Quantitative evaluation of vertical control in orthodontic camouflage treatment for skeletal class II with hyperdivergent facial type.

BACKGROUND: In this study, we sought to quantify the influence of vertical control assisted by a temporary anchorage device (TAD) on orthodontic treatment efficacy for skeletal class II patients with a hyperdivergent facial type and probe into the critical factors of profile improvement. METHODS: A total of 36 adult patients with skeletal class II and a hyperdivergent facial type were included in this retrospective case-control study. To exclude the effect of sagittal anchorage reinforcement, the patients were divided into two groups: a maxillary maximum anchorage (MMA) group (N = 17), in which TADs were only used to help with anterior tooth retraction, and the MMA with vertical control (MMA + VC) group (N = 19), for which TADs were also used to intrude the maxillary molars and incisors. The treatment outcome was evaluated using dental, skeletal, and soft-tissue-related parameters via a cephalometric analysis and cast superimposition. RESULTS: A significant decrease in ANB (P < 0.05 for both groups), the retraction and uprighting of the maxillary and mandibular incisors, and the retraction of protruded upper and lower lips were observed in both groups. Moreover, a significant intrusion of the maxillary molars was observed via the cephalometric analysis (- 1.56 ± 1.52 mm, P < 0.05) and cast superimposition (- 2.25 ± 1.03 mm, P < 0.05) of the MMA + VC group but not the MMA group, which resulted in a remarkable decrease in the mandibular plane angle (- 1.82 ± 1.38°, P < 0.05). The Z angle (15.25 ± 5.30°, P < 0.05) and Chin thickness (- 0.97 ± 0.45°, P < 0.05) also improved dramatically in the MMA + VC group, indicating a better profile and a relaxed mentalis. Multivariate regression showed that the improvement in the soft tissue was closely related to the counterclockwise rotation of the mandible plane (P < 0.05). CONCLUSIONS: TAD-assisted vertical control can achieve intrusion of approximately 2 mm for the upper first molars and induce mandibular counterclockwise rotation of approximately 1.8°. Moreover, it is especially important for patients without sufficient retraction of the upper incisors or a satisfactory chin shape.

Microbiological Advances in Orthodontics: An Overview and Detailed Analysis of Temporary Anchorage Devices.

Dental biofilm is the initiating factor of oral diseases, such as periodontitis and caries. Orthodontic treatment could alter the microbiome structure balance, and increase the risk of such diseases. Furthermore, fixed appliances can induce temporary changes in the microbiome community, and the changes that clear aligners bring are smaller by comparison. Temporary anchorage devices (TADs) are skeletal anchorages that are widely used in orthodontic treatment. Microorganisms affect the occurrence and development of inflammation surrounding TADs. At present, existing researches have verified the existence of plaque biofilm on the surface of TADs, but the formation of plaque biofilm and plaque composition under different stable conditions have not been fully understood. The development of high-throughput sequencing, molecular biology experiments, and metabonomics have provided new research ideas to solve this problem. They can become an effective means to explore the microbiome surrounding TADs.

A New HIV-1 K28E32-Reverse Transcriptase Variant Associated with the Rapid Expansion of CRF07_BC among Men Who Have Sex with Men.

HIV-1 CRF07_BC originated among injection drug users (IDUs) in China. After diffusing into men who have sex with men (MSM), CRF07_BC has shown a rapid expansion in this group; however, the mechanism remains unclear. Here, we identified a new K28E32 variant of CRF07_BC that was characterized by five specific mutations (E28K, K32E, E248V, K249Q, and T338S) in reverse transcriptase. This variant was mainly prevalent among MSM, and was overrepresented in transmission clusters, suggesting that it could have driven the rapid expansion of CRF07_BC in MSM, though founder effects cannot be ruled out. It was descended from an evolutionary intermediate accumulating four specific mutations and formed an independent phylogenetic node with an estimated origin time in 2003. The K28E32 variant was demonstrated to have significantly higher in vitro HIV-1 replication ability than the wild type. Mutations E28K and K32E play a critical role in the improvement of in vitro HIV-1 replication ability, reflected by improved reverse transcription activity. The results could allow public health officials to use this marker (especially E28K and K32E mutations in the reverse transcriptase (RT) coding region) to target prevention measures prioritizing MSM population and persons infected with this variant for test and treat initiatives. IMPORTANCE HIV-1 has very high mutation rate that is correlated with the survival and adaption of the virus. The variants with higher transmissibility may be more selective advantage than the strains with higher virulence. Several HIV-1 variants were previously demonstrated to be correlated with higher viral load and lower CD4 T cell count. Here, we first identified a new variant (the K28E32 variant) of HIV-1 CRF07_BC, described its origin and evolutionary dynamics, and demonstrated its higher in vitro HIV-1 replication ability than the wild type. We demonstrated that five RT mutations (especially E28K and K32E) significantly improve in vitro HIV-1 replication ability. The appearance of the new K28E32 variant was associated with the rapidly increasing prevalence of CRF07_BC among MSM.

