Since an epidemic occur of Corona Virus Disease 2019(COVID-19) in December, 2019, all the dental healthcare service providers in our country have been greatly impacted. The strategy of managing the dental clinics is quite different from that of the medical healthcare clinics, and the key point of the administration of those dental healthcare providers is to focus on the management of outpatient care because they only supply just a little bit of inpatient care service but quite an large amount of outpatient care service. So we think the next step is to make plausible and effective scenarios to protect our dental healthcare staff and patients against corona virus infection during the treatments procedures after the reopening all of our dental clinics. To overcome this harsh condition, the infection prevention and control strategies adopted by the Stomatological Hospital, Southern Medical University were designed to be flexible and could be adjusted promptly according to the national and local governmental orders and latest guidelines released by the Centers for Disease Control and Prevention. All these prevention procedures and protocols were customized to fit our own situation and have been updated for several times based on the latest global pandemic reports. After going through the hardest time in the past four months, it’s considered that our COVID-19 prevention rules have been proved to be efficient and work well. Further more, it has made massive progress for the hospital in improving the capability of dealing with this state of emergency, especially by previewing and triaging patients strictly to cut off the possible coronavirus spreading from the original step, enhancing the standard precautions and those specific protocols made for minimizing the droplets, aerosol and contact transmission of COVID-19 indoors. Besides, a daily supervision system was set up as a routine job and a team of qualified infection prevention specialists were assigned to check and report every incorrect details during the whole procedure of dental practice. Meanwhile, the safety and well-being of the public and our medical workers could be also guaranteed through following those detailed prevention scenarios.
A substantial revision of the classification of ameloblastoma was made by the World Health Organization (WHO) in the fourth edition of the Classification of Head and Neck Tumors in 2017, which was based on the review and summary of much clinical research data and prospective evaluation of the latest results of genetic research. The new classification is simpler and more practical. It retains two subtypes, the unicystic type and extraosseous/peripheral type, classifies the remaining types as ameloblastoma (classic), defines metastatic ameloblastoma as a benign tumor and simplifies the classification of ameloblastic carcinoma, which has important guiding significance for clinical diagnosis and treatment. Moreover, the new classification included the latest advances in the genetic research on ameloblastoma, demonstrating that the BRAF gene mutation was found in approximately 60% of ameloblastoma cases. The classification provides a new concept and direction for studying the pathogenesis of ameloblastoma, and BRAF-targeted therapy may be an emerging therapy for some ameloblastoma patients with multiple recurrence or surgical contraindications. This article analyzes the intrinsic logic of these changes via a review of the relevant literature and combination of clinical experiences to better understand the new classification. In 2017, the WHO′s new classification of ameloblastoma summarized the experience and achievements in histopathology and clinical treatment of ameloblastoma in the prior 10 years, indicating that BRAF-targeted treatment may bring new treatment options and hope for patients with recurrent or inoperable ameloblastoma.
Objective To investigate the effects of casein kinase 2 interacting protein-1 (CKIP-1) on the osteogenic differentiation ability of human periodontal ligament stem cells (hPDLSCs). Methods The hPDLSCs were obtained by primary culture with periodontal ligament tissues that were collected from normal humans. Then, a lentiviral vector containing a CKIP-1-specific siRNA sequence was constructed, and the transcriptional level of CKIP-1 in hPDLSCs was downregulated after vector infection. The P4 cells were divided into four groups: the control group, negative control group (infected with a control vector), CKIP-siRNA group (infected by a CKIP-1 siRNA lentivirus) and CKIP-1 group (infected by a CKIP-1 overexpression virus). All of the cells were cultured under osteogenic induction for 21 days. Then, alizarin red staining and quantitative determination were performed to detect the osteogenic differentiation ability of the hPDLSCs. In addition, qPCR was used to detect the transcriptional level of osteogenesis-related regulatory factors, such as Runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteocalcin (OCN), and receptor activator of nuclear factor kappa-B ligand (RANKL), and the osteogenesis-related regulatory factors of the bone morphogenetic protein (BMP) signaling pathway. Results There were no differences in the indexes between the negative control group and the control group (P > 0.05). Compared with the negative control group, the CKIP-siRNA group demonstrated more mineralized nodules (P < 0.05), significantly increased calcium salt deposition (P < 0.05), and increased mRNA levels of osteogenesis-related regulatory factors, such as Runx2 , ALP, OCN, and RANKL, and the osteogenesis-related regulatory factors of BMP signaling pathway (P < 0.05). Conclusion Downregulation of CKIP-1 could promote the osteogenic differentiation of hPDLSCs, which is related to the transcription level of osteogenic-related regulatory factors.
