OBJECTIVES: This study aimed to conduct a meta-analysis of the efficacy of mandibular advance clear alig-ners with traditional functional appliances as the control group. METHODS: PubMed, Web of Science, Embase, Cochrane Library, China Biomedical Abstracts Database, China Knowledge Network Database, Wanfang Database, and Weipu Database were used in this study. The two groups of researchers screened the literature and extracted data based on the inclusion and exclusion criteria established by PICOS entries, and used the ROBINS-I scale for quality evaluation. Revman 5.4 and Stata 17.0 software were used for meta-analysis. RESULTS: Nine clinical controlled trials were included in this study with a total sample size of 283 cases. No significant difference was found in SNA, SNB, ANB, Go-Pog, U1-SN, Overjet, and other aspects between the invisible group and the traditional group in the treatment of skeletal class Ⅱ ma-locclusion patients; there was a 0.90° difference in mandibular plane angle between the two groups; the growth of the mandibular ramus (Co-Go) in the traditional group was 1.10 mm more than that in the invisible group; the lip inclination of the lower teeth in the invisible group was better controlled, 1.94° less than that in the control group. CONCLUSIONS The invisible group can better control the lip inclination of the mandibular anterior teeth when guiding the mandible. Furthermore, the mandibular plane angle (MP-SN) can remain unchanged, but the growth of the mandibular ramus is not as good as the traditional group, and auxiliary measures should be taken to improve it in clinical practice.
Humans ; Malocclusion, Angle Class II/therapy* ; Mandibular Advancement ; Orthodontics, Corrective ; Orthodontic Appliances, Functional ; Mandible ; Orthodontic Appliances, Removable ; Cephalometry

OBJECTIVES: To evaluate the effects of a Twin-block appliance on the condyles of patients with ClassⅡmalocclusion by conducting a systematic review and a Meta-analysis. METHODS: Pubmed, Embase, Cochrane Library, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and VIP Database were electronically searched. Randomized controlled trials, controlled clinical trials, and single-arm trials on condylar changes produced by a Twin-block appliance in patients with ClassⅡmalocclusion were included. Two reviewers independently extracted and assessed the risk of bias. Meta-analyses were conducted with Review Manager 5.3. RESULTS: Eight studies were included; among which, seven were of high quality. After treatment with a twin block appliance, condyles moved anteriorly. The anterior joint spaces decreased (P<0.000 01), whereas the posterior spaces increased (P<0.000 01). The superior spaces were not changed (P=0.11). Moreover, a significant difference was observed in the increase of the condylar space index (P<0.000 01). After treatment, the anteroposterior diameters of the condyles and condylar height increased (P=0.000 2 and P<0.000 01, respectively). By contrast, no significant changes were discovered in the medial external diameters of the condyles (P=0.42). CONCLUSIONS A Twin-block appliance can promote the growth of a condyle in the posterior and upper direction and move it forward in favor of the correction of Class Ⅱ malocclusion.
Humans ; Malocclusion, Angle Class II/therapy* ; Temporomandibular Joint ; Bone and Bones ; China ; Orthodontic Appliances, Functional ; Cephalometry

In recent years, the early orthodontic treatment of malocclusion has become a hot issue in the field of orthodontics. Some new phenomena and new problems that have emerged require in-depth analysis and discussion, and need to be given correct guidance and norms. Malocclusion refers to the deformities of teeth, jaws, and craniofacial bones caused by genetic and environmental factors during growth and development. Based on the accurate judgment of the etiology and diagnosis, choosing the right time and suitable indications, with the advantage of growth and development, the most suitable appliance can be selected in the early stage of malocclusion to fix malocclusion, and to effectively prevent and block the formation and development of malocclusion. This article will discuss how to timely and appropriately carry out the early prevention and treatment of malocclusion with six aspects, including methods of performing early orthodontic treatment, the basis and guarantee of early orthodontic treatment, correctly understanding early orthodontic treatment, the issues that should be paid attention to in carrying out early orthodontic treatment, actively advocating multidisciplinary cooperation during early orthodontic treatment and understanding face management in a serious way.
Dental Care ; Humans ; Malocclusion/therapy* ; Malocclusion, Angle Class II/therapy* ; Orthodontic Appliances, Functional ; Orthodontics, Corrective/methods*

