Prospective study of dentoskeletal changes in Class II division malocclusion treatment with twin force bite corrector

Assessment of the condylar response of two differently anchored fixed functional appliances in class II malocclusion in young adult orthodontic patients: A randomized clinical trial

OBJECTIVE

Measuring the condylar volume changes after treatment with skeletally anchored type IV Herbst appliance vs. Twin Force Bite Corrector (TFBC) in class II malocclusion in young adult patients.

MATERIALS AND METHODS

Twenty class II malocclusion participants were randomly involved in our randomized clinical study. They are divided equally into two groups: group I (10 patients with an age range of 16 to 18 years and a mean age of (17.15 ± 0.62) (five males and five females) with a mean Angle formed between (A) point and (Nasion) point and (B) point, to determine anteroposterior relation between maxilla and mandible (ANB) of 6.20 (1.03) and a mean mandibular length of 106.1 (1.7), who were treated by a skeletally anchored type IV Herbst appliance, supported at the mandible by two mini-plates fixed bilaterally at the mandibular symphysis; group II (10 patients with an age range of 15 to 18 years and a mean age of (16.85 ± 0.33) (six males and four females) with a mean ANB of 6.80 (0.89) and a mean mandibular length of 107.3 (2.36), who were treated by a TFBC that was installed just mesial to the tube of the maxillary first permanent molar and distal to the bracket of the lower canine for 4 months. According to the Index of Orthognathic Functional Treatment Need (IOFTN) index, the participants in both groups have grade 4 (great need for treatment) as they have excessive overjet (6-9 mm). Cone-beam computed tomography (CBCT) was taken just before installing fixed functional appliances and after the removal. The condylar volume was measured using Dolphin software. Parametric measurements were performed by the independent t-test, while non-parametric variables (percent change) were compared by the Mann-Whitney U-test.

RESULTS

On the right side, the Herbst group recorded a percent increase (median = 1.23%), while TFBC recorded a median percent decrease (-7.85%). This change is statistically significant (P = 0.008).

CONCLUSIONS

The difference in the condylar volume was significantly higher with the mini-plate anchored Herbst appliance than with the dentally anchored TFBC group.

Impact of initial lip competence on the outcome of class II functional appliances therapy

OBJECTIVES

The aim of this prospective clinical study was to evaluate the impact of initial lip position on class II functional appliance therapy.

MATERIALS AND METHODS

In total, 34 class II division 1 patients (23 females, 19 males; mean age 12.4 ± 0.9 years) that met the inclusion criteria (> ½ class II molar relationship, overjet > 6 mm, ANB > 4°, neutral or horizontal growth pattern, cervical vertebral maturation stage (CVMS) II - III, mean wear-time > 10 h/day) were consecutively divided into two groups (lip incompetence (LI); lip competence (LC)). All patients were treated with the Sander bite jumping appliance (BJA). Wear time was microelectronically measured. Lateral cephalograms were taken at the beginning (T0) and after 1 year of treatment (T1). An untreated class II group served as a control (CG). Inter-group comparisons were determined with Mann-Whitney U tests for independent samples.

RESULTS

Significant skeletal treatment effects were found in both treated groups when compared to the CG with significantly more pronounced mandibular skeletal effects in the LI than in the LC group (mandibular base length p < 0.001, composite mandibular base length p < 0.001, condylar head growth p = 0.002, co-pg p < 0.00, go-pg p = 0.003, reduction of the ANB angle p = 0.009, and Wits appraisal p < 0.001).

CONCLUSION

The more pronounced mandibular effects in the LI group were composed of the functional orthopedic effect plus harmonization of the lip competence.

CLINICAL RELEVANCE

Functional harmonization of lip incompetence with BJA enhances mandibular growth stimulation. Lip incompetence seems to impede mandibular growth and its harmonization seems to be a preventive approach.

Twin-block and mandibular anterior repositioning appliances effects in Class II malocclusion correction

INTRODUCTION

The objective of this study was to compare the cephalometric changes in Class II Division 1 malocclusion patients treated with the Twin-block (TB) and the mandibular anterior repositioning appliance (MARA).

