The 5th edition of the Classification of Head and Neck Tumours by the World Health Organization (WHO) was published in March 2022. In the section on oral cavity and mobile tongue tumours, the classification of epithelial tumours in the 5th edition has undergone several modifications compared to the 4th edition published in 2017. Notably, oral potentially malignant disorders (OPMD) and oral epithelial dysplasia (OED) have been addressed separately, and in-depth discussions have been included regarding submucosal fibrosis (SF) and human papillomavirus (HPV)-associated oral epithelial dysplasia (HPVOED). Additionally, the section on squamous cell carcinoma (SCC) now includes carcinoma cuniculatum (CC) and verrucous carcinoma (VC), emphasizing their distinctive clinical and histological characteristics. This review provides a comprehensive overview of the most recent advancements in clinical, histological, and molecular research on epithelial tumours of oral cavity and mobile tongue since 2017.

The structural and functional heterogeneity of cells in bone tissue is closely related to their spatial location. Spatial transcriptomics can simultaneously obtain location information and transcriptome changes of spatial units within tissues. In recent years, the rapid development of spatial transcriptomics has enabled high-resolution and high-throughput transcriptome analysis of tissues and organs, and has been continuously applied in the study of the skeletal system. This article reviews the progress of spatial transcriptomics and its applications in bone research.

Objective: To establish a design program for orthognathic surgical splints based on artificial intelligence (AI), and to compare the precision between the AI splints and manual digital splints. Methods: This research established an AI algorithm for orthognathic surgical splints and obtained the available automatic design program. The time required for designing surgical splints in the same case was compared. Besides, 40 dentition models of patients with skeletal Class Ⅱ malocclusion (20 for mandibular surgery, and 20 for bimaxillary surgery) were included for comparison. The splints were designed by AI program and manual digital software respectively and scanned for the digital data to compare the difference. Results: The overall deviation between the AI and manual digital splints in guiding the positioning of the models was less than 0.1 mm, indicating that there was no significant difference between them. Comparison of cusp position showed that the mean deviation distance between the AI and manual digital splints was about 0.10-0.14 mm. The application of the AI program can greatly reduce the design time in both the mandibular surgery [(10.7±2.4) s] and the bimaxillary surgery [(21.5±3.9) s]. Conclusion: There is no significant difference in accuracy between AI and manual digital splints, and AI program can improve the design efficiency of orthognathic surgical splints.

Objective: To evaluate the clinical effect of carbon dioxide fractional laser in early treatment of postoperative scar of primary cleft lip. Methods: A total of 24 children who had undergone primary cleft lip repair in the treatment group were treated with carbon dioxide fractional laser within three months after operation, and 24 children who had undergone primary cleft lip repair in the control group were not treated with laser after operation. Based on the subjective assessment by comparing photographs before and after the treatment and the objective assessment using Vancouver scar scale (VSS) scoring method, the scar conditions of the two groups were compared one year after laser therapy. Results: The total effective rate of the treatment group was 91.7% after the completion of the whole course of 4 treatments after 1 year, and the difference between the two groups was statistically significant (P<0.05). The objective assessment results showed that the difference between the two groups was statistically significant (P<0.05). Conclusion: Carbon dioxide fractional laser is effective in the early treatment of postoperative scar of primary cleft lip, which is worthy of clinical application.

Temporomandibular joint osteoarthritis (TMJOA) is a common clinical disease. However, the pathogenesis of TMJOA is still unclear, and there is a lack of effective treatment, bringing great distress to patients. Therefore, it is of great significance to explore the pathogenesis of temporomandibular arthritis and to find effective therapy. Recent studies have shown that noncoding RNA (ncRNA) is involved in regulating the development of TMJOA and has great potential in the diagnosis and treatment of TMJOA. Thus, ncRNA is expected to become new diagnostic marker and therapeutic target. We will review the research progress of noncoding RNA in temporomandibular arthritis.

Objective: To explore the clinical effect of Piezocision guided by three dimensions (3D) printing guide plate to assist skeletal Class Ⅱ malocclusion correction. Methods: Twenty-four patients with skeletal Class Ⅱ malocclusion were selected from our hospital. The treatment plan involved the extraction of the bilateral maxillary first premolars and anterior retraction by mini-implant anchorage in upper arch. The patients were randomly divided into two groups: The control group underwent conventional orthodontic treatment, while the research group underwent Piezocision guided by 3D printing guides at the beginning of the space-closing phase of the orthodontic treatment. The loading method was the same as that of the control group after the operation. The indexes related to the changes of hard and soft tissues and the treatment effects of the two groups were recorded for analysis and comparison. Results: In the research group, the change value of U1-SN was (-1.49±2.18)°，U1-NA was (-5.63±3.39)°，NA-Apo was -4.10 (-4.60, -2.00)°，U1-Apo was (-3.10±0.95) mm. There was significant difference comparing with the control group. The average speed of movement of the teeth in the research group during the process of space closure was (0.90±0.21) mm per month, which was significantly faster than that of the control group [(0.54±0.15) mm per month]. None of the roots were damaged after operation, and there was no significant difference in the degree of root resorption and the depth of periodontal probing between the research group and the control group after the treatment. Conclusion: In skeletal ClassⅡmalocclusion correction, 3D printing-guided Piezocision can effectively realize the overall movement of the maxillary anterior teeth, shorten the treatment time, and have fewer surgical complications, which can be viewed as an effective adjuvant treatment of patients with skeletal ClassⅡmalocclusion undergoing orthodontic treatment.

