The ultimate treatment goal of periodontitis is the structural and functional regeneration of periodontium. However, existing methods for periodontal regeneration have difficulties in regenerating the hierarchical structure. Therefore, stem cell-based tissue engineering has attracted more and more attention for its advantages of self-renewal and multi-lineage differentiation potential. This review summarized the progress of research on periodontal tissue regeneration by combined biomaterials of dental-derived stem cells. It is pointed out that the application of autologous stem cell transplantation is limited by the donor source, and the subsequent research should focus on the development of multi-phase scaffold materials and the attempt to establish a stem cell bank.

Gingival recession could result in root exposure, dental hypersensitivity and poor aesthetics. It has been demonstrated that varieties of root coverage procedures can significantly improve gingival recession in short-term (≤6 months), of which coronally advanced flap combined with connective tissue graft is the gold standard technique for treatment of gingival recession. It could obtain the optimally complete root coverage and maintain long-term stability (≥2 years). However, clinical knowledge about the long-term effectiveness of the other alternative graft materials remain very limited. Based on the existing clinical evidence, this article reviews coronally advanced flap, coronally advanced flap combined with connective tissue graft or alternative graft materials, with particular attention to the long-term stability of them, in order to provide reference for the design of further clinical trials and the plan of clinical treatments.

OBJECTIVETo investigate the effect of naringin on the proliferation, differentiation and matrix mineralization of MC3T3-E1 cells in vitro.

METHODMC3T3-E1 cell lines were taken in vitro model. CCk-8 method was used to observe the proliferation of MC3T3 cells. Lactic acid dehydrogenase cytotoxicity (LDH) test was used to observe the cell toxicity. Bone morphogenetic protein-2 (BMP-2), alkaline phosphatase (ALP) and osteocalcin (OC) were used to observe the cell differentiation. Von kossa calcification staining method was used to observe the cell calcification.

RESULTSThe high dosages of the naringin could promote the proliferation of MC3T3-E1 cells at both 12 h and 24 h. While, low dosages did not show the same capability. LDH test showed that the cytotoxicity percentages in all six naringin treated groups were quite low. BMP-2 cytoimmunochemistry test showed that the three naringin treated group (10, 1, 0.1 micromol x L(-1)) showed higher brown coloration in cytoplasm than the control group at both 24 h and 48 h. 1, 0.1 micromol x L(-1) naringin raised ALP activity of MC3T3-E1 cells at 48 h (P < 0.05). Meanwhile, 0.1 micromol x L(-1) naringin increased the ALP activity at 72 h (P < 0.05). 10 and 1 micromol x L(-1) naringin increased the capability of MC3T3-E1 cell to synthesize osteocalcin during 8th - 12th dsince adding the medicine (P < 0.05). Naringin did not show the positive effects on cell calcification.

CONCLUSIONSNaringin could promote proliferation and differentiation of MC3T3-E1 cells.

Animals ; Bone Morphogenetic Protein 2 ; metabolism ; Calcification, Physiologic ; drug effects ; Cell Differentiation ; drug effects ; Cell Line ; Cell Proliferation ; drug effects ; Flavanones ; pharmacology ; Mice ; Osteoblasts ; cytology ; drug effects ; metabolism ; Osteocalcin ; metabolism

Research have indicated that inadequate keratinized tissue has a negative effect on patient oral hygiene, resulting in peri-implant inflammation. It has been recommended that an apically repositioned flap alone or in combination with autogenous soft tissue grafts can increase the width of keratinized mucosa around dental implants, which promotes long term peri-implant health. This review summarized research progress on augmentation techniques of keratinized tissue arround implants in recent years, so as to provide reference for clinical practice and research design in the future.

In previous studies,the two-way relationship between periodontitis and diabetes has been established.Subgingival flora and salivary flora are often used to explore the relationship between the microbiome in diabetes and periodontitis.In recent years,the development of sequencing technology has provided a broader and deeper approach to exploring the impact of diabetes on oral microbi-ome.This review aims to summarize the effects of diabetes on subgingival flora and salivary flora in patients with periodontitis,so as to provide reference for clinical diagnosis and treatment.

Objective To investigate the effect of local delivery of delta 12-prostaglandinJ2-loaded poly(lactic-co-glycolic acid) (△ 12-PGJ22-NC) on growth factors expression and bone formation.Methods △ 12-PGJ2-NC was prepared by the emulsion solvent diffusion method.The physical and chemical properties of the nanoparticles were evaluated by particle size analysis,transmission electron microscopy,drug-loading ratio and the in vitro release study.Then standardized transcortical defect(5.0 mm × 1.5 mm) was conducted in the femur of 48 male Wistar rats which were randomly divided into four groups(n=12),S,K,F,and N.Thirty microliter of saline(S),unloaded nanoparticles(K),△ 12-PGJ2(F) and △ 12-PGJ2-NC(N) in a collagen vehicle were delivered inside a titanium chamber fixed over the defect.Then,four subgroups were randomly divided in each group named as D3,D7,D14,and D28(n=3) according to the days 3,7,14,and 28 after the surgery.At days 3,7,14,and 28,the mRNA expression of the bone morphogenetic protein-6(BMP-6),platelet-derived growth factor-B(PDGF-B) in defect aera was analyzed by real time quantitive-polymerase chain reaction(qRT-PCR).The protein expression of the BMP-6 and Ephrin-B2 was evaluated by Western blotting.HE staining was employed to reveal new bone formation in weeks 2 and 4.Results △ 12-PGJ2-NC appeared opalescent white and remained relatively stable,with an average particle size of (135.2±0.85) nm.The images from transmission electron microscopy showed that △ 12-PGJ2-NC was spherical in shape and homogeneously distributed.The encapsulation efficiency of △ 12-PGJ2 with the poly(lactic-co-glycolic acid) (PLGA) nanocapsules was about 92％.The in vitro release of △ 12-PGJ2-NC at 37 ℃ showed a sustained fashion and the average accumulated amount was 30％,52％,77％,91％,and 98％ respectively,at 0.5,1,2,4 and 6 h.Compared with the animals treated with saline,after dose of 100 mg/L △ 12-PGJ2 and △ 12-PGJ2-NC apllication,the mRNA expression level of BMP-6,PDGF-B increased significantly(P＜0.05,P＜ 0.001).The protein expression of BMP-6,Ephrin-B2 also was up-regulated.Histomorphometry revealed that new bone formation increased at the same dose of 100 mg/L.But the unloaded nanoparticles did not have the same effect(P＞0.05).Conclusions A stable△ 12-PGJ2 loaded nanoparticle was successfully prepared.△ 12-PGJ2-NC may upregulate the expression of BMP-6,PDGF-B and Ephrin-B2,and promote new bone formation in bone defect area.