METHODS

This retrospective study was performed with 132 lateral cephalograms of patients with Class II malocclusion divided into 3 groups: a TB group comprised 21 patients with mean initial and final ages of 10.59 and 11.97 years, respectively, treated for a mean period of 1.38 years; a MARA group comprised 21 patients with mean initial and final ages of 11.98 and 13.20 years, respectively, treated for a mean period of 1.22 years; and a control group included 24 subjects with untreated Class II malocclusion with mean initial and final ages of 10.55 and 12.01 years, respectively, observed for a mean period of 1.46 years. Cephalometric intergroup comparisons regarding the treatment changes (T2 - T1) were performed with the analysis of covariance, followed by Tukey tests.

RESULTS

Both appliances demonstrated significant restriction of the maxilla and improvement of the maxillomandibular relationship. The MARA produced a significantly greater amount of labial tipping and protrusion of the mandibular incisors than the other groups. The TB showed significant extrusion of the mandibular incisors and molars compared with MARA and control, respectively. Both treated groups reduced the overjet and overbite. The MARA presented a significantly greater reduction in the molar relationship than the other groups.

CONCLUSIONS

The appliances showed a headgear effect on the maxilla and effectively changed Class II cephalometric parameters through a combination of skeletal and dentoalveolar effects. TB showed a greater increase in LAFH. MARA promoted greater labial tipping and protrusion of the mandibular incisors.

Attractiveness of the facial profile: comparison of Class II patients treated with Twin Force® or intermaxillary elastics

Objective:

To compare the facial profile attractiveness of Class II patients treated with Twin Force^® or intermaxillary elastics.

Methods:

Sample comprised 47 Class II patients divided into two groups: G1) TWIN FORCE - 25 patients treated with fixed appliances and Twin Force^® fixed functional appliance (mean initial age was 17.91 ± 7.13 years, mean final age was 20.45 ± 7.18 years, and mean treatment time was 2.53 ± 0.83 years); G2) ELASTICS - 22 patients treated with fixed appliances and Class II intermaxillary elastics (mean initial age was 15.87 ± 5.64 years, mean final age was 18.63 ± 5.79 years and mean treatment time was 2.75 ± 0.60 years). Lateral cephalograms from pretreatment and posttreatment were used. Cephalometric variables were measured and silhouettes of facial profile were constructed and evaluated by 48 laypeople and 63 orthodontists, rating the attractiveness from 0 (most unattractive profile) to 10 (most attractive profile). Intergroup comparisons were performed with Mann-Whitney and independent t-tests.

Results:

At pretreatment, facial profile of the Twin Force^® group was less attractive than the Elastics group. Treatment with Twin Force^® or Class II elastics resulted in similar facial profile attractiveness, but the facial convexity was more reduced in the Twin Force^® group. Orthodontists were more critical than laypeople.

Conclusions:

Treatment with Twin Force^® or Class II elastics produced similar facial profile attractiveness at posttreatment. Profile attractiveness was reduced with treatment in the elastic group, and improved in the Twin Force^® group. Facial convexity was more reduced with treatment in the Twin Force^® group.

Effects of Sabbagh Universal Spring 2 appliance on cephalometric indices in patients with Class II division 1 versus division 2 malocclusions: A preliminary before-after clinical trial

BACKGROUND

Since there is no comparison between the effects of Sabbagh Universal Spring 2 (SUS2) appliance on Class II division 1 (div 1) versus Class II division 2 (div 2) patients, this preliminary study was conducted to comparatively assess, for the first time, the effects of SUS2 on 34 cephalometric indices in Class II/1 versus Class II/2 patients.

MATERIALS AND METHODS

This before-after clinical trial was conducted on 75 observations of 25 patients with Class II malocclusion, of whom 12 (9 females and 3 males) had Class II div 1 and 13 (11 females and 2 males) had Class II div 2 malocclusion diagnosed by clinical examination and cephalometric assessment. The growth level of all patients had to be CS3 according to the cervical vertebral maturation index. Lateral cephalographs were obtained before treatment (T0) and the patients underwent fixed orthodontic treatment. Lateral cephalographs were taken again (T1) and the patients received SUS2 functional appliance for 6 months. A final lateral cephalograph (T2) was then obtained. Thirty-four dentoskeletal indices were measured on lateral cephalographs, and changes in indices over time were determined and compared using repeated-measures analysis of variance, post hoc test, and t-test (α =0.05).

