Benign condylar hyperplasia is one of the causes of mandibular lateral deformity, it is easily to be misdiagnosed clinically and leads to the treatment failure. This article will elaborate the etiology and clinical features of benign condylar hyperplasia, as well as the diagnostic points and treatment progress, based on the literature and the clinical experience of our research group, to provide evidence-based medical evidence for the standardized clinical treatment of benign condylar hyperplasia. The etiology of benign condylar hypertrophy includes neurotrophic disorders, local circulatory disorders, traumatic injuries (especially condylar injuries that occur in childhood), unilateral mastication, temporomandibular arthritis, endocrine disorders, condylar osteoma, and heredity. Benign condylar hypertrophy is insidious, and occurs most frequently in individuals 10-30 years old, and the course of disease can last for many years. Its clinical characteristics are slow progressive facial asymmetry. Radionuclide bone scans have become the basis for the diagnosis and differential diagnosis of and treatment planning for benign condylar hypertrophy. Different treatment plans for active and inactive periods need to be developed, including close observation, proportional condylar resection and orthognathic surgery.

Alveolar bone is an important anatomic basis for implant-supported denture restoration, and its different degrees of defects determine the choices of bone augmentation surgeries. Therefore, the reconstruction of alveolar bone defects is an important technology in the clinical practice of implant restoration. However, the final reconstructive effect of bone quality, bone quantity and bone morphology is affected by many factors. Clinicians need to master the standardized diagnosis and treatment principles and methods to improve the treatment effect and achieve the goal of both aesthetic and functional reconstruction of both jaws. Based on the current clinical experience of domestic experts and the relevant academic guidelines of foreign counterparts, this expert consensus systematically and comprehensively summarized the augmentation strategies of alveolar bone defects from two aspects: the classification of alveolar bone defects and the appropriate selection of bone augmentation surgeries. The following consensus are reached: alveolar bone defects can be divided into five types (Ⅰ-0, Ⅰ-Ⅰ, Ⅱ-0, Ⅱ-Ⅰ and Ⅱ-Ⅱ) according to the relationship between alveolar bone defects and the expected position of dental implants. A typeⅠ-0 bone defect is a bone defect on one side of the alveolar bone that does not exceed 50% of the expected implant length, and there is no obvious defect on the other side; guided bone regeneration with simultaneous implant implantation is preferred. Type Ⅰ-Ⅰ bone defects refer to bone defects on both sides of alveolar bone those do not exceed 50% of the expected implant length; the first choice is autologous bone block onlay grafting for bone increments with staged implant placement or transcrestal sinus floor elevation with simultaneous implant implantation. Type Ⅱ-0 bone defects show that the bone defect on one side of alveolar bone exceeds 50% of the expected implant length, and there’s no obvious defect on the other side; autologous bone block onlay grafting (thickness ≤ 4 mm) or alveolar ridge splitting (thickness > 4 mm) is preferred for bone augmentation with staged implant placement. Type Ⅱ-Ⅰ bone defects indicate that the bone plate defect on one side exceeds 50% of the expected implant length and the bone defect on the other side does not exceed 50% of the expected implant length; autologous bone block onlay grafting or tenting techniques is preferred for bone increments with staged implant implantation. Type Ⅱ-Ⅱ bone defects are bone plates on both sides of alveolar bone those exceed 50% of the expected implant length; guided bone regeneration with rigid mesh or maxillary sinus floor elevation or cortical autologous bone tenting is preferred for bone increments with staged implant implantation. This consensus will provide clinical physicians with appropriate augmentation strategies for alveolar bone defects.

Objective To study the changes in levels of interleukin (IL)-6, IL-10, tumor necrosis factor-alpha (TNF-α), and alkaline phosphatase (ALP) in the gingival crevicular fluid (GCF) of patients with severe chronic periodontitis before and after nonsurgical periodontal therapy and to explore the relationship among the levels of these four biomarkers in GCF, their periodontal status and their clinical significance to evaluate the effect of nonsurgical periodontal therapy and periodontitis activity. Methods In total, 30 patients with severe chronic periodontitis were enrolled in a 1-year longitudinal pilot study (Chinese Clinical Trial Registry: ChiCTR-OCH-13004679). At baseline and 1, 3, 6, and 12 months after nonsurgical therapy, the periodontal clinical indicators plaque index (PLI), probing depth (PD), clinical attachment loss (CAL), sulcus bleeding index (SBI) were recorded. Filter paper strips were used to collect two deep-pocket (probing depth ≥ 6 mm) and two shallow-pocket (probing depth ≤ 4 mm) periodontal sites for each patient and weighed. The levels of interleukin IL-6, IL-10, TNF-α, and ALP in GCF were assessed using enzyme-linked immunosorbent assay. Meanwhile, 30 healthy sites of 15 subjects with healthy periodontium were used as the baseline controls for patients with severe chronic periodontitis. Results At the baseline, the TNF-α, ALP and IL-6 levels in GCF of the disease sites of patients with periodontitis were significantly higher than those in healthy periodontal sites of the control group (P < 0.001), and the levels of IL-10 were significantly lower than those in the control group (P < 0.001). In patients with severe chronic periodontitis, the levels of TNF-α, ALP and IL-6 in GCF at deep-pocket sites were significantly higher than those at shallow-pocket sites (P <0.001), and the IL-10 levels were significantly lower than those at shallow-pocket sites (P < 0.001). 1, 3, 6, and 12 months after nonsurgical treatment, the levels of TNF-α and ALP in GCF at the shallow- and deep-pocket sites in patients with chronic periodontitis significantly decreased, the level of IL-10 significantly increased (P < 0.005), and the level of IL-6 in GCF at the deep-pocket sites significantly decreased (P < 0.005). However, there was no significant difference in IL-6 level at shallow-pocket sites (P > 0.05). 1, 3, 6, and 12 months after nonsurgical treatment, the periodontal clinical indicators were improved compared with the baseline. In addition, there was a significant correlation between the levels of these four biomarkers and the periodontal clinical parameters (P < 0.05). During the two follow-up visits after nonsurgical periodontal therapy, the sites with more than 2-mm increase in attachment loss had significant differences in the levels of the four biomarkers in the GCF compared with the previous visit time (P < 0.005). Conclusion The detection of the levels of these four biomarkers in GCF has strong clinical significance for assessing the severity of periodontitis and the efficacy of nonsurgical periodontal therapy. Increased levels of TNF-α, ALP, and IL-6 and decreased IL-10 levels in GCF may indicate periodontitis progression at this site.

The most common periodontal biotype in the Chinese population is thin, which obviously limits orthodontic tooth movement. Periodontally accelerated osteogenic orthodontics (PAOO) can not only accelerate tooth movement through corticotomy but also expand the range of orthodontic tooth movement by alveolar bone augmentation, which could reduce the periodontal complications of orthodontic therapy. The development of PAOO has gone through a long and tortuous historical process over more than 100 years: from osteotomy based on "bony block movement" at the beginning to cortical osteotomy based on "the regional acceleratory phenomenon" and then to PAOO based on "bone tissue engineering". Throughout its development history, the understanding of the biological basis determines the development of the clinical technology. Therefore, PAOO should be based on basic research. Both the present clinical practice and future surgical improvements should be based on the fundamentals of bone repair and regeneration. According to the current evidence, it is suggested that piezocision and laser-assisted flapless corticotomy should be chosen only for simple cortical osteotomy, and surgical navigation technology or 3D-printed surgical guides are recommended. When a large amount of bone augmentation is needed, PAOO with an intact flap is still the first choice. A stable and infection-free healing environment is the key to wound healing; therefore, in addition to infection control, the surgical area should also be protected from external forces. At present, there are few high-quality clinical studies on PAOO. Multicenter, large-sample, randomized controlled clinical trials are needed to evaluate the clinical efficacy of different PAOO techniques in the future. The present article introduces the development history, fundamentals and operation precautions of PAOO, and a new perspective is also proposed, which may provide a reference for clinical practice.

