Effect of fence tray matching care on excess adhesive and bracket placement accuracy for orthodontic bonding: an in vitro study.

OBJECTIVE: This study aimed to evaluate the effect of fence tray matching care (FTMC) in bracket bonding by measuring excess adhesive, as well as linear and angular deviations, and by comparing it with the half-wrapped tray (HWT). MATERIALS AND METHODS: An intraoral scanner was used to acquire data on the maxillary dental arch of a patient with periodontitis.Furthermore, 20 maxillary dental arch models were 3D printed. Using 3Shape, PlastyCAD software, and 3D printing technology, 10 FTMC (method I) and HWT (method II) were obtained. By preoperative preparation, intraoperative coordination, and postoperative measurement, the brackets were transferred from the trays to the 3D-printed maxillary dental arch models. Additionally, the bracket's excess adhesive as well as linear and angular deviations were measured, and the differences between the two methods were analyzed. RESULTS: Excess adhesive was observed in both methods, with FTMC showing less adhesive (P< 0.001), with a statistical difference. Furthermore, HWT's vertical, tip and torque, which was significantly greater than FTMC (P< 0.05), with no statistical difference among other respects. The study data of incisors, canines, and premolars, showed that the premolars had more adhesive residue and were more likely to have linear and angular deviations. CONCLUSIONS: The FTMC had higher bracket bonding effect in comparison to HWT, and the adhesive residue, linear and angular deviations are smaller. The fence tray offers an intuitive view of the precise bonding of the bracket, and can remove excess adhesive to prevent white spot lesions via care, providing a different bonding method for clinical applications.

FLRT2 mediates chondrogenesis of nasal septal cartilage and mandibular condyle cartilage.

Nasal septal cartilages (NSCs) and mandibular condyle cartilages (MCCs) are two important cartilages for craniomaxillofacial development. However, the role of FLRT2 in the formation of NSCs and MCCs remains undiscovered. NSCs and MCCs were used for immunocytochemistry staining of collagen II, toluidine blue staining, and alcian blue staining. Quantitative reverse transcription­PCR and western blot were used to detect mRNA and protein expressions of FLRT2, N-cadherin, collagen II, aggrecan, and SOX9. Cell proliferation of MCCs and NSCs was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell counting kit­8 assay. Cell migration of MCCs and NSCs was examined by wound healing assay and Transwell. Chondrogenesis of MCCs and NSCs were similar in morphological characteristics, while different in cell proliferation, migration, and extracellular matrix. FLRT2 promotes the proliferation and migration of NSCs. There were up-regulation of N-cadherin and down-regulation of collagen II, aggrecan, and SOX9 in NSC with knock down FLRT2. The current study, as demonstrated by Xie et al., reveals that FLRT2 overexpression in Sprague-Dawley neonatal rats promotes the proliferation and migration of NSCs and MCCs, decreases N-cadherin while increases collagen II, aggrecan, and SOX9 in NSC and MCCs. Altogether, FLRT2 mediates chondrogenesis of NSCs and MCCs.

B-cell specific Moloney murine leukemia virus insertion site 1 contributes to invasion, metastasis, and poor prognosis in salivary adenoid cystic carcinoma.

Background/purpose: Upregulation of B-cell specific Moloney murine leukemia virus insertion site 1 (BMI-1) has been involved in the invasion, metastasis, and poor prognosis of many cancers. The aim of this study was to evaluate the levels and clinical significance of BMI-1 in saliva of patients with salivary adenoid cystic carcinoma (SACC), and to analyze biological function and mechanism of BMI-1 in the invasion and metastasis of SACC. Materials and methods: The levels of BMI-1 in saliva and tumor tissues of SACC patients were determined. The correlation of salivary BMI-1 levels with clinicopathological parameters and clinical outcomes in patients with SACC was analyzed. Additionally, the effects of BMI-1 on wound-healing, transwell invasion, and epithelial-mesenchymal transition (EMT)-related protein expression in vitro as well as on tumorigenicity and experimental lung metastasis in vivo were investigated through exogenous overexpression and silencing of BMI-1 in SACC cells. Results: BMI-1 levels increased in saliva and tumor tissues in SACC patients with invasion or metastasis. High salivary BMI-1 levels were correlated with poor TNM stage, poor overall survival, and disease-free survival. Exogenous expression of BMI-1 in SACC-83 promoted its migration and invasion, while silencing BMI-1 in SACC-LM inhibited its migration and invasion in vitro and suppressed tumorigenesis and lung metastasis in vivo. Furthermore, BMI-1 regulated the expression of EMT-related proteins in SACC. Conclusion: Our study shows that BMI-1 can serve as a valuable biomarker to identify tumor invasion and metastasis in SACC, predict its prognosis, and act as a promising therapeutic target for SACC.

Study on the application of quality control circle activity in postoperative nursing of elderly dental implants.