RESULTS

Within-group comparisons showed significant changes over time in SNB, sella nasion (SN)/occlusal plane, ANB, articular (Ar)-pogonion (Pog), L1-NB, condylion (Co)-gnathion, S-Ar/Ar-G, B-RL1, L1/nasion-point B (NB), U6-RL2, incisor mandibular plane angle, overjet, overbite, U1-RL1, and L1-RL2 (P < 0.05). The two groups were significantly different in terms of changes occurred to overjet, interincisal angle, U1/RL1, L1-NB, U1-NA, U1/NA, the Jarabak ratio, A-RL1, U1/SN, Pog-NB, and Co-A (P < 0.05).

CONCLUSION

The SUS2 showed therapeutic efficacy for both Class II div 1 and 2 patients although it more commonly caused dentoalveolar rather than skeletal changes. Our study showed no considerable difference between the two groups after using this appliance, and the difference in the Jarabak ratio indicated better long-term growth pattern of div 2 patients and its conformity with camouflage treatments (mild or moderate Class II).

Efficiency and outcome quality of Herbst-Multibracket appliance therapy in Class II:2 patients

OBJECTIVES

The aim of this retrospective investigation was to generate representative data on the efficiency and outcome quality of Class II:2 Herbst-Multibracket appliance (Herbst-MBA) treatment.

SUBJECTS AND METHODS

All Class II:2 patients who had started Herbst-MBA treatment at the study centre since 1986 were included. Study casts from before treatment, after Herbst-MBA treatment, and (if available) after ≥24 months of follow-up were evaluated using standard occlusal variables, the Peer Assessment Rating (PAR)-Index, and the Ahlgren-Scale.

RESULTS

During treatment, the pre-treatment PAR score was reduced from 23.6 ± 7.66 to 5.6 ± 3.85 (n = 192); during the follow-up period, a slight increase to 6.0 ± 3.60 occurred (n = 127). The percentage of patients who could be assigned to the PAR category 'greatly improved' was 30% after treatment and 33% after follow-up; only 1%, respectively, 2% had to be assigned to the category 'worse/no different'. The outcome ratings according to the Ahlgren-Scale revealed 20% excellent, 32% good, 46% acceptable, and 2% unsuccessful results.

LIMITATIONS

Retrospective study design with follow-up data not available from all subjects and no data from untreated controls.

CONCLUSIONS

Herbst-MBA is an efficient treatment approach in orthodontic care of Class II:2 malocclusions. High-quality results (mean/median PAR score: 5.6/5.0) with very good short-term stability (2.2 years' follow-up) were achieved. Unfortunately, no appropriate control group or groups, where other treatment approaches had been applied, exist.

Soft tissue profile changes in Angle class II patients treated with Twin Force or intermaxillary elastics-a comparison

PROPOSITION

This study aimed to compare soft tissue profile changes in Angle class II malocclusion patients treated with a Twin Force appliance (Ortho Organizers, Inc., Carlsbad, CA, USA) or class II elastics.

METHODS

The sample comprised 47 class II malocclusion patients treated orthodontically without extractions, divided into two groups. Group 1 (Twin Force): 25 patients were treated with the Twin Force, with initial and final mean ages of 17.91 and 20.45 years, respectively, and mean treatment time of 2.53 years. Group 2 (elastics): 22 patients were treated with class II elastics, with initial and final mean age of 15.87 and 18.63 years, respectively, and mean treatment time of 2.75 years. The lateral cephalograms were evaluated at the initial and final stages. Intragroup comparisons were performed with dependent t-tests and intergroup comparisons were performed with independent t-tests.

RESULTS

Treatment-related changes in the Twin Force group included reduction of facial convexity, retrusion of the upper lip, increase of the H‑Nose distance, and decrease in Sn‑H distance, indicating improvement in facial profile. In the elastics group, treatment resulted in an increase in nasolabial angle, retrusion of the upper lip, increase of the H‑Nose distance, and decrease in Sn‑H distance, indicating improvement in facial profile. The Twin Force group showed a greater reduction of the facial convexity with treatment than the elastics group.