Guided bone regeneration technology applied in alveolar bone defect regeneration is based on the barrier function and space maintenance of the barrier membrane. Therefore, traditional development strategies for barrier membranes focus on their physical barrier function, degradation characteristics and biocompatibility to avoid immunogenicity. However, not only does the barrier membrane passively block connective tissue, it is recognized as a “foreign body”that triggers a persistent host immune response, known as a foreign body reaction. The theories of osteoimmunology reveal a close relationship between the immune system and bone system and emphasize the role of immune cells in bone tissue-related pathophysiological processes. Based on these findings, we propose a novel development strategy for barrier membranes based on immune microenvironment regulation: by manipulating mechanical properties, surface properties and physiochemical properties, barrier membranes are endowed with an improved immunomodulation ability, which helps to regulate immune cell reactions to induce a favorable local immune microenvironment, thus coordinating osteogenesis and osteoclastogenesis as well as barrier membrane degradation to increase the efficiency of barrier membranes in GBR applications. In this paper, we review the development of barrier membranes and their close relationship to the immune microenvironment concerning bone regeneration and membrane degradation. Additionally, the outcomes of research on barrier membranes based on the regulation of the immune microenvironment have been summarized to improve the osteogenesis efficiency of barrier membranes and solve the problem of the regeneration and repair of bone defects, especially alveolar bone defects.

With the arrival of the era of big data, increasing attention has been drawn to the application of artificial intelligence (AI) in the medical field. AI has many advantages, such as objectivity, accuracy, minimal invasiveness, time savings and high efficiency. Therefore, the combination of AI with dental diagnosis and treatment can help dentists improve work efficiency and save medical resources, offering potential significant benefits for dental application. At present, AI has been gradually integrated into prosthodontics, oral and maxillofacial surgery, orthodontics, endodontics and periodontics. The AI system can realize automatic tooth preparation, automatic tooth arrangement and implantology. Deep learning can be used to assist in diagnosing maxillary sinus inflammation, predicting the complications of tooth extraction and improving the accuracy of osteotomy. The AI system can also provide significant clues for the diagnosis, treatment and prognosis of oral and maxillofacial tumors. The breakthrough brought by AI in cephalometric and the assessment of facial attractiveness of patients has promoted the development of intelligent and personalized orthodontic treatment. Deep learning and analysis of medical images also promote the accuracy of root canal therapy as well as the diagnosis and treatment of periodontal diseases. AI technology has realized the leap from digitalization to automation and intelligence in oral diagnosis and treatment, and its application potential in the oral field should not be underestimated. Based on the concepts of AI, this paper will focus on the application of artificial intelligence in various oral clinical fields and briefly introduce its advantages, problems and future.

Objective To investigate the clinicopathological features, treatment and prognosis of oralmucosal malignant melanoma to provide a reference for clinical practice. Methods Data from 19 patients with oralmucosal malignant melanoma were collected, and their clinical manifestations, treatment methods and follow-up results were retrospectively analyzed. Results Among the 19 patients, 11 cases (58%) had lesions in the gingiva, 7 cases (37%) had lesions in the palate, and 1 case (5%) had lesions in the tongue, the difference was statistically significant (P<0.05). Eight patients had regional lymph node metastasis with a metastasis rate of 42%, of which 4 cases had multiple site metastasis, and the total number of regional lymph node metastasis sites was 15. Among the 19 patients, 3 cases received only surgery, 4 cases received cryotherapy, and 12 cases received combined surgery, cryotherapy and biological immunotherapy. Pathological examination showed malignant melanoma. The positive rates of S-100, HMB-45 and Melan-A were 95%, 89% and 84%, respectively. Kaplan-Meier survival analysis showed that patients with lesions less than 5 cm² had a higher survival rate (P < 0.05). Conclusions Oral malignant melanomas usually present as black lesions in the oral mucosa, which are prone to metastasis in early stage. The area of lesions may affect the prognosis of the disease. Therefore, the large range of black lesions or masses should be the alert for the clinicians. Oral malignant melanoma patients are usually treated with combined treatment with surgery, cryotherapy and biological immunotherapy.

Mesenchymal stem cells (MSCs) are capable of self-replication and multi-directional differentiation, which are very important for the development and reconstruction of mesenchymal tissue. Bone tissue damage repair involves the participation of various cells and molecules. The recovery of bone mass requires sufficiently many MSCs to migrate to the damaged site to perform the reconstruction function. The local inflammatory response at the injury site can recruit MSCs and promote new bone formation. Simultaneously, niche changes during the migration of MSCs will affect their biological performance and initiate the phase of directed differentiation. This article explores the relevant mechanisms that mediate the migration of MSCs in the process of bone injury repair, including the regulation of immune cells and chemotactic signaling molecules in the inflammatory response in the bone repair stage through signaling pathways such as BMP/Smads. Then, it summarizes the mechanism by which the high matrix stiffness upregulates the expression of the integrin and focal adhesions to promote the MSCs migration and osteogenic differentiation. Simultaneously, the migration ability of MSCs can be regulated through drugs or genetic modification to promote the bone injury repair. The improvement of MSCs migration ability can shorten the time of bone tissue damage repair and improve the bone quality. This article reviews the role of the MSCs migration ability in bone tissue injury repair to provide a reference for the application of MSCs with high migration ability in the fields of stem cell therapy for bone related diseases and bone tissue engineering.

The reconstruction effect of peri-implantitis bone defects depends on their morphological characteristics. This paper reviews the morphological classification and treatment of peri-implantitis bone defects. A literature review shows that the morphological classification of bone defects in peri-implantitis includes morphology classification and clinical classification. At present, the Renvert classification is more commonly used in the clinic and is divided into four-wall bone pockets, three-wall bone pockets, two-wall bone pockets, one-wall bone pocket and dehiscence according to the number of bone walls. This has guiding significance in the treatment plan of peri-implantitis. The treatment of peri-implantitis depends on the severity of peri-implant bone defects. Peri-implantitis with mild bone defects is treated by nonsurgical treatment, peri-implantitis with severe bone defects is recommended to remove the implant, and peri-implantitis with moderate bone defects is further judged according to the shape of the bone defects. Four-wall bone pockets, three-wall bone pockets and dehiscence are mostly treated by bone regenerative surgery. For shallow two-wall bone pockets, one-wall bone pockets and horizontal bone resorption, bone resection is often used. However, most peri-implantitis has a variety of bone defect forms at the same time, which need to be treated with bone regenerative surgery and bone resection surgery.