Objective: To investigate the expression and clinical significance of E2F transcription factor 1 (E2F1) in oral squamous cell carcinoma (OSCC), and to analyze its function in apoptosis and cell cycle. Methods: The correlation between E2F1 expression and clinicopathology in OSCC was analyzed based on R language and The Cancer Genome Atlas (TCGA) database. The main biological processes involved in E2F1 were identified by gene set enrichment analysis (GSEA). Western blotting and real-time quantitative polymerase chain reaction (RT-qPCR) were used to detect E2F1 expression in OSCC patients' tissue. After increasing and knocking down the expression of E2F1 in SCC15 cell lines by cell transfection, the effect of changes in E2F1 expression on apoptosis and cycle of SCC15 cells was analyzed by flow cytometry. Results: E2F1 was highly expressed in the OSCC-related TCGA dataset and correlated with T-stage (T2 or T4 vs T1), histological grade (G2 or G3 vs G1), clinical stage (Ⅲ vs I), age (middle vs young), and gender (male vs female) (P<0.05), which were mainly enriched in the genome of cell cycle or nucleotide excision repair [P<0.05 and false discovery rate (FDR) <0.25]. Both mRNA and protein expression of E2F1 were upregulated in the tissues of 37 OSCC patients (P<0.001). The expression of upregulated E2F1 decreased the rate of apoptosis in SCC15 cells (P<0.05), and also decreased the rate of G1 phase (P<0.01) and increased the rate of S phase (P<0.001) in the cell cycle. Conclusion: E2F1 is highly expressed in OSCC and can inhibit apoptosis and promote G1/S phase transition in the cell cycle.

Objective: To investigate the effect of local injection of desferrioxamine (DFO) on the bone remodeling of alveolar bone through the regulation of osteoclasts by hypoxia inducible factor-1α (HIF-1α). Methods: DFO was injected locally into the alveolar bone of C57 mice; changes in alveolar bone volume were observed by micro-CT and histological staining; osteoclastogenesis was observed by immunofluorescence and tartrate-resistant acid phosphase (TRAP) staining; the effects of DFO on the differentiation of Raw264.7 to osteoclasts via HIF-1α were observed in vitro by TRAP staining and immunofluorescence. Results: Micro-CT and histological staining showed that local bone density decreased and bone volume decreased after local injection of DFO; histological staining revealed that the number of local osteoclasts increased and HIF-1α expression increased in the DFO injection group compared with the control group; in vitro cell culture revealed that DFO promoted the expression of HIF-1α in Raw264.7 cells and its differentiation to osteoclasts. Conclusion: Local injection of DFO can promote bone remodeling of alveolar bone and differentiation of Raw264.7 into osteoclasts.

Objective: To observe the effect of resveratrol on the chemoresistance of oral squamous cell carcinoma (OSCC) cells induced by cisplatin (DDP), and to explore the related mechanism. Methods: CAL-27/DDP cells in logarithmic phase were taken and randomly divided into control group (conventionally cultured), resveratrol group (added resveratrol 200 μmol/L), agonist group [added tumor necrosis factor-α (TNF-α) 10 ng/mL], resveratrol combined with agonist group (added resveratrol 200 μmol/L, TNF-α 10 ng/mL). All groups were cultured for 48 h for subsequent experiments. The inhibition rate of cell proliferation was detected by MTT method. Double staining was used to detect the apoptosis rate. Intracellular DDP accumulation and retention were examined. Western blotting was used to detect the protein expressions of P-glycoprotein (P-gp), topoisomorases Ⅱ (Topo Ⅱ), nuclear factor-κB (NF-κB) p65, phosphorylated NF-κB (p-NF-κB) p65, inhibition of NF-κBα (IκBα) and phosphorylated IκBα(p-IκBα). Results: Compared with the control group, the proliferation inhibition rate, apoptosis rate, drug accumulation, drug retention, and TopoⅡprotein expression were increased, and the expression of P-gp protein, as well as the ratios of p-NF-κB p65/NF-κB p65, p-IκBα/IκBα protein expression were decreased in the resveratrol group (P<0.05). Also compared with the control group, the proliferation inhibition rate, apoptosis rate, drug accumulation, drug retention, and Topo Ⅱ protein expression were decreased, P-gp protein expression, p-NF-κB p65/NF-κB p65, p-IκBα/IκBα protein expression ratios were increased in the agonist group (P<0.05). Compared with the resveratrol group, the proliferation inhibition rate, apoptosis rate, drug accumulation, drug retention, and TopoⅡprotein expression were decreased, while the expression of P-gp protein, and the ratios of p-NF-κB p65/NF-κB p65, p-IκBα/IκBα protein expression were increased in the resveratrol combined agonist group (P<0.05). Compared with the agonist group, the proliferation inhibition rate, apoptosis rate, drug accumulation, drug retention and TopoⅡprotein expression were increased, while the expression of P-gp protein and the ratios of p-NF-κB p65/NF-κB p65, p-IκBα/IκBα protein expression were decreased in the resveratrol combined with agonist group. Conclusion: Resveratrol can reduce the chemotherapy of cisplatin-induced OSCC cells, and its mechanism may be related to the inhibition of NF-κB pathway.

Objective: To compare the influence between retromandibular transmasseteric anterior parotid approach (RMTMAP) and retromandibular transparotid approach (RMTP) on the facial nerve damage and salivary fistula in the treatment of condylar fractures. Methods: A comprehensive literature search of randomized controlled trials on surgical approaches for condylar fractures was undertaken in various Chinese and English databases (the Cochrane Library, PubMed, Embase, CNKI, CBM, VIP, Wanfang and Chinese Clinical Trial Registry). The search period is from the establishment of the database until now (November 2021), and manual search is carried out to avoid omissions. A total of 7 studies restricted in randomized controlled trials were included, and the quality of these studies was moderate to high. RevMan 5.3 software was used to perform meta analysis. Results: A total of 7 studies were included in this study, and the results showed that patients in both groups could achieve satisfactory results after surgery. The incidence of postoperative facial nerve injury in RMTMAP group was lower than that in RMTP group [relative risk (RR)=0.49, 95%CI=0.25-0.97]. P=0.04], and the incidence of postoperative salivary fistula was lower in the RMTMAP group (RR=0.35, 95%CI=0.15-0.85, P=0.02). The difference between the two groups was statistically significant. Conclusion: A lower incidence of postoperative facial nerve injury and salivary fistula was observed in RMTMAP group than that in RMTP group. Therefore, RMTMAP deserves clinical application.

