Objective To investigate the effects of different concentrations of 10-MDP calcium salts on biological behaviors of L929 fibroblasts in the periodontium. Methods The X-Ray diffraction (XRD) was used to examine 10-MDP calcium salts obtained by the three synthesized formulas. The cell proliferation and cytotoxicity of L929 was measured by CCK-8 method; the flow cytometry was used to detect cell apoptosis, and the protein expression of matrix metalloproteinase (MMP)-2 and MMP-9 was measured by Western blot. Results The XRD results confirmed that the 10-MDP calcium salts obtained by the three synthesized formulas were in different structures. In the CCK-8 assay, only the 1.0 mg/mL MDP-1 group caused a decrease in cell proliferation activity after 72 h. No cell apoptosis was induced in each group after 72 hours of culture. The secretion of MMP2 and MMP9 proteins in L929 cells were inhibited in 0.2 mg/mL and 0.1 mg/mL MDP-2 and MDP-1 groups. Conclusion 10-MDP calcium salts may not have a cytotoxic effect on the periodontium; they can exert an inhibitory effect on the destruction of the periodontium by inhibiting the secretion of MMP2 and MMP9.

Objective To investigate the risk and severity of degenerative joint diseases(DJD)in patients with temporomandibular disorder diseases(TMD) under different joint disc states. Methods A total of 156 temporomandibular joints in 78 TMD patients were divided into three groups based on MRI images: normal disc position, anterior disc displacement with reduction(ADDR) and anterior disc displacement without reduction(ADDNR). CBCT or CT images were used to diagnose DJD and assess the severity of condylar bone changes. The OR value of DJD under different joint disc states was estimated by Logistic regression, and the regression coefficient of the severity of condylar bone changes under different joint disc states was estimated by ordinary least square regression. Results Compared with the normal disc position, the OR value of DJD in ADDR group and ADDNR group were 4.652(P<0.001), 16.739(P<0.001), respectively. The regression coefficient for condylar erosion in the ADDR group was 0.646(P<0.001). The regression coefficients for condylar cysts, condylar erosion, condylar osteophytes, condylar flattening, condylar bone sclerosis of ADDNR group were 0.241(P<0.05), 1.486(P<0.001), 0.759(P<0.001), 0.566(P<0.001), 0.381(P<0.05). Conclusion ADDR and ADDNR are associated with the occurrence of DJD in TMD patients, and the risk of DJD is higher in ADDNR than in ADDR. The degree of condylar bone changes in ADDNR is more serious than that of ADDR.

Objective To investigate the mesiodistal space in the area of multi-consecutive mandibular incisors,using CBCT image data, in order to provide a theoretical basis for the restoration of missing mandibular incisors and dental implant surgery. Methods CBCT imaging data of 500 patients were selected. The mesiodistal space in the area of multi-consecutive mandibular incisors were measured and statistically analyzed, and the feasibility of different implant placement strategies was evaluated. Results The mesiodistal space between two mandibular central incisors was (10.72±1.10)mm, and the mesiodistal space between mandibular central and lateral incisors were (11.33±1.00)mm and (11.45±0.98)mm on the left and right sides, respectively. The mesiodistal space between three consecutive mandibular incisors were (15.69±1.25)mm and (15.79±1.26)mm on the left and right sides, respectively. The mesiodistal space between four consecutive mandibular incisors was (20.76±1.48)mm. There was a gender difference in the mesiodistal space between mandibular incisor positions, with males having slightly larger space than females. Conclusion The mesiodistal space between mandibular incisors is narrow. When two consecutive incisors are missing, only a few patients are available for two narrow diameter implants, while others have to choose cantilever restoration. When more than two mandibular incisors are missing, most patients are available for two narrow diameter implants, restoring with implant-supported fix partial bridges.

