Objective：To observe the changes of autophagy levels after delayed tooth replantation in rats and investigate the effect of autophagy in inflammatory root resorption after delayed tooth replantation. Methods： Twenty-four 4-week-old SD rats were divided into different groups. Maxillary first molars were extracted, dried for 30 minutes and then replanted into the alveolar sockets. Rats were sacrificed on day 1, 3, 7 and 28 after surgery, the inflammation infiltration situation, root resorption situation, expression of inflammatory cytokines, TNF-α and IL-1β, and expression of autophagy proteins LC3B and Beclin-1 were detected by tissue staining. Immunofluorescence staining was performed on human periodontal ligament fibroblasts (hPDLFs) treated with LPS to detect the expression of LC3B and Beclin1 at different time points. Meanwhile, the inflammation and autophagy-related gene expression in hPDLFs treated with LPS and autophagy promoter (Rapamycin) or autophagy inhibitor (chloroquine) was examined through real-time RT-PCR. Results：Massive inflammatory cell infiltration and inflammatory cytokines TNF-α and IL-1β around the root were observed on the 1st and 3rd day after surgery. On the 7th day, inflammatory infiltration level increased gradually and increased secretion of TNF-α and IL-1β was detected through immunohistochemical staining. The TRAP staining result showed obvious inflammatory resorption on the 7th day. The inflammation alleviated on the 28th day. During this process, autophagy proteins LC3 and Beclin-1 increased significantly on the 1st day after surgery, then declined on the 3rd and 7th day and increased again on the 28th days. In vitro experiments, autophagy proteins LC3B and Beclin-1 were activated in hPDLFs after LPS 24h stimulation, while inhibited after 72h LPS stimulation. The trends of autophagy proteins in vitro were consistent with the in vivo results. Expression of inflammation genes were significantly reduced in hPDLFs treated with autophagy promoter and LPS. Conclusions：Autophagy participates in the development of root inflammatory resorption after delayed tooth replantation, and may play a protective role.

Objective: To evaluate the influence of TiO2 nanotubes with different diameters on periodontal ligament stem cells (PDLSCs) biological changes. Methods: TiO2 nanotubes with different diameters were prepared by means of anodic oxidation at 5, 10 and 20?V voltage on the smooth titanium surface. The samples were divided into smooth titanium group (Ti), 5 V nanotube group (NT5), 10 V nanotube group (NT10) and 20 V nanotube group (NT20). The PDLSCs were obtained using the limiting-dilution technique, and then cultured on different diameters TiO2 nanotubes. The morphology of PDLSCs was observed by using FE-SEM. The cells adhesion was observed by Hoechst staining. The cells’ ALP activity was detected by ALP kit. Sirius red staining and Alizarin red staining were used to observe the collagen secretion and the sample surface extracellular matrix mineralization, respectively. Real time quantitative PCR was employed to detect the cells’ osteogenic and periodontal related genetic level. Results: The ALP staining experiment showed stronger activity in NT5 and NT20 groups than that in Ti group. A large number of mineralized nodules were formed on the surfaces of NT10 groups. TiO2 nanotubes morphology promoted the up-regulation of ALP, FN (NT5 and NT5 at 14 d) and RUNX2 (at 7 d) expression. Conclusions: Different diameters TiO2 nanotube morphology induced the PDLSCs to form different cell cytoskeletons and promoted the early adhesion, collagen secretion and related genes expression of PDLSCs.

Objective： To explore the effect of gamma secretase inhibitor (Semagacestat) on osteoclast formation and bone resorption induced by RANKL and its mechanism. Methods：Bone marrow cavity macrophages of 5 weeks old C57 mice were extracted for culture. IC50 of Semagacestat on macrophages was calculated by MTT to determine the safe drug concentration.The effect of Semagacestat on osteoclast formation was evaluated by osteoclast formation, TRAP staining and bone resorption test.RT-PCR was used to detect gene expression related to osteoclast formation.Western blot analysis of expression of proteins associated with Notch signaling pathway was also tested. Results：The 24h, 48h and 96h IC50 of Simasit on macrophages were 6.03, 5.79 and 5.18μmol/L, respectively. Trap staining showed that the number of osteoclasts formed was (209±8) for each well in the control group, and (183±14) for each well, (91±10) for each well, and (22±7) for each well in the Semagacestat 100, 200, and 400 nmol/L dosing groups, respectively(P < 0.05). In vitro bone resorption results showed that the percentage of bone resorption area in blank control group was (93.3±3.0)%, and the percentage of bone resorption area in Semagacestat 100, 200 and 400 nmol/L dosing groups was (80.6±6.6)%, (52.2±6.6)%, (27.4±5.8)%, respectively (P<0.05). RT-PCR results showed that the expressions of osteoclast related gene: C-fos, TRAP, Cath-K and NFATC1 were significantly decreased with the increase of the concentration of Semagacestat (P<0.05). Western Blot results showed that Cleaved-Notch1, NFATc1, and Hes1 expression decreased in the Semagacestat group compared to the control group (P<0.05). Conclusions:By inhibiting the activation of Notch pathway, Semagacestat inhibits the formation and bone resorption of osteoclasts, and may have a potential therapeutic effect on osteoarthritis.