Objective: To explore the changes in condyle cartilage development and primary ciliary gene expression after changes in masticatory force.Methods: Three-week-old C57BL/6J male mice were divided into 3 groups, and they were fed with normal diet (ND) for 2 weeks, soft diet (SD) for 2 weeks, and fed with 1 week of soft diet than 1 week of re-normal diet (RND). After collecting the samples, safranin O-fast green staining, toluidine blue staining, Masson staining, alkaline phosphatase (ALP) staining, and collagen typeⅡ(COL2) immunofluorescence staining were performed to observe changes in the condylar cartilage and subchondral bone. Primary ciliary gene expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Results: Compared with the ND group, the SD group has thinner condyle cartilage, less extracellular matrix, and subchondral bone structure has changed. The primary cilia gene expression (Ift88, Ift140, Ptch1, Smo, Gli1) was decreased. Compared with the SD group, the above changes recovered in the RND group. Conclusion: Changes of masticatory force during growth will affect the development of condyle cartilage and primary ciliary gene expression in mice.

Objective: To evaluate the therapeutic effect, advantages, and disadvantages of digital polyetheretherketone cyst plug in fenestration decompression of jaw cyst. Methods: A total of thirteen patients with jaw cyst who underwent surgery in Tongji University Stomatological Hospital from 2021 to 2022 were treated with fenestration decompression and digital polyetheretherketone cyst plug after operation. Through clinical examination and imaging data, the effect of digital polyetheretherketone cyst plug was evaluated. Postoperative follow-up was conducted regularly to observe the shrinkage of cyst cavity, the formation of new bone, the occurrence of complications and the wearing satisfaction of cyst plug. Results: In some cases, mild mouth opening restriction and cheek swelling appeared in those who pulled out the impacted teeth in the capsule cavity at the same time of fenestration. Questionnaire survey showed that all indexes were acceptable or satisfactory except one patient who was dissatisfied with the appearance of cyst plug. The new bone deposition rates measured in 3, 6, 9, 12 months after operation were 71.03% (59.37%, 82.84%), 82.75% (77.25%, 88.66%), 89.93% (86.41%, 95.08%), and 94.21% (90.21%, 95.09%) respectively. The reduction rates of cysts measured in 3, 6, 9, 12 months after operation were 96.91% (92.47%, 98.65%), 100% (98.36%, 100%), 100% (99.79%, 100%), and 100% (100%, 100%) respectively. Conclusion: Digital polyetheretherketone cyst plug, with its unique material advantages and design advantages, has achieved good therapeutic effect in the application of fenestration decompression, and patients' wearing satisfaction is high, which is worthy of further promotion.

Objective: To study the effect of long non-coding RNA-EPS (lincRNA-EPS) on osteoclastogenesis of RAW264.7 cells induced by receptor activator for nuclear factor-κB ligand (RANKL) and lipopolysaccharide (LPS). Methods: RAW264.7 cell strain overexpressing lincRNA-EPS (lincRNA-EPS OE strand) and its negative control strain were generated by transfection of lincRNA-EPS overexpressing vector and negative control vector and subsequent screening. Osteogenesis was induced with either RANKL or LPS (after pretreatment with RANKL). The cells were then stained with tartrate resistant acid phosphatase staining (TRAP staining) kit to count the number and observe the morphology of osteoclasts. Phalloidin staining was performed to detect the F-actin rings and therefore to evaluate bone-resorbing ability of osteoclasts. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to measure the mRNA levels of osteoclast-associated genes. Results: RAW264.7 cell strain overexpressing lincRNA-EPS and its negative control strain were generated. Neither strain showed significant difference during osteoclastogenesis (P>0.05), either induced by RANKL or LPS; for osteoclastogenesis by LPS induction, TRAP staining showed that significantly more osteoclasts were generated from lincRNA-EPS OE strain (P<0.05), while phalloidin staining showed that larger F-actin rings were generated from lincRNA-EPS OE strain, and RT-qPCR also showed that the mRNA levels of 4 osteoclastogenesis-related genes (TRAP, CTSK, DC-STAMP and ATP6v0d2) after induction were significantly lower in lincRNA-EPS OE strain (P<0.05); however, those difference were not present (P>0.05) when osteoclastogenesis was induced by RANKL. Conclusion: The overexpression of lincRNA-EPS inhibits LPS-induced osteoclastogenesis and the function of osteoclasts. However, the overexpression of lincRNA-EPS does not affect RANKL-induced osteoclastogenesis significantly.

Decompression is a surgical method for the preservation treatment of large jaw cysts, and a cyst plug with excellent performance is a necessary condition to ensure the therapeutic effect of this method. Making drainage port through cyst plug, balancing the pressure inside and outside the cyst cavity, and washing with postoperative physiological saline can effectively reduce the volume of the cyst cavity, and reduce the risks of nerve injury, adjacent tooth and tooth germ injury and pathological fracture of jaw caused by traditional radical surgery. In this paper, the classification and application of common cyst plugs after fenestration decompression of large jaw cysts, and the application of cyst plugs combined with negative pressure suction in recent years are reviewed.

