Introduction: This article reports a two-phase treatment case for skeletal Class II mandibular retrognathism adolescent patient using a Twin-Block appliance followed with fixed appliance treatment. The results demonstrates that the Twin-Block appliance can effectively promote mandibular growth in adolescent patients while improving facial profile and inducing adaptive remodeling of the temporomandibular joint. Additionally, it enhances respiratory function and contributes to the improvement of cervical posture. Case description: The patient was initially examined at 10y5m, with a chief complaint of protruding upper teeth and a retruded chin. Cephalometric analysis indicated sagittal skeletal discrepancy with mandibular retrognathism, proclined upper incisors, and upright lower incisors. A two-phase treatment plan was formulated: Phase I: A Twin-Block appliance with maxillary expansion was performed. Phase II: Fixed appliances were employed. After the two-phase treatment, significant improvements were achieved: effective retraction of the upper incisors, correction of the overjet, and enhanced nasolabial-mental curve. Post-treatment imaging demonstrated increased condylar length, width, and height, along with glenoid fossa remodeling and anterior condylar displacement. Additionally, cervical spine alignment and head-neck posture improved, with correction of the preoperative cervical postural deviation Discussion: Maxillary expansion with the Twin-Block appliance corrects transverse maxillomandibular discrepancy and facilitates mandibular growth development. Thus guides the mandible forward, thereby increasing the upper airway volume and improving respiratory function. Concurrently, it enhances cervical posture alignment by reducing head-neck postural deviation. Conclusion/clinical significance: The Twin-Block appliance demonstrates significant therapeutic efficacy in adolescent patients with skeletal Class II malocclusion characterized by mandibular retrognathism.

The commonly used lateral cephalometric radiographs, including traditional lateral cephalometric radiographs and CBCT-synthesized lateral cephalometric radiographs, have the problem of overlapping anatomical structures, which interferes with the identification of landmarks. Therefore, we proposed a new method called CBCT-based locally reconstructed lateral cephalometric radiographs and evaluated its precision and reproducibility. CBCT and lateral cephalometric radiographs were obtained from five orthodontic patients. Twenty-six cephalometric landmarks were identified using three methods by ten orthodontists. The landmarks on each image were recorded as (X, Y), and the absolute values of the differences between each measurement and the average values of the X and Y coordinates were calculated (ΔX and ΔY). Additionally, the distance between each located point and the centroid was calculated (ΔD). The differences in ΔX, ΔY, and ΔD among the groups were compared through analysis of variance (ANOVA). Bonferroni post hoc correction was used for pairwise comparisons. p < 0.05 was considered statistically significant. The reproducibility of 14 landmarks in the CBCT-based locally reconstructed lateral cephalometric radiographs was better than that of the other methods in at least one direction (p < 0.05). Among these landmarks, the precision of the CBCT local reconstruction group was greater in all directions for five landmarks than that of the other two groups (p < 0.05). The CBCT locally reconstructed lateral cephalometric radiographs proposed in this study enhanced the precision and reproducibility of cephalometric landmark identification.