Objective:To observe the effects of infection induced by Fusobacterium nucleatum (F. nucleatum) on the proliferation and infiltration of tongue squamous cell carcinoma cell line Cal-27. Methods:Supernatant from THP-1 cells differentiated macrophages stimulated with F. nucleatum (multiplicity of infection was 100:1) for 24 h was collected, and supernatants from unstimulated THP-1 cells differentiated macrophages and THP-1 cells were collected as controls. Cal-27 cells were co-cultured with the above-mentioned supernatants and Cal-27 cells proliferation was detected by CCK-8 method. Migration of Cal-27 cells were evaluated by scratch assay. Expressions of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were detected by ELISA. Results: F. nucleatum-induced macrophages conditioned medium reduced the proliferation but promoted the migration rate of Cal-27 cells in comparison with two control groups (P<0.05). The levels of TNF-α and IL-6 in macrophages stimulated with F. nucleatum were significantly higher than those without any stimulations (P<0.05). Conclusions:Stimulation of macrophages with F. nucleatum promoted TNF-α and IL-6 production, which may promote the migration but inhibit the proliferation of Cal-27 cells.

Objective：To compare the difference of implant and cortical bone stress value and the deformation value of titanium frame, in the design of All-on-Four and maxillary sinus floor augmentation with varies bone qualities, using finite element analysis in maxillary edentulous with insufficient bone mass in posterior tooth area. Methods:The CBCT data of a maxillary edentulous was selected to establish the solid models of D2, D3 and D4 bone quality. Two implant schemes were designed under each kind of bone quality, and a total of 12 models were applied 200 N vertical load on both posterior teeth with or without cantilever. Then, the von Mises stress values of implants and cortical bones and the deformation of titanium frame were calculated and statistically analyzed. Results:The von Mises stress of implant and cortical bone and the deformation of titanium frame with cantilever were significantly higher than those without cantilever, and the difference was statistically significant (P＜0.05). The von Mises stress of implant and cortical bone and the deformation of titanium frame in maxillary sinus floor augmentation group were lower than those in All-on-Four group, and the difference was statistically significant (P＜0.05). When the bone type was D4, the von Mises stress value of implant and cortical bone and the deformation of titanium frame were the largest. With the increase of bone quality, the von Mises stress value of implant and cortical bone and the deformation of titanium frame decreased gradually. Conclusions:The maxillary sinus floor augmentation showed more favorable biomechanical behavior than All-on-Four, which was suitable for all kinds of bone qualities. The increase of bone quality was beneficial to the overall stress distribution. When the bone type was D2, we could consider choosing All-on-Four for repair, but the cantilever should be reduced oravoided. When the bone type was D4, the All-on-Four technique should be used cautiously.

Objective：To evaluate the clinical effects of pulp revascularization of the immature permanent teeth with periapical lesions or pulp necrosis caused by the trauma or the dens evaginatus. Another purpose of the present study was to investigate the factors which may affect the treatment. Methods:66 cases of periapical lesions or pulp necrosis in immature permanent teeth were collected and treated by pulp revascularization. Mimics software was used to reconstruct a three-dimensional model of the periapical lesion before and after the treatment of the affected tooth. Then the volume of the apical lesions were measured. Dolphin software was used to measure the root length, the thickness of the root canal wall and apical foramen size before and after the treatment of the affected teeth. And to evaluate the factors which may affect the treatment. Results:According to the efficacy assessment criteria, 40 teeth were evaluated as "cured" (60.6%), 24 teeth as "improved" (36.4%), and two teeth as "ineffective" (3%). The preoperative inflammatory status significantly affected the root development (P<0.05). Conclusions:Pulp revascularization effectively promoted the healing of periapical lesions and achieved continuous root development. The preoperative inflammatory status can affect the root development.

Objectives:To analyze the effect of covering oral prosthesis membrane in apical resection of different bone defect areas. Methods: The shadow of digital periapical radiographs of 20 patients with bone defect covered by oral restorative membrane during apicectomy were measured before and 6 months after operation, and the healing of the lesions was analyzed combined with clinical manifestations. According to the diameter range (x) of the apical shadow of the 28 teeth before operation, they are divided into 4 groups: x＜4 mm, 4 mm≤x＜6 mm, 6 mm≤x＜8 mm, x≥8 mm. Results: The disappearance of clinical symptoms or imaging manifestations of reduction or disappearance of the periapical transmission area was regarded as success. 19 patients and 26 teeth were successfully treated. Among them, the failure of 1 case and 2 teeth belonged to the fourth group. The clinical manifestations were as follows: There is still discomfort on percussion, and discomfort on palpation. X-ray film shows that the shadow of the root tip has not been reduced. Conclusion: In the case of apical shadow less than 8 mm, it is better to cover the defect area with prosthodontic membrane.

