Peri-implantitis is one of the most common complications in dental implant treatment. Peri-implantitis is a crucial implication of implant failure, which is characterized by high morbidity and intractability. Thus, how to understand peri-implantitis correctly and deeply, and how to prevent its occurrence, are important problems that every dental implant surgeon has to face.

How to improve the effects of treatment on patients with oral squamous cell carcinoma (OSCC) has always been the focus of clinical and basic studies. The standardized diagnosis and treatment of malignant tumors aim to improve the effects of treatment, and individualized treatment based on standardized diagnosis and treatment may further improve these effects. On the basis of the existing guidelines for the diagnosis and treatment of patients with OSCC, this study explored the opportunities and challenges of standardized and individualized diagnosis and treatment of OSCC. These challenges and opportunities were related to the updates of clinical and pathological staging system, surgical margins, and neck dissection in patients with OSCC at early stage and preoperative induction therapy and postoperative adjuvant treatment in patients with advanced OSCC. This study also shared ideas on clinical studies of OSCC to optimize the existing treatment schemes, improve the treatment effects, and enhance the guidelines.

Anti-programmed cell death protein 1 (PD-1) monoclonal antibody is a landmark drug in the field of malignant tumor treatment, and its emergence has resulted in the use of immunotherapy in treating various types of malignancies. A large number of clinical studies abroad have shown that it has a more significant effect than traditional strategies in the treatment of advanced head and neck cancer, and it has a significantly lower incidence of adverse events than chemotherapy. Recently, the clinical application of anti-PD-1 monoclonal antibodies in China has changed the traditional treatment mode of head and neck malignant tumors. Immunotherapy has become the first-line treatment option for recurrent/metastatic head and neck cancer. Furthermore, the indications of PD-1 monoclonal antibodies have been continuously expanded through clinical trials, and their biomarkers have been explored and validated. The application of PD-1 monoclonal antibodies tend to be individualized and precise and potentially improves the treatment levels of advanced head and neck malignancies.

Objective This study aims to study the effect of the enhancer of zeste homolog 2 (EZH2) inhibitor GSK126 on the proliferation and apoptosis of human tongue squamous cell carcinoma cells in vitro and explore its related mechanisms in order to obtain insights into the clinical treatment of tongue squamous cell carcinoma. Methods Different concentrations of GSK126 were applied to CAL-27 cells of tongue squamous cell carcinoma, and the effects of drugs on cell proliferation were detected through methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and 5-ethynyl-2’-deoxyuridine (EdU) fluorescence staining. Hoechst33342 fluorescence staining and the JC-1 method were used in observing apoptosis. The expression levels of extracellular regulated protein kinases (ERK), phospho-extracellular regulated protein kinases (p-ERK), Bax, Bcl-2, and Cleaved caspase-9 in Cal-27 cells were detected through Western blot. Results GSK126 inhibited CAL-27 cell proliferation and promoted apoptosis. GSK126 down-regulated the expression of p-ERK and Bcl-2 and increased the expression of Bax and Cleaved caspase-9 (P<0.05). Conclusion GSK126 can inhibit the proliferation of CAL-27 cells in tongue squamous cell carcinoma and promote its apoptosis, and the related mechanism may be associated with the inhibition of the MEK/ERK signaling pathway and activation of the Bax/Bcl-2 pathway.

