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

OBJECTIVETo determine the positional changes of condyle and mandible in children treated successfully with Fränkel function regulator.

METHODS30 Angle's class II patients including 15 boys and 15 girls treated with Fränkel function regulator were selected. Superimposition of the pretreatment and posttreatment lateral cephalograms of all the patients was done on the stable bone structure of the anterior cranial base and mandible. Cartesian coordinate system was used to measure the positional changes of condyle and mandible over time by computer.

RESULTSThere was significant inferior displacement of condyle, gonion and pogonion after treatment with reference to stable bone structure of anterior cranial base. Anterior displacement of pogonion in boys was also significant. There was significantly superior and posterior displacement of condyle and posterior displacement of gonion after treatment with reference to stable bone structure of mandible.

CONCLUSIONFränkel function regulator can stimulate condylar growth and do favor to mandibular remolding.

Activator Appliances ; Cephalometry ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; therapy ; Orthodontic Appliances, Functional

OBJECTIVESkeletal and dental changes during treatment and six months post-treatment with the headgear-Herbst appliance were evaluated quantitatively.

METHODSThe sample comprised of 22 treated patients and 31 controls. Lateral cephalograms were obtained at start, after 6 months and end of active treatment, and after 6 months of retention.

RESULTSThe restraint effect on the maxilla was significant in both initial and late phases, the enhanced growth of the mandible was significant during the initial phase only, while there was effect of reduced increase in lower facial height during the late phase only. During retention period the jaw base relationship was maintained and the effect on the lower facial height was reinforced.

CONCLUSIONThe Headgear Herbst was effective orthopedic devise.

Adolescent ; Child ; Extraoral Traction Appliances ; Humans ; Malocclusion, Angle Class II ; therapy ; Mandibular Advancement ; methods ; Orthodontic Appliances, Functional ; Prospective Studies ; Treatment Outcome

The aim of this study was to compare the pain experience among orthodontic patients treated with self-ligating brackets SmartClip® (3M Unitek, Monrovia, California, USA) and conventional brackets Victory series® (3M Unitek, Monrovia, California, USA). We used a controlled clinical trial study design to compare 69 patients treated with self-ligating to 70 patients treated by conventional brackets. The nickel-titanium archwires 0.012-in were engaged after bonding both arches on the first day; and the visual analogue scale (VAS) was used to assess the pain experience of subjects for the first seven treatment days. The pre-treatment dental study models were assessed by the Little’s irregularity index to quantify the groups’ malalignment characteristics. The self-ligating brackets reported lower pain experience than the conventional group on the first five treatment days. However, the sixth day showed 1.75 mm higher visual analogue score than conventional brackets, with almost equal pain level on the seventh day. The group differences throughout the first week were neither clinically nor statistically significant. The pain experiences in both groups decreased steadily from the third treatment day to the end of the first week of treatment. Based on the study findings, the pain experience during initial alignment is not influenced by the brackets’ ligation type. The pain experience tends to decrease steadily from the third treatment day to the end of the first week of treatment irrespective of the bracket type used.
Orthodontic Brackets, Orthodontic Appliances

OBJECTIVETo compare patient satisfaction with two type of Twin-block by clinic complain questionnaire, treatment effect satisfaction questionnaire and total satisfaction questionnaire, and to analyse their related factors with patient satisfaction.

METHODS56 patients were randomly classified into fixed-Twin-block (TB1) and unfixed-Twin-block (TB2). The complaint and satisfaction of patients was evaluated by clinic complain questionnaire, treatment effect satisfaction questionnaire and total satisfaction questionnaire after 10 days and 6 months of treatment.

RESULTS(1) There was significant difference between the complaint of two groups in the sixth month, but there was no difference in the tenth day. (2) There was significant difference between the total satisfactory degree of two groups. (3) There was significant difference between the tooth-jaw effective index and the mandible effective index of the two groups.

CONCLUSIONThe satisfactory degree of fixed-Twin-block is superior to that of unfixed-Twin-block. The adorn fashion, treatment stage and functional position has influence on patient satisfaction.

