The application of clear aligner technique in the preventive and interceptive treatment of children with malocclusion is a new hot spot in orthodontics, which has an extensive application prospect. However, the main advantage of this technique is the ability of predictable tooth movements. Early treatment of malocclusion often involves many aspects, such as muscle function adjustment, orthopedic treatment, and dentition replacement monitoring, etc. Therefore, the indications should be strictly controlled to avoid abusing the technique. The digital treatment planning, clinical monitoring also should be deliberated. The key point is how to avoid the shortcomings of the technique, and to provide a more comfortable and effective early treatment method for children.

Appropriate torque control of anterior teeth is of great significance to obtain ideal orthodontic treatment outcome. Clear aligners are less effective in torque control of anterior teeth due to their special application mode and material properties. Therefore, it is important to investigate how to improve the torque control of anterior teeth by using clear aligners, with the expectation of providing guidance for clinicians. This article discussed the methods to control the torque of anterior teeth by using traditional fixed appliances, the efficiency of clear aligner in controlling the torque of anterior teeth, the difficult points of clear aligner in controlling the torque of anterior teeth and the therapeutic methods to better control the torque of anterior teeth by using clear aligners.

The treatment of skeletal Class III malocclusion in adolescents is challenging.Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized miniplates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage.The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400–500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

Early orthodontic treatment is an important means of preventing and treating dentofacial deformities during the period of growth and development. In this stage, children have great potential in growth and development, high adaptability of muscles and temporomandibular joint, and good responsiveness to orthodontic force. Therefore, orthodontic intervention and treatment in this stage can prevent and guide the normal growth and development of dentition, occlusion and maxillofacial complex. This article summarizes the commonly used orthodontic techniques and appliances in the mixed dentition, including interceptive treatment of oral habits, application of functional appliances, fixed appliances, clear aligners, as well as management of severe crowding and space maintenance. This article comprehensively explains the application and indications of different orthodontic techniques in design and appliance selection in the treatment of malocclusions in the mixed dentition.

With the advancement of digital healthcare and artificial intelligence (AI) technologies, the full automation of clear aligner orthodontic technology has become feasible. Significant research findings and commercial applications have emerged in areas such as intelligent diagnosis of multimodal orthodontic data, orthodontic treatment decision-making, automated generation of digital treatment plans, and remote intelligent monitoring. However, in the development and application of AI software, it is imperative to address issues related to clinical risks, target populations, and compliance with medical device software regulations. This article analyzes and summarizes the applications and challenges of AI in clear aligner orthodontic diagnosis, treatment, and production processes. Furthermore, it explores potential future trends in this field, providing valuable insights for clinical reference.

Objective:To develop an automated landmark location system applicable to the case of landmark missing.Methods:Four and eighty-one lateral cephalograms, which contained 240 males and 241 females, with an average age of (24.5±5.6) years, taken from January 2015 to January 2021 in the Department of Orthodontics, Capital Medical University School of Stomatology, and met the inclusion criteria were collected. Five postgraduate orthodontic students were the annotators to manually locate 61 possible landmarks in 481 lateral cephalograms. Two assistant professors in the department as reviewers performed calibration. Two professors as arbitrators, made final decision. Data sets were established (341 were used as training set, 40 as validation set, and 100 as test set). In this paper, an automatic landmarks identification and location model based on convolutional neural networks (CNN), CephaNET, was developed. The model was trained by feeding the original image into the feature extraction module and convolutional pose machine (CPM) module to locate landmarks with high accuracy using deep supervision. Training set was enhanced to 1 684 images by histogram equalization, cropping, and adjustment of brightness. The model was trained to compare the Gaussian heat maps output from the network with the set threshold to identify landmark missing cases. Test set of 100 lateral cephalograms was used to test the accuracy of the model. The evaluation criteria used were success detection rate of missing landmark, mean radial error (MRE) and success detection rate (SDR) in the range of 2.0, 2.5, 3.0, 3.5 and 4.0 mm.Results:The model identified and located 61 commonly used landmarks in 0.13 seconds on average. It had an average accuracy of 93.5% in identifying missing landmarks. The MRE of our testing set was (1.19±0.91) mm. SDR of 2.0, 2.5, 3.0, 3.5 and 4.0 mm were 85.4%, 90.2%, 93.5%, 95.4%, 97.0% respectively.Conclusions:The model proposed in this paper could adapt to the absence of landmark in lateral cephalograms and locate 61 commonly used landmarks with high accuracy to meet the requirements of different cephalometric analysis methods.