The age-related functional decline of bone marrow mesenchymal stem cells significantly impairs bone regeneration capacity. Exosomes derived from umbilical cord mesenchymal stem cells (UCMSCs) have emerged as promising therapeutic agents in regenerative medicine and anti-aging research due to their bioactive cargo and low immunogenicity. This study investigated the rejuvenating potential of UCMSCs-derived exosomes (UCMSC-Exos) on senescent jaw bone marrow mesenchymal stem cells (JBMMSCs) and their ability to enhance bone repair in aged rats. Senescent JBMMSCs were treated with UCMSC-Exos, and their effects on cellular senescence, proliferation, migration, and osteogenic capability were assessed using senescence-associated beta-galactosidase (SA-β-gal) staining, CCK8 assays, scratch assays, alizarin red S staining, alkaline phosphatase staining, RT-qPCR, ELISA and western blotting. The underlying mechanisms were explored through western blot analysis of autophagy markers and PI3K/AKT/mTOR pathway. For in vivo evaluation, calvarial defect models were established in aged rats, and the bone repair efficacy of UCMSC-Exos was assessed by micro-CT, histological staining, immunohistochemical staining for OCN and ALP, and immunofluorescence staining for OPN and OSX. UCMSC-Exos treatment markedly attenuated cellular senescence in JBMMSCs, as demonstrated by decreased SA-β-gal-positive cells and downregulation of key senescence-associated proteins (p53, p21, and p16) and pro-inflammatory cytokines (IL-6 and TNF-α). The exosome-treated cells showed significant improvements in proliferative capacity, migratory ability, and osteogenic differentiation potential compared to untreated controls. Mechanistically, UCMSC-Exos restored autophagy through modulation of the PI3K/AKT/mTOR signaling pathway, as demonstrated by altered protein expression. In rat calvarial defect models, UCMSC-Exos treatment resulted in better bone repair in aged rats. This study demonstrated that UCMSC-Exos could rejuvenate senescent JBMMSCs by activating autophagy via the regulation of PI3K/AKT/mTOR pathway, and enhance bone repair in aged rats. UCMSC-Exos hold potential as a cell-free therapeutic tool for anti-aging treatments and regenerative medicine, particularly for age-related skeletal disorders.

BackgroundCircular RNAs participate in the development of periodontitis. The present work aims to reveal the role and mechanism of circ_0087199 in human periodontal ligament cell (PDLC) injury during periodontitis.MethodsPDLCs were treated with lipopolysaccharides (LPS) to establish a periodontitis cell model. Quantitative real-time polymerase chain reaction was used to detect the expression of circ_0087199, miR-527, toll-like receptor 4 (TLR4). Western blot analysis assay was performed to assess protein expression. Cell viability, proliferation, apoptosis and inflammation were investigated by cell counting kit-8, EdU assay, flow cytometry and enzyme-linked immunosorbent assay, respectively. Oxidative stress was evaluated by malondialdehyde assay kit and superoxide dismutase activity assay kit. The interaction between miR-527 and circ_0087199 or TLR4 was confirmed by a dual-luciferase reporter assay.ResultsCirc_0087199 and TLR4 expression levels were significantly increased, while miR-527 was decreased in the periodontal ligament tissues of periodontitis patients and LPS-stimulated PDLCs when compared with controls. LPS treatment inhibited cell viability and proliferation but induced cell apoptosis, inflammation and oxidative stress, whereas these effects were attenuated after circ_0087199 knockdown. Circ_0087199 bound to miR-527 and regulated LPS-caused PDLC damage by targeting miR-527. Additionally, the overexpression of TLR4, a target gene of miR-527, rescued miR-527 mimic-mediated effects on LPS-treated PDLCs. Further, the regulation of circ_0087199 toward TLR4 involved miR-527.ConclusionCirc_0087199 knockdown attenuated LPS-induced apoptosis, inflammation and oxidative stress of PDLCs by regulating the miR-527/TLR4 pathway. circ_0087199 knockdown attenuated lipopolysaccharides-induced apoptosis, inflammation and oxidative stress of periodontal ligament cells by regulating the miR-527/toll-like receptor 4 pathway However, comprehensive roles of circ_0087199 in the pathophysiological processes of periodontitis should be analyzed because one circular RNAs usually has many target microRNAs. Additionally, in vivo data are lacking, and further investigation needs to be performed to provide in vivo evidence of circ_0087199 regulating periodontitis progression. Nevertheless, this work provides a theoretical basis for further drug administration of periodontitis. image

Management of dilaceration teeth poses a unique challenge to the clinician due to its position within the esthetic zone. This case report describes the management of impacted maxillary central incisor with severe root dilacerations. Surgical exploration was done and orthodontic treatment was planned. The dilacerated incisor was alighed, optimal treatment outcome with esthetic and functional was well done.

Crown-root fracture is a rare type of dental traumatic injury. Management of traumatized teeth sometimes requires a multidisciplinary approach to obtain better esthetic results as well as for the conservation of tooth structure. This article describes the management of a case of oblique crown root fracture of anterior teeth. After the removal of the coronal fragment, the roots were filled with calcium hydroxide. Orthodontic extrusion was initiated for 4 months, and 3 mm extrusion was achieved. The ceramic crown was cemented on anterior fracture teeth. The periodontal condition appeared to be healthy and good esthetic was maintained during the follow-up appointment.

