tests revealed that none of the hydrogels (DF0, DF1, and DF2) adversely affected cell viability or proliferation. In osteogenic induction experiments, both ALP and ARS staining were intensified in the DF1 and DF2 groups, with the most profound staining observed in the DF2 group. Conclusion The developed inositol hexaphosphate-zinc hydrogel (DF2) demonstrates the dual capacity to generate calcium-phosphate compounds through self-mineralization while exhibiting excellent osteoinductive properties. This biocompatible, dual-promoting osteogenic hydrogel presents a novel strategy for bone regeneration.
Objective To investigate the barrier membrane fixation performance and enhanced guided bone regeneration (GBR) capability of a thermosensitive adhesive containing bioactive glass nanoparticles in order to provide a novel solution for membrane fixation during GBR procedures. Methods M2NP@BGN (methoxyethyl acrylate-co-N-isopropylacrylamide-co-protocatechuic acid@Bioactive glass nanoparticle), a thermosensitive adhesive, was synthesized via free radical polymerization by compositing methoxyethyl acrylate, N-isopropylacrylamide, and protocatechuic acid into a basic adhesive that was modified with bioactive glass nanoparticle (BGN). The successful fabrication of basic adhesive M2NP was characterized by attenuated total reflection-Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The thermosensitive adhesive M2NP@BGN (BGN concentration of 1 mg/mL) was characterized by scanning electron microscopy and a rheometer. By adjusting the BGN concentration (0.1 mg/mL, 0.5 mg/mL, 1 mg/mL, and 2 mg/mL), the adhesive and mechanical strengths were investigated with a universal testing machine. Biocompatibility was evaluated with a cell counting kit-8 assay and hemolysis test to identify the optimal formulation. The optimal material’s extract was co-cultured with mouse bone marrow mesenchymal stem cells, and its osteogenic activity was examined in vitro by quantitative real-time PCR, alkaline phosphatase, and alizarin red S staining. The rat mandibular defect model was established, filled with bone graft, and divided into 3 groups based on membrane fixation method: M2NP@BGN (BGN concentration of 1 mg/mL) fixation group (M2NP@BGN), titanium nail fixation group (Nail), and unfixed control group (Negative). Bone regeneration was analyzed after 8 weeks by micro computed tomography and histological staining. Results M2NP@BGN (BGN concentration of 1 mg/mL) was successfully synthesized and demonstrated rapid gelation under warm, humid conditions. The adhesive with a BGN concentration of 1 mg/mL exhibited the highest adhesive strength (P < 0.001) and significantly enhanced mechanical strength (P < 0.001) under 37℃ wet conditions. All formulations showed excellent biocompatibility, with cell viability > 80% and hemolysis ratio < 5%. M2NP@BGN (BGN concentration of 1 mg/mL) significantly upregulated the expression of Runx2 and Col I (P < 0.001) and enhanced the activity of osteogenic differentiation markers (P < 0.05). In the animal model, the M2NP@BGN group (BGN concentration of 1 mg/mL) achieved significantly higher bone volume fraction and better bone maturity compared to the negative and nail groups (P < 0.05). Conclusion M2NP@BGN (BGN concentration of 1 mg/mL) combines excellent wet adhesion with potent osteogenic activity, enhances the bone augmentation efficacy of membranes, and presents a novel fixation strategy with significant clinical translation potential for GBR therapy.
