Introduction The amount and type of maxillary incisor movement during extraction therapy may influence the severity of external apical root resorption (EARR); however, the threshold at which retraction increases the risk remains unclear. This study evaluated the association between incisor retraction magnitude, movement pattern, and EARR in adult patients treated with premolar extraction. Methods A retrospective sample of 180 adults (mean age, 24.73 ± 4.83 years) treated with at least 2 maxillary premolar extractions was divided into 3 groups according to maxillary incisor retraction distance: <4 mm (group 1), 4-8 mm (group 2), and ≥8 mm (group 3). EARR was quantified on panoramic radiographs using the relative root-to-crown ratio and the Malmgren index. Cephalometric variables were used to characterize tooth movement (translation vs tipping) and skeletal change. Multivariable linear regression was performed to identify the predictors of EARR. Results EARR severity demonstrated a progressive increase with greater retraction (group 1 < group 2 < group 3) (P <0.001). Retraction distance, apical displacement, appliance type, and miniscrew anchorage were independent predictors of root-to-crown ratio reduction (P <0.05). In descriptive analyses of movement patterns, greater resorption was observed with translation than with tipping. No significant association was found between skeletal pattern (ANB and MP-SN) and EARR. Conclusions Greater retraction of maxillary incisor is associated with an increased EARR in adult patients with premolar extraction treatment, and translation movement may elevate the risk more than tipping. Retraction magnitude and movement type should be considered when planning treatment aimed at facial profile improvement to minimize iatrogenic root damage. Appliance choice may also influence the risk of root resorption.

INTRODUCTION:Orthodontic tooth movement (OTM) is a mechanically induced inflammatory process. Intriguingly, OTM under periodontitis conditions orchestrates a complex inflammatory microenvironment and exacerbates bone resorption. OBJECTIVES:Stimulator of interferon genes (STING) is a key inflammation mediator, but its role in OTM with periodontitis was unclear. METHODS:We established an OTM model in rats with ligature-induced periodontitis. In vitro, rat periodontal ligament fibroblasts (PDLFs) were subjected to compressive stress and LPS to mimic orthodontic force and periodontitis inflammation. STING was activated with agonists (cGAMP/diABZI) or inhibited with H151 or knockdown. Inflammatory responses and bone resorption were assessed. RNA sequencing and co-IP followed by LC-MS/MS were used to identify downstream signals. RESULTS:STING activation in PDLFs increased IL-1β and IL-6 while reducing Runx-2 and osteogenesis. In periodontitis-OTM rats, STING, IL-1β and IL-6 were upregulated and Runx-2 downregulated on the compression side, leading to increased alveolar bone loss that was rescued by H151. Under mechanical-inflammatory stress, activated STING triggered ER stress, and a cascade of cellular responses including increased pro-inflammatory mediators, enhanced apoptosis, altered mechano-response, and suppressed osteogenesis. Meanwhile, Annexin A2 (Anxa2) was identified as a novel STING interactor. Anxa2 knockdown mirrored STING inhibition, suppressing ER stress, inflammatory activation, apoptosis and mechano-response. Mechanistically, Anxa2 knockdown markedly reduced P65 phosphorylation and nuclear translocation, suggesting Anxa2 may serve as an intermediary linking STING to NF-κB activation. STING-Anxa2 interaction was notably increased in PDLFs and in compression-side periodontal tissues under mechanical-inflammatory stress. CONCLUSIONS:Within an inflammatory milieu, STING activation in PDLFs is associated with ER stress, pro-inflammatory responses, apoptosis, and suppressed osteogenesis that collectively accelerate bone resorption during OTM. We identified Annexin A2 (Anxa2) as a novel STING interactor whose knockdown attenuated these responses and NF-κB activation, suggesting Anxa2 as a functional intermediary in STING-mediated inflammation.

