With the development of computer-aided surgery and rapid prototyping via 3D printing technology, digital surgery has rapidly advanced in clinical practice, especially in the field of oral and maxillofacial surgery. 3D printing technology has been applied to the functional restoration and reconstruction of the jawbone. Before surgery, a 3D digital model is constructed through software to plan the scope of the osteotomy, shape the bone graft and plan the placement of the implant. Additionally, 3D models of personalized surgical instrument guides are printed prior to surgery. With these 3D-printed models and guides, accurate excision of the jaw tumor, accurate placement of the grafted bone and precise placement of implants can be achieved during surgery. Postoperative evaluation of accuracy and function shows that 3D printing technology can aid in achieving the biomechanical goals of simultaneous implant placement in jaw reconstruction, and in combination with dental implant restoration, the technology can improve patients' postoperative occlusal and masticatory functions. Nevertheless, 3D printing technology still has limitations, such as time-consuming preparation before surgery. In the future, further development of 3D printing technology, optimization of surgical plans, and alternative biological materials are needed. Based on domestic and foreign literature and our research results, we have reviewed the process and clinical application prospects of jaw reconstruction via 3D printing technology to provide a reference for oral and maxillofacial surgeons.
Objective To explore the effects of red LED light mediated by the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (KEAP1-NRF2/HO-1) pathway on osteogenic differentiation and oxidative stress damage of human periodontal ligament stem cells (hPDLSCs) induced by high glucose, which provides a basis for the application of red light-emitting diode (LED) light in cell antioxidative damage. Methods hPDLSCs were identified by flow cytometric analysis, alkaline phosphatase (ALP) staining and Alizarin red-S staining; hPDLSCs were pretreated in a high glucose environment for 48 hours and irradiated with 1, 3, or 5 J/cm2 red LED light. A CCK-8 assay was performed to choose the radiant exposure that had the strongest effect on promoting the cell proliferation rate for subsequent experiments. hPDLSCs were divided into a control group, a high glucose group and a high glucose+light exposure group. ALP staining, ALP activity, Alizarin red-S staining and quantitative calcified nodules were used to detect the osteogenic differentiation of hPDLSCs; qRT-PCR and Western blot were used to detect the gene and protein expression levels of ALP, runt-related transcription factor 2 (RUNX2) and osterix (OSX); the relative mRNA expression levels of antioxidant enzyme-related genes superoxide dismutase 2 (SOD2) and catalase (CAT) in hPDLSCs were detected by qRT-PCR; reactive oxygen species (ROS) levels were detected by fluorescence microscopy and flow cytometry; the tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels in cell supernatants were detected by ELISA; the NRF2-specific inhibitor ML385 was used to inhibit the NRF2 pathway; ALP staining and ALP activity were used to detect the markers of early osteogenic differentiation; qRT-PCR was used to detect the gene expression of ALP, RUNX2 and OSX; and the protein expression levels of KEAP1, NRF2 and HO-1 were detected by Western blot. Results Identified, and irradiant exposure of 5 J/cm2 was chosen for subsequent experiments. Red LED light irradiation (5 J/cm2) improved the osteogenic differentiation of hPDLSCs induced by high glucose (P<0.05), increased the mRNA and protein levels of ALP, RUNX2 and OSX (P<0.05), upregulated the mRNA expression levels of SOD2 and CAT (P<0.05), reduced the levels of ROS (P<0.05), and reduced TNF-α and IL-1β levels in the cell supernatants (P<0.05). When ML385 was added to inhibit the NRF2 pathway, the ALP activity of cells was decreased (P<0.05); the gene expression levels of ALP, RUNX2 and OSX were downregulated (P<0.05); the protein level of KEAP1 was upregulated (P<0.05); and the protein levels of NRF2 and HO-1 were downregulated (P<0.05). Conclusion Red LED light may promote the proliferation and osteoblastic differentiation of hPDLSCs induced by high glucose through the KEAP1-NRF2/HO-1 pathway and reduce the oxidative stress damage to hPDLSCs induced by high glucose.