After implantation of implants as foreign bodies into the jawbone, the immune and skeletal systems of the body regulate and adapt to each other, promoting bone resorption and remodeling around the implants. The imbalance of foreign body response may lead to loss of bone around the implants. This article summarizes the relevant factors that may trigger peri-implant immune response and lead to bone resorption, including peri-implant microbial infection, implant overload, poor overall condition, and biological wear of implant materials. Osteoclasts are currently the only known cells in the human body that can cause bone resorption, so their generation has been used as a clue to sort out several key pathways and factors that regulate this process, such as macrophage polarization, receptor activator of nuclear factor-κB ligand (RANKL) / receptor activator of nuclear factor-κB (RANK) / osteoprotegerin (OPG) pathway and nuclear factor-κB (NF-κB) pathway. This review discusses the immune mechanism of peri-implant bone loss, providing insights for understanding the concept of osseointegration and treating peri-implant bone loss from an immune perspective.

Carcinosarcoma (CS) is a highly malignant tumor composed of malignant epithelial elements and malignant mesenchymal elements, with a very low incidence rate. This paper reports a case of parotid carcinosarcoma composed of salivary duct carcinoma and angiosarcoma, and discusses the incidence, immunohistochemical analysis, diagnosis and differential diagnosis, pathogenesis, tissue source, treatment and prognosis of parotid carcinosarcoma in combination with relevant literature in order to improve clinicians' further understanding of the disease and improve the further classification of parotid carcinosarcoma pathology.

With the continuous explorations and researches of osteocytes, osteocytes are no longer mistaken for a kind of quiescent and passive cells, but active and positive cells, which play important regulatory roles in osteoblasts and osteoclasts. While an increasing number of studies have identified key signaling pathways and crosstalk mechanisms related to osteocytes. To some extent, the role of osteocyte apoptosis and its complex mechanisms occurring in various states of pathologies are still not elucidated. If further studies can be performed, this will help to fully understand the function and mechanism of osteocytes in a variety of states, as well as provide a novel target for bone diseases. At present, there are many reports about osteocytes regulating osteoblasts and osteoclasts. In this paper, the research progresses in regulation and mechanism of osteoblasts and osteoclasts by osteocytes are reviewed.

The role of bone marrow mesenchymal stem cells (BMSCs) in bone defect repair and bone regeneration has been extensively studied. Much evidence suggests that effective endogenous bone regeneration requires coordination of the immune system. The interaction between immune cells and BMSCs is crucial to promoting bone formation in the healing of bone defects. In recent years, it has been found that a variety of immune cells promote osteogenic differentiation of BMSCs through the release of cytokines and signals. It is beneficial to bone defect repair and bone regeneration, and becomes a new therapeutic target for bone defect repair. Therefore, this article reviews the research status of the osteogenic effect of immune cells on BMSCs and related mechanisms.

Objective: To explore the application effect of light sedation technique in impacted tooth extraction in patients with anxiety. Methods: Intravenous infusion of propofol was administered to 20 patients with mandibular impacted teeth anxiety, and the impacted teeth were removed when the bispectral index (BIS) reached 80-85. The patients' heart rate (HR), mean arterial pressure (MAP), respiratory rate and blood oxygen saturation were monitored during operation, and the patients were instructed to record the visual analogue scale (VAS) after operation, and were asked about anterograde amnesia. SPSS 20.0 software package was used for data statistics, paired t test was used to compare the differences between intraoperative physiological indexes and the time of admission, and descriptive analysis was used to analyze the intraoperative pain of the patients. Results: All patients successfully completed the operation, and there were no obvious adverse reactions during the operation.There were no abnormalities in HR, MAP, respiratory rate and blood oxygen saturation. The postoperative VAS scores of the patients were 1-3, and the patients' anterograde amnesia of the start of surgery, mucosal incision and dental drill sound were recorded, which means that the anxiety was relieved. Conclusion: For the removal of mandibular impacted teeth in patients with dental anxiety, propofol intravenous light sedation technology (BIS=80-85) can achieve satisfactory results, reduce patients' anxiety and improve comfort.

Objective: To explore the effect of zinc finger protein 260 (Zfp260/ZNF260) on macrophage polarization and alveolar bone resorption due to periodontitis. Methods: Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of ZNF260/Zfp260 in inflammatory periodontal tissues of human/wild-type mice. The expression of Zfp260 in RAW264.7 cells in inflammatory or non-inflammatory environments was detected by RT-qPCR. Mice with specific knockout of Zfp260 were bred, and control mice (Zfp260^f/f; Lyz2-cre^-) and conditional knockout (cKO) mice (Zfp260^f/f; Lyz2-cre⁺) periodontitis models were established respectively. Morphological changes of alveolar bone were detected by micro-CT and hematoxylin-eosin (HE) staining. The polarization of RAW264.7 cells when Zfp260 was knocked down via specific small interfering RNA (siRNA) in an inflammatory environment was detected by RT-qPCR and western blotting. RT-qPCR and immunofluorescence staining were used to observe the expression of M1 and M2 macrophage-associated markers in periodontal tissues. Results: The expression of ZNF260/Zfp260 in inflammatory periodontal tissues of human/wild-type mice were significantly higher than that of healthy periodontal tissues. The expression of Zfp260 in RAW264.7 cells was significantly increased in an inflammatory environment. Alveolar bone resorption in the ligatured side of cKO mice was significantly less than that of flox/flox mice. The knockdown of Zfp260 in RAW264.7 cells could inhibit its M1 polarization in an inflammatory environment. The expression of M1-related markers in inflammatory periodontal tissues was significantly lower than that of flox/flox mice. Conclusion: Inhibition of Zfp260 in macrophage decreased M1 polarization and rescued the bone loss due to periodontitis.

The application of deep learning (DL) has become widespread with the development of digital medicine. At present, DL has been gradually applied to the fields of stomatology. Multiple studies have applied DL, combined with preoperative examination images such as X ray and cone beam CT (CBCT) images, to assist clinical diagnosis and decision-making in dealing with impacted mandibular third molar (IMTM). Besides, inferior alveolar nerve (IAN) injury is one of the most serious sequelae after extraction of IMTM. Combined with imageological examination, DL can provide objective and accurate estimation of the risk of IAN injury to improve the outcome of treatment. This paper reviews the current application of DL in preoperative image recognition, preoperative auxiliary diagnosis and evaluation, and IAN injury prognosis prediction in the extraction of IMTM, and looked into the role of DL in the extraction of IMTM in the future.