Objectives To evaluate whether digital orthodontic setups can predict the presence and severity of postoperative open gingival embrasures (OGEs) in adult extraction cases treated with fixed appliances. Materials and Methods This retrospective study included 62 adults treated with four-premolar extractions and fixed appliances (620 anterior interproximal sites). Actual OGEs were assessed on post-treatment intraoral photographs. Predicted OGEs were assessed on digital setups generated on a clear aligner platform. Binary performance was evaluated using accuracy, sensitivity, specificity, PPV, NPV, F1 score, and Cohen’s κ. Severity agreement (modified Jemt grades) was assessed using weighted κ, mean absolute error (MAE), and Spearman’s ρ. Analyses were performed overall and by arch, sex, and site. Results Predicted OGE incidence approximated the observed rate (76.5% vs 71.9%; bias +4.5%). Binary prediction showed high performance (accuracy 91.6%, sensitivity 0.916, specificity 0.918, PPV 97.3%, NPV 77.0%, F1 0.943, κ 0.823). Severity prediction showed substantial agreement (weighted κ 0.716–0.774; MAE 0.194; ρ 0.786), with exact matches in 80.8% of sites and ±1-grade agreement in 99.8%. Conclusions Digital setups provide clinically meaningful prediction of postoperative OGEs after fixed-appliance extraction treatment, with modest overprediction. Clinical Relevance Digital setup–based prediction enables early identification of embrasure sites at higher esthetic risk, supporting proactive soft-tissue risk assessment and informed treatment planning in adult extraction orthodontics.

Objective: The objective of this study is to develop a convolutional neural network (CNN) for the automatic detection of soft and hard tissue landmarks and the classification of lip thickness on lateral cephalometric radiographs. Methods: A dataset of 1019 pre-orthodontic lateral cephalograms from patients with diverse malocclusions was utilized. A CNN-based model was trained to automatically detect 22 cephalometric landmarks. Upper and lower lip thicknesses were measured using some of these landmarks, and a pre-trained decision tree model was employed to classify lip thickness into the thin, normal, and thick categories. Results: The mean radial error (MRE) for detecting 22 landmarks was 0.97 ± 0.52 mm. Successful detection rates (SDRs) at threshold distances of 1.00, 1.50, 2.00, 2.50, 3.00, and 4.00 mm were 72.26%, 89.59%, 95.41%, 97.66%, 98.98%, and 99.47%, respectively. For nine soft tissue landmarks, the MRE was 1.08 ± 0.87 mm. Lip thickness classification accuracy was 0.91 ± 0.04 (upper lip) and 0.90 ± 0.04 (lower lip) in females and 0.92 ± 0.03 (upper lip) and 0.88 ± 0.05 (lower lip) in males. The area under the curve (AUC) values for lip thickness were ≥0.97 for all gender-lip combinations. Conclusions: The CNN-based landmark detection model demonstrated high precision, enabling reliable automatic classification of lip thickness using cephalometric radiographs.

Objective To investigate the clinical effect of the Myobrace appliance and traditional functional appliances in treating Class II malocclusions. Methods Six databases (PubMed, Web of Science, Cochrane Library, ClinicalTrials.gov, CNKI, and Embase) were searched to collect and compare articles regarding the effect of the Myobrace appliance and traditional functional appliances for treating Class II malocclusions in children. The literature in both the English and Chinese languages was systematically searched. Randomised controlled trials, non-randomised controlled trials, and retrospective studies were included. A meta-analysis was performed using the RevMan5.4.1 software. Results A total of 12 trials involving 577 patients were included in the quantitative synthesis analysis. The results indicated that, compared to a Twin-block group, the Myobrace group showed significantly smaller reductions in the SNA angle, smaller increases in Ar-Go and Go-Me (mm), and smaller decreases in overbite and overjet (mm) (p < 0.05 for all). Additionally, compared to an Activator group, the Myobrace group demonstrated a significantly smaller increase in the SNB angle (p < 0.05). Conclusions Moderate evidence suggests that the Myobrace appliance and traditional functional appliances were effective in correcting a Class II malocclusion, but the Twin-block appliance was more effective than the Myobrace appliance in inhibiting maxillary growth and reducing overjet and overbite, while the Activator was more effective in promoting mandibular growth.