Background/purpose: Idiopathic osteosclerosis (IO) is an intraosseous lesion of asymptomatic, non-expansive, radiopaque. The study aimed to investigate the prevalence and morphometric parameters of IO in orthodontic patients and variations in longitudinal observations and to assess the relationship between IO and orthodontic treatment. Materials and methods: Five hundred and seventy-one orthodontically-treated patients were reviewed. A cross-sectional study was performed with the evaluated parameters, including the age and sex of patients, as well as the number, shape, location and morphometric data of IO observed in panoramic radiography. Long-term behaviour of IO and orthodontic tooth movement were also observed. Also, a control group was set up for comparisons. Results: Sixty-eight (11.3%) patients had 78 lesions all in the mandible with premolar/molar preference and no sex predilection. Lesions were located more commonly at apical and separate sites related to teeth. A large majority of lesions enlarged in the 10-19 years old group, while most lesions had no change in the 30-39 years old group. Hindrances of tooth movement and external root resorption around IO were not found in affected patients. Conclusion: IO is labile lesion that may develop in early stages of life, with little change occurring once the affected individual is mature and being relatively stable in the middle stage of life. Our study supports the hypothesis that IO may be developmental anatomic variations of normal bone. However, no obvious association between IO and orthodontic treatment was found in patients, which may be due to the limitations of two-dimensional shooting of panoramic radiography and the sample size. (c) 2021 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons. org/licenses/by-nc-nd/4.0/).

This study investigated the probable mechanisms of endoplasmic reticulum (ER) stress involved in periodontitis in vitro and in vivo. We isolated periodontal ligament stem cells from periodontitis patients and healthy controls (P-PDLSCs and H-PDLSCs). To further simulate the periodontal microenvironment in patients, lipopolysaccharide (LPS) was used to treat H-PDLSCs. The results showed that periodontitis-related inflammation gave rise to the upregulated expression levels of ER stress representative genes including GRP78, PERK, ATF4, and CHOP. In contrast, the treatment of 4-phenyl butyric acid (4-PBA) remarkably suppressed ER stress and supported cell viability. The increased secretion of proinflammatory factors like TNF-α, IL-1β, and IL-6 and the activation of NF-κB pathway were also attenuated by 4-PBA treatment. Moreover, 4-PBA treatment restored the impaired osteogenic differentiation ability of PDLSCs, as demonstrated by the upregulated expression levels of Runx2 and OCN as well as the enhanced Alizarin red staining. Local administration of 4-PBA could rescue alveolar bone resorption of LPS-induced periodontitis rats. Thus, our findings suggested ER stress might act as a promising therapeutic target against periodontitis.

There is a contradiction between the increasing medical English learning and the traditional teaching system. PDCA theory was evaluated to improve the professional English teaching for Postgraduates. We found that PDCA theory combined the concept of continuous improvement and innovation with the teaching process. It not only improves the teaching level of medical English teachers, but also enables students to have the ability of active learning. It is suggested that PDCA theory could be popularized and applied in professional English Teaching for stomatological postgraduates.

Bone morphogenetic proteins (BMPs), have been shown to enhance the osteogenic differentiation of mesenchymal cells (MCs) and to promote bone formation. BMP6 is known to play an important role in the process of MCs towards osteogenic differentiation by virtue of their osteoinductive and cell type specific proliferative activity. However, the molecular mechanism relate to BMP6 osteoinductive activity is still unclear and continues to warrant further investigation. Msx2 is a member of the homeobox gene family of transcription factors and promotes calcification. Hence, we wondered if it might also play a role in BMP6-induced osteogenesis. In this study, two mouse mesenchymal cell lines were treated with BMP6, adenovirus-Msx2 (Ad-Msx2) or adenovirus-siMsx2 (Ad-siMsx2). Based on the results of mRNA and protein expression, it was indicated that BMP6 could enhance the expression of Msx2 and activate the phosphorylation of Smad 1/5/8, p38 and ERK1/2. Being transfected by Ad-Msx2, the BMP6-induced activation of phosphorylation was significantly promoted. On the contrary, two cell lines transfected by Ad-siMsx2 presented an inhibited expression of three phosphorylated proteins even after being induced by BMP6. The evaluation of ALP, OPN, OC and calcium deposits revealed the osteogenic results those were corresponding to the results of mRNA and protein. Taken together, these findings can be a novel viewpoint for the understanding of the mechanisms of BMP6-induced osteogenesis and provide therapeutic targets of bone defect.