Objective To investigate the effect of isoprene cysteine carboxymethyltransferase (ICMT) gene on the migration and invasion of salivary adenoid cystic cancer cells (SACC) and the related mechanism, to provide experimental evidence for molecular targeted therapy of SACC. Methods Adenoid cystic cancer cells SACC-LM and SACC-83 were cultured in vitro, and siRNA was transfected into human SACC-LM and SACC-83 cells (experimental group) by transient transfection of a liposome vector. A blank control group and negative control group were set up respectively (transfected NC-siRNA). qRT-PCR was peformed to measure the mRNA expression of ICMT and RhoA in each group after transfection and to determine the silencing efficiency. The expression of ICMT, membrane RhoA, total RhoA, matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and Rho associated with coiled helical binding protein kinase 1 (ROCK1) in each group was detected by Western blot. The proliferation abilityies of SACC cells was detected by CCK-8 assay. The migration and invasion ability of SACC cells were detected by comparing the relative healing area of cell scratch assay and the number of Transwell assay cells. Results After transfection of ICMT-siRNA into SACC-LM and SACC-83 cells, the expression of ICMT gene and protein in the experimental group was significantly decreased compared with the negative control group and blank control group (P<0.05), but there were no significant differences in the expression of RhoA gene and total protein among all groups (P>0.05). The expression of RhoA membrane proteins, ROCK1, MMP-2, MMP-9 in the experimental group was significantly decreased compared with that in the negative control group and blank control group (P<0.05). Cell proliferation ability was significantly decreased (P<0.05). The migration and invasion abilities were significantly decreased (P<0.05). Conclusion In vitro silencing of ICMT gene can effectively inhibit the migration and invasion of human SACC-LM and SACC-83 cells, and the mechanism may be related to RhoA-ROCK signaling pathway.
Objective To investigate the application of indocyanine green in near-infrared fluorescence imaging to determine the scope of necrotic bone resection in osteoradionecrosis of the jaw and to provide a reference for clinicians. Methods Eight patients with osteoradionecrosis of the jaws were enrolled. Indocyanine green was intravenously injected through the elbow vein 10 minutes before osteotomy. After conservative resection of necrotic bone lesions based on imaging results, the scope of potential dead bone resection in the area of low fluorescence intensity was gradually expanded at an initial distance of 0.3 cm. Near-infrared fluorescence imaging and fluorescence intensity determination of bone cross-section were performed before and after extended resection. Statistical differences were analyzed. All patients with osteonecrosis underwent regular follow-up to evaluate the postoperative efficacy. Results Indocyanine green was injected into all 8 patients with osteoradionecrosis for near-infrared fluorescence imaging and the scans were clear; the fluorescence intensity of fresh bone wounds with an expanded mandibular resection range of (0.95 ± 0.14) cm was (226.2 ± 15.8) au, which was higher than that based on intraoperative macroscopic observation and radiological results (108.8 ± 3.4) au, (t = 20.718, P<0.001). The postoperative follow-up improvement rate of 8 patients was 87.5%. Conclusion Near-infrared fluorescence imaging with indocyanine green can assist in the successful removal of necrotic bone until fresh bleeding of the jaw wound occurs, which has important clinical value in defining the resection range of osteoradionecrosis of the jaw.
Objective To investigate the application value of 3D microscope in vascular anastomosis in oral and maxillofacial surgery, to provide a reference for clinicians. Methods Eighty-seven cases of free flap reconstruction in oral and maxillofacial surgery were retrospectively included, including 30 cases in the 3D microscope group and 57 cases in the optical microscope group. The differences in intraoperative vascular anastomosis time, postoperative flap survival rate and doctor evaluation scores between the 3D microscope group and the optical microscope group were compared and statistically analyzed, and the feasibility of using three-dimensional microscope in surgery was evaluated. Results The arterial anastomosis time was (26.53±3.83) min/root in the 3D microscope group and (24.88 ± 2.97) min/root in the optical microscope group, and the difference was statistically significant (P<0.05). The venous anastomosis time was (30.68 ± 3.51) min/root in the three-dimensional microscope group and (28.70 ± 2.91) min/root in the optical microscope group, and the difference was statistically significant (P<0.05). There was no significant difference in the survival rate of flaps between the 3D microscope group (n = 28, 93.33%) and the optical microscope group (n = 53, 92.98%) (P>0.05). The doctor's evaluation scores of visual fatigue, training and learning, operative difficulty index, image sharing in the three-dimensional microscope group were higher than those in the optical microscope group, and the differences were statistically significant (P<0.05). Conclusion 3D microscope has good reliability and safety in surgery, a strong sense of three-dimensionality, and the convenience of teaching and training. It can be well applied to vascular anastomosis in oral and maxillofacial surgery.