Mechanical force-promoted osteoclastic differentiation via periodontal ligament stem cell exosomal protein ANXA3.

Exosomes play a critical role in intracellular communication. The biogenesis and function of exosomes are regulated by multiple biochemical factors. In the present study, we find that mechanical force promotes the biogenesis of exosomes derived from periodontal ligament stem cells (PDLSCs) and alters the exosomal proteome profile to induce osteoclastic differentiation. Mechanistically, mechanical force increases the level of exosomal proteins, especially annexin A3 (ANXA3), which facilitates exosome internalization to activate extracellular signal-regulated kinase (ERK), thus inducing osteoclast differentiation. Moreover, the infusion of exosomes derived from PDLSCs into mice promotes mechanical force-induced tooth movement and increases osteoclasts in the periodontal ligament. Collectively, this study demonstrates that mechanical force treatment promotes the biogenesis of exosomes from PDLSCs and increases exosomal protein ANXA3 to facilitate exosome internalization, which activates ERK phosphorylation, thus inducing osteoclast differentiation. Our findings shed light on new mechanisms for how mechanical force regulates the biology of exosomes and bone metabolism.

Stem Cells From Human Exfoliated Deciduous Teeth Alleviate Liver Cirrhosis via Inhibition of Gasdermin D-Executed Hepatocyte Pyroptosis.

Liver cirrhosis represents a type of end-stage liver disease with few effective therapies, which was characterized by damaged functional liver tissue due to long-term inflammation. Gasdermin D (GSDMD)-executed programmed necrosis is reported to be involved in inflammation. However, the role of GSDMD in liver cirrhosis remains unclear. In this study, we used a CCl4-induced cirrhosis model and found stem cells from human exfoliated deciduous teeth (SHED) infusion showed profound therapeutic effects for liver cirrhosis. Mechanistically, NLRP3 inflammasome-activated GSDMD and its pyroptosis were upregulated in liver cirrhosis, while SHED infusion could suppress the expression of GSDMD and Caspase-1, resulting in reduced hepatocyte pyroptosis and inflammatory cytokine IL-1ß release. Consistently, SHED could inhibit the elevated expression of NLRP3, GSDMD and Caspase-1 induced by CCl4 treatment in vitro co-culture system, which was mediated by decreasing reactive oxygen species (ROS) generation. Moreover, the pyroptosis inhibitor disulfiram showed similar therapeutic effects for liver cirrhosis as SHED. In conclusion, SHED alleviates CCl4-induced liver cirrhosis via inhibition of hepatocytes pyroptosis. Our findings could provide a potential treatment strategy and novel target for liver cirrhosis.

SARS-CoV-2-triggered mast cell rapid degranulation induces alveolar epithelial inflammation and lung injury.

SARS-CoV-2 infection-induced hyper-inflammation links to the acute lung injury and COVID-19 severity. Identifying the primary mediators that initiate the uncontrolled hypercytokinemia is essential for treatments. Mast cells (MCs) are strategically located at the mucosa and beneficially or detrimentally regulate immune inflammations. In this study, we showed that SARS-CoV-2-triggered MC degranulation initiated alveolar epithelial inflammation and lung injury. SARS-CoV-2 challenge induced MC degranulation in ACE-2 humanized mice and rhesus macaques, and a rapid MC degranulation could be recapitulated with Spike-RBD binding to ACE2 in cells; MC degranulation altered various signaling pathways in alveolar epithelial cells, particularly, the induction of pro-inflammatory factors and consequential disruption of tight junctions. Importantly, the administration of clinical MC stabilizers for blocking degranulation dampened SARS-CoV-2-induced production of pro-inflammatory factors and prevented lung injury. These findings uncover a novel mechanism for SARS-CoV-2 initiating lung inflammation, and suggest an off-label use of MC stabilizer as immunomodulators for COVID-19 treatments.