Objective:To study the changes of multiple roots teeth in alveolar bone morphology in the implant area after immediate implantation by different depth. Methods: 44 teeth were selected from 38 patients who had been implanted for the previous multiple roots teeth. The cases were implanted from different depth in the middle of multiple roots with bone grafts and was divided into 4 groups- 0,1,2,3 mm below the bone by height of cervical border of implant neck. The CBCT images were took for immediate plant and 6 months later, reconstruct the 3-D images of plantation area and measure alveolar ridge width (5 planes), alveolar ridge width in labial and buccal (4 planes),lingual and palatal side (4 planes) with Simplant software. The morphology of alveolar bone in the planted area was analyzed statistically after immediate planting. Results: The width morphology of alveolar bone in the planted area was (1.158 0.567) mm, (0.676 0.390) mm, (0.391 0.257) mm, (0.163 0.149) mm, (0.053 0.083) mm in 5 measurement plane between immediate plant and 6 months later (P<0.01). The width morphology of alveolar bone in buccal side was (0.701 0.382) mm, (0.436 0.274) mm, (0.274 0.178) mm, (0.121 0.115) mm in 4 measurement plane (P<0.01). The width morphology of alveolar bone in lingual or palatal side was (0.448 0.308) mm, (0.233 0.170) mm, (0.119 0.119) mm, (0.041 0.056) mm in 4 measurement plane (P<0.01). The width morphology was different significantly between immediate plant and 6 months by different planting depths, The bone absorption was highest in the subosseous 0 mm group and the subosseous 1 mm group, the subosseous 2 and 3 mm group had less bone absorption (P<0.05). Conclusions: The alveolar bone width of the implanted area all decreased when multiple roots teeth were implanted immediately, and bone absorption mainly occurred in the neck of the implant; from the neck of the implant to the root, the alveolar bone absorption becomes less and less. Implantation depth of immediate implantation of multiple roots teeth should be 2 mm below bone.

Oral implant longevity and function rely on osseointegration and soft tissue integration ,soft tissue barrier protects the underlying hard tissue structures and the implant itself from oral polluted environment, which is of great significance to the long-term stability of the implant and the maintenance of soft tissue aesthetic effects.Implant surface morphology can affect soft tissue integration,the purpose of this review is to introduce the effect of titanium surface nano-morphology on epithelial cells and relevant datas.The differences between nanoscale and microscale implant surface modification were discussed, with emphasis on the methods and understandings to achieve specific functions of epithelial cells through nanotechnology.

Periodontitis is a chronic infectious disease caused by plaque microorganisms, which often leads to progressive destruction of periodontal supporting tissue. Its clinical manifestations include gingival inflammation, periodontal pocket formation, loss of attachment and alveolar bone resorption. It is the primary cause of adult tooth loss. Plaque biofilm, as the initiation factor of periodontitis, is an essential factor causing periodontitis. Dental plaque biofilm is the basis of survival, metabolism and pathogenicity of oral bacteria, which is composed of many architectural ecological groups growing in order with each other. It is important to study the formation of dental plaque biofilm for the prevention and treatment of periodontitis. Not all bacteria in the dental plaque biofilm can directly adhere to the surface of the acquired film. According to the colonization time, the bacteria can be divided into early, middle and late colonization bacteria. Fusobacterium nucleatum (f.nucleatum), as a intermediate colonizing bacterium, is the bridge bacterium connecting the early and late colonizing bacteria, which has important significance in the formation process of dental plaque biofilm. In this paper, the role of Fusobacterium nucleatum in the formation process of dental plaque biofilm is summarized.

Resolvins is a novel endogenous anti-inflammatory and pro-inflammatory lipid mediator that shows its potent biological role in multiple disease models. Some studies have found that resolvins is effective in the prevention and treatment of periodontitis and has a good clinical application prospect. In this paper, the anti-inflammatory effect of resolvins and its application in periodontitis are discussed.

How to shorten the time and cycle of orthodontic treatment has become a common concern of patients and doctors. Before, accelerate orthodontic tooth movement method is more, for the surgical treatment of different kinds of research, so this article will from the periodontal ligament with zhang/alveolar bone with zhang, bone cortex dissection, the dissection, piezoelectric micro perforation and bone surgery first five aspects to the current confirmed the surgical method can speed up the orthodontic tooth movement and its mechanism were reviewed.

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