BACKGROUND: In this study, we sought to quantify the influence of vertical control assisted by a temporary anchorage device (TAD) on orthodontic treatment efficacy for skeletal class II patients with a hyperdivergent facial type and probe into the critical factors of profile improvement.
METHODS: A total of 36 adult patients with skeletal class II and a hyperdivergent facial type were included in this retrospective case-control study. To exclude the effect of sagittal anchorage reinforcement, the patients were divided into two groups: a maxillary maximum anchorage (MMA) group (N = 17), in which TADs were only used to help with anterior tooth retraction, and the MMA with vertical control (MMA + VC) group (N = 19), for which TADs were also used to intrude the maxillary molars and incisors. The treatment outcome was evaluated using dental, skeletal, and soft-tissue-related parameters via a cephalometric analysis and cast superimposition.
RESULTS: A significant decrease in ANB (P < 0.05 for both groups), the retraction and uprighting of the maxillary and mandibular incisors, and the retraction of protruded upper and lower lips were observed in both groups. Moreover, a significant intrusion of the maxillary molars was observed via the cephalometric analysis (- 1.56 ± 1.52 mm, P < 0.05) and cast superimposition (- 2.25 ± 1.03 mm, P < 0.05) of the MMA + VC group but not the MMA group, which resulted in a remarkable decrease in the mandibular plane angle (- 1.82 ± 1.38°, P < 0.05). The Z angle (15.25 ± 5.30°, P < 0.05) and Chin thickness (- 0.97 ± 0.45°, P < 0.05) also improved dramatically in the MMA + VC group, indicating a better profile and a relaxed mentalis. Multivariate regression showed that the improvement in the soft tissue was closely related to the counterclockwise rotation of the mandible plane (P < 0.05).
CONCLUSIONS: TAD-assisted vertical control can achieve intrusion of approximately 2 mm for the upper first molars and induce mandibular counterclockwise rotation of approximately 1.8°. Moreover, it is especially important for patients without sufficient retraction of the upper incisors or a satisfactory chin shape.

This case report describes successful orthodontic retreatment for vertical control with nonextraction orthodontic therapy. A 31-year-old woman complained of anterior open bite and crowding. She had slightly protrusive lips but wanted to correct her malocclusion without extraction. Two palatal temporary skeletal anchorage devices were used for the distalization of the maxillary arch along with posterior intrusion. Mandibular distalization was performed with Class III elastics. The duration of active treatment was 22 months. The plain and efficient mechanics used contributed to the effective distalization of both arches, the intrusion of the maxillary posterior teeth, and favorable profile changes. The results were still stable at the five-year follow-up period.

To investigate the differences in profile changes and stability of the condyles between orthodontic camouflage treatment assisted by vertical control and that accomplished via orthognathic surgery in Class II hyperdivergent patients with TMJ osteoarthrosis (TMJOA).
This study included 27 Class II hyperdivergent TMJOA patients (54 condyles) who received orthodontic camouflage treatment (13 patients) or orthognathic surgery (14 patients) Cone-beam computerized tomography (CBCT) scans were taken before treatment (T1) and 1 year after treatment (T2). Cephalometric and TMJ measurement analyses were conducted to evaluate the change in profile and condyles from T1 to T2 using independent samples t-test and paired t-test. Three-dimensional (3D) deviation analysis was also performed to evaluate the stability of condyles from T1 to T2.
Both groups showed significant profile improvement from T1 to T2. The changes in Z angle and ANB angle were larger in the surgical group than in the orthodontic group. Condylar width, length, and height remained stable after treatment in the orthodontic group (P > .05), while they reduced by 0.67 ± 0.85 mm, 1.14 ± 1.10 mm, and 1.07 ± 1.34 mm, respectively, in the surgical group (P < .05). Superior, posterior, medial, and lateral joint spaces were significantly reduced in the orthodontic group (P < .05). 3D deviations intuitively showed that condylar bone in the orthodontic group was more stable than that in the surgical group.
For Class II hyperdivergent patients with severe TMJOA, orthodontic camouflage treatment with vertical control can effectively maintain the stability of condyles while significantly improving the profile. Surgical treatment yields a better profile but may increase the risk of condyle resorption.