TMJOA as a progressive degenerative disease of the TMJ, is featured as enhanced inflammation, chondrocyte apoptosis, ECM degradation and subchondral bone remodeling, resulting in local pain and functional impairment that further reduces patients' quality of life. However, its etiology is ambiguous, leading to no consensus regarding the most effective treatment for patients with TMJOA. L-arg is a conditionally essential amino acid that participates in regulating inflammation, ECM orchestration, cellular growth and proliferation, but the role and mechanism of L-arg in TMJOA remain unclear. L-arg exerts different functions in contexts- and tissue microenvironments-dependent manner. For example, excess L-arg induces acute pancreatitis via the JAK2/ STAT3 pathway, the iNOS/NO pathway and the HMGB1/TLR4/NF-kappa B pathway; Arg-II in advanced atherosclerosis impairs endothelial autophagy through regulation of mTOR signaling. Interestingly, these signaling pathways are tightly involved in the reported pathological process of TMJOA. We here unexpectedly found that L-arg is significantly elevated in the plasma of TMD patients using mass spectrometry. Thus, through literature review and analysis, we proposed that the upregulation of L-arg activated iNOS/NO pathway, Arg-II pathway, mTOR pathway and NF-kappa B pathway to prompt TMJOA development. Related pathway inhibitors could be an alternative treatment strategy for TMJOA.

To investigate and compare the facial asymmetry (hard and soft tissues) among skeletal Class I, II, and III patients. A total of 221 subjects, including skeletal Class I (n = 80), skeletal Class II (n = 75), and skeletal Class III (n = 66), were included in the study. CBCT, 22 skeletal landmarks, and 10 soft tissue landmarks were used for the measurements and the asymmetry index was calculated to assess the facial asymmetry. Statistical analyses included one-way ANOVA, Kruskal–Wallis test, and Spearman correlation analysis. The skeletal Class III patients presented greater asymmetry than Class II patients for 10 hard tissue landmarks and 3 soft tissue landmarks (p < 0.05). High correlation of asymmetry was found between four soft tissue landmarks and their corresponding skeletal landmarks (rs ≥ 0.71), as well as Me and ANS (r > 0.86). The ANS and Me in 21.3% patients deviated to contralateral sides. The skeletal Class III patients had more facial asymmetry than the Class II patients. Soft tissues showed similar asymmetry as the underlying hard tissues rather than a compensation of the hard tissue asymmetry. The inconsistency in the deviation of Me and ANS may exacerbate facial asymmetry.

AbstractIntroductionTemporomandibular joint osteoarthritis (TMJ OA) is a major disease that affects maxillofacial health and is characterised by cartilage degeneration and subchondral bone remodelling. Obesity is associated with the exacerbation of pathological manifestations of TMJ OA. However, the underlying mechanism between adipose tissue and the TMJ axis remains limited.ObjectivesTo evaluate the effects of obesity and the adipose tissue on the development of TMJ OA.MethodsThe obesity‐related metabolic changes in TMJ OA patients were detected by physical signs and plasma metabolites. The effects of adipose tissue‐derived EVs (Ad‐EVs) on TMJ OA was investigated through histological and cytological experiments as well as gene editing technology. Alterations of Ad‐EVs in obese state were identified by microRNA‐seq analysis and the mechanism by which EVs affect TMJ OA was explored in vitro and in vivo.ResultsObesity and the related metabolic changes were important influencing factors for TMJ OA. Ad‐EVs from obese mice induced marked chondrocyte apoptosis, cartilage matrix degradation and subchondral bone remodelling, which exacerbated the development of TMJ OA. Depletion of Ad‐EVs secretion by knocking out the geranylgeranyl diphosphate synthase (Ggpps) gene in adipose tissue significantly inhibited the obesity‐induced aggravation of TMJ OA. MiR‐3074‐5p played an important role in this process .ConclusionsOur work unveils an unknown link between obese adipose tissue and TMJ OA. Targeting the Ad‐EVs and the miR‐3074‐5p may represent a promising therapeutic strategy for obesity‐related TMJ OA.Key points High‐fat‐diet‐induced obesity aggravate the progression of TMJ OA in mice. Obese adipose tissue participates in cartilage damage through the altered miRNA in extracellular vesicles. Inhibition of miR‐3074‐5p/SMAD4 pathway in chondrocyte alleviated the effect of HFD‐EVs on TMJ OA.