Objective Through three-dimensional morphological analysis of the distribution of three-dimensional fracture lines of mandibular condylar fractures, the distribution and alignment characteristics of condylar fractures were revealed, in order to provide re-ference for diagnosis and treatment and surgical plans in maxillofacial surgery. Methods The imaging data of 37 cases of mandibular condylar fractures undergoing spiral CT examination were selected for retrospective analysis. The spiral CT image data of the patients were imported into Mimics and 3-matic software to isolate, model and simulate the repositioning of the mandibular fracture block, and the fracture lines were copied on a healthy standard mandibular model to obtain the distribution map of the condylar fracture lines. Results The coronal condylar fracture had an oblique alignment, with no obvious fracture line in the superior interior and no obvious difference between the right and left lateral condylar fracture lines;the horizontal condylar fracture line had an external high and internal low alignment around the condylar neck, with a markedly reduced fracture line in the superior interior. Conclusion By analyzing the condylar fractures and using 3D Mapping technology, it was concluded that condylar fractures were mainly concentrated in the lateral aspect of the condyle accompanied by fracture fragments and detachment from the condylar process, which often required surgical threaded nail fixation. 3D Mapping technology could be used to provide preoperative virtual guidance on the angle, direction, and length of threaded nails, which could provide a direction to improve surgery accuracy.

Objective To investigate the incidence and risk factors of postoperative delirium(POD)after free flap reconstruction in patients with oral cavity cancer(OCC) and explore the correlation between prognostic nutritional index(PNI) and system immune inflammation index(SII) with POD in oral cavity cancer patients. Methods A retrospective analysis of 138 patients who underwent the free flap surgery for OCC in Xuzhou Central Hospital between January 2016 to March 2023 were performed. Eighty-nine were male and 49 were female. The average age was (60.04±10.89) years(range: 27 to 88). POD-related risk factors were analyzed with SPSS 26.0 software package. The association between risk factors and POD was analyzed by binary Logistic regression analysis. The effect of PNI and SII was evaluated using the area under the receiver operating characteristic curve(AUC-ROC), sensitivity and specificity. Results A total of 15(10.9%)patients had POD. Single factor analysis results indicated that delirium was associated with age≥60,PNI,SII,total protein, time of operation,tracheostomy, blood transfusion, sleep disturbance, ICU observation time, visual analogue scale(VAS)pain score and complications. Multiple Logistic regression analysis showed that the independent risk factors of delirium included age≥60, PNI, SII, blood transfusion, sleep disturbance and pain. The risk of POD was increased when PNI<50.075 and SII>754.308. AUC of the PNI&SII-prediction model was 0.919; Youden index was 0.689; sensitivity was 0.933 and specificity was 0.756. Conclusion PNI and SII are independent risk factors for POD and can be used as indicators to predict POD. The PNI&SII-prediction model has a good value for POD in patients with flaps for OCC, and can be used to clinically guide early intervention and treatment.

Objective To explore the expression level of PTK7 in OSCC, and study its potential biological function and clinical significance. Methods qPCR and Western blot were performed to detect the expression of PTK7 in OSCC cell lines and OSCC tissue specimens. siRNA interference technology was used to down-regulate the expression of PTK7 in HN6 and Cal27 cell lines. The effects of down-regulated PTK7 on the proliferation, migration, invasion of OSCC cells were detected by CCK-8 assay, plate cloning assay, cell scratch assay, Transwell assay. Immunohistochemistry was used to detect the expression level of PTK7 protein in 75 cases of OSCC tissue. Results The results of qPCR and Western blot showed that PTK7 gene and its coding protein were highly expressed in OSCC lines HN6 and Cal27, and the expression of PTK7 gene and its coding protein was higher in 6 fresh OSCC samples than in their paired adjacent normal tissues. Down-regulating the expression of PTK7 could inhibit the proliferation, migration and invasion of OSCC cells. In the 75 OSCC specimens, the expression level of PTK7 was significantly associated with the patients’ age, smoking and differentiation degree (P<0.05). Kaplan Meier survival analysis found that OSCC patients with high expression of PTK7 had poorer prognosis. Conclusion PTK7 is a potential oncogene in the occurrence and development of OSCC, and its expression level affects the biological function of OSCC cells. The characteristics of OSCC can be understood clinically according to the expression level of PTK7, and PTK7 can be used as an independent prognostic indicator for OSCC.