Objective To explore the inhibitory effect of celecoxib (CELE) on the proliferation of tongue squamous cell carcinoma Cal-27 cells and its mechanism. Methods A CCK-8 assay was used to investigate the cytotoxicity of different concentrations CELE(10, 20, 40, 60, 80, and 100 mol/L) at 24 and 48 h in Cal-27 cells. According to the concentration of CELE, samples were divided into a control group (0 μmol/L) and experimental groups (10, 20, and 40 μmol/L), and cell invasiveness was detected by the Transwell method. The expression levels of c-Myc and Cyclin D1 mRNA were detected with qPCR, and western blots were used to detect the expression of phosphate and tension homologue deleted on chromosome ten (PTEN), phospho-protein kinase B (p-AKT) (Thr308), c-Myc, cyclin D1 and other proteins in Cal-27 cells after 24 h of treatment with different doses of CELE (10, 20, and 40 μ mol/L) and after 6, 12, and 24 h of treatment with 40 μmol/L CELE. Results The different concentrations of CELE were able to inhibit the proliferation of Cal-27 cells, and the higher the concentration of CELE was, the more significant the inhibition of the proliferation of Cal-27 cells was. The cell survival rates of cells exposed to 40 μmol/L CELE were 80% and 75% after 24 and 48 h, respectively. In the four groups of patients, the number of invasive cells was compared, and the results in decreasing order were the control group, 10 μmol/L CELE, 20 μmol/L CELE, and 40 μmol/L CELE. The expression level of c-Myc, cyclin D1 mRNA and the protein in P-AKT (Thr308), c-Myc, and cyclin D1 significantly decreased and the expression of PTEN protein increased in the Cal-27 cells after administration of CELE at different concentrations. Conclusion CELE can inhibit the proliferation of Cal-27 cells, possibly through inhibition of the expression of proliferation signal factors, such as c-Myc and cyclin D1, by activating the PTEN signaling pathway.
Objective The short-term clinical effects of two kinds of normal temperature flow root sealers (the calcium silicate-based sealer iRoot SP and the siloxane-based sealer GuttaFlow2) combined with single point filling technology and a frequently-used sealing agent (AH Plus) combined with continuous wave hot tooth filling technology were evaluated. Methods A total of 279 teeth (656 root canals) were randomly divided into three groups: the iRoot SP group, GuttaFlow2 group and AH plus group. We recorded the filling time of each root canal, collected a digital dental film to evaluate the filling effect of each root canal, and conducted a follow-up visit one week and one month after the operation to record the incidence of pain. We used SPSS 18.0 to analyze the above data. Results There was no significant difference in the root canal filling effect among the three groups (P > 0.05). There was no significant difference in the filling time between the iRoot SP group and the GuttaFlow2 group (P > 0.05), but the filling time was significantly shorter in the AH Plus group (P < 0.05). There was no significant difference in the postoperative pain between the iRoot SP group and the GuttaFlow2 group (P > 0.05), and the incidence of pain in the iRoot SP group and the GuttaFlow2 group was lower than that in the AH Plus group (P < 0.05). Conclusions GuttaFlow2 and iRoot SP combined with single point filling technology can save filling time and obtain good clinical effects compared with frequently-used hot tooth filling technology and the incidence of postoperative pain was low.
Objective To evaluate the clinical effects of full-arch cement-retained implant-supported combined crowns and screw-retained implant-supported bridge dentures in complete or half edentulous patients. Methods A total of 25 patients with complete or partial edentulous dentures followed up for 1, 3, and 5 years in our hospital from June 2013 to June 2018 and were treated with Straumann bone horizontal implantation, cobalt-chromium stenting and cobalt-chromium porcelain restoration with cement-retained and screw-retained implant-supported fixed dental prostheses to evaluate the accumulative implant survival rate, accumulative prosthesis survival rate, mechanical complications, and biological complications in both groups. Results There were 25 complete or half edentulous patients who received 165 Straumann implants and 28 implant-supported fixed dental prostheses in this study. There were 11 cases with 69 implants in the cement group and 17 cases with 96 implants in the screw group. The accumulative implant survival rate was 100% in the cement group and 96.9% in the screw group. The accumulative prosthesis survival rate was 100% in both groups. The cumulative peri-implant mucositis rate was 23.2% in the cement group and 29.2% in the screw group, and the peri-implantitis rate was 6.8% in the cement group and 7.3% in the screw group. There was 1 case of porcelain collapse (n=1/11) and no screw of abutment loosening in the cement group and 4 cases of porcelain collapse (n=4/17) and 1 case of screw loosening in the screw group. No fracture of abutment was observed in either group. There was no difference in bone loss between the two groups in the first year (P > 0.05), and a higher rate of bone loss was found in the screw group in the third and fifth years (P < 0.05). There was no difference in the sulcus bleeding index(mSBI) between the two groups in the first year and the third year (P > 0.05) and a higher modified mSBI value in the cement group in the fifth year (P < 0.05). Conclusion The survival rates of the implant and prosthesis for cement-retained or screw-retained implant-supported fixed dental prostheses were both high, but there were more mechanical and biological complications in the traditional cobalt-chromium alloy screw-retainer group. The removal of residual adhesives must be reasonably considered when choosing the cement retention method.
