Epidemiological studies have shown that abnormal glucose and lipid metabolism is associated with a variety of malignant tumors, including oral squamous cell carcinoma. In this paper, the role of abnormal glucose and lipid metabolism, especially diabetes mellitus and obesity, in the occurrence and development of oral squamous cell carcinoma and its pathogenesis are reviewed based on the research results of our group and the literature. Hyperglycemia and insulinemia in diabetes mellitus are the main mechanisms that increase the risk of cancer. Our research shows that hyperglycemia can promote the proliferation, invasion and metastasis of tongue squamous cell carcinoma through the glycolytic enzyme M2 pyruvate kinase (PKM2) and hexokinase 2 (HK2). Hyperinsulinemia can promote the proliferation, invasion and metastasis of tongue squamous cell carcinoma by activating the insulin-like growth factor signal transduction system. Obese patients are often accompanied by increased serum adipokine Chemerin (Chem). Our study shows that serum Chem concentrations in obese patients with tongue cancer are significantly higher compared with nonobese patients. Chem can regulate the proliferation, invasion and migration of tongue squamous cell carcinoma cells through the SOD2-H2O2 signaling pathway. These results provide a basis for the prevention of oral squamous cell carcinoma, provide a new iqdea for the precise treatment of oral squamous cell carcinoma, and suggest that the treatment of oral squamous cell carcinoma should also actively treat patients with diabetes and obesity.
Radioactive jaw necrosis is a serious complication of head and neck radiotherapy. This complication's main characteristics are chronic necrosis and infection, and its clinical manifestations are local pain, mouth opening re'striction, speech disorder, dysphagia, exposure of dead bone, prolonged healing of facial and neck soft tissue fistula, and even pathological fracture, which brings great pain to the patient's body and mind. Radioactive jaw necrosis has become a clinical problem in the field of medicine, specifically for maxillofacial surgery of the external head and neck. The pathogenesis of radiation-induced jaw necrosis is still unclear, but high radiotherapy dose, extraction of teeth after radio-therapy and surgical trauma are recognized as high-risk factors. The diagnosis of radiation-induced jaw necrosis needs to be combined with the patient's radiotherapy history, clinical symptoms and imaging examination. Conservative or sur-gical treatment should be selected according to its clinical classification and stages, and the prevention of radiation-in- duced jaw necrosis should be emphasized. The key points are to remove dental caries, residual roots and crowns before radiotherapy; improve radiotherapy technology; and take preventive measures against high-risk factors. In recent years, the diagnosis and treatment of radiation-induced jaw necrosis has gradually become standardized and individualized.This article reviews the progress of treatment and research on radiation-induced jaw necrosis at home and abroad in terms of its definition, etiology, risk factors, diagnosis, treatment and prevention to provide reference for clinical treat-ment.
Objective To prepare the La-doped TiO2 film on the surface of 3Y-TZP ceramics in order to observe its antibacterial properties, providing an experimental basis for the application of antibacterial zirconia ceramics in the clinic.Method A cylindrical 3Y-TZP specimen with a diameter of 20 mm and a height of 3 mm was prepared. The sol-gel method was used to prepare 1% lanthanum (La)-doped TiO2 sol, and the La-TiO2 film-3Y-TZP ceramic was prepared by dip coating on the surface of 3Y-TZP. The TiO2 thin film-3Y-TZP ceramic was prepared by adding no lanthanum nitrate solution in the same way. The surface morphology of 3Y-TZP ceramic specimens (3Y-TZP group), TiO2 thin film-3Y-TZP ceramic specimens (TiO2 film group), and La-TiO2 thin film-3Y-TZP ceramic specimens (La-TiO2 film group) was observed by scanning electron microscopy, and photocatalysis, antibacterial and cytotoxicity experiments were carried out. For the photocatalytic experiment, four specimens were randomly selected from the La-TiO2 film group and TiO2 film group to observe the degradation rate of methylene blue at different time points under sunlight. In the antimicrobial experiment, five specimens were randomly selected from the La-TiO2 film group, TiO2 film group and 3Y-TZP group. The antimicrobial activity of each group was tested using the bacteriostatic circle method, and the bacteriostatic distance of each group was compared. In the cytotoxicity experiment, three samples were randomly selected from the La-TiO2 film group, TiO2 film group and 3Y-TZP group (negative control group), and the extracts were prepared. Here, 0.064% phenol solution were served as the positive control group. Morphological observation of L-929 cells in four groups was performed after 3 d of culture. Cell viability and relative cell proliferation were measured by MTT assay.Results La-TiO2 films with uniform distribution can be prepared on a 3Y-TZP surface by the dipping-drawing method. Photocatalytic experiments showed that the degradation rate of methylene blue in the La-TiO2 film group was (41.2 ± 1.5)% in daylight for 2 hours, which was higher than that in TiO2 film group (36.5 ± 2.4)%. A significant difference was noted between the two groups (t=3.321, P=0.016). The antimicrobial experiment showed that the antimicrobial distance of La-TiO2 group was (0.34 ± 0.08) mm, which was larger than that of TiO2 group (0.12 ± 0.02) mm. No obvious antimicrobial circle was noted in 3Y-TZP group, and the antimicrobial distance of the La-TiO2 film group was larger than that of TiO2 film group (F=63.798, P < 0.001). Cytotoxicity test showed that the relative proliferation rate of cells in La-TiO2 film group was (89.5 ± 1.3)%, and the cytotoxicity rating was grade 1. Significant differences were noted among the four groups (F=68.250, P < 0.001).Conclusion The La-doped TiO2 film can improve its photocatalytic activity and enhance the antibacterial activity of 3Y-TZP without obvious cytotoxicity.