Objective: To investigate the clinicopathological features and prognosis of recurrent pleomorphic adenoma (RPA) of minor salivary glands. Methods: The clinical data of patients with RPA of minor salivary glands in our hospital from January 2011 to December 2020 were retrospectively collected. In combination with literature review, the clinicopathological characteristics and prognosis were analyzed. Results: A total of 17 cases of RPA of minor salivary glands were collected, including 5 males and 12 females. The age ranged from 14 to 80 years, with a median age of 52 years. The average recurrence frequency was 2.8 times, and the average recurrence interval was 7.9 years. It was most common in the palate (52.9%), followed by the buccal (29.4%). Large recurrent tumors may cause certain symptoms, such as bone absorption, pharyngeal cavity obstruction and facial swelling. A total of 7 (41.2%) of 17 patients underwent malignant transformation, and 5 (55.6%) of 9 cases in the palate underwent malignant transformation. The prognosis of surgical treatment was good, with an average follow-up of 5.7 years, and 15 patients (88.2%) were tumor-free status. Conclusion: RPA of minor salivary glands is a rare critical tumor, which often occurs in the palate and has a long recurrence interval. RPA of small salivary gland is prone to undergo malignant transformation, and the prognosis of surgical treatment is good.

The complete resection of tumor and metastatic cervical lymph nodes are the key to the successful surgical treatment of oral cancer. However, during the operation, surgeons do not have a convenient and effective auxiliary means to evaluate the completeness of tumor eradication, in addition to relying on frozen biopsy techniques. In recent years, with the development of near-infrared fluorescence (NIF) imaging, fluorescence-guided surgery (FGS) has gradually evolved, providing important real-time intraoperative assistance for surgeons, and has also been widely recognized and applied in clinical practice. The application of fluorescence imaging in the surgical treatment of oral squamous cell carcinoma (OSCC) is still in its early stages. This article introduces the specific clinical application scenarios of this technology in oral cancer surgery, discusses the current challenges, and looks forward to future development, so as to provide reference for its clinical application and research.

α-ketoglutarate (AKG) is an essential intermediary metabolite of the tricarboxylic acid (TCA) cycle and amino acid metabolism. By participating in the generation of adenosine-triphosphate (ATP) and the biosynthesis of a variety of important amino acids and proteins, it is widely involved in a series of important physiological processes. Since there are few reports on the research of AKG in stomatology, this paper reviews the physiological function of AKG and its research advances in stomatology, which may lay a theoretical foundation for broadening the application of AKG in stomatology.

Objective: To measure the labial bone thickness of mandibular anterior teeth and depth of medial lingual foramina (MLF) by cone beam CT (CBCT) and to provide data for immediate implant in the mandible anterior region. Methods: Two hundred patients aged 18 to 40 years old were selected. CBCT was used to measure the labial bone thickness at 2.0 mm (P1), 5.0 mm (P2) and 8.0 mm (P3) below the enamel-cemental junction of mandibular central incisors, mandibular lateral incisors and mandibular canines, and the distance between the MLF and the alveolar crest. The means and standard deviations were calculated, and the data was statistically analyzed by SPSS 25.0. Results: At P1, the percentage of the thickness of mandibular central incisors, lateral incisors and canines less than 1.0 mm was 81.0%, 87.0% and 91.5%; at P2, the percentage of the thickness of mandibular central incisors, lateral incisors and canines less than 1.0 mm was 94.0%, 98.0% and 95.0%; at P3, the percentage of the thickness of mandibular central incisors, lateral incisors and canines less than 1.0 mm was 35.5%, 65.5% and 70.0% respectively. The labial bone thickness in male patients of mandibular central incisors at P2 and canines at P2 and P3 were thicker than that in female patients (P<0.05). The detection rate of MLF was 97.9% for male patients and 96.2% for female patients, with no significant difference (P>0.05). The closest distance between the MLF and alveolar crest was 11.4 mm. 7.2% of the distance were less than 14.0 mm, 78.4% of the distance were concentrated between14.0 mm and 24.0 mm, and 14.4% of the distance were more than 24.0 mm. The majority of MLF was 1, accounting for 72.2%, and the maximum number was 3. "Large lingual foramina" with excessive diameter was also found. Conclusion: Most of the labial bone thickness in mandible was less than 1.0 mm, and only got thickened at 8.0 mm below the enamel-cemental junction of mandibular central incisor. The MLF is generally safe for implant, but there are variations in location, number, and diameter.

Plunging ranulas are relatively rare cystic mass in the neck, which are mucous extravasation or retention pseudocysts from the sublingual gland, without the epithelial linings. They plunge inferiorly into the neck by extending beyond the free edge of the mylohyoid muscles or through the dehiscences of the muscles. We report a case of plunging ranula treated in our hospital, with recurrence seven months after the intraoral sublingual gland excision. The literatures associated with pathogenesis, clinical presentation, differential diagnosis, surgical approach and recurrent causes are reviewed.

