Objective To compare the periodontally accelerated osteogenic orthodontics(PAOO)effects of corticotomy with full mu-coperiosteal flap(flapped corticotomy)and corticotomy-only on accelerating orthodontic tooth movement.Methods A total of 60 healthy male SD rats(weighing 180-200 g)were selected and randomly divided into three groups.There were 20 rats each in the flapped corticotomy group,the corticotomy-only group,and the control group.After applying orthodontic instruments,5 rats each in the surgical group and the control group were killed by excessive anesthesia on 0,1,3,and 7 days after tooth movement.The tooth move-ment distances of the rats in the control group and the experimental group were counted,and immunohistochemical staining was per-formed to observe the corresponding molecular biological changes.Results There was no significant difference in accelerating ortho-dontic tooth movement between the flapped corticotomy group and the corticotomy-only group.Compared with traditional orthodontic tooth movement,both the flapped corticotomygroup and the corticotomy-only group could bring an increase in the expression of RANKL on the pressed periodontal side while there was no significant difference between the two experimental groups.Both the flapped corticot-omy and non-flapped corticotomy could enlarge the area of tissue formation in the periodontal tension zone,and still there was no signif-icant difference between the two surgical methods.Compared with traditional orthodontic tooth movement,both the flapped corticotomy group and the corticotomy-only group could lead to an increase in ALP,OCN and OPN expression on the periodontal tension zone.Conclusion Both flapped corticotomy and corticotomy play a significant role in accelerating orthodontic tooth movement and promoting alveolar bone formation in the early stage.Both surgical methods of PAOO can provide more efficient and stable biological support for orthodontic treatment.

Objective To investigate the effects and molecular mechanisms of ginsenoside Rg1(GSRG1)on the proliferation,mi-gration,and inflammatory cytokine expression of human gingival fibroblasts(HGFs)induced by lipopolysaccharide(LPS).Methods HGFs were isolated and cultured using the tissue block method.The effects of different concentrations of LPS(0,1,5,10,20μg/mL)on inflammatory cytokines in HGFs were detected by ELISA.Cells were divided into three groups:control group(no treat-ment),LPS group(20 μg/mL LPS),and LPS+GSRG1 group(20 μg/mL LPS and 100 mg/L GSRG1).Cell proliferation was detec-ted by cell counting kit-8(CCK-8);cell migration was assessed by Transwell assay;intracellular reactive oxygen species(ROS)lev-els were compared using flow cytometry;and the expression levels of TNF-α,IL-6,NLRP3,p-p38,and p38 proteins were detected by Western blot.Results LPS concentrations of 5,10,and 20 μg/mL significantly increased the expression of IL-6 and TNF-α in HGFs(P＜0.05),with 20 μg/mL showing the strongest pro-inflammatory effect.Compared with the control group,there was no notable difference in the proliferation of HGFs in the LPS group at Day 1 and 2.However,on Day 3,4 and 5,decreased cell proliferation,re-duced migration,significantly increased ROS levels(P＜0.001),elevated protein expression of TNF-α,IL-6,and NLRP3(P＜0.001),and reduced p-p38 protein expression(P＜0.001)were exhibited.Compared with the LPS group,the LPS+GSRG1 group showed significantly enhanced cell proliferation and migration(P＜0.05),reduced ROS levels,decreased protein expression of TNF-α,IL-6,and NLRP3,and increased p-p38 protein expression(P＜0.001).There was no significant change in p38 expression among the three groups.Conclusion GSRG1 can alleviate the inhibitory effects of LPS on the proliferation and migration of HGFs and inhibit the inflammatory response,potentially through mechanisms involving p-p38 protein regulation.

Objective To compare the periodontally accelerated osteogenic orthodontics(PAOO)effects of corticotomy with full mu-coperiosteal flap(flapped corticotomy)and corticotomy-only on accelerating orthodontic tooth movement.Methods A total of 60 healthy male SD rats(weighing 180-200 g)were selected and randomly divided into three groups.There were 20 rats each in the flapped corticotomy group,the corticotomy-only group,and the control group.After applying orthodontic instruments,5 rats each in the surgical group and the control group were killed by excessive anesthesia on 0,1,3,and 7 days after tooth movement.The tooth move-ment distances of the rats in the control group and the experimental group were counted,and immunohistochemical staining was per-formed to observe the corresponding molecular biological changes.Results There was no significant difference in accelerating ortho-dontic tooth movement between the flapped corticotomy group and the corticotomy-only group.Compared with traditional orthodontic tooth movement,both the flapped corticotomygroup and the corticotomy-only group could bring an increase in the expression of RANKL on the pressed periodontal side while there was no significant difference between the two experimental groups.Both the flapped corticot-omy and non-flapped corticotomy could enlarge the area of tissue formation in the periodontal tension zone,and still there was no signif-icant difference between the two surgical methods.Compared with traditional orthodontic tooth movement,both the flapped corticotomy group and the corticotomy-only group could lead to an increase in ALP,OCN and OPN expression on the periodontal tension zone.Conclusion Both flapped corticotomy and corticotomy play a significant role in accelerating orthodontic tooth movement and promoting alveolar bone formation in the early stage.Both surgical methods of PAOO can provide more efficient and stable biological support for orthodontic treatment.