The early orthodontic treatment of malocclusion includes the growth modification of skeletal discrepancy, preventive and interceptive orthodontic treatment of the dental malocclusion or oral habit. Therefore, early orthodontic treatment is to guide the normal dento-maxillafacial growth and development, eliminate the adverse effect on function of masticatory system and the health of dental and periodontal tissues. Most of the patients in the early permanent dentition are still in their pubertal growth period. Although all kind of comprehensive orthodontic treatment could be started from early permanent dentition, early orthodontic treatment can still be used in the cases such as class Ⅱ malocclusion caused by underdevelopment of mandible and crossbite caused by underdevelopment of maxilla in the early permanent dentition. The article will discuss class Ⅱ malocclusion caused by underdevelopment of mandible and anterior and posterior crossbite caused by underdevelopment of maxilla which are feasible for early orthodontic treatment.
Dentition, Mixed ; Dentition, Permanent ; Humans ; Malocclusion/therapy* ; Malocclusion, Angle Class II/therapy* ; Maxilla

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. CONCLUSION 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.
Bicuspid ; Cephalometry/methods* ; Female ; Humans ; Male ; Malocclusion, Angle Class II/therapy* ; Mandible ; Maxilla/diagnostic imaging* ; Orthodontic Anchorage Procedures ; Tooth Movement Techniques ; Vertical Dimension

To evaluate the therapeutic effect of using micro-implant anchorage (MIA) to rotate the functional occlusal plane (FOP) counterclockwise. Forty skeletal class Ⅱ high-angle patients who had completed orthodontic treatment were enrolled, including 20 patients treated with MIA orthodontic system (MIA group) and the other 20 patients treated with traditional sliding straight wire appliance (control group). Cephalometric measurements on the lateral cranial radiographs before and after treatment were performed, all acquired data were statistically analyzed with SPSS 26.0. At the end of treatment, MIA group obtained better effect of FOP and mandibular plane counter-clockwise rotation than the control group. In the MIA group, the average change of FOP-frankfort horizontal plane (FH), FOP-SN and mandibular plane angle (MP-FH) angle was -4.5(-7.3, -3.7)°, (3.3)° and -1.7(-3.0, -0.9)°, respectively. In the control group, the average change of FOP-FH, FOP-SN and MP-FH angle was -0.1(-4.1, 3.0)°, (-0.1±5.1)° and -0.4(-2.4, 0.7)°, respectively. There was significant difference between the change of the two groups (all <0.05). Compared with the traditional sliding straight wire appliance, counterclockwise rotation of FOP can be more effectively reversed by using MIA orthodontic system, and the MP-FH can be reduced as well.
Cephalometry ; Dental Occlusion ; Humans ; Malocclusion, Angle Class II/therapy* ; Mandible ; Maxilla ; Treatment Outcome

This case report describes the treatment of a 25-year-old woman with a severe open bite. This patient presented a grade Ⅲ open bite, considerably thin alveolar bone, and evident labial buccal and lingual root form. The open bite was corrected by fixed orthodontic treatment and masticatory exercises. However, the increased pressure in the labial muscle caused by lip muscle exercise suppressed the canines, which resulted in the protrusion of the apices of canine roots out of the alveolar bone. Afterward, HX brackets, instead of self-locking, were used and bonded reversely in the occlusal-gingival direction on the upper canines. The lip muscle exercises were decreased. After adjustment, the roots penetrated back into the cancellous bone, the severe open bite was corrected, and a normal overbite and overjet were achieved. ClassⅠcanine and molar relationships were established. The masticatory function and profile were both considerably improved. This case report showed that a severe nonskeletal open bite can be corrected using orthodontic treatments combined with masticatory exercises.
Adult ; Cephalometry ; Female ; Humans ; Malocclusion, Angle Class II ; Open Bite ; therapy ; Overbite ; Tooth Movement Techniques