Objective To investigate whether hyperthermia, chemotherapy and thermo-chemotherapy could trigger the expression of damage-associated molecular patterns (DAMPs). Methods The optimal working concentration of pingyangmycin (PYM) was detected by CCK-8 assay, and temperatures of 39, 42, and 45 ℃ were applied to the oral squamous cell carcinoma CAL27, SCC-15, and Tca8113 cell lines. The effects of different treatments on the apoptosis, calreticulin (CRT) membrane expression and high-mobility group box 1 (HMGB1) secretion of the cells were detected by using Annexin V/propidium iodide (PI), flow cytometry and enzyme-linked immunosorbent assay (ELISA) assay. SPSS 20.0 software was used for statistical analysis. Results Both hyperthermia and chemotherapy could increase the membrane expression of CRT and the secretion of HMGB1, and furthermore, thermo-chemotherapy group showed significantly increased in apoptosis, CRT membrane expression rate and HMGB1 secretion compared with chemotherapy group, and the difference was statistically significant (P<0.05). Conclusion Hyperthermia, chemotherapy and thermo-chemotherapy could induce oral squamous cell carcinoma cells succumb to death, and at the same time, they can effectively induce the membrane expression of CRT, and promote the secretion of HMGB1. Moreover, thermo-chemotherapy is significantly better than that of chemotherapy alone in the induction of cell apoptosis and DAMPs expression.

Objective This study aimed to investigate the expression of HOX transcript antisense intergenic RNA (HOTAIR) in salivary adenoid cystic carcinoma (SACC) and explore its influence on prognosis. Methods A total of 86 cases of patients with SACC who underwent surgical resection treatment from March 2007 to March 2014 were selected. In the same period, 45 cases of normal salivary gland tissues were obtained. The expression of HOTAIR was detected via real-time fluorescent quantitative polymerase chain reaction. The patients were followed up after the surgery, and the follow-up deadline was March 31, 2019. The deaths and survival times of patients were recorded. Based on the quartile value of the relative expression level of HOTAIR in SACC patients, the patients were divided into low expression group and high expression group. Kaplan-Meier method and Log-Rank test were used to compare the survival time of the two groups. Taking the age, sex, tumor location, pathological type, tumor diameter, TNM stage, nerve invasion and lymph node metastasis as independent variables, Cox proportional hazards regression model was used to analyze the multiple factors affecting survival time. Results The relative expression of HOTAIR in SACC tissue was 2.48±0.22, which was higher than that in normal salivary gland tissue at 1.03±0.13, and the difference was statistically significant (t=39.812, P<0.001). No nerve invasion and lymph node metastasis were observed in these patients compared with those patients with TNM stages Ⅰ or Ⅱ, while the relative expression of HOTAIR in the tissues of patients with TNM stages Ⅲ or Ⅳ, nerve invasion, and lymph node metastasis increased (P<0.05). Kaplan-Meier survival analysis showed that the average survival time and cumulative survival rate in the low expression group were higher than those in the high expression group [(113.32±10.77) months vs. (59.75±6.50) months and 72.73% vs. 39.06%, respectively, P=0.004]. Cox proportional hazard regression analysis showed that nerve invasion, lymph node metastasis, and the high expression of HOTAIR were the independent risk factors for the prognosis of patients with SACC (HR=3.274, 2.971, and 2.911, respectively, P<0.05). Conclusion HOTAIR was highly expressed in patients with SACC tissues and associated with poor prognosis. It is a risk factor for prognosis, and it is expected to be a potential marker for the prognostic assessment of patients with SACC.

Objective To investigate the expression of glycoprotein 130 (gp130) and interleukin 12 receptor β2 (IL-12Rβ2) in two subunits of interleukin-35 receptor (IL-35R), singal transducer and activator of transcription (STAT) 1 and STAT4 in oral lichen planus (OLP) tissues, and to explore the role and significance of IL-35R in the formation and development of OLP lesions. Methods Totally 41 samples of OLP tissues (OLP group) and 15 samples of normal oral mucosa (control group) were collected. The expression levels of gp130, IL-12Rβ2, STAT1, STAT4 mRNA in the tissues were detected by real-time fluorescent quantitative polymerase chain reaction and the distribution and expression of protein gp130 and IL-12Rβ2 were detected by immunohistochemistry. The potential relationship between gp130 and IL-12Rβ2 and clinical features of OLP was analyzed. Results 1) The expression levels of gp130, IL-12Rβ2, STAT1 and STAT4 mRNA in the OLP group were significantly higher than those in the control group (P<0.05). 2) The positive expression rates of gp130 and IL-12Rβ2 protein in the OLP group were higher than those in the control group (P<0.05). The expression of gp130 and IL-12Rβ2 proteins in OLP tissues were positively correlated (r=0.984, P<0.001). 3) The expression rates of gp130 and IL-12Rβ2 protein in erosive OLP tissues were significantly higher than those in non-erosive ones (P<0.05). Conclusion The expression of IL-35R and STAT is up-regulated in OLP tissues, and the expression of IL-35R is related to the clinical classification of OLP, suggesting that IL-35R might play an important role in the formation and development of damage OLP lesions.

