Oral plaque biofilms are one of the bases for the survival and metabolism of different bacteria. With the emergence of drug-resistant bacteria due to antibiotic abuse, the prevention and treatment of plaque biofilm-associated oral diseases are becoming increasingly difficult. Although some research progress has been made in the field of biofilm formation and destruction, there is still a lack of effective clinical therapies for plaque biofilm-associated oral diseases. Metal nanoenzymes possess the physical properties of nanoparticles and exhibit catalytic activity similar to that of natural enzymes. The nanoscale size of metal nanoenzymes provides a greater specific surface area to help reactive oxygen species spread rapidly to active catalytic sites and improve the antioxidant properties of nanoenzymes. Additionally, metal nanoenzymes are easy to produce using different methods, such as electrochemical reduction, solvent thermal synthesis and microwave-assisted synthesis. Moreover, metal nanoenzymes can produce a high concentration of hydroxyl radicals, catalyze plaque biofilm degradation, lyse glucan and inhibit biofilm formation by oxidative stress reactions, as well as kill bacteria by releasing metal ions. Thus, metal nanoenzymes are expected to become a new option for the prevention and treatment of oral plaque biofilm-associated diseases. However, metal nanoenzymes can enter organisms through oral, intravenous and respiratory routes, triggering potential toxic effects such as pulmonary toxicity, hepatotoxicity and neurotoxicity. In a complex biological environment, the occurrence of metal nanoenzymes toxicity may involve multiple mechanisms, and the mechanism of action and safety need to be thoroughly investigated. In this paper, we intend to describe the research progress on metal nanoenzymes through an overview of their properties, antibacterial mechanisms, biotoxicity and applications in the prevention and treatment of oral plaque biofilm-related diseases, which may provide new ideas for the prevention and treatment of these diseases.
Objective To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model. Methods PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery. Results The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material. Conclusion PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.
Objective To investigate the effects of PssL-NAC reactive oxygen species (ROS)-responsive nanoparticles on intracellular ROS production, inflammatory factor levels, collagen production, cell function and Toll-like receptor 4 (TLR4), NF-κB nuclear factor-κB (p65) pathway protein expression in human gingival fibroblasts (HGFs) induced by Porphyromonas gingivalis-lipopolysaccharide (P.g-LPS). Methods This study was reviewed and approved by the ethics committee. PssL-NAC microspheres containing oil soluble antioxidant N-acetylcysteine (NAC) were obtained by connecting the hydrophobic end of polycaprolactone (PCL) and the hydrophilic end of polyethylene glycol (PEG) via thioketal (TK) bonds in response to ROS, and self loading in the aqueous and oil phases. After preparation of the PssL-NAC microspheres and aqueous NAC solution, successful synthesis of the nanoparticles was verified by transmission electron microscopy. Then, HGFs were exposed to P.g-LPS (0, 5, or 10 μg/mL), P.g-LPS (0, 5, or 10 μg/mL)+NAC, and P.g-LPS (0, 5, or 10 μg/mL)+PssL-NAC, and the ROS levels in the different groups were observed under confocal microscopy to determine the concentration of P.g-LPS for use in subsequent experiments. The groups were as follows: control group (no treatment), P.g-LPS group (HGFs treated with P.g-LPS), NAC group (HGFs treated with P.g-LPS and NAC), and PssL-NAC group (HGFs treated with P.g-LPS and PssL-NAC). Cell counting kit-8 (CCK-8) assays verified the biosafety of PssL-NAC. The ROS levels in the different groups were detected by DCFH-DA probes and observed via confocal microscopy. Real-time qPCR (RT-qPCR) was used to monitor the gene expression levels of the intracellular inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), collagen 1 (COL1) and collagen 3 (COL3). The effect of PssL-NAC on the migration of HGFs was observed via the scratch test. The protein expression of TLR4-NF-κB, and phosphorylated p65 (p-p65) in the TLR4-NF-κB pathway was evaluated by Western blot. Results PssL-NAC had no significant effect on HGF proliferation (P>0.05). At elevated P.g-LPS concentrations, PssL-NAC maintained intracellular ROS levels approximately twice those in the control group (P<0.001). PssL-NAC significantly decreased P.g-LPS-induced IL-6 (P<0.001) and TNF-α (P<0.001) gene expression and increased COL1 gene expression (P<0.001). After P.g-LPS stimulation, PssL-NAC restored cell migration to the control level (P>0.05) and decreased the protein expression of TLR4 (P<0.001), p65 (P = 0.006), and p-p65 (P = 0.017) in the TLR4-NF-κB pathway. Conclusion PssL-NAC maintains the appropriate intracellular ROS concentration, alleviates P.g-LPS-induced inflammation in HGFs through the TLR4-NF-κB pathway, and restores the cell functions of collagen production and migration in an inflammatory environment.