Objective To establish a risk prediction nomogram model associated with perioperative lower extremity deep venous thrombosis (LDVT) in patients with malignant tumor in head and neck. Methods A total of 224 patients diagnosed with malignant tumor in head and neck in Department of Oral and Maxillofacial Surgery of Xuzhou Central Hospital from January 2017 to December 2022 were selected as the research subjects. Based on the occurrence of LDVT, the patients were divided into the developing group (24 cases) and the non-developing group (200 cases). Clinical data of the two groups were collected, and univariate analysis and multivariate Logistic regression analysis were performed to investigate the independent risk factors of perioperative LDVT in patients with malignant tumor in head and neck. At the same time, a risk prediction nomogram model was established and receiver operator characteristic curve (ROC) was drawn to evaluate the prediction efficiency of the nomogram model. Results There were significant differences in hypertension, preoperative anticoagulation, D-dimer level, postoperative bed time and platelet/lymphocyte ratio (PLR) between the two groups (P<0.05). The risk prediction model was constructed based on the independent predictors obtained by multivariate Logistic regression analysis, and the area under the curve (AUC) of the model calculated by the R language software was 0.814 (95% CI:0.778-0.849), with good discrimination and calibration effect. Decision curve analysis confirmed that the net benefit of the prediction model was higher in the threshold probability interval of 10%-75%. Conclusion Establishing a risk prediction model based on hypertension history, preoperative preventive anticoagulation, D-dimer level ≥0.5 mg/L, postoperative bed time ≥3 d and PLR ≥176 can accurately predict the occurrence of perioperative LDVT in patients with malignant tumor in head and neck, which will help to provide individual risk assessment, guide treatment decisions and reduce the occurrence of LDVT complications.

Objective To compare the apical sealing of two kinds of warm gutta-percha filling techniques under two root canal preparation concepts. Methods One hundred and eight extracted permanent premolars were collected and stochastically divided into six groups, two control groups (n=12) and four experimental groups (A, B, C and D groups, n=21). Groups A and C were prepared to 50#02 as the master apical file; groups B and D were prepared to 25#08 as the master apical file. Then groups A and B were obturated with the traditional warm gutta-percha filling technique; groups C and D were obturated with modified warm gutta-percha filling technique. Six samples were randomly selected from each experimental group to prepare sections at 1, 3, and 5 mm, and the interfacial gap between the filling material and the dentin wall was observed. The apical microleakage of the rest of the teeth was observed with dye penetration and transparent teeth technique under a stereomicroscope. Results The microleakage value of the modified type was smaller than that of the traditional warm gutta-percha filling,and the difference was statistically significant (P<0.05). The microleakage value of preparation with 25#08 as the master apical file was smaller than that of preparation with 50#02, and the difference was statistically significant (P<0.05). The average value of dye leakage was group B < group C < group D < group A, and the differences were statistically significant between group A and each group, group B and group D (P<0.05), while the differences among remaining groups were not statistically significant. In the statistics of single and double root canals, the average value of dye leakage was still group B < group C < group D < group A, and the difference was statistically significant between group A and each experimental group, while the difference was not statistically significant between group B and group D. There was no statistically significant difference in the interfacial gap between groups and within groups, but a relatively small gap was found at 3 mm, and a large gap was found in groups C and D. Conclusion The traditional warm gutta-percha filling with 25#08 as the master apical file is better, which is as good as the modified warm gutta-percha filling with 50#02 as the master apical file. In the interface observation, it is easy to produce a large gap when using the modified warm gutta-percha filling.