Objective: To introduce the surgical technique of temporomandibular joint disc anchoring through a modified tragus incision.Methods: From February 2017 to October 2021, 264 patients (328 sides of joints) with advanced anterior disc displacement without reduction (ADDWoR) admitted to our hospital were treated with temporomandibular joint disc anchorage using a modified tragus approach. The specific method was as follows: Use a modified intraauricular approach to separate the superficial temporal fascia and the deep and superficial layers of the deep temporal fascia, as well as the joint capsule, cut the joint capsule at the root of the zygomatic arch, expose the joint disc, using a Mini Mitek anchor screw to fix it at the posterior and lower pole of the condylar process, and using two Orthocor sutures for horizontal mattress suture to reposition the anterior displaced joint disc. Magnetic resonance imaging (MRI) of the temporomandibular joint was performed before and within 7 days after surgery. The facial nerve condition was observed from 1 to 7 days after surgery, follow-up MRI was performed 3 months after surgery, and the mouth opening degree was recorded at 1 week, 1 month, and 3 months after surgery. The visual analog scale (VAS) was used to record the relief of temporomandibular joint pain in patients at 3 months after surgery. The vancouver scar scale was used to evaluate the scar condition in the surgical area at 3 months after surgery. Results: According to the evaluation of postoperative MRI, 306 joints (249 cases) were evaluated as "excellent", 20 joints (14 cases) were evaluated as "good", and 2 joints (one case) were evaluated as "poor". The successful reduction rate was 99.39% (326/328 sides). Only one patient evaluated as "poor" after surgery, accounting for 0.61% (2/328 sides). At the 3-month follow-up after surgery, all patients showed improvement in limited mouth opening, with pain scores below 2 and scar evaluations below 3. Conclusion: Improving the concealed position of the incision inside the tragus and achieving good results in the reduction of the temporomandibular joint disc is a widely applicable surgical approach for temporomandibular joint disc anchoring.

Objective: To retrospectively analyze the clinical data of maxillofacial chainsaw injuries, and provide the basis for the prevention and treatment of maxillofacial chainsaw injury. Methods: Seven patients with maxillofacial trauma caused by chainsaw that visited the Emergency Department of West China Hospital of Stomatology, Sichuan University from Jan 2022 to Jan 2023 were included. Demographic information, wound variables, treatments, and postoperative healing characteristics were collected to analyze the pathogenesis and summarize the treatment experience of maxillofacial chainsaw injury. Results: All patients underwent first-stage debridement and suture within 10 hours after injuries, among which 77.78% (7/9) of them underwent debridement and suture within 6 hours after injuries. The health education and wound nursing management were conducted postoperatively. Post-treatment wound healing was satisficed in 6 patients, while one patient had permanent right eye blindness, and one patient suffered wound infection after treatment, Conclusion: Multidimensional prevention strategies should be established to standardize the practice behavior of chainsaw and reduce the incidence of maxillofacial trauma caused by chainsaw. Came to an emergency, medical staffs and patients should take active measures to reduce the incidence of postoperative vital organ function impairment and complications.

Objective: To discuss the clinical and pathological features, differential diagnosis, treatment and prognosis of low-grade myofibroblastic sarcoma (LGMS), and report a case of LGMS that occurs in children's mandibular gingiva to raise awareness of this disease among clinicians. Methods: Analyze the clinical data, treatment, and pathological result of a child with LGMS in the right mandibular gingiva with jaw destruction, and the relevant LGMS at home and abroad were analyzed and summarized. Results: Due to a painless mass in the right mandibular gingiva, the patient came to hospital for surgical treatment, and the pathological result was gingival tumor. Recurrence occurred two weeks after surgery, so we did the second enlargement surgery, and the pathological result was LGMS. Conclusion: LGMS is a rare tumor derived from mesenchymal tissue, which tends to occur in the oral cavity and has no obvious clinically specific symptoms. It requires histopathological examination to confirm the diagnosis, and it should be distinguished from diseases such as inflammatory myofibroblastic tumor and leiomyosarcoma. Surgical enlargement is usually used clinically and the patient should be followed up for a long time.

Objective: To analyze the factors influencing labial bone resorption six months after delayed implant placement with simultaneous guided bone regeneration (GBR) in the anterior maxillary region. To explore the impact of the labial bone width at the time of second-stage surgery on marginal bone loss, 1 year after final restoration. Methods: The retrospective cohort study included 57 patients with 94 implants and with a follow-up of 1 year after final restoration. Cone beam CT (CBCT) was used to measure the labial horizontal bone width and vertical bone height of implants immediately after surgery (T1) and six months later (T2). Generalized linear mixed models were employed to analyze the factors affecting horizontal and vertical bone resorption. Implants were categorized into three groups based on labial bone width measured by CBCT six months postoperatively: 0 mm bone wall group, <2 mm bone wall group, and ≥2 mm bone wall group respectively. The impact of labial bone width on marginal bone resorption was explored through one-year follow-up after prosthetic loading. Results: Non-contained defects and implant connection with healing abutments were correlated with less horizontal and vertical bone resorption. Results from the one-year follow-up revealed that there was no significant difference among the three groups. Soft tissue augmentation at implant sites were significantly associated with less marginal bone loss. Conclusion: Six months after GBR, the use of healing abutments and contained defects intraoperatively favored the preservation of horizontal and vertical bone volume. Soft tissue augmentation at implant sites contributed to maintaining stable marginal bone level.

Objective: To evaluate the treatment outcomes of mandibular condyle fractures managed by surgical and conservative procedures based on new classification. Methods: A total of 45 patients with 57 condyle fractures who were referred to Department of Stomatology in Suzhou Hospital, Affiliated Hospital of Medical School Nanjing University and Suzhou Kowloon Hospital from January 2012 to December 2021 were retrospected. The data were related to causes of injury, fracture classification, treatment methods, complications, and follow-up results. These data were then analyzed. Results: There were 11 females and 34 males, with an average age of 34.67 years (16-76 years). Traffic accidents were the main cause of injury (56%). There were 26 cases (35 sides) of intracapsular condyle head fractures. Among them, there were 13 cases (13 sides) of type A, 7 cases (11 sides) of type B, 1 case (1 side) of type C, 3 cases (6 sides) of type M and 2 cases (4 sides) of no displacement. There were also 12 cases (13 sides) of condylar neck fractures, and 7 cases (9 sides) of condyle base fractures. Ten cases of condylar head fractures including 4 cases of type B, 1 case of type C, 3 cases of type M and 2 cases of no displacement, and 3 cases of condylar neck fractures. Thirteen cases were treated conservatively. Sixteen cases of condylar head fractures including 13 cases of type A and 3 cases of type B, 9 cases of condylar neck fractures and 7 cases of condyle base fractures (a total of 32 cases) were treated surgically. Five patients were lost to follow-up, forty patients had follow-ups over 6 months. There were 3 cases of pain, 1 case of TMJ clicking, and 1 case of limited mouth opening in conservative treatments group. Postoperative complications showed 1 case of condyle resorption and 2 cases of facial nerve injury. Conclusion: Mandibular condyle fractuers should be considered in combinantion with new fracture classification and patient's general condition, and a reasonable individualized treatment plan should be selected.