Objective To investigate the incidence and risk factors of open gingival embrasures (OGEs) in the incisor region after treatment with clear aligners in adult non-extraction patients and provide a reference for preventing the occurrence of an open gingival wedge gap in the incisal area after orthodontic treatment. Methods This study has been reviewed and approved by the institutional medical ethics committee, and informed consent was obtained from the patients. A total of 125 adult patients with malocclusion who completed clear aligner treatment at Hefei Stomatological Hospital from September 2022 to December 2024 were selected as the study subjects. Based on the presence or absence of OGEs in the incisor region observed in frontal intraoral photographs taken immediately after treatment completion, the patients were divided into a normal group and an OGE group. Clinical data, including intraoral photographs, digital models, and cone-beam computed tomography before and after treatment, were analyzed. Measurements such as incisor overlap and rotation, crown morphology, number of attachments, and interproximal enamel reduction (IPR) were recorded and analyzed. Results The incidence of OGEs between the maxillary and mandibular central incisors after clear aligner treatment in adult patients was 28.8% and 39.2%, respectively. No statistically significant differences were observed between the normal and OGE groups in terms of sex, Angle's classification, gingival biotype, overbite, overjet, IPR amount, age, treatment duration, tooth axis angulation, or horizontal movement distance of mandibular central incisors before and after treatment (P 0.05). However, significant differences were found in the number of attachments, anteroposterior distance between mesial incisal angles, distance from the interproximal contact point (ICP) to the alveolar bone crest (ABC) (ICP-ABC), horizontal distance between mesial cementoenamel junction (CEJ) of two adjacent central incisors (CEJ-CEJ) and labial alveolar bone thickness (P 0.05). IPR amount and mandibular incisor intrusion were significantly associated with the severity of OGEs (P 0.05). Regression analysis revealed that the number of attachments, anteroposterior distance between mesial incisal angles, ICP-ABC distance, and CEJ-CEJ horizontal distance were significantly correlated with the occurrence of OGEs. Conclusion The incidence of open gingival embrasures in the mandibular central incisor region is relatively high among adult patients treated with clear aligners. The number of attachments (n = 2), the anteroposterior distance between the mesio-incisal angles, the distance from the tooth contact point to the alveolar bone crest, and the horizontal distance between adjacent cementoenamel junctions have been identified as risk factors for the development of open gingival embrasures upon completion of orthodontic treatment.
Objective To summarize the circumstances of rescue events in hospitalized patients after radiotherapy for head and neck cancer in order to provide a reference for clinical decision-making. Methods This study was approved by the hospital's medical ethics committee. A retrospective analysis was conducted on the clinical data of 86 hospitalized patients admitted between 2015 and 2023 for oral and maxillofacial diseases following radiotherapy for head and neck cancer. Based on the occurrence of rescue events, patients were divided into a rescue group (n=20) and a non-rescue group (n=66). In addition, 20 healthy subjects matched for age and gender with the rescue group were included as a control group. First, baseline characteristics were compared between the rescue and non-rescue groups. Second, a descriptive analysis of the clinical characteristics and rescue events of the rescue group patients was performed. Third, differences in laboratory inflammatory and nutritional indicators, as well as tracheostomy status, were compared between the rescue and non-rescue groups. Fourth, Dolphin Imaging software was used to measure cone beam computed tomography images of the rescue group, non-rescue group, and control group. Upper airway parameters were measured, including the sagittal and coronal diameters of the nasopharyngeal, palatopharyngeal, glossopharyngeal, and laryngopharyngeal segments. Results ① A comparison of baseline characteristics between the rescue and non-rescue groups showed no statistically significant differences in age, gender, or body mass index, but the proportion of patients with comorbid pulmonary diseases was higher in the rescue group (P<0.05). ② In the rescue group, the primary reasons for radiotherapy were nasopharyngeal carcinoma (65%) and tongue cancer (25%). The mean age was (54.75 ± 11.59) years, with a male-to-female ratio of 3:1. The main reasons for this admission included radio-osteomyelitis in the mandible (55%) and recurrence of oral and maxillofacial tumors or new primary tumors in the oral and maxillofacial region (40%). The primary reason for rescue during hospitalization was dyspnea (55%), followed by acute massive hemorrhage (15%) and cardiac arrest (15%). Rescue events occurred mostly postoperatively (65%), with a median time of occurrence at 5 days post-operatively; 30% occurred preoperatively, and 5% occurred intraoperatively. ③ Laboratory indicators and tracheostomy status: preoperative and postoperative neutrophil counts, as well as the proportion of patients undergoing tracheostomy, were higher in the rescue group compared to the non-rescue group, while postoperative albumin levels were lower (P<0.05). ④ Upper airway measurements: the coronal and sagittal diameters of the nasopharyngeal segment and the coronal diameter of the glossopharyngeal segment were smaller in both the rescue and non-rescue groups compared to the control group (P<0.001). Conclusion The data from this study indicate that hospitalized patients experiencing rescue events after radiotherapy for head and neck cancer often have comorbid pulmonary diseases or tumor recurrence/new primary tumors, and frequently present with dyspnea. They exhibit a higher inflammatory state, poorer nutritional status, a greater need for emergency airway intervention, and share a common anatomical basis for dyspnea--upper airway narrowing. Clinical attention should be fully given to high-risk patients with these characteristics.