目前,以胜任力为导向的人才培养方式已经广泛深入到全球各个行业,结合当前我国口腔正畸研究生的培养模式,依据口腔临床错牙合畸形患者的诊治特点,初步提出以胜任力为导向的口腔正畸学研究生人才培养模式,为口腔医学生的培养提供崭新的视角.

目的:探讨组蛋白乙酰化酶(histone acetyltransferases,HATs)在人牙周膜干细胞(periodontal ligament stem cells,PDLSCs)中表达以及与内质网应激(endoplasmic reticulum stress,ERs)激活的关系.方法:实时定量PCR筛选HATs在炎症来源牙周膜干细胞(periodontitis periodontal ligament stem cells,P-PDLSCs)中表达情况;使用小干扰RNA(small interfering RNA,siRNA)将筛选出的4个HATs分别抑制,实时定量PCR检测抑制效率和未折叠蛋白反应(unfolded protein response,UPR)相关因子蛋白激酶受体样内质网激酶(protein kinase receptor like ER kinase,PERK)、肌醇需要酶1(inositol requiring enzyme1,IRE1)和转录激活因子6(activating transcription factor 6,ATF6)的表达;透射电镜观察使用小干扰RNA干扰KAT6B(siKAT6B)后内质网形态的变化.结果:与对照组H-PDLSCs相比,4个HATs KAT2A、KAT3B、KAT6A和KAT6B在P-PDLSCs中表达显著降低(分别为0.60±0.21、0.60±0.21、0.42±0.26、0.33±0.28),成功检测到四个HATs沉默效率(分别为0.48±0.18、0.37±0.12、0.12±0.23、0.54±0.10)后,发现siKAT6B后PERK表达升高(1.63±0.21).相比对照组,透射电镜下观察siKAT6B后内质网异常扩张和肿胀.结论:牙周炎症微环境可以引起组蛋白乙酰化酶KAT6B降低,同时引起UPR相关PERK分子激活.

目的 分析健康宣教在正畸治疗中的应用价值.方法 选择2016年9月～2018年9月来我院接受牙齿正畸治疗的患者320例为研究对象.现按照就诊次序,将其随机平均分为对照、观察2组,每组各160例.观察组受试者接受分阶段健康宣教,对照组接受常规宣教,分析结果 .结果相较于对照组,观察组受试者治疗依从性良好者、口腔卫生情况优秀者、未复发者以及治疗满意者人数明显更多,P<0.05.结论 对于接受口腔正畸治疗的患者来讲,同时为其开展分级段口腔健康宣教,有助于提升其正畸依从性,保持口腔卫生,减少疾病复发,提升治疗满意度,因此值得推广.