This study aimed to assess the reliability of experienced Chinese orthodontists in evaluating treatment outcome and to determine the correlations between three diagnostic information sources. Sixty-nine experienced Chinese orthodontic specialists each evaluated the outcome of orthodontic treatment of 108 Chinese patients. Three different information sources: study casts (SC), lateral cephalometric X-ray images (LX) and facial photographs (PH) were generated at the end of treatment for 108 patients selected randomly from six orthodontic treatment centers throughout China. Six different assessments of treatment outcome were made by each orthodontist using data from the three information sources separately and in combination. Each assessment included both ranking and grading for each patient. The rankings of each of the 69 judges for the 108 patients were correlated with the rankings of each of the other judges yielding 13 873 Spearman rs values, ranging from -0.08 to +0.85. Of these, 90% were greater than 0.4, showing moderate-to-high consistency among the 69 orthodontists. In the combined evaluations, study casts were the most significant predictive component (R(2)=0.86, P<0.000 1), while the inclusion of lateral cephalometric films and facial photographs also contributed to a more comprehensive assessment (R(2)=0.96, P<0.000 1). Grading scores for SC+LX and SC+PH were highly significantly correlated with those for SC+LX+PH (r(SC+LX)vs.(SC+LX+PH)=0.96, r(SC+PH)vs.(SC+LX+PH)=0.97), showing that either SC+LX or SC+PH is an excellent substitute for all three combined assessment.
Adolescent ; Cephalometry ; standards ; China ; Dental Models ; standards ; Esthetics, Dental ; Female ; Humans ; Male ; Malocclusion, Angle Class I ; therapy ; Malocclusion, Angle Class II ; therapy ; Malocclusion, Angle Class III ; therapy ; Orthodontics ; standards ; Peer Review, Health Care ; standards ; Photography ; standards ; Reproducibility of Results ; Treatment Outcome

The effects of Tip-Edge plus appliance in the treatment of Angle II(1) malocclusion and the mechanism were investigated. Fifty-two Angle II(1) children, aged from 12.3-14.2 years, with mandibular retrusion in permanent dentition were selected and treated with Tip-Edge plus appliance. Lateral cephalometric films taken before and after treatment were analyzed. The arithmetic mean and standard deviation were calculated for each variable. Paired t-test was performed to evaluate the significant treatment change. Results showed that the average treatment time was 16 months. Normal overjet and overbite were established with retroclination of upper incisors and proclination of lower incisors. U1-NA was decreased by 15.4° (P<0.01). ANB and Y axial angle were decreased significantly (P<0.05). Soft tissue measurements showed that FCA and UL-E were decreased dramatically (P<0.05), and LL-E was increased significantly (P<0.05). Remarkable soft tissue change was noted after the treatment and convex facial profile changed to the straight profile. In conclusion, Tip-Edge plus technique can quickly and efficiently correct anterior bite and lateral outlook.
Adolescent ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; therapy ; Orthodontic Appliances

OBJECTIVETo investigate the soft and hard tissue changes in Class II division 1 patients treated with Tip-Edge plus technique.

METHODSSixteen Class II division 1 patients (7 boys and 9 girls) with mandibular retrusion in permanent dentition were selected and treated with Tip-Edge plus appliance. Lateral cephalometric films were analyzed before and after treatment. The effects were evaluated with Holdaway soft tissues analysis and routine cephalometric analysis methods. The arithmetic mean and standard deviation were calculated for each variable. Paired t-test was performed.

RESULTSThe average treatment time was 16 months. Normal overjet and overbite were established with retroclination of upper incisors and proclination of lower incisors. U1-NA(°) and U1-NA (mm) decreaed by (15.40 ± 5.31)° and (4.16 ± 1.82) mm (P < 0.01). NLA showed an average increase of (-16.60 ± 5.29)° (P < 0.01). Remarkable soft tissue change was noted after the treatment.

CONCLUSIONSThe profile in Class II division 1 patients could be quickly and efficiently improved after treatment with Tip-Edge plus technique.

Adolescent ; Cephalometry ; Child ; Esthetics, Dental ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; diagnostic imaging ; therapy ; Orthodontic Wires ; Orthodontics, Corrective ; instrumentation ; methods ; Radiography, Panoramic