Objective To investigate the effect of bilateral sagittal split ramus osteotomy (BSSRO) on temporomandibular joint (TMJ) symptom and condylar position in patients with skeletal class Ⅲ malocclusion treated with orthodontic-orthognathic surgical treatment. Methods Twenty-four patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment were included in the study. Their cone-beam computed tomography scans and TMJ symptom were evaluated, and their Helkimo index before BSSRO, 1 month after BSSRO, and 12 months after BSSRO was recorded. The maximum diameter of the horizontal and coronal sections, short axis diameters, neck width, height, joint space widths at different angles (45°, 90°, and 135°) of the condylar joint, bilateral condylar spacing, and different condylar angles (horizontal angle, vertical angle, and stress angle) in three dimensions were measured. Then, the changes in TMJ symptom and bone structure at different periods were analyzed. Results The Helkimo index was anamnestic (Ai) or dysfunctional (Di) levels 0 or 1 before and after BSSRO, and no difference in Helkimo index was observed. The horizontal angle and joint space widths at 45° and 90° increased whereas the joint space width at 135° decreased at 1 month after BSSRO compared with before BSSRO (P<0.05). Except for the increase in condylar horizontal angle (P<0.05), no significant difference in other measurement items was noted (P>0.05) 12 month after BSSRO. Conclusion BSSRO would not have a remarkable effect on the TMJ symptom and condylar position of patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treat?ment procedure and whose Helkimo index ranked Ai0, Ai1, Di0, and Di1.

Objective The aim of this study is to treat calcified root canal and assess the accuracy of guided endodontics using laser melting templates. Methods Two cases with calcified anterior teeth were treated with laser melting templates. Cone beam computed tomography (CBCT) was used to scan the maxillary teeth of patients before surgery to establish the root canal system model. The maxillary impression of the patient was made and it was scanned by a 3D scanner. The CBCT scans were matched with surface scans of plaster model. Mimics 19.0 and 3-matic 11.0 software were used to design the virtual planning to access cavities. The templates were produced by laser melting 3D printing. Access cavity was prepared under the guidance of laser melting template. Then the deviations of planned and prepared cavities in three dimensions and angle were measured. Results The two teeth obtained satisfactory results. The first case had a angle deviation of 1.77°, a drilling base deviation of 0.403-0.497 mm, and a tip of 0.433-0.537 mm. The second case had a angle deviation of 3.26°, a drill base deviation of 0.18-0.347 mm, and a tip of 0.310-0.463 mm. Conclusion Laser melting template-guided endodontics is an effective technique for the treatment of calcified root canal and can be used as a new strategy for the treatment of calcified canal.