OBJECTIVE: To compare the effectiveness of micro-implant (MI) and conventional anchorage (CA) in vertical control during orthodontic extraction treatment of class II adults and adolescents after pubertal growth peak.
METHODS: Literature search was conducted through Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP, China Biology Medicine (CBM), and other sources, from inception to December 2021. Randomized clinical trials (RCTs) and controlled clinical trials (CCTs) were included. Mean differences (MDs) with 95% confidence intervals (CIs) were conducted. A meta-analysis concerning change of mandibular plane, vertical change of upper and lower molar, change of occlusal plane, SNB, chin position, and profile was carried out.
RESULTS: A total of 10,669 records were identified in the database search, and 19 studies (10 RCTs and 9 CCTs) were included in the final analysis. Compared with CA, MI significantly decreased mandibular plane angle and intruded upper molars. No significant difference was found in vertical change of lower molars, occlusal plane, SNB, chin position, and profile.
CONCLUSIONS: MI seems to be more effective than CA in vertical control during orthodontic extraction treatment of class II adults and adolescents after pubertal growth peak.
CONCLUSIONS: MI should be given priority when considering the vertical control of class II patients, which is beneficial to the counterclockwise rotation of mandible or at least prevention of deterioration of the profile.

At present, there are still controversies about the influence of orthodontic treatment on the size of upper airway and the position of hyoid bone. We investigated the effect of orthodontic vertical control therapy on the size of the upper airway and position of the tongue and hyoid bone in adult patients with hyperdivergent skeletal Class II.
Overall, 15 adults with hyperdivergent skeletal Class II and normal occlusion, respectively, were selected as the experimental and control groups. The angle and line of the craniofacial structure, upper airway, hyoid bone position and three-dimensional (3D) upper airway indexes were measured using the Uceph 4.2.1 standard version and Mimics 21.0 software, respectively. The paired t-test, Wilcoxon symbol rank test, t-test of two independent samples, two independent sample nonparametric tests, Mann-Whitney U test, Pearson correlation analysis, the Univariate linear regression analysis and Multiple linear regression analysis were performed.
After treatment, the S-Go/N-Me (%) and the MP-SN and XiPm-SN angles were significantly different (P < 0.01). The U-MPW and PAS significantly increased (P < 0.05), sagittal diameter L2 increased significantly, and transverse diameter L2 decreased significantly (P < 0.01). Although no significant correlation was observed between the vertical change in the jaw and that in U-MPW and PAS, the sagittal diameter L2 showed a significant correlation (P < 0.05). The Multiple linear regression analysis showed that there was a significant negative correlation between the variables MP-SN and sagittal diameter L2 and positive correlation between S-Go/N-Me(%) and H-MP (P < 0.05). Furthermore, significant differences between the Hv (P < 0.01) and sagittal diameter L1(P < 0.05) were observed before and after treatment.
After the orthodontic vertical control therapy in patients with hyperdivergent skeletal Class II, the upper airway only underwent adaptive changes during treatment without substantial size changes, the position of tongue body and hyoid bone did not change significantly. Furthermore, compared with normal occlusion, the velopharyngeal segment airway of patients with hyperdivergent skeletal Class II remains narrow and long after treatment.

Severe hyperdivergent skeletal Class II malocclusion may be ideally treated with orthognathic surgery in adult patients. Here, we report a camouflage treatment of a 23-year-old female patient. She was diagnosed with a skeletal Class II malocclusion with extreme high mandibular plane angle, retrusive mandible, steep posterior occlusal plane, anterior open bite, and severe overjet. The treatment plan included extraction of all second premolars and intrusion of the maxillary anterior teeth and mandibular posterior teeth using miniscrews. These contributed to an effective counterclockwise rotation of the mandible, decreased lower face height, and improvement in anterior overbite. This case report shows a vertical control strategy on severe hyperdivergent skeletal Class II malocclusions, which achieves well-controlled sagittal and vertical dimensions and a favorable facial appearance. The treatment and retention results were well balanced and aesthetically pleasing.

OBJECTIVE: To investigate the efficacy of vertical control by using conventional mini-implant anchorage in maxillary posterior buccal area for Angle class Ⅱ extraction patients.
METHODS: Twenty-eight Angle class Ⅱ patients [9 males, 19 females, and age (22.6±2.8) years] were selected in this study. All of these patients were treated by using straight wire appliance with 4 premolars extraction and 2 mini-implant anchorage in maxillary posterior buccal area. In this study, the self-control method was used to measure and analyze the lateral radiographs taken before and after orthodontic treatment in each case, the main cephalometric analysis items were related to vertical changes. The digitized lateral radiographs were imported into Dolphin Imaging Software (version 11.5: Dolphin Imaging and Management Solutions, Chatsworth, California, USA), and marked points were traced. Each marked point was confirmed by two orthodontists. The same orthodontist performed measurement on the lateral radiographs over a period of time. All measurement items were required to be measured 3 times, and the average value was taken as the final measurement result.
RESULTS: Analysis of the cephalometric radiographs showed that, for vertical measurements after treatment, the differences of the following measurements were highly statistically significant (P < 0.001): SN-MP decreased by (1.40±1.45) degrees on average, FMA decreased by (1.58±1.32) degrees on average, the back-to-front height ratio (S-Go/N-Me) decreased by 1.42%±1.43% on average, Y-axis angle decreased by (1.03±0.99) degrees on average, face angle increases by (1.37±1.05) degree on average; The following measurements were statistically significant (P < 0.05): the average depression of the upper molars was (0.68±1.40) mm, and the average depression of the upper anterior teeth was (1.07±1.55) mm. The outcomes indicated that there was a certain degree of upper molar depression after the treatment, which produced a certain degree of counterclockwise rotation of the mandibular plane, resulting in a positive effect on the improvement of the profile.
CONCLUSIONS: The conventional micro-implant anchorage in maxillary posterior buccal area has a certain vertical control ability, and can give rise to a certain counterclockwise rotation of the mandible, which would improve the profile of Angle Class Ⅱ patients.