Objective To study the clinical efficacy of biological ceramics (iRoot BP Plus ) and mineral trioxide aggregate (MTA) in direct pulp capping of mature permanent teeth, to provide referrence for clinical application. Methods Seventy-four patients with pulp exposure due to deep caries or reversible pulpitis in 75 mature permanent teeth were selected and were randomly divided into two groups. iRoot BP Plus were used as pulp capping agents in the treatment group and MTA were used as pulp capping agents in the control group respectively. The clinical efficacy and imaging analysis were performed at 1, 3, 6 and 12 months after operation. Treatment success rate of the two groups were calculated, and the influence of various factors including gender, age, tooth position, cavity, number and size of pulp exposure on the efficacy of direct pulp capping were analyzed. Results Sixty patients with 61 mature permanent teeth were selected. Twelve mouths after treatment, 61 teeth of 60 patents were completely investigated (iRoot group: 31 teeth 30 patients; MTA group: 30 teeth 30 patients). The success rates of the 2 groups were 90.3% (iRoot BP Plus) and 90.0% (MTA), respectively. There was no statistical difference between 2 groups (P>0.05). Statistical analysis also showed that gender, age, tooth position, cavity, number and size of pulp exposure had no significant difference between the two groups (P>0.05). Conclusion Both iRoot BP Plus and MTA are effective in direct pulp capping of mature permanent teeth with carious pulp exposure, while the operation of iRoot is simple and convenient.
Objective To explore the trajectory of the development of permanent caries in 12- to 16-year-old students in Liuyang and to provide a reference for the prevention and management of caries. Methods Primary and secondary school students who were registered within the Liuyang jurisdiction were screened for caries from September to November by the Liuyang Center for Disease Control and Prevention. A total of 7 297 students between the ages of 12 and 16 years with complete permanent dentition caries monitoring records and traceable deciduous dentition caries monitoring records were selected from 2013 to 2019, and a zero-inflated negative binomial-latent class growth model (ZINB-LCGM) was established to describe the trajectory of the development of individual caries using the decayed missing filled teeth (DMFT) indicators. Results DMFT of 12- to 16-year-old students in Liuyang were mainly decayed teeth (DT), with the majority occurring in the first permanent molar. According to the ZINB-LCGM model, the students were classified into three latent categories, "slow growth pattern" (28.55%), "rapid growth pattern" (6.59%), and "stable pattern" (64.86%), which followed different nonlinear caries growth trajectories. Females with deciduous teeth caries were more likely to have trajectories showing a “rapid growth pattern” and a “slow growth pattern”. There were significant differences in the trajectories between men and women, as well as between those with and without primary dentition caries. Conclusion The trajectory of the development of caries in 12-16-year-old students shows heterogeneity in terms of different developmental patterns of latent categories, suggesting that females with deciduous dental caries should receive more attention.
Antimicrobial peptides have antibacterial effects on various pathogenic microorganisms, including natural antimicrobial peptides and synthetic antimicrobial peptides. According to the structure of natural antimicrobial peptides, synthetic antimicrobial peptides can be obtained by recombining different functional domains, adjusting the original amino acid sequence, or completely redesigning the peptides from scratch. Antimicrobial peptides can inhibit the growth of various cariogenic microorganisms and the formation of microbial biofilms. They also reduce acid production and acid resistance of microorganisms. Natural antimicrobial peptide genes can be used as genetic susceptibility markers for predicting the development of caries, thus, showing potential applications in the prevention and treatment of dental caries. The instability of natural antimicrobial peptides and the inability to achieve targeted sustained release limit their application in the prevention and treatment of oral caries. Synthetic antimicrobial peptides can enhance their stability and the antibacterial effect. Synthetic antimicrobial peptides can also be polymerized with common oral adhesives to reduce the incidence of microleakage after filling treatment for caries and to prevent the occurrence of secondary caries. The pH-sensitive antimicrobial peptides are slowly released to promote remineralization in the process of caries. However, the safety and biocompatibility of synthetic antimicrobial peptides are worse than those of natural antimicrobial peptides. Moreover, the combined effect of antibacterial peptides and anticaries drugs, such as fluoride, is still uncertain. Therefore, in this paper, we will review the design methods, application and underlying mechanisms of antimicrobial peptides to introduce novel methods and ideas for the prevention and treatment of dental caries.