Periodontal disease is individual-specific and site-specific. Therefore, the periodontal sequence treatment plan should not only base on the patient's condition and disease progression, but also take local conditions into account. This paper reports the whole periodontal therapy of a young patient with stage Ⅳ grade C generalized periodontitis with longitude observation of 7 years. We analyze the factors between extraction and maintenance of hopeless teeth from individual-specific and site-specific perspectives. We also discuss the importance of keratinized mucosa around implants in order to provide reference for the treatment of periodontitis.

Pyroptosis is a pro-inflammatory form of programmed cell death that has been gradually recognized in recent years. It plays an important role in recognizing the invasion of exogenous pathogens and sensing endogenous danger signals. The initiation of pyroptosis depends on the activation of intracellular inflammasome and its downstream caspases, as well as the active fragment of the key protein Gasdermin. The invasion of periodontal pathogens induces an inflammatory response of the host, involving the activation of inflammasome and triggering pyroptosis as well. Meanwhile, it leads to the release of a large number of inflammatory cytokines such as interleukin (IL)-1β and IL-18 to amplify the inflammatory response and mediate periodontal tissue destruction eventually. This article reviews the research progress of the signaling pathways of pyroptosis, as well as its mechanism induced by periodontal pathogens and the mechanism of periodontal tissue damage in periodontitis in order to provide new targets and ideas for the prevention and treatment of periodontitis.

Periodontitis is an inflammation that occurs in the supporting tissues around teeth with plaque biofilm as the starting factor. Periodontitis is closely related to many systemic diseases, among which the relationship between periodontitis and diabetes is the most widely reported. A cohort study is an essential clinical research method to explore the etiology. Large, well-conducted prospective cohort studies have high power, which can provide important clinical evidence for the impact of periodontitis on blood sugar control, incidence rate and complications of diabetes mellitus. Periodontitis is associated with the deterioration of glycemic control. At present, there is moderate evidence that nonsurgical periodontal treatment can significantly improve the blood sugar level of diabetes patients with periodontitis compared with no periodontal treatment. Studies on the impact of periodontitis on the incidence rate of diabetes lack consistent conclusions because of different population backgrounds. The evidence regarding whether periodontitis affects the incidence rate of diabetes complications is relatively limited. Therefore, well-designed cohort studies are needed to provide high-quality clinical evidence.

Objective:To evaluate the effects of photodynamic therapy (PDT) in extraction sockets of periodontally compromised molars on soft tissue healing, postoperative pain, bone density and bone height changes.Methods:This study is a single-center, single-blind, randomized controlled superiority clinical trial. Thirty-eight periodontally compromised molars requiring extraction in patients attending the Department of Periodontology, Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, from December 2022 to September 2023 were included, and randomly assigned to PDT group and control group. The control group received routine debridement after extraction, while PDT group received routine debridement followed by PDT. The bucco-lingual and mesio-distal wound distances at 7 and 14 d after extraction were measured, and then the wound closure rates were calculated. Evaluating the soft tissue healing indexes at 7 and 14 d after extraction. The visual analogue scale was used to assess the pain level at 6 h, 1 d, 2 d, and 3 d after tooth extraction. Apical radiographs were taken immediately and 2 months after extraction in order to compare the changes of the bone density and height.Results:The wound closure rate at 1 week was (78.08±5.45)% in PDT group and (71.03±6.82)% in control group, with significant differences ( P<0.01). The wound closure rate at 2 weeks in PDT group [(85.88±3.84) %] was significantly higher than that in the control group [(81.66±3.79) %] ( P<0.01), but did not reach the superiority value of the superiority test (superiority value=10%, 95% CI at 1 week: 3.00%-11.12%, 95% CI at 2 weeks: 1.71%-6.73%). The soft tissue healing index of PDT group at 1 week was significantly better than the control group ( P<0.05), but there was no significant difference between the two groups at 2 weeks ( P>0.05). There was no significant difference between the two groups in terms of postoperative pain at 6 h, 1 d, 2 d and 3 d as well as in bone density and height changes at 2 months after tooth extraction ( P>0.05). Conclusions:PDT could promote soft tissues healing to some extent, but did not provide additional assistance in the healing of extraction sockets of periodontally compromised teeth. PDT did not show benefits on postoperative pain, changes of the bone density and bone height after tooth extraction.