Clear aligner treatment is a novel technique in current orthodontic practice. Distinct from traditional fixed orthodontic appliances, clear aligners have different material features and biomechanical characteristics and treatment efficiencies, presenting new clinical challenges. Therefore, a comprehensive and systematic description of the key clinical aspects of clear aligner treatment is essential to enhance treatment efficacy and facilitate the advancement and wide adoption of this new technique. This expert consensus discusses case selection and grading of treatment difficulty, principle of clear aligner therapy, clinical procedures and potential complications, which are crucial to the clinical success of clear aligner treatment.
Humans ; Consensus ; Orthodontic Appliance Design ; Orthodontic Appliances, Removable ; Tooth Movement Techniques/methods* ; Malocclusion/therapy* ; Orthodontics, Corrective/instrumentation*

The periodontal ligament (PDL) plays a crucial role in transmitting and dispersing occlusal force, acting as mechanoreceptor for muscle activity during chewing, as well as mediating orthodontic tooth movement. It transforms mechanical stimuli into biological signals, influencing alveolar bone remodeling. Recent research has delved deeper into the biological and mechanical aspects of PDL, emphasizing the importance of understanding its structure and mechanical properties comprehensively. This review focuses on the latest findings concerning both macro- and micro- structural aspects of the PDL, highlighting its mechanical characteristics and factors that influence them. Moreover, it explores the mechanotransduction mechanisms of PDL cells under mechanical forces. Structure-mechanics-mechanotransduction interplay in PDL has been integrated ultimately. By providing an up-to-date overview of our understanding on PDL at various scales, this study lays the foundation for further exploration into PDL-related biomechanics and mechanobiology.
Periodontal Ligament/cytology* ; Humans ; Biomechanical Phenomena ; Mechanotransduction, Cellular/physiology* ; Stress, Mechanical

Patients with periodontal disease often require combined periodontal-orthodontic interventions to restore periodontal health, function, and aesthetics, ensuring both patient satisfaction and long-term stability. Managing these patients involving orthodontic tooth movement can be particularly challenging due to compromised periodontal soft and hard tissues, especially in severe cases. Therefore, close collaboration between orthodontists and periodontists for comprehensive diagnosis and sequential treatment, along with diligent patient compliance throughout the entire process, is crucial for achieving favorable treatment outcomes. Moreover, long-term orthodontic retention and periodontal follow-up are essential to sustain treatment success. This expert consensus, informed by the latest clinical research and practical experience, addresses clinical considerations for orthodontic treatment of periodontal patients, delineating indications, objectives, procedures, and principles with the aim of providing clear and practical guidance for clinical practitioners.
Humans ; Consensus ; Orthodontics, Corrective/standards* ; Periodontal Diseases/complications* ; Tooth Movement Techniques/methods* ; Practice Guidelines as Topic

Insufficient alveolar bone thickness increases the risk of periodontal dehiscence and fenestration, especially in orthodontic tooth movement. Abaloparatide (ABL), a synthetic analog of human PTHrP (1-34) and a clinical medication for treating osteoporosis, has recently demonstrated its potential in enhancing craniofacial bone formation. Herein, we show that intraoral submucosal injection of ABL, when combined with mechanical force, promotes in situ alveolar bone thickening. The newly formed bone is primarily located outside the original compact bone, implying its origin from the periosteum. RNA sequencing of the alveolar bone tissue revealed that the focal adhesion (FA) pathway potentially mediates this bioprocess. Local injection of ABL alone enhances cell proliferation, collagen synthesis, and phosphorylation of focal adhesion kinase (FAK) in the alveolar periosteum; when ABL is combined with mechanical force, the FAK expression is upregulated, in line with the accomplishment of the ossification. In vitro, ABL enhances proliferation, migration, and FAK phosphorylation in periosteal stem cells. Furthermore, the pro-osteogenic effects of ABL on alveolar bone are entirely blocked when FAK activity is inhibited by a specific inhibitor. In summary, abaloparatide combined with mechanical force promotes alveolar bone formation via FAK-mediated periosteal osteogenesis. Thus, we have introduced a promising therapeutic approach for drug-induced in situ alveolar bone augmentation, which may prevent or repair the detrimental periodontal dehiscence, holding significant potential in dentistry.
Osteogenesis/drug effects* ; Periosteum/cytology* ; Parathyroid Hormone-Related Protein/administration & dosage* ; Animals ; Focal Adhesion Protein-Tyrosine Kinases/metabolism* ; Alveolar Process/drug effects* ; Cell Proliferation/drug effects* ; Phosphorylation ; Rats ; Male ; Humans ; Focal Adhesion Kinase 1/metabolism* ; Cell Movement/drug effects*