Objective To investigate the application of digital immediate implant and angle screw channel abutment in the aesthetic area and the related influencing factors by reviewing the data of one case of immediate implant repair of the upper anterior teeth and related literature. Methods One case of refractory chronic apicitis of the upper anterior teeth involved immediate implantation after extraction. The digital information of the patient was obtained by CBCT and intraoral scanning. According to the information from the patients, a preoperative evaluation was performed; a treatment scheme was formulated; a minimally invasive extraction was performed; implants were placed under a digital guide plate; and temporary restoration was immediately performed. Six months after the operation, the patients underwent individualized mold removal, and angle screw channel fixation was completed. We observed the cosmetic effects and soft and hard tissue and gingival contour maintenance effects after restoration and reexamined the patients 6 months after restoration. In addition, the relevant literature was reviewed. Results The height of the gingival margin and gingival papilla and gingival contour of this patient were well maintained. The red and white aesthetic effect was good. There was no redness or swelling of the gingiva nor obvious changes in the soft and hard tissues around the implant 6 months after restoration, and the patient was satisfied. The results in the literature review show that a preoperative design based on CBCT and intraoral scanning data combined with digital software and a whole digital guide plate make the procedure more accurate and safer. These factors can not only avoid important anatomical structures and serious surgical complications but can also result in implantation in the best three-dimensional position. In addition, the application of digital impression technology and CAD/CAM increases the efficiency, speed, accuracy, simplicity, and comfort of oral impressions and the construction of temporary and final prostheses more precise and faster, greatly improving clinical efficiency. Conclusion Digital immediate implant and angle screw channel abutment is a good method to restore the aesthetics and function of missing teeth and to avoid the complications caused by adhesive residue.
Objective To investigate the etiology, diagnosis and treatment of granulomatous cheilitis（GC）. Methods For a patient with recurrent granulomatous cheilitis for more than 1 year in whom no medical treatment was used, only systemic treatment of the teeth was performed, and its efficacy was observed. We also reviewed the relevant literature. Results The vermilion of the right lower lip of the patient was obviously swollen and soft. There was rebound and no pitting edema with palpation. A large dark red rash with local desquamation was observed on the skin over the right mandible. There were residual roots in tooth 35, 46, and 47, a porcelain bridge on 11-24, deep caries in 15, 16, 26, and 36, and many calculi in the whole mouth, and the gingival margin was obviously congested and swollen. Histopathological examination showed many lymphocytes infiltrated the superficial dermis, and granulation tissue, plasma cells and eosinophils infiltrated locally. The diagnosis was as follows: ① GC; ② 35, 46, and 47 residual roots; ③ 15, 16, 26, and 36 deep caries; ④ gingivitis. The treatment included extraction of 35, 46, and 47 residual roots, periodontal basic treatment, and fillings for 15, 16, 26, and 36. No drugs were administered except for 3 days after tooth extraction. After 5 weeks of treatment, the swelling of the lower lip and the skin rash completely disappeared. There was no recurrence in the follow-up observation at six months. Through a literature review and analysis, we found that GC may be related to various factors such as immunity, infection, and genetics. Local oral infections may be closely related to the incidence of GC. Conclusion Resolution of local oral infections is effective for the treatment of granulomatous cheilitis, and local oral infections may be closely related to the onset of granulomatous cheilitis. In the treatment of granulomatous cheilitis, attention should be paid to the systematic examination of the oral condition, and the treatment of suspected lesions in the oral cavity should begin in the early stages of treatment.
Patients seeking implantation often have several systemic diseases, which will introduce complications to treatment. This paper reviews the risk assessments and prevention of systemic diseases in patients with oral implant therapy with the relevant literature. The patients with cardiovascular diseases are prone to stroke and cardiac arrest, and anticoagulants and antihypertensive drugs will complicate cases. The potential risks of endocrine system diseases are infections and crises caused by unstable hormone levels. The risks of respiratory diseases are dyspnea and swallowing devices. The difficulty of treating patients with neuropsychiatric diseases is attributable to poor cooperation and adverse effects of the drugs. Bone and joint system diseases may decrease the success of implantation. Hematological system, digestive system and kidney diseases may lead to hemorrhage. By inquiring about detailed medical and medication history, evaluating vital signs and detecting important objective indicators, performing targeted measures, discussing with specialists, and observing patients closely, clinicians can avoid the abovementioned risks.