Objective To evaluate the efficacy of scaling and root planing (SRP) with a periodontal endoscope in the treatment of residual pockets in patients with periodontitis after initial periodontal therapy. Methods Patients with residual pockets [probing depth (PD)≥5 mm] were included and randomly assigned to the endoscope group (SRP with a periodontal endoscope) or SRP group (SRP alone). The PD, attachment loss (AL), and bleeding on probing (BOP) of residual pockets were recorded before treatment and at 3 and 6 months after treatment. Data were analyzed with SPSS 20.0 software. Results Compared with the baseline values, the percentage of PD≥5 mm sites, PD, AL, and BOP (+)% in the endoscope group and SRP group at 3 and 6 months after treatment decreased (P<0.05). Compared with the values at 3 months after treatment, the percentage of PD≥5 mm sites, PD, AL, and BOP (+)% at 3 and 6 months after treatment decreased in the endoscope group (P<0.05), whereas no statistical difference in these values was observed in the SRP group (P>0.05). Compared with those in the SRP group, the percentage of PD≥5 mm sites and PD at 3 and 6 months after treatment and AL and BOP (+)% at 6 months after treatment in the endos?cope group decreased (P<0.05). Conclusion SRP with a periodontal endoscope shows a better effect in improving the PD, AL, and BOP of residual pockets (PD≥5 mm) in patients with periodontitis after initial periodontal therapy and has advan?tages in improving the long-term curative effect of this therapy.

Objective To study the stress distribution under dynamic loading in the presence or absence of an abutment buffer layer by using three-dimensional finite element analysis. Methods A three-dimensional solid geometric model of an implant in a human mandible was established on the basis of CT scan data. A buffer-free abutment prosthesis and a buffer-abutment abutment prosthesis were installed above the implant. The buffer layer was made of high-density polyethylene. A vertical load of 200 N and a horizontal load of 100 N (45°) were concentrated on the centers of the implant restorations of the two groups. Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface were compared via three-dimensional finite element analysis. Results Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface on the abutment with a buffer layer were significantly lower than those on the abutment without a buffer layer. Conclusion The increase in the buffer layer of the abutment neck significantly reduced stress on the implant neck, abutment, central bolt neck, and bone interface.

Objective This study aims to evaluate the clinical effect of oral repair membrane and β-tricalcium phosphate (β-TCP) on the treatment of jaw cyst. Methods A retrospective analysis was performed on 81 cases of jaw cysts, and clinical data were collected for the comparison of traditional surgical curettage (group A, 27 cases), biofilm covering bone wounds after curettage (group B, 27 cases), and β-TCP filling combined with biofilm covering. Results No recurrence occurred in 81 patients, and no significant difference in preoperative CT value among the three groups (P<0.05). Follow-up CT reexamination 3, 6, and 12 months after operation showed significant differences among the three groups of CT values (P<0.05). Group C was better than Group B or Group A (P<0.05). Conclusion In traditional jaw cyst curettage, the application of biofilm exhibited good osteogenesis effect, and the combined application of β-TCP and biofilm exerted a better effect.

Objective To investigate the application of nasal clip in the one-stage repair of unilateral cleft lip nasal deformity. Methods Sixty patients with unilateral cleft lip nasal deformity underwent one-stage repair in the Department of Cleft Lip and Palate, West China Hospital of Stomatology, Sichuan University, from January 2017—June 2018. Sixty patients were divided into three groups, nasal clip group, the nasal module group, and the control group. All of the patients were returned to the clinic after the operation (6-12 months), and the nasal appearance was evaluated. Results The nasal shape development and aesthetic effect in the nasal clip group were significantly improved than that in the control group (P<0.05). Conclusion The nasal clip has a good effect on the improvement of nasal appearance after the one-stage repair of unilateral cleft lip nasal deformity. The nasal clip is easy to operate, and the patient compliance is good, which is worthy of clinical promotion.