An Overview of Anterior Repositioning Splint Therapy for Disc Displacement-related Temporomandibular Disorders.

Anterior repositioning splint (ARS) therapy is considered one of the most effective therapies for treating disc displacement-related temporomandibular disorders (TMDs), which account for a large proportion of TMD cases. Owing to the wide application of this therapy, the exact mechanism of remission has increasingly drawn attention. Given that practitioners have different views on ARS therapy, its indications are broadened, and operating methods diverged. This review attempts to provide an overview of ARS therapy and helps practitioners establish indications and suitable operating methods. Representative views in the past 10 years were summarised, and conclusions were drawn as follows: The mechanism of ARS therapy is mainly attributed to internal derangement correction, improvement of stress distribution and recently reported joint remodeling. It has an evident effect in the short term, and the most prevalent operating methods are protruding the mandible to the edge-to-edge position and wearing the ARS for 24 hours daily for 3-6 months. However, long-term stability is not optimal, and thus indications should be selected carefully. Notably, most of the clinical studies in this field are case analyses with low-quality evidence. Well-designed RCTs are required to further validate relevant theories.

Genetic Characterization of a Novel HIV-1 Second-Generation Recombinant Form (CRF01_AE/CRF07_BC) Identified in Yan'an City, China.

Owing to co-epidemic of CRF01_AE and CRF07_BC in China, increasing numbers of the second-generation recombinants between them have been identified especially among sexual population. In this study, we identified a unique CRF01_AE/CRF07_BC recombinants from a male HIV-1 positive individual (18YA004) infected by heterosexual contact in Yan'an city, Shaanxi province. The near full-length genome analyses showed 18YA004 was divided into six fragments by five breakpoints located in the pol, vpr, vpu, and nef gene, respectively. Three CRF01_AE segments (segments I, III, and V) were all clustered within the cluster 4a lineage, exclusively circulating among MSM in the northern China. Coupled with our previous finding of CRF01_AE/C recombinant in Yan'an city, the emergence of CRF01_AE/CRF07_BC strain further suggested coexistence of multiple HIV-1 genotypes here. Therefore, it is necessary to continue monitoring the molecular epidemiology of HIV-1 among high-risk groups to obtain a better understanding of the genetic complexity and transmission of HIV-1 in this region.

Genetic Characteristics of Three Unique Recombinant Forms of HIV-1 in Yunnan, China.

To explore the molecular epidemiological status of human immunodeficiency virus type 1 (HIV-1) in Yunnan, China, three HIV-1 near full-length genomes were amplified and sequenced from plasma samples that were collected from Burmese patients newly diagnosed with HIV-1 in Dehong Prefecture in Yunnan Province in 2017. Phylogenetic and bootscanning analyses revealed that all the sequences might be HIV-1 second-generation recombinant forms of circulating recombinant forms (CRF07_BC and CRF83_cpx) and unique recombinant forms. One of the sequences contained six CRF01_AE fragments, five subtype C fragments, and two subtype B fragments, which were separated by 12 breakpoints. These results revealed that the second-generation recombination of HIV-1 within different strains is still ongoing in Dehong, China. Systematic surveys and immediate interventions are urgently needed to prevent the formation of increasingly complex HIV-1 recombinant forms.

The Genetic Diversity of HIV-1 Within Antiretroviral-Naive Outpatients in Ganzhou, China.

To explore the molecular epidemiological status of human immunodeficiency virus type 1 (HIV-1) in Ganzhou, China, eight HIV-1-positive outpatients were recruited from July 5 to 21, 2018. Six HIV-1 near-full-length sequences were amplified and sequenced from the plasma samples that were collected before the patients' antiretroviral treatments. Phylogenetic and bootscan analyses revealed that one of the sequences was CRF01_AE, one was CRF55_01B, and two were CRF07_BC. Notably, one of the sequences was a unique recombinant form, and one of them was a second-generation recombinant form of CRF07_BC and subtype C. These results revealed that multiple HIV-1 subtypes are circulating in Ganzhou, China. Systematic surveys with large sample sizes are urgently needed to explore the exact molecular epidemiological characteristics and to trace the origins of HIV-1 in Ganzhou, China.

The Delivery of Extracellular Vesicles Loaded in Biomaterial Scaffolds for Bone Regeneration.