Objective:To establish an animal model of trans-sutural distraction osteogenesis in SD rats.Methods:A self-designed V-shaped distraction device(distractor)was fabricated with the traction force(N)of 0,1.3,2.2,3.0,4.3 and 5.0 corresponding to the distraction length(mm)of 5,4,3,2,1 and 0 respectively,meeting the trans-sutural distraction osteogenesis requirements in skull of 5-week-old SD rats.The distractor was plased into the sagittal suture of 12 SD rats.Continuous sampling was conducted 1,3,5 and 7 days respectively(n=3)after operation.The tissue changes in the trans-sutural distraction area were observed by HE and Masson's trichrome staining.Inflammation levels were determined using Arg-1 immunofluorescence staining.The early angiogenesis was clarified through co-staining with CD31 and EMCN.Results:A stable trans-sutural distraction osteogenesis model was estab-lished,5 mm distraction osteogenesis width was observed completely within 7 days of distraction.Significant new bone formation was observed at 7 days after operation.Arg-1 expression increased and was concentrated at the bone margins,overlapping with the areas of new bone formation.EMCN expression gradually decreased,and by day 7 CD31 was predominant,indicating the basic maturation of blood vessels.Conclusion:This study successfully constructed a stable and effective trans-sutural distraction osteogenesis animal model,and provides an experimental basis for the investigation of its early continuous histological changes.

The functional health and stability of the oral and maxillofacial system is one of the basic goals of orth-odontic treatment.Currently,it is believed that,in general,the condyle is located in the center of the joint fossa when the mandible is in an intercuspal position(ICP)in healthy normal people.At this time,the function of the temporoman-dibular joint(TMJ)is stable.Due to orthodontic tooth movement and subsequent occlusal changes,patients with maloc-clusion may experience related remodeling of the temporomandibular joint,especially changes in the position of the con-dyle.The position of the mandibular condyle is traditionally evaluated using a condylar position indicator.However,this method lacks consistency in obtaining condylar position changes.In recent years,in the clinical application of orthodon-tic treatment,cone beam computed tomography(CBCT)has become the first choice for examination.CBCT can accurate-ly measure the interarticular space and determine changes in condylar position.This article reviews the CBCT assess-ment of condylar position and related research on condylar position changes in patients with malocclusion before and af-ter orthodontic treatment.The literature review results indicate that there are differences in the condylar position of pa-tients with different malocclusions,and the condylar position may also change before and after orthodontic treatment.With a lower radiation dose,CBCT has higher accuracy in evaluating the condylar position in patients with malocclu-sion who undergo orthodontic treatment,thus promoting further study of the mechanism of condylar position changes in patients with malocclusion in the future and providing more accurate and personalized guidance for patient treatment.

To introduce the modified pharyngeal flap of bilateral muscular rings (BMR), and to discuss the clinical effect of this operation in the correction of moderate and severe velopharyngeal insufficiency. The clinical data of 18 patients who underwent BMR surgery in the Department of Craniofacial Plastic and Aesthetic Surgery, School of Stomatology, The Fourth Military Medical University from May 2019 to July 2021 were retrospectively analyzed. There were 10 males and 8 females, with a median age of 8.5 years (aged from 5 to 34 years). The patients were diagnosed preoperatively with moderate to severe velopharyngeal insufficiency (velopharyngeal closure ratio<0.7). The results of nasopharyngoscopy and speech assessment were compared and analyzed before operation and at the follow-up 6 months after the operation to evaluate the changes in velopharyngeal function and speech. Eighteen patients underwent BMR, 4 patients had snoring (the symptom disappeared after a few weeks in 3 cases), and 2 patients had local erosion of the wound, which delayed healing. Postoperative nasopharyngoscopy showed that all patients achieved comparatively complete velopharyngeal closure, some patients got enhanced lateral pharyngeal wall motility, and all patients got active motility of posterior pharyngeal wall flap. The postoperative speech assessment was significantly improved compared with that before the operation. The preoperative median score was 9 (range 7-12), and the postoperative median score was 2 (range 0-4). The statistical analysis was performed by paired non-parametric Wilcoxon signed rank test, and the difference was statistically significant ( P<0.001). BMR is a reliable method for the treatment of moderate and severe velopharyngeal insufficiency. This technique can achieve functional contraction of the full circumference of the ventilator while preserving the obstructive effect of the posterior pharyngeal wall flap, which is helpful to balance nasal ventilation and velopharyngeal closure and improve the velopharyngeal function of patients.