Objective To study the clinical effect of a polyetheretherketone (PEEK) bonding bridge on the loss of 3 internal incisors in patients with periodontitis. Methods This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. Thirty-eight patients with periodontitis and 3 missing central or lateral teeth were selected to undergo restoration with a PEEK bonding bridge and then returned to the hospital 3, 6, 12, and 24 months after the restoration was completed. The survival rate of the restorations was assessed by the modified USPHS/Ryge criteria. The plaque index, gingival index, periodontal probing depth and attachment loss of the abutments were recorded, and the changes in periodontal tissues after restoration were observed and compared. Results Over 24 months of clinical follow-up observation of 38 patients, only 1 patient underwent secondary bonding after partial debonding (evaluated as grade B), while bonding was successful in the other 37 cases (evaluated as grade A). The plaque index, gingival index and periodontal probing depth were significantly lower after restoration than before (P<0.05). There was no significant change in attachment loss between before and after restoration (P>0.05). Conclusion For periodontitis patients missing 3 internal incisors, short-term PEEK bonding bridge repair has good clinical efficacy.
Objective To study the effect of orthodontic traction on the roots and periodontal soft and hard tissues of buried obstructed upper incisors. Methods This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. From January 2018 to December 2022, 40 patients who underwent orthodontic traction on impacted upper incisors were selected; those whose contralateral homonymous apical foramen was not developed were placed in group A (23 cases), and those whose contralateral homonymous apical foramen was developed were placed in group B (17 cases). Software was used to measure the root length of the impacted upper incisors in groups A and B on cone beam CT (CBCT) images before and after traction and compare the changes in alveolar bone (alveolar bone width, labral bone plate thickness, and horizontal height of alveolar bone) and keratinized gingival width between each impacted upper incisor and the corresponding contralateral tooth immediately and one year after traction. Results The root length of the impacted upper incisors increased after traction compared to before traction (P<0.05). The width of the alveolar bone at the completion of traction in group A was similar to that of the contralateral homonymous tooth (P>0.05), whereas the width of the alveolar bone at the completion of traction in group B did not reach that of the contralateral homonymous tooth, with a significant difference in width (P<0.05). Neither the labial bone plate height or width in group A or B reached that of the contralateral homonymous tooth after traction (P<0.05). The keratinized gingival width on the affected side was also significantly smaller than that on the contralateral side (P<0.05), but it was increased significantly in group A at the one-year follow-up visit (P<0.05). Conclusion Tooth traction is conducive to impacted upper incisor root growth, alveolar bone reconstruction and keratinized gingival growth but cannot produce complete symmetry with respect to the contralateral side.