At present, conventional periodontal treatment cannot achieve complete and effective periodontal tissue regeneration. Cell sheet technology (CST) is a kind of cell transplantation method without scaffold material that can maintain complete extracellular matrix, important ion channels of cells, growth factor receptors, etc., and ensure the interaction between cells and the extracellular matrix. In this paper, the application and research progress of the cell sheet in the field of periodontal tissue regeneration are reviewed. Different types of seed cells can be prepared into monolayer cell sheet, multilayer cell sheet, cell sheet fragments and cell sheet polymers. Among them, the monalayer cell sheet is easily damaged and requires high deoperator; the multilayer cell sheet shows improved mechanical properties, but its thickness needs to be controlled to avoid cell necrosis. The cell sheet fragment can be used in the narrow space between the alveolar bone and root cementum to reduce the difficulty of operation and improve the mechanical properties of the cell sheet. Cell sheet polymers are three-dimensional structures that can provide strong mechanical support and improve the stability of the cell sheet, but the stability of their biological activity needs to be further improved. In methods for construction of the cell sheet, the antifibrosis and antiangiogenesis properties of the amniotic sheet have shown that this structure is suitable as the matrix of cell culture; the method of using a temperature-sensitive culture dish is simple and easy; continuous induction with vitamin C can retain some important proteins on the cell surface; and the magnetic tissue engineering method can increase cell adhesion and easily form a stable cell sheet. The above methods have their own characteristics. In clinical applications, monolayer cell sheet is mainly used for direct transplantation to the receiving site to construct periodontal tissue; multilayer cell sheet of the same or different species overlap and are then transplanted to the receiving site; and multilayer cell sheet of the same kind are wrapped with scaffold material and then transplanted to the receiving site to construct a three-dimensional structure. Overall, cell sheet technology has shown good potential in periodontal tissue regeneration.
Since the digital impression technique has already been widely used in dental therapy, it has grown into a popular option among implant practitioners. The advantages of the digital impression technique are as follows: better experience for patients during the treatment; less chair-side time consumption; and reliability in making the precise impression. Thus, we reviewed the relevant factors that impact the precision of the digital impression technique and introduced its influence mechanism through an evidence-based method that was based on analyzing in vitro and in vivo literature published within the previous 5 years, with a focus on such considerations as relevant factors to dentists, digital impression systems, patients, and the environment. A review of the literature showed that the main factors that have a large influence on impression precision are imaging techniques and the software for the impression system. However, due to the development of impression systems that are restricted at scientific and technological levels, impression precision is affected by multiple factors, such as scanning techniques, dentist operation proficiency, material and contours of scanbodies, patient conditions, and ambient light. Dentists are advised to scientifically choose the impression system, limit ambient light and adopt direct techniques that could enhance impression precision. In the future, the development of impression systems could reduce the systematic errors, decrease the operating complexity of dentists, and improve impression precision.
Epigallocatechin-3-gallate (EGCG) has antibacterial, anti-inflammatory, antitumor, and other functions. EGCG and its anticancer mechanism are hot research topics in the prevention and treatment of oral cancer. In this paper, the prevention and treatment effects of EGCG on oral cancer and its anticancer mechanism are reviewed. The results show that EGCG can regulate multiple cell metabolic signaling pathways, such as the G protein coupled receptor signaling pathway, mitogen-activated protein kinase (MAPK), and the Wnt signaling pathway, and it can regulate DNA methylation and act on RNA of oral cancer cells directly or indirectly through the oral cancer cell signal transduction network to inhibit the development of oral precancerous lesions and oral cancer. EGCG combined with 5-fluorouracil can enhance the curative effect and reduce adverse effects and is expected to be a new drug for the prevention and treatment of oral cancer.
The loss of jaw position relationship will seriously affect the face and masticatory function of patients, and accurate restoration of vertical dimension of occlusion (OVD) is the key to occlusal reconstruction in edentulous patients. There are many methods to measure OVD in edentulous patients. In this paper, the working principle, scope of application, advantages and disadvantages, measurement methods and operation points of OVD recording method are reviewed in order to provide some reference for clinical treatment. The results show that the pre- extraction recording method is more objective and accurate, but the diagnosis model before extraction is required to accurately reflect the patients′ original OVD; the rest and stop jaw reference method is easily affected by subjective factors, and the edentulous patients with unstable jaw relationship are forbidden; the swallowing method is more subjective, especially suitable for patients with emotional tension and poor coordination; The facial landmark measurement method is more objective, but it is also affected by some subjective measurement factors. The patients with maxillofacial malformation are forbidden; the subjectivity of speech method is strong, and the accuracy of measurement results is closely related to the clinical experience of doctors, and the patients with aphasia and deafness are forbidden. X-ray cephalometric method and finger measurement method have strong objectivity. They are new measurement methods in recent years and have a bright future. Among them, finger measurement method is especially suitable for patients with maxillofacial deformity or postoperative deformity of tumor.