Objective:To explore the effect of nursing intervention based on self-regulation theory on the self-care ability and mood state of patients with hepatitis B.Methods:From July 2021 to June 2023, a total of 126 patients with hepatitis B in the Department of Infectious Diseases in the First Affiliated Hospital of Zhengzhou University were selected as the research objects by the convenient sampling method. They were divided into the control group ( n=63) and the intervention group ( n=63) using the simple random number method. The control group received routine nursing intervention, while the intervention group received nursing intervention based on self-regulation theory based on routine nursing intervention. The intervention period was six months. Self-care ability, mood state, regular follow-up rate, medication compliance rate, and nursing satisfaction before and after intervention were compared between the two groups. Results:After six months of intervention, the score of the Exercise of Self-Care Agency Scale (ESCA) and the score of energy dimension in Profile of Mood states-short form (POMS-SF) in the intervention group were both higher than those in the control group? ( P<0.05), while scores of confusion, fatigue, anger, tension, and depression dimensions in POMS-SF were lower than those in the control group ( P<0.05). The intervention group's regular follow-up rate, medication compliance rate, and nursing satisfaction were all higher than those of the control group ( P<0.05) . Conclusions:Nursing intervention under the theoretical framework of self-regulation can improve the self-care ability of hepatitis B patients, their mood state, the regular follow-up rate, medication compliance rate, and nursing satisfaction.

Objective : To evaluate the effect of platelet-rich fibrin (PRF) on orthodontic tooth movement (OTM) and to provide a basis for clinical application. Methods: Literature searches were conducted in 7 electronic databases supplemented with a hand search. Randomized controlled trials focusing on OTM with PRF were included. The risk of bias was assessed by the Cochrane tool. Finally, due to the heterogeneity of patient clinical characteristics and research methods, the results in every study were qualitatively described. Results: Six studies were included. Five studies were split-mouth designs, and 1 was a two-arm parallel design. Two studies used leukocyte- and platelet-rich fibrin, while the other 4 used injectable PRF. The risk of bias of 3 studies was graded as “Some concerns”, and 3 were graded as “Low risk”. The trials lasted from 4 weeks to 5 months. Four studies supported that PRF could accelerate OTM, 1 study demonstrated that PRF had no effect on OTM, and 1 study reported that PRF decreased OTM. There is moderate-quality evidence that PRF accelerates OTM in the first 3 months after application, while low-quality evidence supports that PRF loses its tooth-acceleration effect after 4 months. Conclusion Limited clinical evidence suggests that PRF could accelerate OTM in the early stages, but its long-term effect needs clarification.

The biomolecular mechanisms that regulate tooth root development and odontoblast differentiation are poorly understood. We found that Atp6i deficient mice (Atp6i^-/-) arrested tooth root formation, indicated by truncated Hertwig's epithelial root sheath (HERS) progression. Furthermore, Atp6i deficiency significantly reduced the proliferation and differentiation of radicular odontogenic cells responsible for root formation. Atp6i^-/- mice had largely decreased expression of odontoblast differentiation marker gene expression profiles (Col1a1, Nfic, Dspp, and Osx) in the alveolar bone. Atp6i^-/- mice sample RNA-seq analysis results showed decreased expression levels of odontoblast markers. Additionally, there was a significant reduction in Smad2/3 activation, inhibiting transforming growth factor-β (TGF-β) signaling in Atp6i^-/- odontoblasts. Through treating pulp precursor cells with Atp6i^-/- or wild-type OC bone resorption-conditioned medium, we found the latter medium to promote odontoblast differentiation, as shown by increased odontoblast differentiation marker genes expression (Nfic, Dspp, Osx, and Runx2). This increased expression was significantly blocked by anti-TGF-β1 antibody neutralization, whereas odontoblast differentiation and Smad2/3 activation were significantly attenuated by Atp6i^-/- OC conditioned medium. Importantly, ectopic TGF-β1 partially rescued root development and root dentin deposition of Atp6i^-/- mice tooth germs were transplanted under mouse kidney capsules. Collectively, our novel data shows that the prevention of TGF-β1 release from the alveolar bone matrix due to OC dysfunction may lead to osteopetrosis-associated root formation via impaired radicular odontoblast differentiation. As such, this study uncovers TGF-β1 /Smad2/3 as a key signaling pathway regulating odontoblast differentiation and tooth root formation and may contribute to future therapeutic approaches to tooth root regeneration.
Female ; Animals ; Mice ; Transforming Growth Factor beta1 ; Odontoblasts ; Culture Media, Conditioned ; Cell Differentiation ; Signal Transduction ; Disease Models, Animal ; Tooth Root