Objective To investigate the mechanism underlying the regulation of the invasion and metastasis of oral squamous cell carcinoma (OSCC) by long-chain noncoding RNA (lncRNA) PCGEM1 through the transforming growth factor (TGF) β2/Smad2 signaling pathways. Methods A total of 60 OSCC cases were collected. Cancer tissues and normal tissues more than 2 cm away from cancer tissues were also collected. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-148a and lncRNA PCGEM1 in OSCC, adjacent normal tissues, oral mucosa epithelial cells, KB, BcaCD885, SCC-4, CAL27, and SCC-15. The relationship between the expression of lncRNA PCGEM1 and miR-148a and the clinicopathological information of patients was analyzed. The lncRNA PCGEM1-silenced cell line KB-siPCGEM1 and negative control (KB-NC) group were constructed, and KB was used as the blank control group. The effects of lncRNA PCGEM1 on the proliferation, invasion, and migration of KB cells were determined via MTT, Transwell, and scratch assays. The bioinformatics website starBase was used to predict the complementary binding microRNA (miRNA) of lncRNA PCGEM1. Furthermore, the genes that the miRNA could target and bind were predicted in accordance with the website www.microRNA.org. Western blotting analysis was used to detect the expression of TGF β2/Smad2 signaling pathway proteins. Results qRT-PCR results showed that the expression level of lncRNA PCGEM1 and miR-148a in OSCC tissues was higher than that in normal tissues (P<0.05). The expression of lncRNA PCGEM1 and miR-148a in the cancer tissues of patients with different TNM grades, lymph node metastasis, and tissue differentiation was statistically significant (P<0.05). Compared with those in the blank control group and the KB-NC group, OD_{492 nm} value was significantly decreased and cell mobility was significantly reduced in the KB-siPCGEM1 group (P<0.05). Bioinformatics predictions showed that lncRNA PCGEM1 could bind to miR-148a in a complementary manner and that miR-148a had a targeted binding site with TGF β2. qRT-PCR and Western blotting analysis results showed that the expression levels of miR-148a, TGF β2, and p-Smad2 in the KB-siPCGEM1 group were significantly lower than those in the blank control and KB-NC groups (P<0.05), and no statistically significant difference between the blank control group and the KB-NC group was observed (P>0.05). Conclusion LncRNA PCGEM1 is highly expressed in OSCC. The high expression of lncRNA PCGEM1 may enhance the TGF β2/Smad2 signaling pathway by upregulating miR-148a, thus promoting the development of OSCC.

Objective This study aims to investigate the expression of fibroblast growth factor receptor like 1 (FGFRL1) in oral squamous cell carcinoma (OSCC) and reveals its association with tumor cell proliferation and migration. Methods Western blot was performed to detect the expression of FGFRL1 protein in OSCC tissues, adjacent normal tissues, OSCC cell lines and normal epithelial cells. After knocking down of FGFRL1 in HN4 cells, CCK-8 and Ki67 assays were performed to detect cell proliferation, wounding healing assay and transwell were performed to detect cell-migration. Western blot was used to detect the expression of protein related to epithelial-mesenchymal transition (EMT). Results The expression of FGFRL1 in OSCC tissues was higher than that in adjacent nontumor tissues, respectively (t=2.820, P=0.047 8). Moreover, the expression of FGFRL1 in OSCC cells was higher than that in HOK cells. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that FGFRL1 expression of FGFRL1 RNA in HOK cells was lower than that in OSCC cells. HN4 cells transfected with FGFRL1 siRNA were included in the experimental group, whereas HN4 cells treated with NC siRNA were included in the control group. CCK-8 experiment showed no significant difference between the experimental and control groups with regard to proliferation ability at 48 h (P=0.478 1) and 72 h (P=0.334 2). Migration experiment showed that the wound healing areas in the experimental group after 12 h (P=0.022 8), 24 h (P=0.005 1), and 36 h (P=0.009 5）were smaller than that in the control group. Transwell invasion assay showed that the number of invaded cells in the experimental group after 16 h (P=0.008 7) and 24 h (P=0.008 6) were lower than that in the control group. Knocking-down FGFRL1 up-regulated the expression of E-cadherin and down-regulated the expression of N-cadherin and Vimentin in HN4 cells. Conclusion FGFRL1 expression in the OSCC tissues was significantly higher than that in the adjacent nontumor tissues. FGFRL1 expression in the OSCC cells was significantly higher than that in the HOK cells, and FGFRL1 had no effect on cell proliferation but promoted tumor cell migration and EMT.