破骨细胞是一种多核髓系细胞,由血液中循环的骨髓系前体细胞发生细胞质融合而形成.这些破骨前体细胞在受到破骨相关信号因子作用后聚集在骨表面,这些因子包括核因子κB受体活化因子配体(receptor activator of NF-κB ligand,RANKL),它是一种多功能细胞因子,与破骨细胞形成密切相关,广泛表达于骨和骨髓内的细胞中,包括嵌在钙化骨基质中的骨细胞、骨髓基质细胞、B淋巴细胞、T淋巴细胞等.骨组织改建持续存在于生长发育中的骨骼及成年人骨骼中,对机械性等刺激能够做出反应,并且能够清除损伤的、失去活力的骨组织微观病灶,这些微观病灶会随着破骨细胞形成的增多而增加.核因子κB受体活化因子(receptor activator of NF-κB,RANK)是RANKL的受体,二者发生结合可以激活破骨细胞、破骨前体细胞内的核因子kappa B(nuclear factor-kappa B,NF-κB)信号通路,继而贴附于骨表面的破骨细胞及破骨前体细胞,并在其胞膜特定褶皱端分泌氢离子、氯离子和胶原酶,在细胞膜褶皱端下形成盐酸并分泌组织蛋白酶K,分别发挥溶解骨组织矿物质和降解基质作用.破骨细胞沿骨表面移动,并且不断聚集以扩大吸收陷窝,直至骨吸收完成.然而,NF-κB信号通路在破骨细胞形成过程中具有双重调控作用,它既能促进破骨细胞的形成与活化,也能通过RANKL等细胞因子来抑制破骨细胞的形成[1].

目的 调查固定矫治患者治疗前后口腔卫生行为的改变,及矫治中菌斑指数(PLI)、牙龈指数(GI)和龈沟出血指数(SBI)的分布及变化.方法 选取在中国人民解放军总医院口腔正畸科接受治疗的患者323例(男146例,女177例).所有入组患者填写"固定矫治患者口腔卫生行为问卷调查表",并在粘接固定矫治器前及复诊中,记录PLI、GI、SBI指数.结果 经过口腔卫生宣教,患者口腔卫生习惯、饮食习惯以及口腔自检状况均有显著改善.自锁矫治器患者的菌斑指数低于非自锁矫治器患者,差异有统计学意义(P<0.05),女性患者的菌斑指数与牙龈指数均低于男性患者,差异有统计学意义(P<0.05),治疗中每两个月进行口腔牙周状况的检查,PLI、GI、SBI指数平不高于固定矫治器粘接前.拔牙或非拔牙、陶瓷或金属矫治器的选择对于PLI、GI、SBI值的影响没有统计学差异,差异无统计学意义(P>0.05).结论 正畸医师要严格控制菌斑形成,做好口腔卫生宣教与口腔健康监控,有效维持矫治中口腔内环境的健康与稳定.

Physiological root resorption of deciduous teeth is a normal phenomenon, however, the potential mechanisms underlying this process remain unclear. This study aimed to investigate ability of stem cells from human exfoliated deciduous teeth (SHED) on promoting the osteoclastic differentiation of osteoclast precursors and clarify mechanisms underlying this process in vitro. SHED and dental pulp stem cells (DPSCs) were obtained from deciduous teeth and healthy permanent teeth. An indirect co-culture system of SHED or DPSCs were used. The osteoclast precursor peripheral blood mononuclear cells (PBMCs) were established. Ability of SHED and DPSCs in promoting osteoclastogenesis was determined using triiodothyronine receptor auxiliary protein (TRAP) staining, real-time real-time PCR (RT-PCR) and western blotting. The effect of inflammation on the pro-osteoclastogenesis ability of SHED was determined using enzyme linked immunosorbent assay (ELISA), RT-PCR and western blotting. The function of the nuclear factor-κB (NF-κB) pathway in promoting the osteoclastogenesis ability of SHED was determined using RT-PCR and western blotting. SHED exhibited an increased ability to promote osteoclastic differentiation. Expression of tumor necrosis factor-α (TNF-α) was significantly higher in SHED than in DPSCs. Expression of cathepsin K (CTSK), TRAP, and receptor-activator of nuclear-factor-κ B ligand (RANKL), RANKL/osteoprotegerin (OPG) ratio, and expression of cytoplasmic phosphorylated inhibitor of NF-κB α (p-IκBα) and nuclear p65 were markedly up-regulated in SHED post the TNF-α treatment but decreased following NF-κB inhibition. In conclusion, inflammatory cytokine TNF-α appeared to activate NF-κB pathway to up-regulate expression of NF-κB, enhancing ability of SHED in promoting osteoclastogenesis via regulating RANKL/OPG expression.