Extracellular vesicles (EVs) are heterogeneous nanoparticles actively released by cells that comprise highly conserved and efficient systems of intercellular communication. In recent years, numerous studies have proven that EVs play an important role in the field of bone tissue engineering (BTE) due to several advantages, such as good biosafety, stability and efficient delivery. However, the application of EVs therapies in bone regeneration has not been widely used. One of the major challenges for the application of EVs is the lack of sufficient scaffolds to load and control the release of EVs. Thus, in this review, we describe the most advanced current strategies for delivering EVs with various biomaterials for the use in bone regeneration, the role of EVs in bone regeneration, the distribution of EVs mediated by biomaterials and common methods of promoting EVs delivery efficacy with a focus on biomaterial properties.

Mechanical force modulates periodontal ligament stem cell characteristics during bone remodelling via TRPV4.

OBJECTIVES: Mechanical force plays an important role in modulating stem cell fate and behaviours. However, how periodontal ligament stem cells (PDLSCs) perceive mechanical stimulus and transfer it into biological signals, and thereby promote alveolar bone remodelling, is unclear. MATERIALS AND METHODS: An animal model of force-induced tooth movement and a compressive force in vitro was used. After force application, tooth movement distance, mesenchymal stem cell and osteoclast number, and proinflammatory cytokine expression were detected in periodontal tissues. Then, rat primary PDLSCs with or without force loading were isolated, and their stem cell characteristics including clonogenicity, proliferation, multipotent differentiation and immunoregulatory properties were evaluated. Under compressive force in vitro, the effects of the ERK signalling pathway on PDLSC characteristics were evaluated by Western blotting. RESULTS: Mechanical force in vivo induced PDLSC proliferation, which was accompanied with inflammatory cytokine accumulation, osteoclast differentiation and TRPV4 activation; the force-stimulated PDLSCs showed greater clonogenicity and proliferation, reduced differentiation ability, improved induction of macrophage migration, osteoclast differentiation and proinflammatory factor expression. The biological changes induced by mechanical force could be partially suppressed by TRPV4 inhibition. Mechanistically, force-induced activation of TRPV4 in PDLSCs regulated osteoclast differentiation by affecting the RANKL/OPG system via ERK signalling. CONCLUSIONS: Taken together, we show here that TRPV4 activation in PDLSCs under mechanical force contributes to changing their stem cell characteristics and modulates bone remodelling during tooth movement.

T cells participate in bone remodeling during the rapid palatal expansion.

Palatal expansion has been widely used for the treatment of transverse discrepancy or maxillae hypoplasia, but the biological mechanism of bone formation during this procedure is largely unknown. Osteoclasts, which could be regulated by T cells and other components of the immune system, play a crucial role in force-induced bone remodeling. However, whether T cells participate in the palatal expansion process remains to be determined. In this study, we conducted the tooth borne rapid palatal expansion model on the mouse, and detect whether the helper T cells (Th) and regulatory T cells (Treg) could affect osteoclasts and further bone formation. After bonding open spring palatal expanders for 3-day, 5-day, 7-day, and retention for 28-day, micro-computed tomography scanning, histologic, and immunofluorescence staining were conducted to evaluate how osteoclasts were regulated by T cells during the bone remodeling process. We revealed that the increased osteoclast number was downregulated at the end of the early stage of rapid palatal expansion. Type 1 helper T (Th1) cells and Type 17 helper T (Th17) cells increased initially and promoted osteoclastogenesis. Thereafter, the regulatory T (Treg) cells emerged and maintained a relatively high level at the late stage of the experiment to downregulate the osteoclast number by inhibiting Th1 and Th17 cells, which governed the new bone formation. In conclusion, orchestrated T cells are able to regulate osteoclasts at the early stage of rapid palatal expansion and further facilitate bone formation during retention. This study identifies that T cells participate in the palatal expansion procedure by regulating osteoclasts and implies the potential possibility for clinically modulating T cells to improve the palatal expansion efficacy.

Identification of a Novel HIV-1 Unique CRF01_AE/C Recombinant in Yan'an City, Shaanxi Province.

A wide variety of HIV-1 recombinants are constantly discovered in China. Comprehensively monitoring the genetic diversity of HIV-1 is very essential for understanding the molecular epidemiology and controlling the spread of the HIV-1 epidemic. In this study, we presented a novel HIV-1 unique CRF01_AE/C recombinant (19YA001) isolated from a female patient infected HIV-1 through heterosexual transmission in Yan'an city, Shaanxi province. The near full-length genome analyses showed 19YA001 was divided into two CRF01_AE and one C segments by two breakpoints observed in the vif/vpr region. To date, this is the first report revealing the characteristic of HIV-1 subtype in Yan'an city. And this unique recombinant strain might imply that the genetic diversity of HIV-1 in Yan'an city is complex. However, the sample size is too small. Further larger studies of HIV-1 molecular epidemiology are urgently needed to provide a better understanding of HIV-1 diversity and transmission in this region.