The application of cold atmospheric plasma to titanium surface modification has recently become a research focus in the area of material modification. Previous studies found that cold atmospheric plasma can affect the colonization of bacteria and biological behaviors of osteoblasts by changing the surface characteristics of titanium in vitro. In vivo studies reveal that cold atmospheric plasma can promote the process of osseointegration of titanium implants. This review focuses on research on the effects of the surface modification of titanium implants with cold atmospheric plasma on osseointegration.

Low-intensity pulsed ultrasound (LIPUS) is a common physical therapy to accelerate the healing of bone fracture and treat delayed union of bone fracture. Vessels, nerves, and bone tissue are essential constituents of bone system. Recently, increasing evidence has been revealed that LIPUS can not only promote bone regeneration by directly regulating osteoblasts, osteoblasts, mesenchymal stem cells, but also have a positive impact on the repair of bone healing through vessels and nerves. Thus, we reviewed and summarized the latest published literature about the molecular mechanism for the effects of LIPUS on bone regeneration, which might offer a promising therapy for bone-related diseases.

Veillonella species, known as the early colonizer of oral biofilm, are prevalent in oral microbiota. Seven Veillonella species have been isolated from oral cavity. Their distribution varies not only with different people but also with different sites in the oral cavity. Oral Veillonella are associated with oral diseases. They contribute to the adhesion of Streptococcus mutans and consume the lactate generated by streptococci. Veillonella species play an important role in the occurrence and development of periodontal diseases by providing adhesion sites for Porphyromonas gingivalis and boosting immune responses. The production of lipopolysaccharide and H₂S is related to other oral diseases, such as pulpitis, periapical periodontitis, and halitosis. Several studies have been conducted on the relationship between Veillonella and oral diseases and the interaction between Veillonella and other pathological microorganisms, but limited knowledge is available at the molecular level. This article reviews the research progress in the relationship between Veillonella and oral infectious diseases, such as dental caries and periodontal diseases.

Epigenetics refers to a steady change in the level of gene expression caused by non-DNA sequence changes. Microbes can modulate host inflammation through epigenetic pathways to evade or expend immune responses. As an important part of human microbes, oral bacteria also have various epigenetic regulation mechanisms to affect host inflammatory responses. This article reviews the common pathways of epigenetic regulation in microbe infection and the regulation of host epigenetics by using oral microbes to provide a reference for the study of epigenetic-related mechanisms in oral diseases.

The bone morphogenetic protein (BMP) 1/tolloid (TLD) proteinase family is a group of important metalloproteinases, which play key roles in the growth and development of tissues and organs via regulating the biosynthetic processing of the extracellular matrix. Clinical reports have revealed that mutations in the genes encoding BMP1/TLD proteinases lead to dentinogenesis imperfecta type Ⅰ, accompanied with osteogenesis imperfecta. Therefore, this proteinase family is essential for the development of hard tissues. In this study, we review the research progress in the function and mechanism of the BMP1/TLD proteinase family in the development of teeth and bone.

Infantile myofibromatosis is a rare benign childhood myofibroblastoma. A case of infantile myofibromatosis of the left mandible was reported, and relevant literature was reviewed to discuss the clinical characteristics, pathogenesis, imaging characteristics, pathological characteristics, differential diagnosis, and the treatment of the tumor to improve the understanding of the tumor.

The use of orthodontic traction to preserve healthy subgingival residual root is a classical method combining the treatment of restoration and orthodontics. Based on the target restoration space (TRS), by establishing a TRS digital model, the final traction position of the subgingival residual root can be preset. After evaluating the key parameters such as crown-to-root ratio and minimum crown height, clinicians can estimate the treatment time and exclude cases with bad preset position. The time of traction treatment can be effectively reduced, and the efficiency and efficacy of the entire treatment can also be improved.