Objective We explored the comparative effectiveness of available therapies for chronic pain associated with temporomandibular disorders (TMD). DESIGN Systematic review and network meta-analysis of randomised clinical trials (RCTs).DATA SOURcES MEDLINE, EMBASE, CINAHL, CENTRAL, and SCOPUS were searched to May 2021, and again in January 2023.STUDY SELEcTION Interventional RCTs that enrolled patients presenting with chronic pain associated with TMD.DATA EXTRAcTION AND SYNTHESIS Pairs of reviewers independently identified eligible studies, extracted data, and assessed risk of bias. We captured all reported patient-important outcomes, including pain relief, physical functioning, emotional functioning, role functioning, social functioning, sleep quality, and adverse events. We conducted frequentist network meta-analyses to summarise the evidence and used the GRADE approach to rate the certainty of evidence and categorise interventions from most to least beneficial.RESULTS 233 trials proved eligible for review, of which 153-enrolling 8713 participants and exploring 59 interventions or combinations of interventions-were included in network meta-analyses. All subsequent effects refer to comparisons with placebo or sham procedures. Effects on pain for eight interventions were supported by high to moderate certainty evidence. The three therapies probably most effective for pain relief were cognitive behavioural therapy (CBT) augmented with biofeedback or relaxation therapy (risk difference (RD) for achieving the minimally important difference (MID) in pain relief of 1 cm on a 10 cm visual analogue scale: 36% (95% CI 33 to 39)), therapist-assisted jaw mobilisation (RD 36% (95% CI 31 to 40)), and manual trigger point therapy (RD 32% (29 to 34)). Five interventions were less effective, yet more effective than placebo, showing RDs ranging between 23% and 30%: CBT, supervised postural exercise, supervised jaw exercise and stretching, supervised jaw exercise and stretching with manual trigger point therapy, and usual care (such as home exercises, self stretching, reassurance). Moderate certainty evidence showed four interventions probably improved physical functioning: supervised jaw exercise and stretching (RD for achieving the MID of 5 points on the short form-36 physical component summary score: 43% (95% CI 33 to 51)), manipulation (RD 43% (25 to 56)), acupuncture (RD 42% (33 to 50)), and supervised jaw exercise and mobilisation (RD 36% (19 to 51)). The evidence for pain relief or physical functioning among other interventions, and all evidence for adverse events, was low or very low certainty.cONcLUSION When restricted to moderate or high certainty evidence, interventions that promote coping and encourage movement and activity were found to be most effective for reducing chronic TMD pain.REGISTRATION PROSPERO (CRD42021258567)

Background:To investigate the relationship between different skeletal facial types and anterior alveolar bone thickness with cone-beam computed tomography (CBCT) in an Asian population.Methods:A total of 130 patients with 1,560 healthy anterior teeth were enrolled. On three-dimensional reconstructed images, Frankfurt-mandibular plane angle (FMA) value and angle formed by subspinale, nasion, and supramental (ANB) value were measured, and subjects were categorized into different groups based on their vertical skeletal patterns as well as sagittal jaw relationships. For each tooth, the thickness of alveolar bone was measured at three locations: 1, 3, and 5 mm apical to alveolar bone crest. Descriptive statistics were used. Kruskal-Wallis test, one-way ANOVA, and independent-samples t-test were used for further analysis.Results:Men's maxillary anterior teeth's lingual alveolar bone thickness was significantly greater than women's (P<0.05). Strong correlations were found between vertical skeletal patterns and lingual alveolar bone thickness of maxillary/mandibular anterior teeth (R2=0.302, P<0.01 in the maxilla; R2=0.311, P<0.01 in the mandible). However, no significant difference was shown in the alveolar bone thickness among people with different sagittal bone profiles.Conclusions:The lingual alveolar bone of the maxillary anterior teeth is thicker in males than in females. With the increase of FMA, the anterior alveolar bone gradually became thinner.