Objective To analyze the different fabrication methods and surface structure of treated dentin matrix (TDM) and demineralized dentin matrix (DDM) and their diverse function on promoting the proliferation and osteogenic differential capability of human periodontal ligament cells (hPDLCs). This study provides a preliminary basis for the treatment of periodontal bone defects with bone substitutes from teeth.Methods TDM was made from human dentin matrices and demineralized incompletely by soaking in different concentrations of ethylene diamine tetra-acetic while DDM was made of human dentin matrices and demineralized completely by soaking in a hydrochloric acid solution followed by observation via SEM. The liquid extracts of TDM and DDM were collected according to the protocol of the International Standardization Organization (ISO 10993). Then, hPDLCs were divided into the following three groups: the TDM group (liquid extracts of TDM), the DDM group (liquid extracts of DDM), the control group (a-modified eagle medium with 10% fetal bovine serum), hPDLCs were cultured with liquid extracts of TDM or DDM, or a-modified eagle medium with 10% FBS). hPDLC proliferation was detected by a Cell Counting Kit-8 (CCK-8). The alkaline phosphatase (ALP) expression and calcified nodules of hPDLCs were tested.Results TDM obtained a preferable surface structure compared to DDM due to more sufficiently exposed dentinal tubules and looser fiber bundles of the intertubular and peritubular dentin. Both TDM and DDM promoted the proliferation of hPDLCs compared with the control group, and the proliferation of hPDLCs was significantly greater in the TDM group compared to the DDM group (F = 36.480, P < 0.05). The ALP activity of hPDLCs in the TDM group was higher than the DDM group. After a 14-day osteogenic induction, Alizarin red staining mineral nodes were observed in both groups; however, the TDM group displayed more calcified nodules than the DDM group.Conclusion The advantages of TDM including the surface structure, proliferation and osteogenic differentiation of hPDLCs, are more prominent than those of DDM, suggesting that TDM is a potential promising bone graft substitute in periodontal regeneration.
Objective To compare the removal efficiency and the amounts of apically extruded debris using Twisted File (TF), Twisted File Adaptive (TFA), ProTaper, and ProTaper Next combined with ultrasonic irrigation and to provide an experimental basis for the selection of root canal instrumentation in the clinic.Methods Forty mandibular premolars were randomly divided into 4 groups (n=10 teeth per group). The canals were cut using a Twisted File, Twisted File Adaptive, ProTaper, or ProTaper Next nickel-titanium instrument. The canals were irrigated with ultrasonic irrigation. The apically extruded debris were collected in preweighted Eppendorf tubes. The amount of dental tissue removed and extruded debris were assessed with an electronic balance.Results The amount of tooth tissue removed in groups A, B, C and D was 20.5 ± 2.0 mg, 17.8 ± 4.2 mg, 20.8 ± 3.9 mg and 16.5 ± 2.2 mg, respectively. Combined with ultrasonic irrigation, the Twisted File and ProTaper had a better removal efficiency than the ProTaper Next(P < 0.05). There was no significant difference in the amount of extruded debris (χ2=4.057, P=0.255) among four groups.Conclusion The Twisted File and ProTaper had a better removal efficiency than the ProTaper Next combined with ultrasonic irrigation. There was no significant difference in the amount of extruded debris using four Nickel-titanium instruments combined with ultrasonic irrigation.