Objective: To investigate whether Asperosaponin VI improves the inflammatory microenvironment through the PERK pathway to promote osteogenic differentiation of periodontal ligament stem cells. Methods: Human periodontal ligament stem cells (PDLSCs) were isolated and were divided into control group and TNF-alpha group. The ER stress induced by TNF-alpha at a concentration of 10 ng/mL was analyzed. Subsequently, PDLSCs were divided into TNF-alpha group, TNF-alpha plus 4-phenylbutyric acid (PBA) group and TNF-alpha plus Asperosaponin VI group. After expression of PERK siRNA by lentiviral infection, the osteogenic differentiation of PDLSCs after blocking PERK was observed. Effects of saponins VI and 4-PBA on the expression of PDLSC osteogenic genes and PERK pathway molecules in inflammatory microenvironment were analyzed by quantitative PCR and western blotting. Results: After treatment with TNF-alpha at 10 ng/mL, the mRNA expression of Runx2, ALP and OCN in PDLSCs was decreased, but the mRNA and protein expression of GRP78, PERK, ATF4 and CHOP were significantly increased. Furthermore, after the co-culture with saponin VI at 10 mu mol/L, the abundance of ALP-positive cells and the expression of ALP mRNA were significantly improved, and the mRNA and protein levels of Runx2 and OCN were also increased. Conclusion: Asperosaponin VI may restore the osteogenic differentiation ability of PDLSCs by inhibiting the activation of the PERK pathway in inflammatory conditions.

目的:探讨炎症微环境对牙周膜干细胞(PDLSCs)氧化应激和线粒体生成的影响.方法:体外分离因正畸治疗需要而拔除的健康牙齿及慢性牙周炎患牙的PDLSCs,分组培养健康PDLSCs(H-PDLSCs)、炎症PDLSCs(P-PDLSCs)和肿瘤坏死因子α作用下的PDLSCs(T-PDLSCs).培养7d后,采用荧光探针和流式细胞技术检测线粒体及全细胞的活性氧簇(ROS)水平,采用实时定量PCR和Western blot技术分别检测线粒体生成及抗氧化相关基因的mRNA和蛋白表达水平.结果:与H-PDLSCs相比,P-PDLSCs和T-PDLSCs组细胞线粒体和全细胞ROS水平显著增加,线粒体生成相关基因ERRα、PGC-1α、TIMM13、MFN2和抗氧化基因PRDX3与SOD2的mRNA表达水平均显著降低,ERRα、PGC-1α、PGC-1β和SOD2蛋白表达水平均显著降低.结论:炎症微环境显著提高PDLSCs的氧化应激水平,抑制PDLSCs的线粒体生成和抗氧化反应.

Inflammation is a common feature of both peripheral arterial disease (PAD) and periodontitis. Some studies have evaluated the association between PAD and periodontitis. However, there is still no specialized meta-analysis that has quantitatively assessed the strength of the association. Thus, we conducted this meta-analysis to critically assess the strength of the association between PAD and periodontitis.

PURPOSETo investigate the effect of tumor necrosis factor-α (TNF-α) on the ability of stem cells from human exfoliated deciduous teeth (SHED) to promote osteoclastogenesis.METHODSSHED were obtained from deciduous teeth and isolated, purified, cultured in vitro. An indirect co-culture system of SHED and osteoclast precursor peripheral blood mononuclear cells (PBMCs) was established. The expression of osteoclastic gene from PBMCs and NF-κB from SHED were determined after treatment with TNF-α (0, 5, 10, 50, 100 ng/mL) by real-time RT-PCR and Western blot. SPSS 19.0 software package was used for statistical analysis.RESULTSUnder the stimulation of 10ng/mL TNF-α, the expression of CTSK and TRAP was markedly upregulated in PBMCs. Meanwhile, the results of Western blot and real-time RT-PCR showed that the expression of cytoplasmic phosphorylated inhibitor of NF-κB α (p-IκBα) and nuclear p65 in SHED were significantly higher than that without TNF-α stimulation after 10 ng/mL TNF-α treatment.CONCLUSIONSTNF-α regulates the ability of SHED to promote osteoclastogenesis through NF-κB signal pathways.