The facial submental artery island flap (FSAIF) is a fasciocutaneous flap supplied by the facial submental artery. It is in close proximity with many oral and maxillofacial regions, and its tex ture and color are similar to those of the head and face. The flap has a constant and sufficient blood supply, and it is easy to prepare and has high survival rates and few complications. According to the tissue carried, FSAIF can be divided into fasciocutaneous flaps, myocutaneous flaps and simple flaps. The flap can also be made into an osteofasciocutaneous (myocutaneous) flap with a mandible to repair maxillary defects. Because this flap is a pedicled flap, it can greatly shorten the operation time, bed rest time and hospitalization time and has been widely used in repairing medium-sized defects of the oral and maxillofacial region. The indications for FSAIF in repairing maxillofacial defects should be strictly controlled. It can be safely used for benign or malignant tumors without cervical lymph node metastasis. For malignant tumors with cervical lymph node metastasis but without extranodal extension, the flap can be used on the premise of thorough neck dissection. The contraindication is cervical lymph node metastasis and extranodal extension of malignant tumors; therefore, other flaps should be selected for repair.

Hemangiomas and vascular malformations are common clinical diseases. According to their clinical and imaging characterizations, the International Society for the Study of Vascular Anomalies (ISSVA) has systematically classified infantile hemangioma and vascular malformations, and the classification has been widely recognized and applied. To date, most vascular malformations involve the following important signaling pathways: PI3K/Akt/mTOR and RAS/MAPK/ERK. This discovery has major impacts on the diagnosis and treatment of vascular malformations including the following: the understanding of the biology of vascular malformations has been increased; the understanding of vascular malformations based on genotype has been refined; and the development of targeted drugs for the treatment of vascular malformations has been promoted. Despite facing many challenges, with the development of gene sequencing, molecular biology and imaging technology, the relevance of vascular malformation classification and the accuracy of diagnosis are improving, and this is accompanied by innovations in surgical treatment and sclerotherapy, interventional embolization, and continuous progress in targeted therapy. At present, investigations on vascular malformations are mostly retrospective clinical studies or low-level clinical trials. The purpose of this paper is to review the literature on the treatment of infantile hemangioma, lymphatic malformation, venous malformation and arteriovenous malformation and to review the research progress in evidence-based treatment of infantile hemangioma and vascular malformation.

Exosomes are phospholipid bilayer vesicles secreted by living cells that can carry a variety of signaling molecules, such as RNA, DNA, protein, and lipids. Exosomes play a role in the transmission of signaling molecules between cells, thus regulating many physiological and pathological processes. The methods of extracting exosomes include differential centrifugation, density gradient centrifugation, exclusion chromatography, ultrafiltration, coprecipitation, polymer immune affinity, microfluidic separation technology, etc. Each of these extraction technologies has advantages and disadvantages; however, there is no unified international standard. In addition, the expression of specific proteins and genetic material of exosomes from different cell sources are different; thus, their expression characteristics and functions are also distinctive. Based on this situation, research on exosomes is limited to preclinical studies, and difficulties and challenges still exist in clinical application. This paper summarizes the progress of research in the field of exosomes, to understand the characteristics, modification and application of exosomes from different cell sources, and to summarize their advantages and disadvantages as well as challenges, which can help researchers better understand and master the performance of exosomes. Furthermore, improvement of standard procedures in the extraction and manufacturing of exosomes is important, as it will provide a reference for researchers to carry out exosome-related translational clinical research.

Ectopic eruption of the first permanent molar is a common malocclusion in the early stage of mixed dentition. The incidence among children aged 6-10 years is 0.83%-8.7%, with an increasing trend. The main manifestation is mesial impaction of the first permanent molar during eruption, which is accompanied by the loss of root resorption and space loss of the second primary molar. Ectopic eruption of the first permanent molars can lead to underdevelopment of the dental arch and severe crowding of the posterior dentition. Prevention and early intervention are very important. The ectopic eruption of the first permanent molar is related to the disruption of the differential growth and developmental balance among the teeth, alveolar bone and jaw. In clinical practice, the diagnosis can be made according to the patient's medical history and clinical and imaging examinations, and the treatment can be performed by dividing the teeth, dividing the distal slices of the second primary molars, and distally moving the first permanent molars. This paper reviews the incidence, etiology, clinical manifestations, risks of ectopic eruption of the first permanent molar, diagnostic methods, and common treatment options to provide references for clinical treatment.

Traumatic temporomandibular joint ankylosis refers to fibrous or bony fusion between the condyle and the glenoid fossa. It can cause problems with mouth-opening limitations, mastication difficulties, obstructive sleep apnea and hypopnea syndrome. When traumatic temporomandibular joint ankylosis occurs during childhood, it can cause facial asymmetry, micrognathia, and malocclusion, which significantly affect the physical and mental health. Once temporomandibular joint ankylosis occurs, it will be refractory and recurrent. The pathogenesis of temporomandibular joint ankylosis has not been completely elucidated and has always been a research hotspot in the oral and maxillofacial fields. In this paper, worldwide research was conducted, and the pathogenesis of traumatic temporomandibular joint ankylosis was clarified, such as “damage of condyle”,“disc displacement or rupture”,“damage to the glenoid fossa” and “lateral pterygoid muscle distraction”. The relative pathogenesis hypotheses were summarized, such as “hematoma organization” and “lateral pterygoid muscle distraction osteogenesis”. The related pathogenesis of traumatic temporomandibular joint ankylosis was discussed based on the latest cytology and molecular biology research.

Impacted teeth are a kind of complex malocclusion, and their incidence differs among different races, sexes and dental positions. The causes of impacted teeth include systemic factors and local factors, such as endocrine disorders, malnutrition, and acute and chronic infectious diseases. Local factors can cause abnormal tooth development or eruption during the process from tooth development to tooth eruption, such as damaged permanent tooth embryos caused by local inflammation or trauma, insufficient eruption space caused by premature loss of deciduous teeth, and eruption disorders caused by local lesions for example hyperplasia or odontoma. The clinical manifestation of impacted teeth is the absence of a permanent tooth in a normal position. We can use cone beam CT (CBCT) to locate the impacted teeth. Comprehensive orthodontic treatment includes surgical-assisted eruption, extraction of retained deciduous teeth or supernumerary teeth, removal of lesions such as odontomas and cysts, and expansion of the orthodontic space. When the dysfunctional local soft and hard tissues are removed during a surgical operation, the tooth still cannot sprout smoothly, and it needs to be assisted by orthodontic traction-guided eruption or extracted and autotransplantation. A clear diagnosis, evaluation of the difficulty of treatment and appropriate treatment are the keys to improving the success rate of treatment. In this paper, the epidemiology, etiology, diagnosis and corresponding treatment methods of impacted teeth will be reviewed, and the orthodontic treatment of impacted teeth will be comprehensively described to provide a reference for clinicians about the treatment of impacted teeth.

Benign tumors of the parotid gland are common tumors of the head and neck. Surgical resection is considered the main treatment. For the treatment of benign parotid tumors, different surgical approaches can be applied based on many factors, such as tumor type, size, location, depth of tumor and patient requirements, such as improved periauricular incision and improved facial wrinkle removal incision, to achieve the best therapeutic effect. In parotidectomy, the facial nerve, great auricular nerve and parotid duct should be protected as much as possible to preserve the function of the nerve and gland and reduce postoperative complications. In addition, complications after parotidectomy, such as facial nerve injury, salivary fistula, Frey syndrome, postoperative facial depression, abnormal ear sensation and recurrence, should be actively prevented and treated early after the operation, consequently minimizing the impact on patients' postoperative life and improving patients' satisfaction with the operation.