Female ; Humans ; Male ; Mandible ; Orthodontic Appliances, Functional ; Patient Satisfaction ; Tooth

The content of the guidelines is based on monographs and literatures on the clear aligner orthodontic treatment in the past five years, and the clinical consensus of all the members of Expert Group for Writing Project of Clear Aligner Technology. This guidelines provide guidance and reference for orthodontists who want carry out clear aligner orthodontic treatment in three parts: overview, diagnosis and design, and common treatment strategies. In the part of the overview, the instructions for the preparation of this guide were described. The requirements for practitioners providing clear aligner orthodontic treatment were put forward, and the risks associated with clear aligner orthodontic treatment were suggested. In the part of diagnosis and design, the indications and selection of clear aligner orthodontic treatment were defined. The requirements of collecting data in orthodontic cases and the design process of clear aligner orthodontic treatment were also explained. The present common treatment strategies for clear aligner orthodontic treatment were summarized in the third part of the guidelines. The elaboration of the treatment methods such as distalization of molar, interproximal enamel reduction and stepwise tooth movement were explained.
Dental Care ; Humans ; Molar ; Orthodontic Appliances, Removable ; Tooth Movement Techniques

OBJECTIVES: At present, the research on clear aligner of molar distalization mainly focuses on the upper jaw, while the research on mandibular molars is few.This study aims to evaluate the therapeutic effect of mandibular molars distalization with clear aligner via cone beam CT (CBCT) and Dolphin software. METHODS: Twenty cases of mandibular molars with clear aligner were included according to the inclusion and exclusion criteria. CBCT was taken before treatment (T0) and when the first molar was moved in place (T1). Dolphin software was used to measure the effectiveness of molar distalization. Three-dimensional changes in direction and the impact on the incisors and facial soft and hard tissues were evaluated. RESULTS: The effective rates of crown and root distalization of the second and first mandibular molars were 74%, 49%, and 71%, 47%, respectively. The second and first molars were both the distal buccal cusp with the largest distalization [(2.15 ± 0.91) mm and (1.85±1.09) mm], respectively, with significant difference between the T0 and T1 ( CONCLUSIONS Clear aligner can effectively move mandibular molars farther, the crown is more effective than the root, and it is tilted. The second mandibular molar is more effective than the first mandibular molar in its distant displacement and three-dimensional changes. Molar distalization causes minor changes in mandibular incisors and facial soft and hard tissues.
Cephalometry ; Maxilla ; Molar ; Orthodontic Appliances, Removable ; Tooth Movement Techniques

Child ; Extraoral Traction Appliances ; Humans ; Molar ; Orthodontic Wires ; Orthodontics, Interceptive ; instrumentation ; Prognosis ; Time Factors ; Tooth Crown ; surgery ; Tooth Eruption, Ectopic ; surgery ; therapy ; Tooth Movement Techniques ; instrumentation ; methods

OBJECTIVETo evaluate whether there was any difference on the clinical effects of Twin-block, Activator and Herbst appliances on the clinical effects of growing children with skeletal Class II malocclusion.

METHODS60 patients with skeletal Angle Class II malocclusion were divided into three groups (Twin-block group, Activator group, Herbst group), 20 in each group. The patients of three groups were respectively treated by Twin-block, Activator and Herbst appliances. The patients were 10-13 years old(mean 11.6) before treatment, and were mainly with mandibular retrognathia. Data of pre- and post-treatment were measured and analyzed.

RESULTSThere was statistically significance of ANB, SNB, Go-Gn, Co-Gn, L1-MP in sagittal changes, and N-Me, ANS-Me, S-Go, SN-MP, Co-Go in vertical changes after treatment of three groups. Herbst group was more effective than Twin-block group and Activator group in the increase of L1-MP, but the effects on maxilla were not significant among them. There was no statistical significance of Ptm-A, OB, N-Me, ANS-Me, S-Go and Co-Go between 3 groups.

CONCLUSIONTreatment effects of three different functional appliances (Twin-block, Activator and Herbst) are similar in the early treatment of skeletal Class II malocclusion. Compared with Twin-block and Activator, Herbst has more effects on orthopedic of mandibular and lower anterior teeth.

Adolescent ; Cephalometry ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; Mandible ; Maxilla ; Orthodontic Appliances, Functional

OBJECTIVETo examine the hypothesis that functional appliances enhance mandibular growth in the treatment of skeletal Class II malocclusion.

METHODSA literature search was performed in electronic databases according key words "skeletal Class II malocclusion" , and full texts of selected articles were collected by hand-made method. The data were extracted from the articles. The quality of the trials was evaluated and meta-analysis method was used to analyze the data through RevMan 4.2.

RESULTS19 articles could be qualified for the final analysis. Those indices including SNB (Activator, Twin-block, Herbst group), Go-Gn, Co-Pg, Co-Gn, Co-Go, demonstrated significant effect of functional appliances on mandibular growth in comparing with those of untreated control group. There were no significant differences between the two groups for the indicies of SNB (Fränkel-II) and Go-Me.

CONCLUSIONFunctional appliances can enhance mandibular growth in treatment of skeletal Class II malocclusion. This mainly dues to the growth of the ramus instead of changes of mandibular body length.

Cephalometry ; Humans ; Malocclusion ; Malocclusion, Angle Class II ; Mandible ; Orthodontic Appliances, Functional