Objective To investigate the three-dimensional morphological characteristics of the upper airway in children and adolescents with skeletal class Ⅲ malformation and to explore the relationship between craniofacial structure and upper airway morphology.Methods Ninety cases of malocclusion aged 3-18 years were collected. In addition, 45 cases of type I and type Ⅲ were classified into three age groups with 15 cases in each group: 3-6 years old, 7-12 years old and 13-18 years old. CBCT was taken, and the scanning data of CBCT were reconstructed by the third-party software Invivo 5. The volume, minimum cross-sectional area, height and the ratio of sagittal diameter to transverse diameter at the minimum cross-sectional area of each segment of the upper airway were measured. The difference of the upper airway between skeletal class I and skeletal class Ⅲ in each age group was analyzed and compared by group t test.Results No significant differences in the upper airway indexes were noted between skeletal class I and skeletal class Ⅲ(P > 0.05) in the 3-6 years old group. In the 7-12 years old group, the total volume of skeletal class Ⅲ upper airway (16.25 ± 3.69 cm 3), nasopharyngeal segment (2.39 ± 0.90 cm 3), and palatopharyngeal segment (5.24 ± 1.14 cm 3) were reduced compared with the total volume of the skeletal class I upper airway (20.98 ± 6.25 cm 3) , nasopharyngeal segment (4.21 ± 1.09 cm 3), and palatopharyngeal segment (8.18 ± 2.02 cm 3), respectively, the differences were statistically significant (tVtotal=2.526, tVnose=4.999, tVpalate=4.908, P < 0.05). In the 13-18 years old group, only nasopharyngeal segment volume (3.83 ± 0.90 cm 3) was reduced in skeletal type I (4.69 ± 1.34 cm 3); the difference was statistically significant (t=2.053, P < 0.05).Conclusion Age is an important factor affecting the morphology and structure of upper airway in skeletal Ⅲ malocclusion.
Objective To analyze the initial displacement of the upper central incisor and stress distribution of periodontal ligament under different torque values of upper incisors under the action of a four-curved auxiliary arch to provide a reliable basis for the safety of clinical application of four-curved auxiliary arches.Methods A three-dimensional finite element model for torque control of upper anterior teeth with a homemade quadrilateral auxiliary arch was established. Four different states were analyzed: molar ligation without extraction space (group A), microimplant ligation without extraction space (group B), molar recovery with extraction space closure (group C) (the adductive traction force was set at 115 g) and microimplant recovery with extraction space closure (group D) (the adductive traction force was set at 115 g). When four types of torque (0.5 N, 1.0 N, 1.5 N, and 2.0 N) were applied. The initial displacement of upper central incisors and the stress distribution of periodontal ligament in 16 groups (A1-A4, B1-B4, C1-C4, D1-D4) were observed.Results Under different conditions, as the strength of the four-curve auxiliary arch increases, the maxillary anterior teeth has crown labial inclination and a root lingual inclination. The displacement of the incisor tip increases with the increase in the loading force of the torque auxiliary arch, and the displacement of the incisor root apex increases as the force increases. The difference in incisor-apex displacement distance in A1-A4, B1-B4, C1-C4, D2 and D4 groups increased as the torque force increases, while the difference between the D3 group and D1 and D2 groups decreased slightly. The stress of the cervical periodontal ligament of the upper central incisor did not exceed the stress of the periodontal ligament in the following groups: A1, A2, B1, B2, B3, C1, C2, D1, and D2. The stress of the lip side of the upper central incisor did exceed the stress of the periodontal ligament in the following groups: A3, A4, B4, C3, C4, D3, and D4. In other words, when using the four-curved auxiliary arch as an implant anchorage, the force applied in the absence of extraction space should not exceed 1.5 N, and the force applied in the adduction of extraction space should not exceed 1.0 N. When using the nonimplant anchorage, the force applied in the absence of extraction space and the adduction of extraction space should not exceed 1.0 N. In addition, the range of force should not exceed the maximum stress of the periodontal ligament in the cervical region such that the effective and safe torque movement can be achieved. Under other stress conditions, the stress of the labial and cervical periodontal ligament of the upper central incisor exceeded the stress value (2.6 × 10-2MPa). The stress value of periodontal ligament was 2.6 × 10-2MPa in all groups.Conclusion A four-curved auxiliary arch has a significant effect on the upper anterior teeth, and the use of microimplants can better control root movement such that the crown of upper central incisors cannot be excessively lip inclined.
Objective To evaluate the feasibility and outcomes of the reconstruction of large anterior palatal fistulae by anteriorly based dorsal tongue flaps to provide a rational reference of anteriorly based dorsal tongue flaps for clinicians.Methods Five patients with anterior hernia had a defect range of 1.0 cm × 1.0 cm to 1.5 cm × 2.0 cm, and the anterior tongue was 1.3 cm × 3.5 cm to 2.0 cm × 3.5 cm. The defects were all repaired with anteriorly based dorsal tongue flaps. The clinical efficacy was evaluated after operation, including whether the mucosal flap was infected, whether there was any shedding before the pedicle, and whether there was any perforation after operation. Thereafter, patients who were satisfied with their chewing, swallowing, speech function and appearance were followed up.Results All patients underwent successful reconstruction of palatal defects by anteriorly based tongue flaps, and no case of spontaneous detachment of the tongue flap occurred. Patients with palatal fistulae were followed up for 16-28 months, and no recurrence was encountered. The operation had no effect on the speech, agitation and swallowing function of the tongue, and patients were satisfied with the appearance.Conclusion The dorsal lingual mucosal flap pedicled with the anterior tongue is a safe and reliable method for repairing large anterior palatal fistula.