Tooth loss is accompanied by alveolar bone absorption or defect, resulting in insufficient bone and soft tissue. In addition to restoring the masticatory function of missing teeth, implant treatment should also needs to restore the contour and shape of the dental arch. Guided bone regeneration is a common means of bone increase. Xenogeneic granular bone substitute materials are widely used in the field of clinical bone augmentation due to their advantages of long degradation time and low immunogenicity, but other problems, such as inconvenient operation and low osteogenic activity, remain. Plasmatrix can effectively improve the effect of oral tissue regeneration and reduce the occurrence of postoperative complications, and its application in oral tissue regeneration is gradually increasing. This article first introduces the main application forms of plasmatrix in horizontal bone augmentation (mainly solid plasmatrix membrane and plasmatrix bone block), and reclassifies horizontal bone defects according to commonly used decision-making schemes in clinical bone augmentation, in other words, whether the implant can be placed in the ideal position and whether there is bone dehiscence after implantation. Type Ⅰ defects refers to the situation where the bone at the implant site can allow the insertion of an implant with ideal size, and there is no bone dehiscence around the implant, but the alveolar bone contour is not ideal; type Ⅱ defects refers to the situation that when an ideal size implant is placed at the implant site determined by the future prosthesis position, there will be bones on three sides of the implant, but there is bone dehiscence in the buccal bone wall (the length of bone dehiscence is less than 50% of the implant length); type Ⅲ defects refers to the situation where the bone volume at the implant site is not enough to for the placement of the ideal size implant at the ideal position, and bone grafting is required to restore the bone volume before the implant placement. The application of plasmatrix in different types of bone defects is then described. In type Ⅰ bone defects, the solid plasmatrix membrane is used instead of the collagen membrane; in type Ⅱ bone defects, the bone defect around the implant is filled by plasmatrix bone block and then covered with collagen membrane and solid plasmatrix membrane; and in type Ⅲ bone defects, plasmatrix bone block is used to replace autogenous bone block to fill the defect area, and titanium screws are used for fixation. The defect is then covered with a collagen membrane and a solid plasmatrix membrane. This article aims to provide oral clinicians with a comprehensive understanding of plasmatrix and simplify the guidelines for bone regeneration operations.

In recent years, artificial intelligence technology has developed rapidly and has been gradually applied to the fields of clinical image data processing, auxiliary diagnosis and prognosis evaluation. Research has shown that it can simplify doctors’ clinical tasks, quickly provide analysis and processing results, and has high accuracy. In terms of orthodontic diagnosis and treatment, artificial intelligence can assist in the rapid fixation of two-dimensional and three-dimensional cephalometric measurements. In addition, it is also widely used in the efficient processing and analysis of three-dimensional dental molds data, and shows considerable advantages in determining deciding whether orthodontic treatment needs tooth extraction, thus assisting in judging the stage of growth and development, orthodontic prognosis and aesthetic evaluation. Although the application of artificial intelligence technology is limited by the quantity and quality of training data, combining it with orthodontic clinical diagnosis and treatment can provide faster and more effective analysis and diagnosis and support more accurate diagnosis and treatment decisions. This paper reviews the current application of artificial intelligence technology in orthodontic diagnosis and treatment in the hope that orthodontists can rationally treat and use artificial intelligence technology in the clinic, and make artificial intelligence better serve orthodontic clinical diagnosis and treatment, so as to promote the further development of intelligent orthodontic diagnosis and treatment processes.

Objective To investigate the diagnosis, treatment and prognosis of lymphoepithelial carcinoma of the parotid gland. Methods Data from 22 patients with parotid lymphoepithelial carcinoma from 2012 to 2019 were collected, and their clinical manifestations, imaging examinations, treatment methods and follow-up results were retrospectively analyzed. Results Among the 22 patients, 8 were males and 14 were females. The patients ranged from 26 to 61 years old, with a complaint duration ranging from 3 days to 18 years. One patient had multiple unilateral lumps in the parotid gland, and the other 21 patients had single unilateral lumps in the parotid gland. All patients underwent preoperative spiral CT examination. CT showed a soft tissue lump in the parotid tissue, the internal density shadow was not uniform, the CT value ranged from 26 to 81 Hu, and 15 patients presented elliptical lesions with clear boundaries. Seven patients presented nodular lesions, and the boundary was not clear. The diagnosis of all cases was ultimately based on pathological examination. Hematoxylin-eosin (HE) staining images showed active epithelial cell growth with atypia, mitotic figures could be seen, and abundant lymphocyte and plasma cell infiltration could be seen in the tumor stroma. All 22 patients received surgical treatment; 9 patients did not undergo cervical lymph node dissection. Twenty patients received adjuvant radiotherapy after surgery, and 10 of them received adjuvant chemotherapy at the same time. One patient only received chemotherapy after surgery, and one patient did not receive any other adjuvant therapy after surgery. All patients received follow-up visits. One patient died of liver metastasis 16 months after the operation, and the remaining patients survived without tumors for periods of 13 months to 8 years until the present. Conclusion Parotid lymphoepithelial carcinoma is a rare malignant tumor clinically. Pathology is still the gold standard for the diagnosis of lymphoepithelial carcinoma of the parotid gland. Radical resection of the tumor is the first choice of treatment. Selective neck lymph node dissection and postoperative adjuvant radiotherapy and chemotherapy can obtain better therapeutic effects according to clinical examination, imaging examination and neck conditions.

Chronic obstructive diseases of the parotid gland are common clinically, with repeated swelling and a prolonged course and poor treatment outcomes. Based on the summarization of clinical practice and related literature, from the viewpoint of etiology, parotid obstructive diseases can be classified as mechanical obstructions, specific obstructions and non-specific obstructions. The principles of fluid mechanics are introduced to explain the formation of parotid obstructions. According to the different causes, the methods of changing the flow pattern of saliva in the parotid to reduce the resistance and relieve the obstruction, are proposed, such as mechanical factors removals, application of drugs that promote saliva secretion and lower saliva viscosity, ductal expansion under endoscopy and stent placement, and embolization of collateral ducts. These managements can effectively increase the salivary flow rate, reduce the occurrence of the saliva stranded and parotid gland obstructions.

Objective Systematic evaluation of the correlation of HLA-DQB1 and HLA-DRB1 allele polymorphisms with caries, to provide reference for caries prevention and treatment. Methods Relevant literature published before December 2020 was searched in the Cochrane Library, PubMed, Embase, Web of Science, Scopus, CNKI, Wanfang, VIP, and CBM databases. Meta-analysis was performed using the R4.0.2 software to test for heterogeneity and evaluate the publication bias. Results In total,10 case-control studies were included with 564 people in the case group and 676 people in the control group. The results of the Meta-analysis show that: ① HLA-DQB1*02 (OR=0.52, 95%CI=0.29-0.93, P < 0.05) and HLA-DRB1*09 (OR=0.34, 95%CI=0.21-0.58, P < 0.05) are protective factors of dental caries; ② HLA-DRB1*13 (OR=2.96, 95%CI=2.03-4.33, P < 0.05) and HLA-DRB1*14 (OR=1.95, 95%CI=1.26-3.02, P < 0.05) alleles are risk factors for the development of dental caries. The results of the subgroup analysis are: HLA-DRB1*07 is a caries susceptibility factor in the Chinese population (OR=0.48, 95% CI=0.24-0.97, P < 0.05), while it is not statistically significant in the Brazilian and Turkish populations; HLA-DRB1*11 is a caries protective factor in the saliva group (OR=2.26, 95% CI=1.46-3.52, P < 0.05). 3.52, P < 0.001), while it is a caries susceptibility factor in the blood group (OR=0.09, 95% CI=0.12-0.34, P < 0.001). Conclusion HLA-DRB1*13 and HLA-DRB1*14 alleles are caries susceptibility genes, and HLA-DQB1*02 and HLA-DRB1*09 have protective effects on the caries development. HLA-DRB1*07 is a caries susceptibility gene in the Chinese population; HLA-DRB1*11 is a caries protective gene in the saliva group. Due to the limited sample size and quality of the included studies, more high-quality studies will be included later for verification.