CONCLUSIONS

Class II patients treated with the Twin Force appliance showed greater reduction in facial convexity than patients treated with class II elastics. The other soft tissue changes were similar for both groups.

Dentoskeletal and soft-tissue changes comparison between the Jasper Jumper and Twin Force Bite Corrector in Class II malocclusion patients: A retrospective study

OBJECTIVE

This retrospective study aimed to compare the dentoskeletal and soft-tissue changes in Class II malocclusion patients treated with Jasper Jumper and Twin Force Bite Corrector associated with fixed orthodontic appliances.

MATERIAL AND METHODS

The sample comprised 60 subjects divided into 3 groups. Patients with Class II malocclusion, mandibular retrusion, slight or no crowding and with no previous orthodontic treatment were eligible. Group 1 comprised 20 patients treated with the Jasper Jumper (JJ), with an initial age of 12.39 years. Group 2 comprised 20 patients treated with the Twin Force (TF), with an initial age of 11.83 years. The control group consisted of 20 untreated Class II subjects with an initial age of 12.13 years. Intergroup pretreatment comparisons were performed with One-way analysis of variance and intergroup treatment changes were compared with the Analysis of Covariance, both followed by Tukey test.

RESULTS

The TF group showed greater increase in mandibular length (6.23mm±4.64, P=0.004) than the control group (2.94mm±1.75). The mandibular incisors in the experimental groups presented significantly greater labial inclination and protrusion than the control (Md1.NB; JJ: 4.19°±2.09; TF: 4.46°±6.83; control: 1.13°±2.08, P=0.000/Md1-NB; JJ: 1.95mm±1.45; TF: 1.74mm±1.79; control: 0.31mm±0.81, P=0.000). In addition, the treated groups also showed significantly improvement of the dental relationships (Overjet; JJ: -4.05mm±4.64; TF: -3.80mm±2.12; control: 0.05mm±1.12, P=0.000/Overbite; JJ: -2.52mm±1.46; TF: -2.93mm±2.13; control: -0.63mm±1.35, P=0.000).

CONCLUSION

The Jasper Jumper and Twin Force associated to fixed appliances were effective in correcting Class II malocclusion with a combination of skeletal and dentoalveolar changes. However, the TF seems to provide more skeletal effects with greater maxillary growth restriction and mandibular length increase when compared to the JJ.

Effects of Class II division 1 malocclusion treatment with three types of fixed functional appliances

Objective:

This study aimed at comparing the dentoskeletal changes in patients with Class II division 1 malocclusion, treated with three types of fixed functional appliances.

Methods:

A sample comprising 95 patients with the same malocclusion, retrospectively selected, and divided into four groups, was used: G1 consisted of 25 patients (mean age 12.77 ± 1.24 years) treated with Jasper Jumper appliance; G2, with 25 patients (mean age 12.58 ± 1.65 years) treated with the Herbst appliance; G3, with 23 patients (mean age 12.37 ± 1.72 years) treated with the Mandibular Protraction Appliance (MPA); and a Control Group (CG) comprised of 22 untreated subjects (mean age 12.66 ± 1.12 years). Intergroup comparison was performed with ANOVA, followed by Tukey test.

Results:

The Jasper Jumper and the Herbst group showed significantly greater maxillary anterior displacement restriction. The Jasper Jumper demonstrated significantly greater increase in the mandibular plane angle, as compared to the control group. The MPA group demonstrated significantly greater palatal inclination of the maxillary incisors. Vertical development of the maxillary molars was significantly greater in the Herbst group.

Conclusions:

Despite some intergroup differences in the amount of dentoskeletal changes, the appliances were effective in correcting the main features of Class II malocclusions.

Class II Young Adult Treatment with Twin Force Bite Corrector: 10-Year Follow-up

One of the most preferred compliance free fixed functional appliances in nongrowing patients is Twin Force Bite corrector (TFBC). The aim of this case report is to evaluate the effectiveness of TFBC in the treatment of an adult Class II case. A 16-year 1-month-old boy having skeletal and dental Class II relationship was selected. Roth 0.018 × 0.025 inch slots brackets were attached; a fixed lingual arch in the mandibular dental arch and a Nance appliance in the maxillary dental arch were used to increase anchorage. The TFBC therapy used for sagittal activation and stimulation of forward mandibular growth lasted for 3 months. The post-TFBC treatment lasted 6 months and the total treatment time was 9 months. Treatment of a young adult Class II malocclusion with TFBC resulted in a Class I molar occlusion, an ideal overjet, overbite, and incisor angulation in a short time and maintained in the 10-year follow-up.