HIV-1 Drug Resistance in ART-Naïve Individuals in Myanmar.

BACKGROUND: Estimating the prevalence and characterizing the transmission of HIV-1 drug resistance in treatment-naïve individuals are very important in the prevention and control of HIV/AIDS. As one of the areas most affected by HIV/AIDS, few data are currently available for HIV-1 drug resistance in antiretroviral therapy (ART)-naïve individuals in Myanmar, which borders Yunnan, China. METHODS: HIV-1 pol sequences from ART-naïve HIV-1-infected individuals during 2008 and 2014 in Myanmar were retrieved from our previous studies. HIV-1 transmitted drug resistance (TDR) and susceptibility to antiretroviral drugs were predicted using the Stanford HIVdb program. HIV-1 transmission cluster (TC) was determined by Cluster Picker. RESULTS: A total of 169 partial pol sequences from ART-naïve HIV-1 positive Burmese were analyzed. The prevalence of TDR was 20.1%. CRF01_AE and BC recombinants appeared to have a higher prevalence of TDR than other subtypes. The V179D/T was found to be very common in the China-Myanmar border region and was involved in half of the transmission clusters formed by HIV-1 drug-resistance strains in this region. Comparison showed that drug-resistance mutation profile in Myanmar was very similar to that in Dehong prefecture of Yunnan. By further phylogenetic analysis with all available sequences from the China-Myanmar border region, four HIV-1 drug-resistance-related TCs were identified. Three of them were formed by Burmese long-distance truck drivers and the Burmese staying in Yunnan, and another was formed by Burmese injection drug users staying in Myanmar and Yunnan. These results suggest a potential transmission link of HIV-1 drug resistance between Myanmar and Yunnan. CONCLUSION: Given the high prevalence of TDR in Myanmar, and the potential risk of cross-border transmission of HIV-1 drug-resistant strains between Myanmar and Yunnan, China, ongoing monitoring of HIV-1 drug resistance in ART-naïve individuals will provide a guideline for clinical antiretroviral treatment and benefit the prevention and control of HIV/AIDS in this border region.

The Phylodynamics of Seasonal Influenza A/H1N1pdm Virus in China Between 2009 and 2019.

Since its first introduction into China in 2009, influenza A/H1N1pdm virus has undergone a rapid expansion and replaced the classical seasonal A(H1N1) virus. To characterize the ongoing evolution and national transmission dynamics of this virus, we analyzed 335 complete genome, 1259 HA, and 1043 NA sequences of the A/H1N1pdm strains detected in China. We found that the dN/dS value and relative genetic diversity of the A/H1N1pdm virus experienced a decrease from 2009 to 2017, and then a rapid increase during 2018-2019. Importantly, elevated relative genetic diversity was observed in the A/H1N1pdm and the A/H3N2 viruses, as well as two lineages (Victoria and Yamagata) of influenza B virus during 2018-2019, suggesting the simultaneous changes of these viruses in terms of genetic diversity might be associated with the recent large outbreak of seasonal influenza epidemic in China during 2018-2019. Fifteen amino acid mutations were found to be fixed along the main trunks of both HA and NA phylogenetic trees, and some of them are located in the antigen binding site or the receptor binding site. A sequential accumulation of mutations relative to the 2009-vaccine strain was observed in the circulating A/H1N1pdm strains during 2009-2016, while a rapid accumulation of mutations relative to the 2015-vaccine strain appeared in the emerging variants in 2017 shortly after the release of the vaccine. Multiple introductions of the A/H1N1pdm lineages into China were observed during 2009-2019, and East China and South China were found to serve as two major epicenters responsible for the national migration of the virus. In summary, these data provide important insights into the understanding of the evolution, epidemiology and transmission of the A/H1N1pdm virus, and highlight the importance of strengthening influenza surveillance in East China and South China.

Stem cells from human exfoliated deciduous teeth ameliorate concanavalin A-induced autoimmune hepatitis by protecting hepatocytes from apoptosis.