Objective Based on 3D printing technology, explore the precision of a perforator vessel location guide plate for fibular musculocutaneous flaps before the transplantation of fibular osteocutaneous flaps and evaluate its application effects. Methods This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. From May 2019 to October 2022, 14 patients with jaw defects who needed to undergo fibular perforator flap transplantation at the First Affiliated Hospital of Xinjiang Medical University were selected. For the seven patients in the guide plate group, CTA was combined with Mimics software to reconstruct both lower limbs, and the perforator vessel positioning guide for locating perforator vessels was designed; the two ends of the guide plate were designed as fixed ends, with the upper end fixed to the knee joint and the lower end fixed to the ankle joint, and the guide plate was fabricated by a 3D printer. For the seven patients in the control group, a conventional handheld Doppler probe was used for perforator vessel location. The average operation time, bleeding volume, recovery time, deviation of perforator vessel location, postoperative flap-related complications, postoperative donor site shape satisfaction, and lower extremity functional scale (LEFS) score were recorded. SPSS 25.0 software was used for statistical analysis. Results The average operation time, bleeding volume, recovery time, deviation of perforator vessel location and postoperative donor site shape satisfaction were significantly better in the guide plate group than in the control group (P<0.05); moreover, the differences in postoperative flap-related complications and LEFS scores were not statistically significant (P>0.05). Conclusion Based on 3D printing technology, fibular musculocutaneous flap perforator vessels can be more accurately located using a guide plate and the knee and ankle as fixed points, and this method can effectively stabilize the guide position, prevent soft tissue offset, and improve positioning accuracy and thus deserves to be generalized.
Objective To explore the treatment options for congenitally missing teeth in patients with ectodermal dysplasia and provide a clinical reference. Methods A patient with ectodermal dysplasia with a concave midface, anterior protrusion of the chin, and underdevelopment of the lower third of the face presented with congenital loss of multiple maxillary teeth, malocclusion of the remaining teeth, congenital loss of mandibular dentition, small dental arches, and upper and lower alveolar bone hypoplasia. The patient was treated by means of a removable partial maxillary prosthesis, implants in the anterior region of the lower mandible designed with the assistance of digital guides, and bar-clamped implant-overlay prostheses. A literature review of the protocol for the treatment of this condition was also conducted. Results In addition to good retention and stability after denture wear, an excellent occlusal relationship, improvement of the patient's facial appearance, including upper and lower lip fullness, more equal balancing of the lower and middle 1/3 of the face, and improved masticatory function were achieved. The results of the literature review showed that patients with ectodermal dysplasia who are congenitally edentulous usually have a complex intraoral situation that makes restoration difficult, and common restorative modalities for these patients include fixed bridges, removable partial dentures, complete dentures, overdentures, and implant prostheses, which need to be selected according to the actual intraoral situation of each patient. Currently, there is no consensus on the treatment of congenitally missing teeth in patients with ectodermal dysplasia, and some scholars have suggested that fixed restorations be recommended for patients with fewer missing teeth, while the option of removable or implant-covered denture restorations should be given to patients with more missing teeth, with removeable prostheses for underage patients that are replaced with permanent fixed prostheses when the jaws have stabilized. Conclusion In patients with ectodermal dysplasia with congenital tooth loss, all factors should be taken into account, and an individualized restorative plan should be developed.
Objective To explore the clinical manifestations, histopathological characteristics, diagnosis, treatment, and prognosis of simultaneous unilateral primary tumors of different pathological types in the parotid gland. Methods A case of simultaneous unilateral primary parotid gland tumors, i.e., adenolymphoma and basal cell adenoma, was reviewed and analyzed in combination with the literature. Results The patient discovered a lump in the right parotid gland area one month prior to presentation, and a tumor was palpated in the shallow lobe of the right parotid gland before surgery. According to MR images, the initial diagnoses were tumors of the shallow and deep lobes of the right parotid gland. The tumors of the deep and shallow lobes were excised with part of the gland, and the facial nerves were dissected under general anesthesia. Postoperative pathology revealed an adenolymphoma in the shallow lobe of the right parotid gland and a basal cell adenoma with cystic transformation in the deep lobe. The surgical effect was good, with no complications, and there was no recurrence after 1 year of follow-up. A review of the relevant literature showed that multiple primary tumors of the parotid gland can manifest as the simultaneous presence of two or more types of tumors on both sides or on one side, and the disease is mainly treated with surgery. Conclusion Multiple unilateral primary parotid gland tumors are rare. Imaging examinations need to be combined with clinical evaluations to prevent missed diagnoses. Surgery is the first treatment option, and patients with benign tumors have a good prognosis.
