Nowadays, with the innovation of surgical technology and the development of bone substitute materials, scholars at home and abroad have proposed a variety of horizontal bone augmentation techniques to reconstruct the contour of alveolar ridge and provide reliable guarantee for the initial stability of implants. However, the success of these techniques will also be affected by some factors. This paper discusses the technical points of horizontal bone augmentation, compares and analyzes the clinical efficacy of tent screw technology and conventional GBR technology in horizontal bone increment through two cases, so as to provide reference for clinicians to choose the method of horizontal bone augmentation for severe alveolar ridge atrophy.

The best way to repair edentulous patients has always been a controversial topic. With the continuous development of implant technology, the challenge for edentulous reconstruction is how to reduce the difficulty and cost of surgery while ensuring the quality of repair. "All-on-Four" technology is currently a hot spot in clinical research. It can maximize the use of residual alveolar bone to achieve immediate loading and avoid complex bone grafting, which is widely popular among clinicians and highly accepted by patients. However, "All-on-Four" technology also faces many challenges. Indications of surgical treatment, surgical procedures, prosthetic plans and prosthetic complications are still to be discussed. This article will discuss, summarize and reflect on the advantages and disadvantages of "All-on-Four" implant technology to help clinicians use it reasonably.

Objective To observe the esthetic effect and soft tissue stability of the final restoration by using the temporary crown to shape the soft tissue around the implant in the anterior maxilla. Methods In this study, 21 cases of upper anterior maxilla which needed to be implanted were selected. Temporary crowns were carried out immediately or delayed after dental implant. Soft tissues around the implants were shaped. After soft tissues were stabilized, they were duplicated by the custom impression coping technique and the final restorations were completed. The pink esthetic score (PES) was used to evaluate the esthetic effect of soft tissues around the implants. Results Eleven patients with PES≥12, 9 patients with 8≤PES≤11, obtained better esthetic effect. The implant in anterior maxilla in one case supported fixed bridge reparation. Due to the horizontal absorption of alveolar bone, the soft tissues receded. So in the later stage, esthetic treatment was carried out through Gingival Porcelain. Twenty-one patients were observed for one year after final restoration. Then PES was again used to evaluate. The results showed that all the cases obtained good aesthetic effect. Conclusion After anterior teeth implantation, the soft tissues can be shaped by temporary crowns, which can adjust the soft tissues to a better appearance and a stable shape. This method is necessary to implant in the anterior maxilla and is worth popularizing in clinical practice.

Objective　 To evaluate the effect of a silane coupling agent (γ-MPS) on the formation of 10-MDP-Ca salts. Methods　 The experimental primer was obtained by adding different weight (0%、5%、10%、15%) of γ-MPS in 10% 10-MDP solution. Silane solutions of different weight (5%、10%、15%) are also prepared. The primer reacted with hydroxyapatite (HAp) to obtain residual recants. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis（XRD） was performed to evaluate the formation of 10-MDP-Ca salts. Results　 Fourier transform infrared spectroscopy showed that the peak of methacryloxy carbonyl group of 10-MDP was detected in the residual recants after treatment with primer containing 10-MDP. After treatment with different weight of γ-MPS, there was no difference when comparing with the control group. X-ray diffraction results indicated that the residual recants were significantly different from that of the 10% 10-MDP group when 10% or 15%γ-MPS were added. Conclusions　10- MDP and HAp can form 10-MDP-Ca salts, while γ-MPS cannot react with HAp. 10% or 15% γ-MPS inhibited the formation of 10-MDP-Ca salts.

Abstract：　Objective　To explore the potential mechanism of main active components Tripterygium wilfordii in the treatment of recurrent aphthous ulcer (RAU) based on network pharmacology. Methods The components of Tripterygium wilfordii were searched through the TCMSP and TCMID databases. The related targets of RAU were obtained through Gene Cards, OMIM, et al. The RAU targets was mapped to the targets of Tripterygium wilfordii to screen out the common targets as the treatment of RAU targets of Tripterygium wilfordii. Using Cytoscape software to construct a component-target regulatory network and protein-protein interaction network, use the DAVID database to analyze the GO classification enrichment analysis and KEGG signal path analysis. Results 51 components and 150 the treatment of RAU targets of Tripterygium wilfordii were obtained. The key active ingredients include triptolide, kaempferol, nobiletin et al. The key targets include AKT1, TNF, VEGFA et al. KEGG signaling pathway analysis of the treatment of RAU targets of Tripterygium wilfordii obtained 117 signaling pathways, mainly related to TNF signaling pathway and VEGF signaling pathway, T cell receptor signaling pathway etc. GO classification enrichment analysis obtained 80 GO term, mainly involved in response to drug, enzyme binding and membrane raft, etc. Conclusions Based on network pharmacology, this study preliminarily revealed the pharmacological basis and mechanism of action of active components of Tripterygium wilfordii in the treatment of RAU. It can provide a theoretical basis for the subsequent treatment of RAU drugs from Tripterygium wilfordii with no toxic side effects.