Objective To construct a hit-deficient mutant strain of S. mutans ATCC25175 and verify its cell cycle regulatory function. Method Genomic DNA was extracted from S. mutans ATCC25175 strains, and then the upstream and downstream DNA fragments of the hit gene were cloned into the pFW5 vector (spectinomycin resistant) to construct recombinant plasmids using PCR amplification. Third, employed by natural genetic transformation in S. mutans ATCC25175 strains, the linearized recombinant plasmids were transformed into their genetic competence, induced by the synthesized competence-stimulating peptide (CSP), and then, homologous recombination was utilized to produce crossover and noncrossover products. Fourth, the hit-deficient mutant strains of S. mutans ATCC25175 were screened through the spectinomycin-resistance marker and identified by the electrophoresis of PCR products and PCR Sanger sequencing. Finally, its growth rate in vegetative BHI medium was also investigated. Results The upstream (856 bp) and downstream (519 bp) DNA fragments of the hit gene from the genomic DNA materials of S. mutans ATCC25175 were cloned into two multiple cloning sites (MCS-I and MCS-II) of the pFW5 vector, respectively, and the recombinant plasmid pFW5_hit_Up_Down was constructed and identified by double-emzyme digestion and PCR Sanger sequencing. The linearized recombinant plasmids were transformed into their genetic competence, induced by the synthetic CSP, and then, homologous recombination was utilized to produce various products. The hit-deficient mutant strains of S. mutans ATCC25175 were screened through the spectinomycin resistance marker and identified by the electrophoresis of PCR products and Sanger sequencing. The growth rate of the hit-deficient mutant strains versus their parental S. mutans ATCC25175 strains was increased greatly (P<0.001). Conclusion The hit-deficient mutant strains of S. mutans ATCC25175, having heritable traits, were successfully constructed, and the encoding Hit protein is growth-phase regulated in the cell cycle.

Objective To investigate the antibacterial effect of a new photosensitizer, indocyanine green (ICG)-mediated photodynamic therapy, on a biofilm of Fusobacterium nucleatum (F. nucleatum) in vitro. Methods The biocompatibility of the photosensitizer ICG was detected by CCK8. F. nucleatum (10⁸ CFU/mL) was cultured in anaerobic conditions (80% N₂, 10% H₂ and 10% CO₂) mixed with the photosensitizer ICG at concentrations of 0, 10, 20, 30, and 40 μg/mL and then treated with antibacterial photodynamic therapy (808 nm near infrared light with an intensity of 0.1 W/cm² for 3 min), and a mature biofilm was formed after 2 days. The bacteriostatic effects of different concentrations of ICG on F. nucleatum biofilms were compared by colony formation unit count (CFU). The effect of ICG on the formation of F. nucleatum biofilms and biofilm metabolic activity was determined by crystal violet quantification and MTT assays. The effect of ICG on the formation of extracellular polysaccharides in F. nucleatum biofilms was determined by the phenol-sulfuric acid method. The change in the number of bacteria was observed by confocal microscopy. Results CFU and biomass of the biofilm gradually decreased with increasing ICG concentration, and there were significant differences compared with the control group. Meanwhile, the metabolic activity of the biofilm and the production of extracellular polysaccharides also showed a significant difference between the ICG groups and the control group (P<0.01). At the same time, laser confocal microscopy showed that the number of living bacteria decreased gradually. Conclusion Antibacterial photodynamic therapy with photosensitizer ICG can effectively inhibit the formation of F. nucleatum biofilms.

Gingival pigmentation(GP) manifests as dark pigmentation spots, such as black or brown spots, in the gums. It is mostly caused by the deposition of melanin particles secreted by melanocytes on the gingival epithelium. The influencing factors may be divided into two categories, exogenous and endogenous. Exogenous factors include heavy metals, tattoos, smoking or drug use, and endogenous factors are related to certain diseases. The clinical grading of GP helps make a reasonable assessment of the necessity of treatment and prognosis. The Dummett-Gupta oral pigmentation index is a commonly used grading method, and the new grading method formed by combining the etiology and clinical manifestations described the patient’s situation more comprehensively. It is necessary to ask for a detailed medical history, complete examination, and correctly differentiate between physiological GP and GP caused by pathological state. Laser treatment is the currenttreatment with a better treatment effect and higher patient acceptance, and it is more comfortable and convenient, including diode laser, Er: YAG laser, and Nd: YAG laser, etc. This article summarizes the formation factors, clinical manifestations and treatment methods of GP to provide ideas for the clinical diagnosis and treatment of GP.

Corona Virus Disease 2019 (Corona Virus Disease 2019,COVID-19) has become a public health emergency that has attracted global attention because of its large-scale outbreak resulting in numerous human infections and deaths. COVID-19 is a highly contagious respiratory disease caused by novel coronavirus 2019-nCoV. Due to a large number of infections and fast transmission speed, it's significant to diagnose the infected people quickly and detect the asymptomatic infected people as soon as possible. At present, the preliminary screening is judged by the clinical manifestations of the patients, mainly involving the respiratory system, but recent studies have found that the patients infected with COVID-19 have unique oral manifestations, such as taste disturbance, xerostomia, halitosis, inflammation of salivary glands, necrotizing periodontal disease and some of them are earlier than typical symptoms such as dry cough, fever, etc. Paying attention to the oral manifestations of patients can further improve the COVID-19 screening procedure. At present, symptomatic treatment is mainly used for these oral symptoms.

Objective To investigate the effects of apoptotic bodies (ABs) derived from dental pulp stem cells (DPSCs) on macrophage polarization and inflammation response in vivo. Methods Human DPSCs were extracted, cultured and identified. Staurosporine was used to apoptosis induction and differential methods were performed for ABs identification. The in vitro cultured macrophages were divided into 3 groups: solvent control, lipopolysaccharide (LPS), and the LPS+ABs. The macrophages were stimulated with LPS to induce inflammation followed by ABs treatment. In the untreated group, macrophages were added with an equal amount of solvent. The specific uptake of ABs by macrophages, the expression level of CD206 and the levels of inflammatory cytokines were analyzed. The mouse models of cutaneous wounds and dextran sulfate sodium (DSS)-induced colitis were established, and the mice were randomly divided into 3 groups: the PBS-treated group, the DPSCs-treated group, and the ABs-treated group. The mice were injected with the same volume of PBS, DPSCs and ABs, respectively. The body weight, histological pathology, the expression levels of CD206 and cytokines, and the extent of tissue regeneration were measured. Results DPSCs and ABs derived from DPSCs were successfully isolated and characterized. ABs could be taken up by macrophage. While lipopolysaccharide(LPS) induced production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), ABs significantly reduced the levels of these pro-inflammatory cytokines and increased the expression of transforming growth factor-β (TGF-β) and CD206 (P < 0.01). In the cutaneous inflammatory wound model, the wound closure rate in mice intravenously injected with ABs was significantly accelerated (P < 0.05). The administration of ABs markedly reduced the pro-inflammatory factors levels and increased the CD206⁺ cell number. In the colitis model, treatment with ABs markedly reduced the loss in bodyweight (P < 0.05), recovered the colon length (P < 0.01), and significantly increased the CD206⁺ cell number. Conclusion DPSCs-derived ABs could enhance macrophage M2 polarization and attenuate inflammation. Therefore, ABs could be used as a promising cell replacement for inflammatory regulation and tissue regeneration.