Objective: To explore the efficacy of concentrated growth factor (CGF) in promoting wound healing after extraction of mandibular impacted third molar and its influences on distal osseous defect depth (ODD) of second molar, clinical attachment level (CAL) and pain stress indexes. Methods: A total of 96 patients undergoing extraction of mandibular impacted third molar in the hospital between January and December 2022 were enrolled. According to random number table method, they were divided into research group (n=48) and control group (n=48). After extraction, control group was not given any implant, while research group was given CGF congelation. The postoperative scores of visual analogue scale (VAS), degree of facial swelling, contents of pain stress indexes [5-hydroxytryptamine (5-HT), galactosamine (Gal), calcitonin gene-related peptide (CGRP)], ODD, CAL and postoperative quality of life [postoperative symptom severity scale (PoSSe)] were compared between the two groups. Results: At 1 d, and 3 d after surgery, VAS scores in research group were (3.72±0.56) and (2.94±0.43) points, significantly lower than those in control group [(4.81±0.61), (3.86±0.57) points; P<0.001]. After surgery, degree of facial swelling in research group was milder than that in control group [(2.79±0.64) mm vs (5.46±1.22) mm, P<0.001]. At 3 d after surgery, the levels of 5-HT, Gal and CGRP were increased in both groups, which were lower in research group than those before surgery [(2.46±0.68) ng/mL, (9.56±1.42) nmol/mL, (1.76±0.52) ng/mL vs (3.15±0.46) ng/mL, (13.19±1.08) nmol/mL, (2.89±0.44) ng/mL; P<0.001]. At 6 months after surgery, the levels of ODD and CAL were lower than those at one week after surgery in both groups, which were lower in research group than control group [(4.21±0.87), (0.48±0.12) mm vs (5.75±0.61), (0.73±0.19) mm; P<0.001]. PoSSe scores in research group were lower than those in control group (P<0.01). Conclusion: CGF can reduce levels of pain stress indexes after extraction of mandibular impacted third molar, relieve pain and facial swelling, and improve postoperative quality of life in patients.

Objective: To explore the feasibility of extraction of mandibular third molars with cystic lesions under the guidance of a dynamic navigation system (DNS).Methods: Retrospectively analyzed hospitalized patients with lower impacted mandibular third molars in Hospital of Stomatology, Xi'an Jiaotong University from December 15, 2022 to April 15, 2023. According to the inclusion criteria, seven patients with the complex mandibular third molars accompanied cystic lesions, which was tightly adjacent to the inferior alveolar canal were included. All the CT imaging data were imported into the DNS and completed the navigation design. Then the molar were extracted, and cyst was removed under the guidance of navigation. The surgical condition and postoperative recovery state were further analyzed, focusing on the symptoms of postoperative inferior alveolar nerve injury (IANI). Results: All patients' wounds healed uneventfully with the application of DNS and the patients had no symptoms of IANI. Conclusion: The DNS technology determines the operation position in real time, which reduces the damage of the inferior alveolar neural canal and reduces the risk of inferior alveolar nerve damage.

The impact of mechanical force stimulation on bone metabolism is currently garnering significant scholarly interest. As scientific inquiry progresses, the focus of these studies has increasingly shifted towards a more granular level of analysis. Recent years, researchers are now examining this phenomenon from various perspectives, including the influence of differing mechanical properties, force magnitudes, frequencies, cell types, and underlying molecular mechanisms on bone metabolism. Given the intricate nature of this process, this article seeks to provide a comprehensive overview of the advancements in research pertaining to the modulation of bone metabolism through the alteration of mechanical stimuli or the targeting of specific cell types and receptors, in order to provide a reference for further research.

Objective: To investigate the effect of fibular free flap on reconstruction of postoperative defects after radiation-induced bilateral osteoradionecrosis of the jaw (ORNJ). Methods: Seven patients with radiation ORNJ who were referrd to Department of Oral and Maxillofacial Surgery in our hospital from January 2010 to November 2020 were retrospected. Among the cases, 6 males and 1 female, aged 42 to 56 years old, were included. All patients had primary nasopharyngeal carcinoma, and recurrent nasopharyngeal carcinoma was excluded. Fibular free flap was used to reconstruct bilateral osteoradionecrosis of the mandible. The fibular osteotomy and tissue flap survival, complications in donor and recipient areas, and postoperative mouth opening were evaluated for reconstruction outcomes. Results: After 10 to 30 months of follow-up, free fibular composite flap was successfully used to reconstruct mandibular defects. Facial artery was selected in 5 cases, superior thyroid artery in 2 cases, and end-to-side anastomosis of internal jugular vein was performed in all recipient veins. One patient developed venous crisis 6 hours after surgery. Emergency surgical exploration revealed that the vein was twisted during end-to-side anastomosis and recovered well after re-anastomosis. The harvested fibula was 17.5-21.0 cm in length. No patient had serious donor or recipient site complications. All patients had satisfactory facial shape, remaining normal occlusion, and mouth opening was 2.5-3.3 cm. Conclusion: Fibular myocutaneous flap can reconstruct the bilateral mandibular soft and hard tissue defects after radiation in patients with ORNJ, which is worthy of clinical application.