OBJECTIVE: To investigate the effects of long-term use of the lower lingual arch (LLA) on the sagittal and vertical positions of the permanent lower incisors and first molars.
METHODS: The sample consisted of 98 patients who were treated with an LLA (LLA group) and 39 patients who were treated without an LLA (no-LLA group). The positional changes of the lower incisors and first molars were analyzed after performing mandibular structural superimpositions on lateral cephalometric radiographs taken before treatment (T1) and at the end of LLA therapy (T2). The mean ages at T1 and T2 were 8.5 years and 13.2 years, respectively. Study casts were analyzed to quantify arch dimensional changes.
RESULTS: Mesial movement of the lower molar cusp was similar between the LLA and no-LLA groups, but the vertical position was slightly greater at T2 in the LLA group. In the LLA group, there was a molar tip-back effect, and the lower incisors were proclined 4.2° more than in the no-LLA group. Arch perimeter decreased 3.6 ± 2.6 mm without an LLA and 0.97 ± 3.7 mm with an LLA. Intercanine and intermolar widths both increased about 1 mm more with an LLA (P < .0001).
CONCLUSIONS: The LLA does not seem to restrict mesial movement and vertical eruption of the lower incisors and molars in the long term. The LLA effectively preserves the arch perimeter at the expense of a slight lower incisor proclination.

Idiopathic condylar resorption (ICR) is a rare, destructive temporomandibular joint disease characterised by progressive resorption of the condyles. This case report presents a record of an orthodontically treated patient with ICR with favourable posttreatment remodelling of the condyles. An 18-year-old woman sought treatment for ICR. A severe Class II high-angle facial pattern with resorption of bilateral condyles was evident. The treatment plan was determined after careful examination of condylar radiographs and comprised forward rotation of the mandible through full-arch intrusion with microimplants after extraction of the four premolars. The treatment was completed in 35 months, and the patient was noted to have a straight profile, good interdigitation and slightly increased condylar volume. Two years after retention, the condyles were stable, and the patient\'s profile and occlusion remained acceptable despite a mild relapse of the mandibular position. ICR was successfully corrected with orthodontic treatment. Counter-clockwise mechanics applied during the ICR remission period not only improved facial aesthetics but were also suitable for condylar unloading.

This study aims to evaluate the long-term stability of vertical control in hyperdivergent patients treated with temporary anchorage devices. The sample included 20 hyperdivergent patients without anterior open bite. The temporary anchorage devices were used to intrude the upper incisor and molars for vertical control. Lateral cephalograms were established prior to treatment, immediately after treatment, and during retention. The upper molars and incisors were intruded by 1.33 mm and 1.41 mm after treatment (P<0.05). U6-PP increased by 0.11 mm and 0.23 mm during the first and second stages of retention (P>0.05). U1-PP was found to possess a significant extrusion of 1.2 mm during the first stage (P<0.05), which increased by 0.68 mm during the second stage (P>0.05). The mandibular plane angle (MP-SN) decreased by 2.58 degrees following treatment, and underwent a relapse of 0.51 degree and 0.42 degree during the first and second stages of retention respectively (P>0.05). No significant soft tissue changes occurred, with the exception of increased upper lip length during the second stage (P<0.05). Maxillary anterior and posterior intrusions, counter clockwise rotation of the mandibular plane, and improved profiles can be successfully achieved following treatment with vertical control. During the first stage of retention (less than three years), intruded molars and incisors both exhibited some extrusion, and molars had better long-term stability than incisors. During the second stage of retention (three to six years), the therapeutic effects appeared stable, with the exception of some increase in upper lip length. Rotated mandibular plane remained stable during the entire retention period.