Oxidative stress is involved in the pathogenesis of various inflammatory diseases, such as periodontitis. When periodontitis occurs, reactive oxygen species (ROS) are overproduced and cannot be balanced by the antioxidant defense system, resulting in tissue damage. Madecassic acid (MA), an abundant triterpenoid in Centella asiatica (L.) Urban, has been used as a wound healing, antiinflammatory, and anticancer agent. Moreover, recent studies have shown that MA has an antioxidative effect, but the underlying mechanism remains unclear. Here, we established an effective oxidative stress model induced by hydrogen peroxide (H2O2) in human periodontal ligament fibroblasts (hPDLFs) to investigate the antioxidant and protective effects of MA against cell damage and its underlying mechanism of action. Pretreatment with MA inhibited cell apoptosis and promoted cell invasion and migration against oxidative injury induced by H2O2. In addition, MA was able to maintain mitochondrial membrane potential (ΔΨm) under oxidative stress. Notably, we found that MA restored redox balance by reducing intracellular ROS production. Furthermore, we investigated apoptosis-related proteins and found that the levels of anti-apoptosis markers Bcl-xL and Bcl-2 were remarkably upregulated, whereas that of the pro-apoptotic marker Bax was strikingly downregulated. Collectively, these findings suggest that MA inhibits H2O2-induced oxidative stress and apoptosis of hPDLFs by reducing intracellular ROS production to maintain ΔΨm stability.

OBJECTIVES To compare preparation time and 1-year Invisalign aligner attachment survival between a flowable composite (FC) and a packable composite (PC). MATERIALS AND METHODS Fifty-five participants (13 men and 42 women, mean age ± SD: 24.2 ± 5.9 years) were included in the study. Ipsilateral quadrants (ie, maxillary and mandibular right, or vice versa) of attachments were randomly assigned to the FC group (Filtek Z350XT Flowable Restorative) and the PC group (Filtek Z350XT Universal Restorative) by tossing a coin. The primary outcome was preparation time. The secondary outcome was time to the first damage of an attachment. Preparation times were compared using the paired t-test, and the survival data were analyzed by the Cox proportional hazards model with a shared frailty term, with α = .05. RESULTS The preparation times were significantly shorter with the FC (6.22 ± 0.22 seconds per attachment) than with the PC (32.83 ± 2.16 seconds per attachment; P < .001). The attachment damage rates were 14.79% for the FC and 9.70% for the PC. According to the Cox models, attachment damage was not significantly affected by the attachment material, sex, arch, tooth location, attachment type, presence of overbite, or occurrence of tooth extraction. CONCLUSIONS The use of a FC may save time as compared with the use of a PC. With regard to attachment survival, there was no significant difference between the two composites. None of the covariates of attachment materials (sex, arch, tooth location, attachment type, presence of overbite, oir occurrence of tooth extraction) affected attachment damage.

目的 系统评价大块复合树脂与分层复合树脂的边缘微渗漏相关性能及临床表现。方法 通过系统评价的方法，比较大块复合树脂与分层复合树脂及不同种类大块复合树脂用于后牙窝洞充填在边缘着色、边缘间隙百分比的差异。结果 大块复合树脂与分层复合树脂及不同种类大块复合树脂用于后牙窝洞充填在边缘着色、边缘间隙百分比的差异无统计学意义。结论 大块复合树脂在边缘微渗漏临床表现方面略优于传统复合树脂，是后牙深龋的理想充填材料。

Background Periodontal tissue regeneration (PTR) is the ultimate goal of periodontal therapy. Currently, stem cell therapy is considered a promising strategy for achieving PTR. However, there is still no conclusive comparison that distinguishes clear hierarchies among different kinds of stem cells. Methods A systematic review and network meta-analysis (NMA) was performed using MEDLINE (via PubMed), EMBASE, and Web of Science up to February 2020. Preclinical studies assessing five types of stem cells for PTR were included; the five types of stem cells included periodontal ligament-derived stem cells (PDLSCs), bone marrow-derived stem cells (BMSCs), adipose tissue-derived stem cells (ADSCs), dental pulp-derived stem cells (DPSCs), and gingival-derived stem cells (GMSCs). The primary outcomes were three histological indicators with continuous variables: newly formed alveolar bone (NB), newly formed cementum (NC), and newly formed periodontal ligament (NPDL). We performed pairwise meta-analyses using a random-effects model and then performed a random-effects NMA using a multivariate meta-analysis model. Results Sixty preclinical studies assessing five different stem cell-based therapies were identified. The NMA showed that in terms of NB, PDLSCs (standardized mean difference 1.87, 95% credible interval 1.24 to 2.51), BMSCs (1.88, 1.17 to 2.59), and DPSCs (1.69, 0.64 to 2.75) were statistically more efficacious than cell carriers (CCs). In addition, PDLSCs were superior to GMSCs (1.49, 0.04 to 2.94). For NC, PDLSCs (2.18, 1.48 to 2.87), BMSCs (2.11, 1.28 to 2.94), and ADSCs (1.55, 0.18 to 2.91) were superior to CCs. For NPDL, PDLSCs (1.69, 0.92 to 2.47) and BMSCs (1.41, 0.56 to 2.26) were more efficacious than CCs, and PDLSCs (1.26, 0.11 to 2.42) were superior to GMSCs. The results of treatment hierarchies also demonstrated that the two highest-ranked interventions were PDLSCs and BMSCs. Conclusion PDLSCs and BMSCs were the most effective and well-documented stem cells for PTR among the five kinds of stem cells evaluated in this study, and there was no statistical significance between them. To translate the stem cell therapies for PTR successfully in the clinic, future studies should utilize robust experimental designs and reports.