Objective To compare the clinical effect of the Yu flap and the Karapandzic flap in repairing greater than 2/3 defects of the lower lip and to provide a reference for clinical application. Methods Ten patients with greater than 2/3 lower lip defects after surgical resection of lower lip tumors and vascular malformations were enrolled: 5 patients were repaired with the Yu flap (Yu flap group) and 5 patients were repaired with the Karapandzic flap (Karapandzic flap group). Follow-up for at least 1 year was conducted to evaluate the morphology (symmetry, stoma, exposure of vermilion) and function (sensory function, motor function) of the reconstructed lower lip. Results All the flaps survived, and all wounds showed primary healing. The lower lips reconstructed with the Yu flap or the Karapandzic flap obtained similar satisfactory oral function. The sensory function was essentially restored. There were no obvious obstacles in speech and expression, and no saliva leakage occurred. In the Yu flap group, only 1 patient had slight microstomia. In the Karapandzic flap group, 2 patients had slight microstomia and 3 patients had moderate microstomia. 90% (9/10) of the patients were very satisfied with the postoperative outcome, and 1 patient in the Karapandzic flap group was basically satisfied. Conclusion Both the Yu flap and the Karapandzic flap can be used to repair greater than 2/3 lower lip defects and reliable outcomes can be achieved. These two methods can achieve similar oral functions, but the effect of the Karapandzic flap is inferior to that of the Yu flap in terms of aesthetic appearance, and microstomia often occurs, while the Yu flap can generally maintain the original size of the mouth cleft.

Objective Conebeam CT (CBCT) was used to measure the palatine between the maxillary first and second molars. The proximal and distal palatal widths of the maxillary first and second molar and the palatal mucosal thickness and bone tissue thickness when microscrew implant anchorage nail were implanted at different angles provided a reference for the clinical selection of microscrew implant placement. Methods The image data of 90 adult patients were selected as the research object, and the jaw bone was reconstructed by scanning. In maxillary palatine, selection of distances at 12 mm, 14 mm, 16 mm, and 18 mm from the palatal apex of maxillary first molar between the maxillary first and second molar were used as measurement, measured the proximal and distal palatal widths of maxillary first and second molar and the palatal mucosal thickness and bone tissue thickness when microscrew implant anchorage nails were implanted at 30 °, 45 °, 60 °, and 90 °. SPSS 26.0 software was used for one-way ANOVA and LSD pair comparison. Results The larger the angle of the microscrew implant anchorage nail was, the smaller the proximal and distal medial widths between the maxillary first and second molar, and the difference was statistically significant (P < 0.05). Compared with the 90° direction, the proximal and distal medial widths of the microscrew implant anchorage nail were larger in the 60° direction. The greater the angle of implantation, the smaller the mucosal thickness and the greater the bone tissue thickness, and the results showed a significant difference (P < 0.001). Compared with the direction of 30° and 45°, the mucosal thickness at the direction of 60° was smaller, and the bone tissue thickness was larger. The higher the position of the microscrew implant anchorage nail, the greater the width of the proximal and distal medial, and the difference was statistically significant (P < 0.05). Compared with the positions 12 and 14 mm from the palatal tip, the proximal and distal medial widths of the microscrew implant anchorage nail were larger. The higher the implant position was, the greater the mucosal thickness and the smaller the bone tissue thickness. The results showed a significant difference (P < 0.001). Compared with the position of 18 mm from the palatal tip of the maxillary first molar, the mucosal thickness was smaller and the bone tissue thickness was larger. Conclusion It is most appropriate to implant microscrew implant anchorage nail at least 10 mm in length in the direction of 60° at the palatal apex 16 mm from the maxillary first molar in palatine between the first and second molar.

Most salivary gland stones involve the submandibular gland, which often cause recurrent swelling and pain of the glands after meals, and used to be the main reasons for the gland removals. With the trend of minimally invasive treatment, gland preservation and functional recovery in the diagnosis and the treatment of submandibular lithiasis have been paid more and more attention. New equipment and technologies such as CBCT and sialendoscopy, which are widely used in clinical practice, have contributed a lot to the accurate orientation and minimally invasive treatment of stones, and enriched the managements of submandibular lithiasis. Based on our experience and the review of relevant literature, this paper attempts to summarize the treatment strategies for submandibular stones distributed in different parts of the duct: ① emphasizing on the integrity and functions of the organ; ② endoscopy and minimal invasiveness come first; ③ scientific classifications and personal managements. Appropriate treatment options should be selected according to the features of the stones: endoscopic lithotomy helps a lot in removing those located in the anterior or middle part of the duct; endoscopic lithotomy or/and sialolithotomy are needed according to the features of hilar stones; the regular follow-up is required for the intraglandular stones. Meanwhile, the evaluation of the gland function is also important. After the removals of sunmandibular stones, the functions of the glands should be promoted to restore as far as possible.

Objective To investigate the multi-disciplinary team (MDT) management in the treatment of giant neurofibroma in maxillofacial and neck region, to provide reference for clinical practice. Methods Retrospective analysis was conducted on the perioperative whole-process management process of 2 cases of giant neurofibroma in maxillofacial and neck region jointly formulated treatment plan by oral and maxillofacial surgery department with the assistance of the department of anesthesiology, ICU, vascular surgery, thoracic surgery, etc. Results MDT treatment process (anesthesia-embolization-collaborative surgery-ICU-post-operative management) of the two patients was smoothly conducted according to the pre-operative plan. There were no adverse events or accidents that were not predicted by the risk assessment from multiple teams during the operation, and no serious complications occurred after the operation. The post-operative pathological report of both cases was "neurofibroma". Wounds in both patients healed in stage I. The course of treatment was smooth, and the surgical treatment was completed without serious complications. Conclusion MDT management can play a positive role in the diagnosis and treatment of giant maxillofacial and neck neurofibroma so that patients can obtain safer and more effective diagnosis and treatment.

Ideal sutures can provide great fixation, wound closure and a stable environment for healing of the surgical site. Tension-free apposition sutures are important for tissue regeneration and could tackle insufficient amounts of soft and hard tissue, especially in missing tooth sites that require implantation. The internal horizontal mattress suture, similar to the conventional horizontal mattress suture, forms a rectangle that can be bisected by the incision with both intrusion and extrusion of the needle on each side. On the basis of the rectangle, the internal horizontal mattress suture emphasizes that the suture should be located below the incision, so the eversion of the wound margin is the highlight of this procedure. The internal horizontal mattress suture could stabilize the graft on the targeting tissue, realize the fixation of the collagen membrane, apically repositioned flap and soft tissue graft, reduce the tension on the incision, and further release the tension of the incision margin. Beyond the primary need for fixation and wound closure, internal horizontal mattress sutures can also achieve stress interruption that reduces the interference of the surrounding muscle and can better master wound tension with the assistance of interrupted sutures. Given the above advantages, horizontal internal mattress sutures have great potential in the application of implant-related regenerative surgery. In this review, according to our experience in clinical practice and the literature, we summarize the advantages of internal horizontal mattress sutures in tissue augmentation. In addition, the sites and sequence to insert the needle and the spatial relationship between the suture and incision are clarified with the rationale of the naming pattern, which is conducive to experience exchange and clinical practice.