BACKGROUND: Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide, which emphasizes the urgent need to identify novel treatments. Stem cells from human exfoliated deciduous teeth (SHED), which are easy to obtain in a non-invasive manner, show pronounced proliferative and immunomodulatory capacities. AIM: To investigate the protective effects of SHED on concanavalin A (ConA)-induced hepatitis in mice, and to elucidate the associated regulatory mechanisms. METHODS: We used a ConA-induced acute hepatitis mouse model and an in vitro co-culture system to study the protective effects of SHED on ConA-induced autoimmune hepatitis, as well as the associated underlying mechanisms. RESULTS: SHED infusion could prevent aberrant histopathological liver architecture caused by ConA-induced infiltration of CD3+, CD4+, tumor necrosis-alpha+, and interferon-gamma+ inflammatory cells. Alanine aminotransferase and aspartate aminotransferase were significantly elevated in hepatitis mice. SHED infusion could therefore block ConA-induced alanine aminotransferase and aspartate aminotransferase elevations. Mechanistically, ConA upregulated tumor necrosis-alpha and interferon-gamma expression, which was activated by the nuclear factor-kappa B pathway to induce hepatocyte apoptosis, resulting in acute liver injury. SHED administration protected hepatocytes from ConA-induced apoptosis. CONCLUSION: SHED alleviates ConA-induced acute liver injury via inhibition of hepatocyte apoptosis mediated by the nuclear factor-kappa B pathway. Our findings could provide a potential treatment strategy for hepatitis.

Tryptophan Metabolism Activates Aryl Hydrocarbon Receptor-Mediated Pathway To Promote HIV-1 Infection and Reactivation.

Multiple cellular metabolic pathways are altered by HIV-1 infection, with an impact on immune activation, inflammation, and acquisition of non-AIDS comorbid diseases. The dysfunction of tryptophan (Trp) metabolism has been observed clinically in association with accelerated HIV-1 pathogenesis, but the underlying mechanism remains unknown. In this study, we demonstrated that the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, is activated by Trp metabolites to promote HIV-1 infection and reactivation. AHR directly binds to the HIV-1 5' long terminal repeat (5'-LTR) at the molecular level to activate viral transcription and infection, and AHR activation by Trp metabolites increases its nuclear translocation and association with the HIV 5'-LTR; moreover, the binding of AHR with HIV-1 Tat facilitates the recruitment of positive transcription factors to viral promoters. These findings not only elucidate a previously unappreciated mechanism through which cellular Trp metabolites affect HIV pathogenesis but also suggest that a downstream target AHR may be a potential target for modulating HIV-1 infection.IMPORTANCE Cellular metabolic pathways that are altered by HIV-1 infection may accelerate disease progression. Dysfunction in tryptophan (Trp) metabolism has been observed clinically in association with accelerated HIV-1 pathogenesis, but the mechanism responsible was not known. This study demonstrates that Trp metabolites augment the activation of aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, to promote HIV-1 infection and transcription. These findings not only elucidate a previously unappreciated mechanism through which cellular Trp metabolites affect HIV pathogenesis but also suggest that a downstream target AHR may be a potential target for modulating HIV-1 infection.

Local Administration of Stem Cells from Human Exfoliated Primary Teeth Attenuate Experimental Periodontitis in Mice.

OBJECTIVE: To evaluate the therapeutic effect of local injection of stem cells from human exfoliated primary teeth (SHED) on periodontitis in mice. METHODS: Fifteen female mice were randomly divided into three groups: normal control group, periodontitis group and SHED treatment group. A periodontitis model was established by ligating a 0.2 mm orthodontic ligation wire to the maxillary first molar. The SHED group was injected with SHED at 3 weeks post-ligation. All mice were sacrificed and their maxillae were dissected five weeks post-ligation. Clinical assessments, micro-computed tomography (micro-CT) scanning, and histologic examination were used to evaluate the outcome of tissue regeneration. RESULTS: Micro-CT analysis showed that SHED administration significantly increased periodontal regeneration and decreased the distance between the cemento-enamel junction and the alveolar bone crest. In addition, histopathological photomicrographs showed new regenerated bone, the number of TNF-α-positive, IFN-γ-positive and CD4+ cells decreased, and osteoclasts-positive decreased in the periodontal defect area in the SHED group compared with the periodontitis group. CONCLUSION: SHED administration suppresses the expression of inflammatory factors, inhibits the production of osteoclasts, and promotes the regeneration of periodontal tissues.