Due to advances in digital technology, intraoral impressions have been increasingly used to fabricate implant restorations because of its simplicity, high efficiency, comfortableness and convenience. In clinical practice, the accuracy of intraoral impressions depends on various factors, including scanner technique, status of dentition and implants, auxiliary devices, materials and environment, which might influence its accuracy and limit its application. When applied to patients missing more teeth, its accuracy may be insufficient. It is suggested that intraoral impressions be used cautiously when there are multiple and far apart implants and that the scan body not be tightened excessively and that maintain appropriate environmental conditions. In this article, we have reviewed recent relevant literature and the factors affecting the accuracy of intraoral impressions for implant restoration.
Lack of alveolar bone height is a major challenge for dental implants. In recent years, the use of "sandwich" osteotomy to increase alveolar bone height has become a topic of discussion within the research community. In theory, "sandwich" osteotomy is a U-shaped osteotomy in the bone defect area, to preserve the blood supply of the mucoperiosteal on the lingual side and to create an artificial "four-wall bone bag" to build a favorable space for osteogenesis and to increase the height of the alveolar bone. Histological studies have shown that the osteogenesis speed of "sandwich" osteotomy is fast, and the bone is good. Sandwich osteotomy is suitable for buccal-lingual alveolar bone height defects less than 50% of the implant length or for unilateral defects more than 50% of the implant length. In the operation of "sandwich" osteotomy, the horizonal incision should be 10-12 mm below the crest of the buccal alveolar ridge. The design of the osteotomy line should ensure the height of the osteotomy block and that the mandibular canal does not sustain damage and that it fits the shape of the bone defect. There was no significant difference in the osteogenic effect of different types of bone graft materials used for "sandwich" osteotomy. The osteotomy block was rigorously fixed by a titanium plate, titanium nail, implant and other materials, and finally, the intraoperative area was tensioned and sutured. The effect of bone augmentation was evaluated and compared with other bone augmentation techniques; the evaluation showed that sandwich osteotomy was better for moderate vertical bone defects. This technique is highly sensitive and postoperative transient sensory loss is common. With advances in technology, the application of digital technology and ultrasonic bone knives, the risk of complications is greatly reduced and advances in digital osteotomy will promote apply of "sandwich" osteotomy, which will become a popularized technique for clinical alveolar bone augmentation.
It has been traditionally believed that a 1:1 cortical bone remodeling/tooth movement ratio has been preserved during orthodontic treatment for tooth movement, with the alveolar bone on the tension side growing and the alveolar bone on the pressure side resorbing to maintain the balance of the alveolar bone. However, recent studies have shown that alveolar bone loss has been found in patients who have undergone orthodontic treatment, suggesting that the alveolar bone does not change as the teeth change over time. Whether the morphology of the alveolar bone will change when the anterior teeth are moved has been the clinical focus. The changes of anterior alveolar bone in patients who have undergone tooth extraction after orthodontic treatment were summerized by literature review in this paper. The results of the review showed that the alveolar bone at the lingual/palatal root-cervical site of the anterior root is more prone to bone loss after extensive movement of the anterior teeth. With the development of imaging technology, CBCT is now more commonly used for analysis instead of two-dimensional images for measurement, as its results are more accurate. However, there are few multifactorial studies in which CBCT has been used to assess the morphological changes in the alveolar bone. The focus of future research is to compare the long-term changes in the anterior alveolar bone of patients of different ages based on three-dimensional imaging, and to study the correlation between different skeletal features, tooth movement patterns and alveolar bone remodeling.