Magnetic fields are safe and used in noninvasive physical therapies. Numerous studies have confirmed that magnetic fields have good osteogenic effects and certain value for clinical application in accelerating orthodontic tooth movement, promoting bone-implant integration, promoting fracture healing and improving the effects of distraction osteogenesis. Magnetic fields are expected to become applied as effective auxiliary methods for treating oral diseases. To support the clinical application of magnetic fields, this article reviews the applications of magnetic fields in the oral cavity, the biological effects on bone cells and the molecular mechanisms through which magnetic fields regulate bone metabolism. The biological effects of magnetic fields on bone cells include promoting osteogenesis by osteoblasts and mesenchymal stem cells and inhibiting bone resorption by osteoclasts. At the molecular level, bone cells sense and respond to magnetic stimulation, and through various mechanisms, such as displacement currents, Lorentz forces, and free radical pair effects, stimuli are transformed into biologically recognizable electrical signals that activate complex downstream signaling pathways, such as the P2 purinergic receptor signaling pathway, adenosine receptor signaling pathway, transforming growth factor-β receptor signaling pathway, mammalian target of rapamycin (mTOR) pathway, and Notch pathway. In addition, magnetic parameters, which are the factors affecting the osteogenic effects of magnetic fields, are discussed. However, the mechanisms of the osteogenic effects of magnetic fields are unclear, and further studies of these mechanisms could provide effective strategies for bone regeneration and periodontal tissue regeneration. In addition, considering the target of magnetic field therapies, combination with other drugs could lead to new strategies for the treatment of oral diseases.
Oral submucous fibrosis (OSF) is one of the most common precancerous lesions of the oral mucosa, and its pathogenesis has not been fully elucidated. Small noncoding RNAs (SncRNAs), a class of RNA molecules that do not code for proteins, have been widely reported to be involved in the regulation of a variety of human diseases. An increasing number of studies have shown that a variety of SncRNAs play important roles in the pathogenesis of OSF. Current studies have shown that microRNAs (miRNAs) are involved in OSF disease progression by regulating the expression of related transcription factors and genes or epithelial mesenchymal transformation to regulate the activation of fibroblasts (FBs). Long noncoding RNAs (lncRNAs) that transform growth factor-β/suppressor of mothers against decapentaplegic (TGF-β/Smad) signaling pathways or interact with miRNAs are involved in the development of OSF. Circular RNAs (circRNAs) play a role in OSF by interacting with miRNAs. tRNA-derived small RNAs (tsRNAs) are involved in the progression of various fibrotic diseases, but their specific mechanism of action in OSF still needs to be further explored. In the future, it is still necessary to focus on the targets of SncRNAs mediating OSF progression and explore their function and molecular mechanism in OSF to provide new ideas for the diagnosis and treatment of OSF.
As the main means of mastication, teeth can withstand countless functional contacts. The mechanical properties of teeth are closely related to their tissue structure. Enamel and dentin have a high hardness and modulus of elasticity, and their graded structure allows them to withstand bite forces without being susceptible to fracture. When tooth tissue is defective, full crown restoration is often needed to restore the normal shape and function of the tooth. Metal materials, ceramic materials, and polyetheretherketone (PEEK) materials are commonly used for crown restoration. Metal materials have certain disadvantages in terms of aesthetics and are relatively rarely used in clinical practice. Ceramic materials with different compositions exhibit differences in performance and aesthetics, but their elastic modulus and hardness are much higher than those of dental tissue, resulting in mismatching mechanical properties. In contrast, the elastic modulus of PEEK is lower than that of tooth tissue and similar to that of bone tissue, but its properties can be improved by fiber reinforcement. Notably, when the mechanical properties of a restoration material and tooth tissue are not fully matched, the interface between them often forms a potential weak link, which ultimately affects the stability and long-term effect of the restoration. This article introduces the mechanical properties and corresponding structural characteristics of enamel and dentin. On this basis, the advantages and limitations of existing restoration materials are analyzed, and the possibility of biomimetic design of full crowns is further explored.
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