The repair of bone defects is heavily influenced by the dynamic osteogenic microenvironment. Static scaffolds constructed by traditional 3D printing technology cannot simulate the dynamic nature of the microenvironment during bone defect repair due to the fixed structure, uncontrollable release of active factors, and difficult regeneration of blood vessels, among other factors. Breaking through the limitations of these static scaffolds and realizing the intelligent and dynamic regulation of the osteogenic microenvironment is a key scientific issue in the field of bone tissue engineering. 4D printing technology combines the dynamic responsiveness of bone restoration materials with the concept of intelligent design to regulate the micro and macro structure of scaffolds. This technology provides a new method for bone tissue engineering by responding to endogenous and exogenous stimuli and creating a better osteogenic microenvironment through functionalized design, including drug delivery and antibacterial function. However, this technology currently suffers from challenges related to dynamic response material design, insufficient precision of printing technology, and mismatches between multi-stimulus response systems, metabolic rhythms of bone tissue, and functionalized composite scaffolds. Future research should focus on the development of smart response materials with excellent dynamic responses and bioactivity, the creation of new printing technologies, and the design of personalized and precise bone repair solutions. The aim of this paper is to review the current research status of 4D printing for bone tissue engineering in terms of material types, response mechanisms, and applications to provide a theoretical basis for the development and clinical application of functional bone repair materials in the future.
Microbial infections are a prevalent challenge in the prevention and treatment of oral diseases. Antibiotic therapy faces clinical limitations due to its single-target mechanism and tendency to induce resistance with repeated use, necessitating novel antibacterial strategies. Stimuli-responsive antibacterial materials, whose antimicrobial activity can be modulated by external stimuli, offer advantages such as remote controllability, potential for localized precision treatment, and a reduced risk of inducing resistance. Among these materials, mechanical force-triggered piezoelectric materials exhibit significant antibacterial activity in the biomedical field owing to their unique piezoelectric effect, excellent stability, and good biocompatibility. Research has shown that piezoelectric materials can convert mechanical energy into electrical energy in response to external forces, which enables antibacterial effects without requiring an external power source. The underlying mechanisms primarily include direct electric field effects, generation of reactive oxygen species, and immune modulation. Preliminary applications in treating oral infections (e.g., dental caries, periodontitis, and peri-implantitis) have confirmed their stability and biocompatibility, establishing a foundation for clinical translation. However, long-term efficacy and biosafety in the complex oral microenvironment require further validation. Future research should focus on optimizing material preparation protocols to enhance antibacterial efficacy and stability, further investigating the underlying antimicrobial mechanisms, and systematically evaluating their therapeutic outcomes and safety profiles across various types of oral infections. This review summarizes the antibacterial effects, mechanisms, stability, safety, and research progress of piezoelectric materials in the stomatologic field, aiming to provide new insights for further research and application in this area.
Endodontic microsurgery (EMS) is an oral surgical procedure that utilizes the magnification and illumination provided by a microscope. Fine instruments are used to remove periapical diseased tissues, resect the root apex, and tightly seal the root canal system, aiming to promote the healing of periapical tissues and retain the affected tooth whenever possible. Precise localization and resection of the root apex have always been challenging in EMS. The application of digital technology in EMS can address many issues in traditional endodontic microsurgery. Digital technology offers advantages such as optimizing surgical planning, providing precise positioning guidance, and enhancing operational accuracy. Currently, the commonly used digital technologies in EMS include static and dynamic navigation technologies and oral surgical robots. Static navigation technology enhances surgical predictability through precise preoperative planning and guided fabrication, yet is constrained by its inability to adjust during surgery. Dynamic navigation technology excels in real-time tracking and intraoperative flexibility but demands high hand-eye coordination from surgeons and may be hindered by bulky handheld devices. Oral surgical robots reduce hand tremors and human error in surgery with their high precision, stability, and ability to adjust in real time, but their clinical applicability is limited and their cost is high. In clinical practice, tailored combinations of these technologies can be applied based on case complexity. For simple cases with well-defined anatomy, static navigation alone may suffice. For complex anatomical cases, static navigation can provide initial planning, supplemented by dynamic navigation for real-time guidance or robotic systems for high-precision execution. This paper discusses the workflow, clinical application status and advantages and limitations of these three digital technologies in EMS. The continuous development of digital technology is expected to simplify the operation process, improve the navigation accuracy, and reduce the operation cost. It is believed that with continuous improvement and optimization, these technologies will effectively break through the current bottleneck of the cost of equipment, operation complexity, and accuracy enhancement. These technologies are also expected to further expand the application boundaries, providing more minimally invasive, precise, and time-saving personalized treatment solutions for endodontic diseases.
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