BACKGROUND: To explore the application effect of "quality control circle" activity in postoperative nursing of elderly dental implants. METHODS: From January 2022 to December 2022, a total of 60 elderly patients were selected and divided into an experimental group and a control group, with 30 cases in each group using the random number table method. The elderly patients with dental implants received postoperative care under the supervision of a quality control circle. The control group was treated with conventional nursing methods. The success rate, postoperative complications, and satisfaction of the 2 groups were compared. RESULTS: By comparing the postoperative care effect of the 2 groups of patients, the satisfaction of the experimental group and the control group was 93.3% and 73.3%, respectively, showing the satisfaction of the experimental group was higher than the control group (P < .05). The planting success rate of the experimental and control groups were 96.7% and 66.7%, respectively, with the experimental group outperforming the control group (P < .05). The proportion of complications in the experimental was found to be fewer (6.7%) than in the control group (33.3%) (P < .05). CONCLUSION: Quality control circle activities can effectively improve the success rate of dental implants, reduce the occurrence of postoperative complications, improve patient satisfaction, and help medical staff in providing better treatment for patients.

Accuracy of Microimplant Placement Using a 3D Guide Plate for Orthodontic Anchorage.

This study aimed to design a three-dimensional (3D) guide plate using computer-aided design and a 3D printing system for precise implantation of microimplants for orthodontic treatment and investigate the accuracy and feasibility of a 3D guide plate in clinical practice. A total of 30 microimplants were placed in 15 patients in the Department of Stomatology, Affiliated Hospital of Jiangnan University. Before surgery, DICOM data from cone-beam computed tomography (CBCT) scans and STereoLithography data from the 3D model scan were imported to 3Shape Dental System. Data fitting and matching were performed, and 3D guide plates were designed primarily focusing on the thickness of guide plates, amount of concave compensation, and dimensions of the ring. Assist implantation method was used to place the microimplants, and postoperative CBCT images were used to evaluate the position and implantation angle. The feasibility of placing microimplants and precise implantation guided by the 3D guide plate. CBCT data before and after the placement of microimplants were compared. Regarding the secure positioning of microimplants based on CBCT data, 26 implants were categorized as Grade i, four as Grade ii, and none as Grade iii. No loosening of microimplants 1 and 3 months after surgery was reported. The implantation of microimplants is more accurate under the guidance of a 3D guide plate. This technology can achieve accurate implant positioning, thus ensuring safety, stability, and improved success rates after implantation.

Fractional derivative modeling for characterizing stress relaxation properties of Hami melon during drying.

The viscoelastic properties of food materials will change significantly while drying is in progress, which greatly influences the food deformation caused by drying. This study aims to predict the viscoelastic mechanical behavior of Hami melon during drying using the fractional derivative model. To characterize the relaxation characteristics, based on the finite difference method, an improved Grünwald-Letnikov fractional stress relaxation model is proposed to derive an approximate discrete numerical solution of the relaxation modulus by applying the time fractional calculus. The Laplace transform method is used to verify the obtained results, and the equivalence of the two methods is proved. In addition, the stress relaxation tests prove that the fractional derivative model has a better prediction effect on the stress relaxation behavior of viscoelastic food than classical Zener model. The significant correlations between the fractional order and the stiffness coefficient and the moisture content is also studied. Which is negative correlation and positive correlation respectively.

The clinical effect of ossotide for injection in the treatment of condylar fracture.

OBJECTIVES: Patients with condylar fractures were treated with osteopeptide injections as an adjuvant therapy to assess pain control and changes in interleukin-1ß (IL-1ß) and bone G-gla protein (BGP) levels. MATERIALS AND METHODS: Eighty-two patients with a condylar neck fracture were randomly assigned to two groups. The control group received conventional surgical treatment, while the experimental group received osteopeptide injections in addition to surgery. Pain level, IL-1ß, and BGP levels were evaluated at 1, 2, and 4 weeks postsurgery. RESULTS: One and two weeks postsurgery, the experimental group had lower Numeric Rating Scale scores compared to the control group. In addition, the IL-1ß level in patients receiving osteopeptide injections was lower than the control group at all three evaluation points (1, 2, and 4 weeks postsurgery) and the BGP level was higher with statistically significant differences (P < 0.05). CONCLUSIONS: The administration of osteopeptide injections as an adjuvant therapy for patients with condylar fractures can effectively reduce pain and facilitate faster initiation of muscle function training. In addition, the reduction of inflammatory factors and promotion of active osteogenesis leads to quicker wound healing.

Precise extraction of impacted supernumerary tooth in the maxillary anterior region with a digital guide plate: A case report.

RATIONALE: Removal of impacted supernumerary teeth requires precision and accuracy to prevent iatrogenic injury to important anatomical structures during dental surgery and to improve postoperative healing. PATIENT CONCERNS: A 12-year-old girl visited our department for the assessment and management of her deviated front teeth. DIAGNOSIS: Impacted supernumerary tooth extraction in the maxillary anterior region. INTERVENTIONS: The digital guide plate was fabricated after the integration of cone beam computed tomography data with that obtained from scanning the patient's dental model. Impacted supernumerary tooth extraction was performed. OUTCOMES: The use of the digital guide plate and planting instruments made the removal of the impacted supernumerary tooth less invasive, faster, and more accurate, whereas the wound was smaller, and the patient experience more comfortable. LESSONS: Combining the digital guide plate with planting instruments offers a useful aid for the removal of impacted supernumerary teeth among the maxillary anterior region and is, thus, worth promoting.