Abstract：　Objective　To compare the 3D printed zirconia implants and computer aided design-computer assomated manufacture (CAD/CAM) zirconia implants and pure titanium implants in the differences in osseointegration in animals, and evaluated the osteointegration performance of zirconia implants for zirconia implantation in bones. Methods　Six Beagle dogs were selected, and randomly planted 3D printed zirconia implants, CAD/CAM implants and titanium implants in tibias, 20 for each material. Success rate and osteointegration performance of zirconia implants were evaluated 8 weeks later. Osseointegration performance was compared with titanium implants. The observational indicators of this study were success rate of the bone implant, reverse torque test, bone-to-implant contact rate, and bone density around the implants. SPSS17.0 software package was used for statistical analysis of the data. Results　The success rates of the three groups of bone implants were all 100%.The reverse torque values of CAD / CAM zirconia implant group were all greater than 35 N; the reverse torque values of zirconia implant group by 3D printed technology were all greater than 35 N; the reverse torque value of 2 implants in the titanium implant group was between 20 and 35 N, and the reverse torque value of 8 implants was greater than 35 N. Histological observation findings: The rates of bone osseointegration without marrow cavity of 3D printed zirconia implants, CAD/CAM zirconia implants and pure titanium implants exhibited （66.35±6.64%）、（61.32±10.41%）and（58.88±25.10%）, respectively. The rates of bone osseointegration with marrow cavity of 3D printed zirconia implants, CAD/CAM zirconia implants and pure titanium implants displayed （49.57±5.04%）、（42.21±18.58%）and（38.45±23.27%）, respectively. And the average rate of bone osseointegration of 3D printed zirconia implants, CAD/CAM zirconia implants and pure titanium implants revealed （58.94±6.31%）、（53.56±8.77%） and（48.31±20.76%）, respectively. Moreover, the bone density around 3D printed zirconia implants, CAD/CAM zirconia implants and pure titanium implants demonstrated (60.59±7.31%), (58.50±6.36%) and (58.18±14.80%), respectively. There was no significant difference after data analysis (P> 0.05). Conclusions　Zirconia implants have the similar osseointegration ability as pure titanium implants, and can form close direct bone contact. Therefore, zirconia implants may be an optional material for dental implants.

Objective To analyze the clinical characteristics, treatment，prognosis and prevention of oroantral communications (OACs) caused by tooth extraction. Methods From January 2017 to June 2020, 106 cases with OACs treated in the Stomatological Hospital of the Fourth Military Medical University were collected and analyzed retrospectively. Results The majority of OACs were found in 10 to 30 years old patients, and the ratio of male to female was 1:1.25. The predilection site of OACs was the maxillary third molars. The main cause of OAC was the extraction of maxillary impacted tooth. All patients were treated by placing a collagen plug in the alveolar to close the communications, and no oroantral fistula occurred. Conclusions OACs can occur in all age groups and is more common in young people. Anatomical factors, periradicular bone destruction, and operator’s experience are three main risk factors for OACs. These factors should be fully considered before operation to prevent OACs. Conservative treatment of OAC with collagen plug can effectively prevent oroantral fistula.

Objective To explore the effect of the initial biological width of implant on marginal bone level (MBL). Methods 80 patients who received Straumann bone level implant and fixed prosthesis in the posterior dental area were selected. The oral panoramic radiographs of each implant at four time points (preoperative, postoperative, second-stage, follow-up) were measured. The soft and hard tissue space implanted immediately after operation above the shoulder level was defined as initial biological width (IBW), The IBW value was the initial mucosal thickness during equicrestal implantation, or the sum of mucosal thickness and implant depth during subcrestal implantation. IBW was grouped by 3.5 mm to compare MBL of follow-up implant. Results After 1–5 years of follow-up, 127 implants with 254 sites were included. IBW≥3.5 mm group demonstrated better MBL (0.40 mm vs. 0.00 mm, P＜0.05). With IBW≥3.5 mm, the marginal bone level of the implant was more likely to stabilize at or above the shoulder level (95.6% vs. 87.2%, P＜0.05). Conclusion Both mucosal thickness and implant depth affect implant MBL. For Straumann bone level system, with IBW≥3.5 mm, MBL is more likely to stabilize at or above the shoulder level.