The transpalatal arch (TPA) is widely used in clinical orthodontics for various purposes. This article reviews the versatile clinical uses and mechanics of TPAs for clinical reference. Traditionally, TPA is conceived as an anchorage reinforcement device. However, the literature does not support the sole use of TPA for anchorage control. TPA, combined with other conventional anchorage means, can only provide sufficient anchorage in certain cases. As an adjunct to fixed appliance treatment, TPA can be applied for arch width maintenance, tooth alignment and habit braking to improve treatment efficiency and reduce side effects. Meanwhile, TPA can be used to provide active orthodontic forces for maxillary molars to move or rotate bilaterally and unilaterally in all three planes of space, especially on occasions where molar rotation and transverse discrepancy exist. A two-couple system is formed with a TPA connecting bilateral maxillary first molars, the mechanical analysis of which can improve the understanding of treatment mechanics and make tooth movement more predictable. In recent years, TPA has also been used in combination with temporary anchorage devices for maxillary molar intrusion and full arch mesialization or distalization. The combined use of TPA with TADs and maxillary skeletal expanders could be further investigated in the future.

Objective To observe the root and root canal morphology of mandibular second molars in Western Guangxi by CBCT, to provide a reference for clinical diagnosis and treatment. Methods In total, 564 patients′ 1 128 mandibular second molars that satisfy the inclusion criteria were analyzed with a planmecaromexis CBCT machine and its own image analysis software. The patients′ gender, age and ethnic differences in the root and canal morphology and the symmetry of the bilateral root and canal were statistically analyzed. Results Among the 1 128 mandibular second molars, 662 were the Zhuang ethnic group and 384 were the Han ethnic group, and 82 were other ethnic groups; the double root type and C-shaped root type accounted for a relatively high proportion: 73.94% and 24.47%, respectively. The detection rates of the double root type were higher in males than in females (P < 0.05); the detection rates of the C-shaped root type were higher in females than in males (P <0.05); the root type of the teeth was mainly double-rooted in the Zhuang ethnic group (P<0.01). The incidence of type IV in the mesial root of the double root type mandibular second molar was the highest (P < 0.01), and the incidence of type I in the distal root was the highest (P < 0.01). The C-shaped root canal is more continuous at the mouth of the root canal, more downward corresponds to a worse continuity: in three different levels of root canal orifice, root middle and root apex, the root canal orifice is dominated by the C1 type, and both root middle and root apex are mainly C3-type (P < 0.01). The difference in symmetry of bilateral roots and root canals was statistically significant among different gender groups, age groups, and ethnic groups (P < 0.05): there were more males than females, the results in the 18-35-year-old group and the Zhuang ethnic group were higher. Conclusion The root and root canal morphology of mandibular second molars in western Guangxi people are complex and changeable. The roots are mainly double root type in the Han ethnic group and the Zhuang ethnic group. C-shaped roots are also common. The detection rate of C-shaped roots in the Zhuang ethnic group was higher, and the symmetry rate of bilateral roots and that of bilateral root canals was higher in the Zhuang ethnic group than in the Han ethnic group.

Objective To explore the potential mechanism of the main active component Tripterygium wilfordii in the treatment of oral lichen planus based on network pharmacology. Methods The components of Tripterygium wilfordii and targets were searched through the Traditional Chinese Medicine system pharmacology database and analysis platform (TCMSP) and the Traditional Chinese Medicine integrated database (TCMID) databases. The related targets of oral lichen planus (OLP) were obtained through databases such as Gene Cards. The OLP targets were mapped by Venn analysis to the targets of Tripterygium wilfordii to screen out the common targets as the treatment of OLP targets of Tripterygium wilfordii. The Cytoscape software and STRING were used to construct a chemical component-target network and protein-protein interaction network, a network analyzer was used to compute the network topology properties, a cluster profiler software was used to analyze the GO classification enrichment analysis and KEGG signal path analysis, and a Tripterygium wilfordii chemical components-targets-pathway network diagram was constructed. Results Twenty-three components and 44 OLP treatmenttargets of Tripterygium wilfordii were obtained. The key active ingredients of Tripterygium wilfordii in the treatment of OLP are triptolide, kaempferol, and tangerine peel. The key targets include TNF and AKT1. The GO classification enrichment analysis obtained 63 GO terms, which are mainly involved in the leukocyte differentiation and reaction to lipopolysaccharides. The KEGG analysis identified 111 signaling pathways, which are mainly related to the TNF signaling pathway and IL17 signaling pathway. Conclusion Based on the network pharmacology, this study preliminarily revealed themain components, targets and pathways of Tripterygium wilfordii in the treatment of OLP. This study can provide a theoretical basis for further research to explore drugs with high activity and low toxicity to treat OLP from Tripterygium wilfordii.

Objective To analyze the accuracy of the infiltrating depth of tongue squamous cell carcinoma measured by magnetic resonance imaging (MRI) using pathological sections under a light microscope to provide a clinical reference. Methods Seventy-three patients with tongue squamous cell carcinoma who visited the Department of Stomatology of the First Hospital of Shanxi Medical University and Xiangya Stomatological Hospital from January 2018 to September 2020 were selected. Preoperative MRI was performed to evaluate the infiltration depth of tongue squamous cell carcinoma, and intraoperative frozen pathological sections were used to confirm the infiltration depth of tongue squamous cell carcinoma measurement. Results The infiltration depth of tongue squamous cell carcinoma measured by T1-weighted imaging was 1.11 mm (95% CI=0.51-1.70; t=3.72; P < 0.001), and the correlation coefficient r was 0.95. The T2-weighted average overestimation was 2.17 mm (95% CI=1.32-3.02; t=5.10; P < 0.001), and the correlation coefficient was 0.92. The Bland-Altman plot showed good consistency between T1- and T2-weighted images and pathologic measurements. Conclusion The infiltration depth of tongue squamous cell carcinoma measured by MRI is more accurate, with an average overestimation of 1-2 mm compared with pathological measurements, and T1-weighted images are better than T2-weighted images.

Objective To explore the value of an oral squamous cell carcinoma (OSCC) diagnostic model constructed by using principal component analysis (PCA) to analyze a database of differentially expressed genes in OSCC and to provide a reference for clinical diagnosis and treatment. Methods RNA-seq expression data of OSCC and normal control samples were obtained from The Cancer Genome Atlas (TCGA) database, and then, normalized and differentially expressed genes (DEGs) were identified by R software. DEGs were enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis to identify their main biological characteristics. 70% of DEGs expression data in RNA-seq were randomly selected as the training set and 30% were selected as the test set. Then, the PCA method was applied to analyze the training set data and extract the principal components (PCs) related to the diagnosis of OSCC in order to construct a PCA model. Then, the receiver operating characteristic (ROC) curves of PCA models in the training set and the test set were respectively drawn, and the area under curve (AUC) was calculated to evaluate the accuracy of the PCA model in the diagnosis of OSCC. Results RNA-seq expression data of OSCC and normal control samples obtained from TCGA database included 330 samples and 32 samples, respectively. Using false discovery rate (FDR) <0.001 and |log2 fold change| (|log2FC|) >4 as the thresholds, a total of 159 downregulated and 248 upregulated DEGs were identified, which were mainly enriched in cellular components such as intermediate fiber and melanosomal membrane, pigment and salivation-related biological processes and mainly involved in salivary secretion and tyrosine metabolism pathways (P.adjust<0.05 and Q<0.05). The DEGs were proposed as tumor markers for OSCC, and PCA analysis of the training set showed that the cumulative ratio of variance of PC1, PC2 and PC3: [including submaxillary gland androgen regulated protein 3B (SMR3B), proline rich 27 (PRR27), histatin 3 (HTN3), statherin (STATH), cystatin D (CST5), BPI fold containing family A member 2 (BPIFA2), proline rich protein Hae Ⅲ subfamily 2 (PRH2), keratin 35(KRT35), histatin 1 (HTN1), amylase alpha 1B (AMY1B)] were 0.873, 0.100 and 0.023, respectively, and the total weight of the three was 0.996. The PCA diagnostic model of OSCC was further constructed by combining the eigenvectors of the above three components. The ROC curves of the training set and test set showed that the AUC values of the PCA model were 0.852 and 0.844, respectively, which were higher than those of other single genes. Conclusion The OSCC diagnostic model based on the expression levels of SMR3B, PRR27, HTN3, STATH, CST5, BPIFA2, PRH2, KRT35, HTN1 and AMY1B constructed with the PCA method and DEGs has a high diagnostic advantage. This study provides a theoretical basis for the early genetic diagnosis of OSCC and the application of the PCA model in clinical diagnosis.