Objective To investigate the effects and molecular mechanisms of ginsenoside Rg1(GSRG1)on the proliferation,mi-gration,and inflammatory cytokine expression of human gingival fibroblasts(HGFs)induced by lipopolysaccharide(LPS).Methods HGFs were isolated and cultured using the tissue block method.The effects of different concentrations of LPS(0,1,5,10,20μg/mL)on inflammatory cytokines in HGFs were detected by ELISA.Cells were divided into three groups:control group(no treat-ment),LPS group(20 μg/mL LPS),and LPS+GSRG1 group(20 μg/mL LPS and 100 mg/L GSRG1).Cell proliferation was detec-ted by cell counting kit-8(CCK-8);cell migration was assessed by Transwell assay;intracellular reactive oxygen species(ROS)lev-els were compared using flow cytometry;and the expression levels of TNF-α,IL-6,NLRP3,p-p38,and p38 proteins were detected by Western blot.Results LPS concentrations of 5,10,and 20 μg/mL significantly increased the expression of IL-6 and TNF-α in HGFs(P＜0.05),with 20 μg/mL showing the strongest pro-inflammatory effect.Compared with the control group,there was no notable difference in the proliferation of HGFs in the LPS group at Day 1 and 2.However,on Day 3,4 and 5,decreased cell proliferation,re-duced migration,significantly increased ROS levels(P＜0.001),elevated protein expression of TNF-α,IL-6,and NLRP3(P＜0.001),and reduced p-p38 protein expression(P＜0.001)were exhibited.Compared with the LPS group,the LPS+GSRG1 group showed significantly enhanced cell proliferation and migration(P＜0.05),reduced ROS levels,decreased protein expression of TNF-α,IL-6,and NLRP3,and increased p-p38 protein expression(P＜0.001).There was no significant change in p38 expression among the three groups.Conclusion GSRG1 can alleviate the inhibitory effects of LPS on the proliferation and migration of HGFs and inhibit the inflammatory response,potentially through mechanisms involving p-p38 protein regulation.

Objective To measure the anatomical parameters of the first maxillary molars in children of different age groups and evaluate the age-related changes in dental crowns.Methods A retrospective analysis was conduc-ted on cone beam computed tomography(CBCT)images of 4-8-year-old children.NNT software was used to ana-lyze multiple important indicators of maxillary first molar.Results A total of 308 first maxillary molars,including 154 pediatric patients,were evaluated in this study.The thickness of the pulp apex H1(left,P=0.01;right,P=0.02)and the thickness of the pulp chamber floor H3(left and right P＜0.01)were positively correlated with age,while the height of the pulp cavity H2(left and right P＜0.01)and the height of the palate tip D1(left P=0.003,right P=0.002)showed a negative correlation with age.There was no significant correlation between the height of the buccal tip and age(P＞0.05).There were significant differences in H1 and H3 between the 4-year-old and 5-year-old age groups between the 8-year-old age group(P＜0.05),as well as significant differences in H2 and D1 between the 4-year-old and 5-year-old between the 6-year-old,7-year-old and 8-year-old age groups(P＜0.05).Conclusion The age-related changes in the crowns of the first maxillary molars are important references for the clinical treatment,and can be accurately measured through CBCT data.