Objective:To compare the clinical efficacy of customized titanium plate and conventional maxillary protraction treatment in patients with skeletal class Ⅲ malocclusion during growth spurt.Methods:During growth spurt, skeletal class Ⅲ patients with maxillary hypoplasia who were treated in the Department of Orthodontics, Capital Medical University School of Stomatology from August 2018 to July 2021 were prospectively enrolled. They were treated with maxillary protraction using customized titanium plates (customized titanium plate group) and conventional methods (conventional protraction group), respectively. Lateral cephalometric radiographs were collected before and after treatment for conventional cephalometric analysis, including SNA angle (angle between Sella, Nasion and A point), ANB angle (angle between A point, Nasion, and B point), FH-MP angle (mandibular plane angle), Y-axis angle, U1-L1 angle (upper to lower central incisor angle), U1-SN angle (upper incisor to SN plane angle), anterior and lower height, maxillary length, etc. The stable basicranial line (SBL) was used as the reference line to measure the distance from each reference point (ANS point, A point, Prn point, Sn point, UL point etc.) to the stable basicranial vertical line (VerT, the perpendicular line of the skull base line at the intersection point of the anterior wall of the sella image and the inferior edge of the anterior bed process). Paired t-tests were performed on the cephalometric data before and after maxillary protraction treatment in the two groups, and two independent samples t-tests were performed to compare the differences in the efficacy of the two maxillary protraction methods. Results:A total of 20 patients (9 males and 11 females), aged (10.8±1.3) years, were included in the personalized titanium plate group. A total of 20 patients (8 males and 12 females), aged (10.5±1.1) years, were included in the conventional protraction group. The SNA angle, ANB angle, FH-MP angle, Y-axis angle, anterior lower height, maxillary length, ANS-VerT distance, A-VerT distance, Prn-VerT distance, Sn-VerT distance, and UL-VerT distance were significantly higher than those before treatment in the two groups ( P<0.05). The changes of SNA angle, ANB angle and A-VerT before and after treatment in the personalized titanium plate group [3.15°±2.28°, 4.64°±1.40°, (4.41±3.43) mm, respectively] were significantly higher than those in the traditional group [2.13°±2.69°, 2.81°±1.10°, (3.13±4.76) mm, respectively]( P<0.05), and the changes of U1-L1 angle and U1-SN angle before and after treatment (-0.76°±7.42° and 1.74°±6.38°, respectively) was significantly lower than that of the control group (-5.14°±6.62° and 4.57°±5.24°, respectively, P<0.05). Conclusions:Maxillary protraction can effectively improve skeletal class Ⅲ relationships in growing patients. The linear measurements using the SBL line as a reference plane visualize the sagittal improvement in sagittal relationship after maxillary protraction. The customized titanium plate maxillary protraction treatment has a clear therapeutic effect on patients with skeletal class Ⅲ deformities, and its dental effect is relatively small.

External apical root resorption is among the most common risks of orthodontic treatment, and it cannot be completely avoided and predicted. Risk factors causing orthodontic root resorption can generally be divided into patient- and treatment-related factors. Root resorption that occurs during orthodontic treatment is usually detected by radiographical examination. Mild or moderate root absorption usually does no obvious harm, but close attention is required. When severe root resorption occurs, it is generally recommended to suspend the treatment for 3 months for the cementum to be restored. To unify the risk factors of orthodontic root resorption and its clinical suggestions, we summarized the theoretical knowledge and clinical experience of more than 20 authoritative experts in orthodontics and related fields in China. After discussion and summarization, this consensus was made to provide reference for orthodontic clinical practice.
Humans ; Tooth Movement Techniques/adverse effects* ; Root Resorption/etiology* ; Consensus ; Dental Cementum ; Risk Factors