Objective To analyze the labial bone dehiscence, fenestration and root resorption of upper incisors in adult skeletal Class II Division 1 patients with different periodontal phenotypes. Methods 24 cases of skeletal Class II Division 1 adult patients were included in the study. Gingival thickness of upper incisor was measured quantitatively and noninvasively by overlapping CBCT and digital model data before orthodontic treatment. According to the gingival thickness of the upper incisors, patients were divided into thin PP group (gingival thickness < 1.5mm) and thick PP group (gingival thickness ≥ 1.5mm). CBCT was used to measure the occurrence and progress of fenestration, dehiscence and root resorption before and after treatment. Results The incidence of dehiscence and fenestration on upper incisor of all included patients was 31.2% and 18.8% respectively before treatment and increased to 75% and 20.8% after treatment. The distance between the crest of labial alveolar ridge to the cemento-enamal junction (LA-CEJ) was 3.19 ± 0.43mm in the thin PP group, which was significantly higher than that in the thick PP group (2.16 ± 0.11mm), but there was no significant correlation between LA-CEJ and gingival thickness (r = -0.1108, P = 0.6146). There was a positive correlation between root resorption and gingival thickness (r = 0.4223, P = 0.0447). The root resorption in the thick PP group (2.24 ± 1.24mm) was significantly higher than that in the thin PP group (1.08 ± 0.73mm). Conclusions The labial alveolar bone dehiscence, fenestration and root resorption of upper incisors were aggravated after tooth extraction orthodontic treatment. The risk of vertical alveolar bone resorption is increased in the thin PP group, and the risk of bone fenestration and root resorption is increased in the thick PP group.

Objective To analyze the effect of stabilization splint on condylar bone remodeling in patients with temporomandibular disorders (TMD) from the aspect of condylar bone mineral density (BMD) changes. Methods 40 TMD patients treated with stabilization splint were selected. Cone beam computed tomography (CBCT) scanning was taken before and after treatment. The condylar BMD was measured by the Density function of MIMICS 21.0 software, and the condylar BMD of the anterior slope, the top and the posterior slope was analyzed statistically. Results Before and after treatment, the condylar BMD in female was significantly higher than that in male (P＜0.05). The condylar BMD in 22–40 age group was significantly higher than that in 13–21 age group (P＜0.05). Compared with pre-treatment, the condylar BMD increased significantly after treatment (P＜0.05). The condylar BMD of the anterior slope was (347.31±11.98) HU before treatment and (367.69±12.98) HU after treatment; that of the top was (310.46±12.40) HU and (331.20±13.56) HU; the posterior slope was (291.55±13.75) HU and (319.94±14.19) HU respectively. There was no statistical difference of the increment between gender and age. Conclusion There are differences in condylar BMD between gender and age. Stabilization splint is beneficial to TMD patients for a better condylar remodeling.

Dental implant has become the preferred treatment method for many patients due to its huge advantages in solving edentulou defects. How to promote the osseointegration of the implant-bone tissue interface is the key to the success of implant in clinic. Therefore, surface modification of implant has always been the hot topic of research. Bone tissue contains a large number of trace elements such as calcium, phosphorus, zinc, magnesium, and strontium, which are essential for the growth and development of bone tissue. Therefore, it is possible to promote implant osseointegration by incorporating trace elements into the implant surface. This article focuses on the related technology of implant surface modification and the specific mechanism of trace elements to promote osseointegration.

Abstract: The ideal goal of tissue engineering is to maintain, improve, repair damaged tissues and organs with growth factors, stem cells and scaffold. Neuregulin-1 (NRG-1) belongs to an endogenous growth factor which exerts roles through its receptor tyrosine kinases (ErbB). Current studies have shown that combining NRG-1 with ErbB in nerve and cardiovascular systems can activate a series of signaling pathways to promote cell proliferation, migration, anti-apoptosis and directional differentiation of induced pluripotent stem cells, which is conducive to regeneration of nerve and cardiovascular tissues. Therefore, elucidating the role and mechanism of NRG-1/ErbB in tissue engineering is helpful to provide theoretical basis for the development of tissue engineering and the clinical transformation of regenerative medicine.

The application of computer-aided design and computer-aided manufacturing (CAD/CAM) in the fabrication of complete dentures has gradually matured, and there have been multiple commercialized digital denture systems widely used in clinic. However, different systems have some differences in devices, number of visits, operating procedures and so on. Mastering the characteristics of different systems is helpful for physicians to choose the most suitable system and improve the efficiency and efficacy of treatment. Therefore, this paper selects several digital systems commonly used in clinic to explain and compare their special devices and technical characteristics, and to review and prospect the research progress of digital complete dentures.

By reviewing the literature of the study on the artery in maxillary sinus region, this paper summarized and analyzed physiological and anatomical characteristics of alveolar antral artery, such as the detection rate, diameter and course, so as to provide some references for clinical treatment and reduce the risk of hemorrhage during maxillary sinus elevation surgery.