Objective To evaluate and compare the treatment efficacy between concentrated growth factor(CGF)and blood clots(BC)as scaffolds in regenerative endodontic procedures(REPs).Methods Twenty young permanent teeth from 18 healthy children with pulp necrosis or periapical periodontitis were randomly divided into CGF group and BC group.In the CGF group(n=10),after ap-ical bleeding,CGF was inserted into the root canal as a stent.In the BC group(n=10),by stimulating apical bleeding,blood entered the root canal and produced blood clots as scaffolds.Clinical examination and apical X-ray shooting were conducted for each follow-up visit.Cone beam computed tomographic(CBCT)images were acquired preoperatively and at the 24-month recall.The increase of root length,root wall thickness,and newly-formed calcified tissue were calculated.Results The root length increased by(1.68±0.90)mm in the CGF group and(2.36±1.34)mm in the BC group.Root wall thickness increased by(0.44±0.34)mm in the CGF group and(0.50±0.31)mm in the BC group.There was no statistically significant difference in root lengthening and root wall thickening between two groups(P＞0.05).The amount of newly formed calcified tissue in the CGF group((22.13±19.12)mm3)was significantly less than that in the BC group((42.97±22.69)mm3)(P＜0.05).According to the goals for success outlined by American Association of Endodontists(AAE),90%(9/10)of the CGF cases and100%(10/10)of the BC cases achieved the primary and secondary goals(P＞0.05).40%of the CGF cases(4/10)and 60%of the BC cases(6/10)achieved the tertiary goal(P＞0.05).Conclusion CGF is found to be use-ful as a scaffold for REPs,but the success rate is slightly lower than that of BC group and the difference is not statistically significant.

Objective: Investigate osteogenic differentiation of canine periodontal ligament stem cells ( cPDLSCs) via over-expression ephrinB2 in cPDLSCs． Methods : cPDLSCs were isolated from the premolars and molars of Beagle．After transfected with EfnB2-GFP-Bsd and GFP-Bsd empty Vector，cPDLSCs were induced to osteogenic differentiation．Western blot was used to invest the expression of ephrinB2 protein．The effect of osteogenic differentiation of EfnB2-cPDLSCs and Vector-cPDLSCs were analyzed by RT-PCR , CCK-8，Alizarin-red S staining and ALP. Results: There was no significant difference in cell proliferation between EfnB2-cPDLSCs and Vector-cPDLSCs．While EfnB2-cPDLSCs displayed an enhanced ALP activity and more prominent mineralized nodules compared with Vector-cPDLSCs．The odonto-/ osteogenic genes in EfnB2-cPDLSCs were also highly enhanced． Conclusion The results of our study indicated that ephrinB2 gene-transfected cPDLSCs showed enhanced osteogenic differentiation.

Objective: To investigate the effect of Ginsenoside Rg1 (GsRg1) on proliferation , migration and osteogenic differentiation of human gingival fibroblasts (HGFs) and its molecular mechanism. Methods: Human gingival fibroblasts (HGFs) were isolated and cultured by tissue block method , and identified by morphology and immunofluorescence. The effect of six concentrations of GsRg1 (0 , 6. 25 , 12. 5 , 25 , 50 , 100 mg/L) on the proliferation of HGFs was detected by CCK⁃8 method. Transwell assay was used to detect the effects of different concentrations of GsRg1 on the migration ability of HGFs. Alkaline phosphatase (ALP) staining was used to detect osteogenic ability. Alizarin red staining was used to observe and quantify calcium nodules. The expression of COL⁃ Ⅰ , OCN and OPN osteogenic genes was detected by qRT⁃PCR. Western blot was used to detect the protein expression of OCN ,OPN , COL⁃ Ⅰ and PI3K/AKT signaling pathway. Results: Compared with the control group , the proliferation ability of HGFs was significantly improved at the concentrations of 12. 5 ,25 ,50 and 100 mg/L GsRg1 (P < 0. 05) , and the proliferation promotion effect of 100 mg/L GsRg1 was the strongest. There was no significant difference between the 6. 25 mg/L GsRg1 group and the control group. After GsRg1 treatment , the migration ability of HGFs was enhanced and showed concentration dependence. Compared with the control group , the activity of ALP in 100 mg/L GsRg1 group significantly increased (P < 0. 01) . Alizarin red staining showed a significant increase in the number of calcium nodules(P < 0. 01) . The mRNA and egg white expression levels of osteogenic genes OCN , OPN and COL⁃ Ⅰ increased (P < 0. 05 ) . The expression levels of p ⁃PI3K and p ⁃Akt were significantly up⁃regulated with time ( P <0. 05) ,while the expression levels of PI3K and AKT had no significant changes. Conclusion GsRg1 can promote the proliferation and migration of HGFs , and 100 mg/L GsRg1 can promote the osteogenic differentiation of HGFs ,which may be related to the activation of PI3K/AKT signaling pathway.