OBJECTIVE:The objective of this review was to evaluate the effect of subgingival debridement by ultrasonic debridement (UD) in comparison with subgingival air polishing (SubGAP) during periodontal maintenance. METHODS:A systematic search of electronic databases was conducted to identify publications from January 01, 2000, to December 21, 2018. Publication selection, data extraction, and risk of bias assessment were performed by two reviewers independently. The addressed problem-intervention-comparison-outcomes question was "For patients in the periodontal maintenance phase, is SubGAP more likely to result in better clinical outcomes than UD?" RESULTS:From a total of 435 articles identified, 6 studies were included. Although none of them was evaluated to have a low risk of bias, overall, the main reason was that blinding of personnel was almost impossible to achieve for the study design. Owing to the heterogeneity, the data from included studies could not be synthesized. Most of the included studies suggested no statistical difference in pocket-depth reduction, except for one which showed UD was superior to SubGAP. In terms of clinical attachment loss and gingival regression, no treatment was indicated to have more benefits than the other based on the present evidence. SubGAP had a preferable comfort level compared with UD, as reported. It must be noted that none of included studies' follow-up time was more than 1 year. CONCLUSION:The clinical efficacy of SubGAP compared with that of UD for periodontal maintenance remains inconclusive on account of limited evidence. To date, neither SubGAP nor UD showed superior clinical effect when compared. High-quality, well-designed clinical studies are still needed to ascertain the long-term clinical stability.

目的:探讨Spee曲线和拥挤度对口腔正畸模型2D和3D测量法的影响.方法:收集临床就诊中34例恒牙列期患者的记存模型,进行2D(模型法和影印法)和3D(数字化模型)的测量,对牙齿大小,牙弓长度和宽度,拥挤度以及Spee曲线深度测量,随后按Spee曲线深度和拥挤程度分组比较,并进行单因素方差分析的统计学分析,如有差异再行LSD法的两两比较分析.结果:Spee曲线和拥挤度对牙体大小的测量有明显统计学差异(P＜0.05).两两比较结果表明,数字模型和影印模型的差异较大,上颌轻度拥挤组为(1.16±1.34) mm(P=0.000),下颌轻度拥挤组为(1.14±1.40) mm(P=0.000),下颌中度拥挤组为(1.35±2.19)mm(P=0.028).随着Spee曲线曲线深度的增加,石膏模型和数字模型与影印模型对比,牙齿的大小有明显的变化,且有统计学差异.数字模型与影印模型在Spee曲线中度组的差异为(1.70±1.39)mm(P=0.001),Spee曲线深度组为(1.66±1.46) mm(P=0.002).结论:轻/中度拥挤组,2D和3D测量差异较大;Spee曲线深度对2D影印模型的测量有较大影响.

Background. Clear aligners have become increasingly popular because of their esthetics and comfort. The authors' aim in this systematic review was to compare periodontal health in patients undergoing orthodontic treatment with clear aligners with that of those undergoing orthodontic treatment with fixed appliances. Types of Studies Reviewed. The authors systematically searched the PubMed, Web of Science, Cochrane Library, and Embase databases to collect related studies. After extracting data and assessing quality, the authors performed a meta-analysis and trial sequential analysis. The authors used the Grading of Recommendations Assessment, Development and Evaluation system to assess the quality of the evidence. Results. The authors included 9 studies in the quantitative synthesis analysis. Clear aligners were better for periodontal health, including plaque index (mean difference [MD], -0.53; 95% confidence interval [CI], -0.85 to -0.20; P = .001), gingival index (MD, -0.27; 95% CI, -0.37 to -0.17; P < .001), and probing depth (MD, -0.35; 95% CI, -0.67 to -0.03; P = .03), than were fixed appliances. However, the trial sequential analysis outcome indicated a false-positive meta-analysis result for probing depth. The authors downgraded the level of the evidence because of the risk of bias and inconsistency. Conclusions and Practical Implications. Clear aligners were better for periodontal health than fixed appliances and might be recommended for patients at high risk of developing gingivitis. However, high-quality studies still are required.