Comparison between full face and hemifacial CBCT cephalograms in clinically symmetrical patients: a pilot study

INTRODUCTION:

One of the advantages of cone-beam computed tomography (CBCT) is the possibility of obtaining images of conventional lateral cephalograms derived from partial or complete reconstruction of facial images.

OBJECTIVE:

This study aimed at comparing full face, right and left hemifacial CBCT cephalograms of orthodontic patients without clinical facial asymmetry.

METHODS:

The sample comprised nine clinically symmetrical patients who had pretreament full face CBCT. The CBCTs were reconstructed so as to obtain full face, right and left hemifacial cephalograms. Two observers, at two different times, obtained linear and angular measurements for the images using Dolphin 3D software. Dependent and independent t-tests were used to assess the reproducibility of measurements. Analysis of Variance and Kruskal-Wallis tests were used to compare the variables obtained in the CBCT derived cephalometric views.

RESULTS:

There was good reproducibility for CBCT scans and no statistically significant differences between measurements of full face, right and left hemifacial CBCT scans.

CONCLUSIONS:

Cephalometric measurements in full face, right and left hemifacial CBCT scans in clinically symmetrical patients are similar.

Stability of Class II fixed functional appliance therapy--a systematic review and meta-analysis

OBJECTIVES

To systematically search for scientific evidence concerning the stability of treatment (Tx) results achieved by means of Class II fixed functional appliance therapy and to assess possible differences between appliances.

SEARCH METHODS

An electronic search of databases and orthodontic journals was carried out (until December 2013), with supplemental hand searching. In addition to the names of all identified appliances, the term fixed functional was used in combination with each of the following search terms: long-term, post-Tx, relapse, retention, stability.

SELECTION CRITERIA

To be included in the review, the articles had to contain clear data on: Class II Tx with a fixed functional appliance (>5 patients), post-Tx period ≥ 1 year, assessment of ANB angle, Wits appraisal, molar relationship, soft-tissue profile convexity excluding the nose, overjet and/or overbite.

DATA COLLECTION AND ANALYSIS

The literature search revealed 20 scientific investigations which corresponded to only two of the 76 identified appliances (Herbst and Twin Force Bite Corrector). As only one publication was found for the Twin Force Bite Corrector, a meta-analysis could only be performed for Herbst Tx. The data were extracted, pooled and weighted according to the number of patients in each study.

RESULTS

The mean values for post-Tx relapse (percentages relative to the Tx changes) were: ANB angle 0.2 degrees (12.4 per cent), Wits appraisal 0.5mm (19.5 per cent), sagittal molar relationship 1.2mm/0.1 cusp widths (21.8 per cent /6.5 per cent); soft-tissue profile convexity excluding nose less than 0.1 degrees (1.0 per cent), overjet 1.8mm (26.2 per cent), overbite Class II:1 1.4mm (44.7 per cent), overbite Class II:2 1.0mm (22.2 per cent).

CONCLUSIONS

The scientific evidence concerning the stability of Tx results is inexistent for most fixed functional appliances for Class II correction except for Herbst appliance Tx. Even if the evidence level of most included studies is rather low, good dentoskeletal stability without clinically relevant changes was found for most variables.

Long-term surgical versus functional Class II correction: a comparison of identical twins

The purpose of this twin case comparison was to assess the short- and long-term effects of nonsurgical treatment vs orthognathic surgical treatment for Class II correction. Two identical twins (age 13 years 3 months) were treated for Class II correction where one patient was treated nonsurgically using a fixed functional appliance, while the other was treated using orthognathic mandibular advancement surgery. The patients were recalled and evaluated 5 years in retention. Comparing changes in the short and long term, surgical treatment led to superior skeletal results compared to the nonsurgical twin. However, the soft tissue profile was remarkably similar for both patients suggesting that soft tissue profile changes may not necessarily follow similar changes in the bony skeletal structures.