Objective To investigate the clinicopathological characteristics, imaging manifestations, genetic manifestations, diagnosis and treatment of juvenile hyaline fibromatosis. Methods A case of juvenile hyaline fibromatosis was reported, and the patient's clinical manifestations, imaging examinations, histopathological examinations, genetic changes and treatment were summarized and analyzed. Results Juvenile hyaloid fibromatosis is more common in infants and children. This patient had typical clinical and pathological manifestations, including posterior occipital masses, skin and subcutaneous nodules, gum hyperplasia, joint contractures, and joint osteolytic lesions. The histopathological lesions were characterized by the proliferation of spindle cells in the tissue accompanied by a large amount of amorphous transparent matrix. Genetic testing was performed to confirm an ANTXR2 gene mutation, consistent with the known genetic changes of juvenile hyaline fibromatosis. The 6-month follow-up of the patient showed that there was no obvious recurrence after resection of the gum and facial mass. In addition to surgery, the treatment of this disease requires multidisciplinary symptomatic treatment combined with rehabilitation and supportive treatment to achieve a better prognostic effect. Conclusion Juvenile hyaline fibromatosis is a rare nonneoplastic autosomal recessive genetic disease. Mutations in the ANTXR2 gene lead to disorders of collagen synthesis and metabolism in the tissues and further cause subcutaneous nodules, gingival hyperplasia, joint contractures and bone dissolution.

Objective To compare the efficacy of different methods in the removal of calcium hydroxide from root canals and to provide a reference for clinical treatment. Methods A total of 160 extracted single-rooted mandibular premolars were instrumented up to ProTaper Universal F4. The roots were split longitudinally, and standardized groove and depression models were prepared and filled with calcium hydroxide. The samples were randomly divided into 4 groups (n=40) according to different irrigation methods: syringe needle irrigation, passive ultrasonic irrigation, XP-endo finisher (XPF) irrigation, and M3-Max irrigation. Each group was then divided into 2 subgroups (n=20) according to the irrigation protocol: NaOCl and NaOCl+EDTA. Photos of grooves and depressions were taken under a microscope after irrigation, and the residual calcium hydroxide was scored to compare the removal effects of different irritation methods and solutions. Results In the groove and depression model, when sodium hypochlorite is used as the irrigation fluid, ultrasound irrigation, XPF and M3-Max are better than syringe needle irrigation in removing calcium hydroxide (P < 0.05); when sodium hypochlorite combined with EDTA flushing, the effect of removing calcium hydroxide with ultrasound irrigation, XPF and M3-Max is better than that of syringe needle irrigation (P < 0.05); but there is no statistically significant difference between ultrasound, XPF and M3-Max (P > 0.05); when compared with the use of sodium hypochlorite, the combined use of EDTA irrigation could enhance the effect of ultrasonic irrigation, XPF and M3 Max on the removal of calcium hydroxide (P < 0.05), but there was no significant improvement in the syringe needle irrigation group (P > 0.05). Conclusion Sodium hypochlorite combined with EDTA can enhance the effect of ultrasonic irrigation, XPF and M3 Max on the removal of calcium hydroxide, and there is no significant difference among these approaches, which are more effective than syringe needle irrigation.

Vital pulp therapy aims to maintain healthy pulp tissue as much as possible to improve the long-term survival of teeth. It has limited indications and uncertain curative effects. The pathological changes in inflamed pulp are the histological basis for the determination of treatment strategies and the treatment outcome; however, pulp sensitivity testing cannot reflect the actual histological status of the pulp. With the development of basic and clinical research on vital pulp therapy, the innovation of modern diagnostic and therapeutic technology and capping material, vital pulp therapy can be used as a treatment of teeth on which it was previously thought pulpectomy was necessary. Based on the evidence-based literature, this paper analyzes and summarizes the pathological changes of pulpitis and clinical research on the treatment of pulpitis. Vital pulp therapy can be a treatment for mature teeth with carious exposure and symptoms of irreversible pulpitis if comprehensive applications, including laser Doppler flowmetry, tissue oxygen monitoring, magnetic resonance imaging and microscopy, are used to determine the degree of pulp retention and if infection control and the use of biocompatible capping material are emphasized. In the future, it will be necessary to improve the success rate of vital pulp therapy for the treatment of pulpitis through research on the mechanism of pulp repair and regeneration, the precise diagnosis of pulpitis, and the development of pulp capping materials.

Root fracture is a kind of dental trauma involving dentin, cementum, pulp tissue, periodontal membrane ligament and even the surrounding alveolar bone. It occurs frequently between the ages of 10-20, mostly in the area of the maxillary anterior teeth with high aesthetic requirements. The treatment goal for root fracture in permanent teeth is to maintain the physiological and functional integrity of the tooth as much as possible and to reduce the incidence of complications. Clinicians usually classify the affected teeth according to the position of the root fracture, including the apical, mid-root, cervical-mid-root and cervical segments, since it determines the treatment plan and the prognosis of the affected teeth. CBCT examination can avoid misdiagnosis and missed diagnosis of root fracture to the greatest extent. The sequential treatment plan of root fracture after permanent anterior tooth trauma includes initial emergency treatment, pulp vitality monitoring and complication management during follow-up. Emergency treatment mainly includes local anesthesia and repositioning, if displaced, the coronal segment of the tooth as soon as possible. Then, after checking its position radiographically, adjustment occlusion and flexible splinting for 4 weeks (4 months for cervical root fracture). The process of root fracture repair includes many tissues and is affected by many clinical factors. Timely and standardized treatment and close follow-up according to the Dental Trauma Guideline guarantee a good prognosis of root fracture. The closer the root fracture line is to the apex, the higher the survival rate is. In addition to the location of the root fracture line, the prognosis is affected by many other clinical factors, such as the displacement of the coronal fragment of the root fracture, the pathological state of the dental pulp, patient age, developmental stage of the root, timely and good replacement of the root fracture, splinting method, and the presence of other dental trauma complications. Pulp vitality should be monitored regularly, and root canal therapy of the coronal segment should be carried out only when infection of the pulp is established. This article reviews the classification, diagnosis, emergency treatment, sequential follow-up treatment, and prognostic assessment of root fracture trauma to provide suggestions for clinicians to manage root fracture trauma in permanent teeth.