As a tissue engineering restorative material, hydrogel possesses outstanding biocompatibility, degradability and plasticity. Due to the lack of appropriate pore characteristics, the proliferation, migration and angiogenesis of cells inside and outside the gel are limited, which seriously affect the results of tissue engineering. Therefore, the preparation of macroporous structure has become a research focus on modification of hydrogel. In this paper, the effect of pore characteristics on biological behavior of scaffolds and the prepared methods of macroporous structure in recent years are reviewed.

Gingival amyloidosis represents the deposition of amyloid substances within the gingiva. This article reports a case of gingival amyloidosis treated at our hospital, discussing its clinical presentation, imaging characteristics, pathological features, treatment, and prognosis, with the aim of providing clinical physicians with insights and treatment guidelines for the disease.

Objective: To compare the distribution characteristics of biochemical stress on two techniques of zygomatic implant (ZI), sinus slot (SS) and extra sinus (ES), in combination with conventional implants respectively, and to provide theoretical basis for functional restoration of severe atrophic maxilla.Methods: Finite element analysis (FEA) models were constituted based on high-resolution computed tomography (CT) scanning data of a patient. ZIs were virtually placed into models with SS or ES techniques combined with two or four conventional implants. The von Mises stress values in implants and the principal stress values in alveolar bone were analyzed. Results: The highest von Mises stress was in the configuration of 2 conventional implants and 2 ZIs with ES technique (292 MPa). The lowest von Mises stress level in ZIs was in the configuration of 4 conventional implants and 2 ZIs with the SS technique (184 MPa). The highest maximum principal stress was in the configuration of 2 conventional implants and 2 ZIs with SS technique (31 MPa). The lowest maximum principal stress was in the configuration of 4 conventional implants and 2 ZIs with ES technique (12 MPa). The lowest minimum principal stress was in the configuration of 4 conventional implants and 2 ZIs with the SS technique (|-58| MPa). The highest minimum principal stress value in bone was in the configuration of 2 conventional implants and 2 ZIs with ES technique (|-81| MPa). Conclusion: Two ZIs with the SS technique and four conventional implants may be biomechanically safer for the rehabilitation of severe atrophic maxilla.

Objective: To explore the role and mechanism of fibroblast growth factor 13 (FGF13) in the repair of inferior alveolar nerve injury.Methods: To establish the model of inferior alveolar nerve injury in SD (Sprague-Dawley) rats. RNA from inferior alveolar tissue samples was collected 1, 3, 7 days after injury. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to detect the transcription expression levels of FGF13 gene at different time points after injury. Primary trigeminal nerve cells of neonatal SD mice were extracted and divided into experimental group and control group, transfected with FGF13 overexpressed plasmid and control plasmid, respectively. 3 days after successful transfection, cell RNA was extracted to detect the gene expression level of neurotrophin by RT-qPCR. Trigeminal nerve cells were stained with Neun and βⅢ-Tubulin nerve immunofluorescence, and the axon length of nerve cells was observed by laser scanning confocal microscope. ND7/23 nerve cells were divided into overexpression group (ND7/23-FGF13) and control group (ND7/23-vector), transfected with FGF13 overexpression lentivirus and control virus, respectively. Stable transmutation strains were screened out by purinomycin, and FGF13 protein immunofluorescence staining and JC-1 mitochondrial membrane potential fluorescence probe staining were performed. Extract cell RNA, then RT-qPCR was used to detect the expression of mitophagy related genes. Results: The expression level of FGF13 was significantly increased at 1 day after inferior alveolar nerve injury, decreased at 3 days after injury, and decreased to an equivalent level to the control group at 7 days after injury. Compared with the control group, the expression of FGF13, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and other factors increased in the experimental group. In the lentivirus overexpression group, FGF13 protein was more densely distributed in the nucleus, mitochondrial membrane potential was significantly increased, and the expression of mitochondrial autophagy related genes was increased. Conclusion: After inferior alveolar nerve injury, the expression level of FGF13 is transiently increased, which may have potential significance for the repair process of inferior alveolar nerve. Overexpression of FGF13 in trigeminal nerve cells can promote axonal elongation of nerve cells. The underlying mechanism may be related to the regulation of mitochondrial function and the promotion of mitochondrial homeostasis.

Objective: To explore the neural differentiation of adipose-derived stem cells (ASCs) induced by neural-induced conditional medium in vitro, and to study the optimal concentration of forskolin and the effect of optimal concentration on neurogenic differentiation of ASCs in vitro. Methods: ASCs were isolated by enzyme digestion method. The phenotype and differentiation ability of stem cells are identified by flow cytometry and cell staining. Nerve induction differentiation was performed in vitro by neural-induced conditional medium containing different concentrations of forskolin, and the optimal concentration was screened by immunofluorescence staining. ASCs were induced by neural-induced conditional medium containing the optimal concentration of forskolin and the morphological changes of cells were observed by microscope before induction, 6 h after induction and 24 h after induction. Effects of induction on rat ASCs were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR) and immunofluorescence. Results: The optimal concentration of forskolin in neural-induced conditional medium was 10 μmol/L, and the cells induced by neural-induced conditional medium containing 10 μmol/L forskolin could rapidly induce ASCs to differentiate in the direction of nerve formation. After induction, the cell morphology was similar to nerve cells. Results of RT-qPCR and immunofluorescence indicated that the expressions of anti-class Ⅲ β-tubulin (Tuj1), neurofilament-M (NF-M), nestin and S100 β at the mRNA level and protein level were increased after induction (P<0.05). Conclusion: Nerve differentiation of ASCs can be induced by conditional medium containing 10 μmol/L forskolin, and the induced cells are expected to become seed cells of facial nerve conduits.