Clear aligners have become increasingly popular because of their esthetics and comfort. The authors' aim in this systematic review was to compare periodontal health in patients undergoing orthodontic treatment with clear aligners with that of those undergoing orthodontic treatment with fixed appliances.The authors systematically searched the PubMed, Web of Science, Cochrane Library, and Embase databases to collect related studies. After extracting data and assessing quality, the authors performed a meta-analysis and trial sequential analysis. The authors used the Grading of Recommendations Assessment, Development and Evaluation system to assess the quality of the evidence.The authors included 9 studies in the quantitative synthesis analysis. Clear aligners were better for periodontal health, including plaque index (mean difference [MD], -0.53; 95% confidence interval [CI], -0.85 to -0.20; P = .001), gingival index (MD, -0.27; 95% CI, -0.37 to -0.17; P < .001), and probing depth (MD, -0.35; 95% CI, -0.67 to -0.03; P = .03), than were fixed appliances. However, the trial sequential analysis outcome indicated a false-positive meta-analysis result for probing depth. The authors downgraded the level of the evidence because of the risk of bias and inconsistency.Clear aligners were better for periodontal health than fixed appliances and might be recommended for patients at high risk of developing gingivitis. However, high-quality studies still are required.

Background. Few researchers have investigated the relationship between supernumerary teeth (ST) and impacted incisors. The authors investigated the relationship between ST and impacted incisors in the maxillary anterior area in the mixed dentition.Methods. Using cone-beam computed tomography, the authors diagnosed 417 ST among 294 patients (age range, 6-12 years; 220 boys and 74 girls). The number, morphology, growth orientation, and position of ST were recorded along with the presence of impacted incisors.Results. The authors reported that 23.1% of patients having ST (n = 68; mean [standard deviation] age 8.5 [1.6] years) also had impacted incisors. Morphology (molariform and odontomelike), growth orientation (normal and no orientation), and position (coronal) of the ST were significantly associated with impacted incisors (P < .05 for all). An increase of 1 year in age was associated with a decreased risk of having ST accompanied by impacted incisors (odds ratio, 0.76; 95% confidence interval, 0.63 to 0.92). An increase of 1 ST more than doubled the risk of having an impacted incisor (odds ratio, 2.39; 95% confidence interval, 1.44 to 3.96).Conclusions. In this population, the number, morphology, growth orientation, and position of ST as well as the patient's age were associated with impacted incisors in the maxillary anterior area during the mixed dentition.

Reactive oxygen species (ROS) is a pivotal pathogenic factor in the development of osteoporosis. Dalbergioidin (DAL) can be isolated from Uraria crinite, an edible herb used as a natural food for childhood skeletal dysplasia. Recent research has implicated DAL as having an antiosteoporosis effect, although the mechanism of this is unclear. We used an effective oxidative stress model, induced by hydrogen peroxide (H2O2) in osteoblastic MC3T3-E1 cells, to investigate the protective effects of DAL in osteoporosis and the underlying molecular mechanisms. The results indicated that treatment with DAL maintained redox balance, reduced MC3T3-E1 cell apoptosis, improved alkaline phosphatase activity, and elevated the osteogenic-related protein expression of Runx2, Osterix, and BMP2 against oxidative damage induced by H2O2. The potential molecular mechanism involved in the protective effect of DAL against H2O2-induced cell death in MC3T3-E1 cells may lie in the activation of the PI3K/AKT/SMAD1 cell signal pathway. Taken together, the results indicated that the potential protective effects of DAL against osteoporosis were linked to a reduction in oxidative damage, suggesting that DAL may be useful in bone metabolism diseases, particularly osteoporosis.