How to obtain ideal regeneration of periodontal tissue remains a challenge in the clinical treatment of periodontitis. Three-dimensional printing technology is based on computer-aided design, which produces materials with specific 3D shapes by layer-by-layer superposition, and has been applied to periodontal tissue regeneration therapy, this method offers hope to achieve ideal periodontal regeneration. This article reviews the application of 3D printing technology in the field of periodontal tissue regeneration. The literature review results show that 3D printing technology can design three-dimensional structures using computer software in advance and produce materials with specific three-dimensional structures. 3D printing technology mainly includes selective laser sintering, selective laser melting, extrusion forming printing and 3D bioprinting. At present, the support materials prepared by 3D printing technology include ceramic materials, polymer materials and metals. Submaterials have been extensively studied given their high adjustability, and 3D-printed personalized titanium mesh has been applied in the clinic. Multiphase materials prepared by 3D-printing technology can regenerate periodontal tissue in animal experiments, but the effect is not good in patients with periodontitis. In addition, 3D printing of composite scaffolds for periodontal tissue regeneration need to be further studied.
Accurate positioning of brackets is a necessary condition for ideal orthodontic treatment. Traditional bracket bonding technology has certain limitations, such as long operation time and poor accuracy. Indirect bonding technology is a method that bonding brackets on the model through intraoral impression or scanning, and then the brackets are accurately bonded to the tooth crowns using a transfer tray. In this article, the progression of transfer trays and adhesive agents, the application of digital technology in indirect bonding technology, indirect bonding for invisible appliances, and the prospect of this technology are reviewed. The literature review results show that indirect bonding technology can locate the bracket accurately, the operation is simple, the patient’s experience is comfortable, and the clinical efficiency can be significantly improved, the photocurable adhesive is an ideal adhesive for indirect bonding technology. With the development of digital technology, indirect bonding technology will be able to locate the brackets with increasing accuracy, thus achieving the "digital precision movement" of the teeth. The bonding technology of invisible appliance accessories is essentially a type of indirect bonding technology, It requires indirect bonding technology and digital technology to highly fit the needs of computer design accessories for the visual tooth movement and the use of indirect bonding technology to accurately bond accessories, ultimately achieving the desired tooth movement. Indirect bonding technology will play an increasingly important role with the development of digital technology and invisible correction technology.
The aims of tooth restoration of endodontically treated teeth are to protect the remaining dental tissue; restore coronal morphology, functions and aesthetics; prevent bacterial microleakage and ensure periodontal healthy; prevent fracture of the restorations and reduce the wear from antagonist teeth. This article reviews the preservation and minimally invasive restoration of endodontically treated teeth. The results of the literature review show that tooth fracture resistance decreases after root canal treatment, the amount of remaining tooth tissue is an important factor affecting the success of root canal treatment, and the neck is the stress concentration area of tooth tissue, the traditional full crown and postcore crown have a certain amount of abrasion on the healthy neck teeth tissue, which will further reduce the bending resistance of the teeth and may cause the teeth to fracture. With the development of bonding technology, composite resin materials and ceramic materials, there are fewer molar tissues removed when resin, inlay, onlay, overlay and inlay crown are used to repair tooth defects, which can better preserve the remaining tooth tissues, especially the neck tooth tissues. After root canal treatment, only the pulp cavity of the tooth can be directly repaired by resin. When the marginal ridge is absent, minimally invasive restoration methods, such as inlay, onlay, and inlay crown, can be selected according to the number of marginal ridges removed and the thickness of the remaining dental tissue.
Interleukin-33(IL-33) is a new member of the interleukin-1 (IL-1) cytokine superfamily. It can activate mast cells, lymphocytes and macrophages to produce Th2 cytokines and plays a very important role in inflammation, infection, and autoimmune disease. The classical signal pathway of IL-33 includes the isotrimer of ST2 and interleukin-1 receptor accessory protein (IL-1 RAcP), which transduces signals into cells. The IL-33/ST2 signaling pathway affects bone metabolism by activating T and B lymphocytes. This article reviews the role of the IL-33/ST2 signaling pathway in bone metabolism. The results of a literature review showed that at present, scholars at home and abroad still dispute the role of IL-33 in bone metabolism. Some scholars believe that IL-33 can inhibit osteoclast formation, and IL-33 has been recently implicated in physiological bone remodeling. However, other scholars believe that IL-33 can promote osteoclast formation and differentiation, which leads to bone absorption. IL-33 and its signaling pathway are involved in bone metabolism of alveolar bone in periodontitis and periapical periodontitis. The specific mechanism remains unclear, and further studies are warranted.
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