Objective To handle severe horizontal defect of maxillary molar area deviating from dental arch curve with insufficient bone height, this case tried to use titanium mesh as a scaffold and combine maxillary sinus floor elevation to realize horizontal and vertical bone increment in local area. Methods Preoperative CBCT showed that the residual bone in 26 teeth was about 3.3 mm in width and 4.9 mm in height, and that in 27 teeth was about 5.2 mm in width and 5.1 mm in height. The patient was treated with titanium mesh to maintain buccal horizontal osteogenic space, and autogenous bone mixed with artificial bone was collected for bone grafting. At the same time, platelet-rich fibrin was applied, and the vertical bone mass was improved by lateral maxillary sinus floor elevation. Results Five months after operation, the titanium mesh was removed. CBCT showed that the bone width and height of 26 teeth were respectively increased by 2.0 mm and 3.2 mm compared with those before operation. The bone width and height of 27 teeth increased by 1.2 mm and 4.0 mm, and the ideal bone increment effect was obtained. Six months after operation, transalveolar maxillary sinus floor elevation and implant implantation were performed and the initial stability of the implant was good. One year after operation, the implant restoration was completed. CBCT showed that the bone width and height of 26 teeth were respectively increased by 2.9 mm and 4.5 mm compared with that before operation. The bone width and height of 27 teeth were respectively increased by 0.9 mm and 6.6 mm. The results showed that the bone increment effect was stable; the normal occlusal function was restored, and the aesthetic effect was improved to some extent. Conclusion Results of this case show that titanium mesh bone grafting combined with maxillary sinus floor elevation can obtain a relatively sufficient and stable bone increment effect, and it is a reliable method to improve the bone deficiency in maxillary molar area.

Periodontitis is a prevalent and persisting oral inflammation, during which host factors are critically involved. As the most abundant immune cells, neutrophils actively partake in periodontal homeostasis, the alteration of neutrophil number or function could aggravate periodontitis through multifaceted mechanisms. Additionally, neutrophil-targeted therapies showed promising effects on treating periodontitis in animal trials. In this paper, research progress of neutrophil’s role in periodontitis and immunomodulation on neutrophil were reviewed in order to provide new perspectives for periodontitis treatment.

The attachment is a crucial component in clear aligner treatment. The proper use of it is beneficial to tooth movement efficiency and thus to better achieve the goals of orthodontic treatment. This paper reviews research progress of the attachment including its types, considerations in design, and factors associated with the accuracy and loss rates, in order to provide reference for orthodontic clinicians.

Periodontally assisted accelerated osteogenic orthodontics(PAOO)is a clinical procedure that combines selective alveolar corticotomy and particulate bone grafting. Its biological theory is based on regional acceleration phenomenon(RAP). A large number of clinical studies have shown that PAOO can shorten the orthodontic time, increase the alveolar bone thickness and reduce the risk of root resorption. However, there is no systematic review to analyze the influence of PAOO on soft tissue. The objective of this review is to evaluate the effective evidence of PAOO in improving periodontal soft tissue, and to provide reference for clinical application of this technique.

Adenoid hypertrophy is a common condition in adolescents and children. Children with adenoid hypertrophy have a typical “adenoid face” with narrow maxilla, elongated mandible, high palatal lid, open lips, and lack of expression if the disease persists. The degree of adenoid hypertrophy is closely related to the effect of orthodontic treatment, and it is also one of the most common causes for obstructive sleep apneahypopnea syndrome(OSAHS) in children. Therefore, the diagnosis of adenoid hypertrophy is important to clinical practice. The orthodontist can use different parameters indexed in the images to analyze, make a diagnosis and finally assess the feasibility of orthodontic treatment and develop an orthodontic plan. This article mainly reviews and summarizes imaging measurements and diagnosis of adenoid hypertrophy for orthodontic clinical treatment.

Digital impression technology has become one of the more commonly used impressions in clinical practice and is widely used in the field of removable partial denture restorations for dental defects. This article introduces the application of digital impression technology in removable partial denture restorations and reviews the factors influencing the accuracy of digital intraoral impressions in order to provide guidance for clinical application.

Interproximal contact loss is a common complication following oral implant restoration, with a relatively high incidence rate and distinct anatomical and physiological characteristics. It is prone to cause food impaction, tissue trauma around implants and lead to caries or periodontal inflammation in surrounding teeth. The treatment options for interproximal contact loss are limited, impacting the prognosis of implant restoration and patients’ satisfaction. Therefore, research on interproximal contact loss in implant-supported fixed dental prostheses is of great importance.