Improved osteogenesis and angiogenesis of a novel copper ions doped calcium phosphate cement.

Improving the angio1genesis potential of bone-repairing materials is vital for the repair of cancerous bone defects. It can further facilitate the delivery of active substances with osteogenesis and anti-tumor functions, ultimately promoting the formation of new bone tissues. Copper ions (Cu2+) have been proved to be beneficial to angiogenesis. This study developed a new type of Cu-containing calcium phosphate cement (Cu-CPC) by incorporating with copper phosphate (CuP) nanoparticles with a photothermal anti-tumor effect. The results revealed that the main phases of all hydrated CPCs were hydroxyapatite, unreacted tricalcium phosphate and calcium carbonate. But the hydration products of CPC became thinner after the incorporation of Cu2+. With the increase of CuP concentration, the setting time of CPC was prolonged while the injectability and the compressive strength were increased. The release concentration of Cu2+in vitro was among 0.01 to 0.74 mg/mL, which showed a positive relation with CuP content. Mouse bone marrow stromal cells (mBMSCs) displayed higher adhesion activity, proliferation performance and expression of osteogenic genes and proteins on CPC with 0.01 wt% CuP (0.01Cu-CPC) and 0.05 wt% CuP (0.05Cu-CPC). When human umbilical vein endothelial cells were co-cultured with 0.01Cu-CPC and 0.05Cu-CPC extracts, the proliferation and angiogenesis-related gene and protein expression were significantly increased, and the in vitro tube formation capacity was promoted. However, higher CuP content inhibited the proliferation of mBMSCs. In conclusion, CPC with 0.01 wt% and 0.05 wt% CuP nanoparticles has the potential to promote bone formation around cancerous bone defects, which would be promising for bone regeneration and treatment of bone tumors.

Simvastatin increases cell viability and suppresses the expression of cytokines and vascular endothelial growth factor in inflamed human dental pulp stem cells in vitro.

BACKGROUND: In recent years, simvastatin has been demonstrated to be capable of inducing odontogenic differentiation in human dental pulp stem cells (DPSCs), which makes it a promising source for endodontic treatment in pulpitis. However, a comprehensive understanding of how simvastatin affects the behavior of DPSCs and its potential in pulpitis is still lacking. OBJECTIVES: In this study, we investigated the effects of simvastatin on the viability of inflamed DPSCs. The expression of cytokines and vascular endothelial growth factor (VEGF) was also studied in response to simvastatin treatment. MATERIAL AND METHODS: We characterized the cell viability, inflammatory reactions and the production of VEGF in inflamed DPSCs, induced by lipopolysaccharides (LPS). The methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, cell cycle, apoptosis analysis, quantitative reverse transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot analyses were performed. RESULTS: We observed that a low dosage of simvastatin accelerated cell proliferation , whereas its high dosage (>15 µg/mL) suppressed propagation. A simvastatin dose of 8 µg/mL was sufficient to promote cell growth and cell cycle progression in DPSCs treated with LPS. Meanwhile, simvastatin induced apoptosis. The expression of multiple cytokines, including interleukins (IL)-1, IL-4 and IL-1ß, and especially interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α), was significantly suppressed. Moreover, the protein secretion and mRNA transcription of VEGF was observed to be markedly inhibited by simvastatin by inactivating mitogen-activated protein kinase (MAPK) signaling. CONCLUSIONS: Taken together, these results suggested that simvastatin might be a potent ingredient to enhance cell proliferation, alleviate inflammation response and attune vasculogenesis in pulpitis.

Conservative orthodontic fixed appliance management of pediatric mandibular bilateral condylar fracture.

INTRODUCTION: Management of mandibular condylar fractures is difficult in children with their inherently dynamic and unstable deciduous and mixed dentitions. We present a variation of the conservative fixed orthodontic approach that was used as an adjunct to aid in the reduction of a bilateral condylar fracture in a pediatric patient. METHODS: A boy, aged 10 years 9 months, came with clinical signs and symptoms of mandibular fracture after being involved in a motor vehicle accident. A computed tomography scan showed a vertical fracture on the left condylar head, a displaced fracture of the right condylar neck, and a mandibular symphysis fracture. The patient was treated with an orthodontic fixed appliance instead of an arch bar splint, followed by elastic traction to achieve a proper occlusion and condylar remodeling. Follow-up appointments were made 2 weeks and 1, 2, 20, 37, and 49 months after treatment. RESULTS: Clinical recovery was observed 2 months after treatment. At the follow-up appointments at 20, 37, and 49 months, jaw function and occlusal relationship remained stable, and no ankylosis was observed. The computed tomography scans showed that the right condyle had remodeled, and the left condyle exhibited a slight curve in the head at 49 months posttreatment. The patient's satisfaction with these treatment results was high. CONCLUSIONS: Conservative treatment of a mandibular fracture by fixed orthodontic means is a viable treatment option that is relatively straightforward and cost-effective and has a high level of patient acceptance and comfort.