Functional Appliances In Class Research Articles

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.

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

Fixed Functional Appliance Therapy With and Without Skeletal Anchorage in Class II Malocclusion: A Systematic Review of Randomized Controlled Trials

Background: For its synergistic effects in producing skeletal changes as well as to lessen the proclination of the lower incisors, which is a common negative result of mandibular advancement, fixed functional appliances with skeletal anchorage have recently been used. Aim: Objective was to evaluate the skeletal and dentoalveolar effects with fixed functional appliances with and without skeletal anchorage. Methods: Electronic database search and manual search were performed up to 2021, April in four databases namely The Cochrane Library, PubMed, Lilac, and Google Scholar. RCTs that employed the use of fixed functional appliances in Class II malocclusion with and without skeletal anchoring were collected. Two co-authors independently extracted the data, and a pre-designed template was followed during the data extraction process. Data including inclusion and exclusion criteria; study design, the year of publication; age and gender of the patients; type of fixed functional device; stage of skeletal maturation; size and site of mini-implant or miniplate placement, amount of force applied in grams or Newtons; method of study outcome assessment (2D or 3D); and follow up were collected. The skeletal and dentoalveolar parameters were extracted. Results: The risk of bias was evaluated, and the SMD and 95% confidence intervals (CIs) were also calculated. Four RCTs were evaluated for qualitative and quantitative analysis. The review involved data of 179 Class II individuals. The results of a random-effects meta-analysis showed that the SNB differed significantly from the control group (SMD = 0.50 (95% CI –1.55 to –0.10)). No significant differences noted between the two groups in terms of lower incisor inclination and mandibular length changes [SMD = –0.04 (95% CI −2.06 to 1.98) and –1.33 (95% CI −3.28 to 0.62), respectively]. The studies under this were not able to provide enough data to draw any conclusions about the effects of using skeletal anchorage with FFA. Conclusion: According to the evidence that is currently available, using FFA coupled with skeletal anchorage does not appear to have any superior skeletal effects than those without skeletal anchorage.

Comparison of 2 treatment protocols using fixed functional appliances in Class II malocclusion: Treatment results and stability

The objective of this research was to compare the 2 treatment protocols including a functional mandibular advancer (FMA; Forestadent, Pforzheim, Germany) followed by multibracket appliances (MBAs) vs a Forsus device (3M Unitek, Monrovia, Calif) in combination with MBA concerning treatment outcomes and posttreatment stability. This study was conducted using lateral cephalograms of patients who were treated with MBA, which was used either after an FMA or concurrently with a Forsus device, and of patients who had untreated Class II malocclusion (control group). Each group consisted of 19 subjects in cervical stage 2 or cervical stage 3 stages according to the cervical vertebral maturation index. Cephalograms were taken for the treated groups at T1 (pretreatment), T2 (completion of the MBA treatment), and T3 (at least 2years after T2). Significant intergroup differences at the T1-T2 period were observed in favor of the FMA concerning mandibular advancement, intermaxillary relationship, and mandibular elongation. With Forsus treatment, restrained maxillary growth and a slightly improved intermaxillary relationship rebounded after treatment (P<0.05). At the end of treatment, mandibular incisor protrusion and occlusal plane rotation were greater in the Forsus group than in the FMA group (P<0.05), and maxillary incisor retroclination was significant in the Forsus group. During the posttreatment period, although no significant changes were present in the incisors' inclination, relapses of the T1-T2 improvements in overjet and overbite and the recidive of the occlusal plane rotation were significantly higher in the Forsus group. Treatment protocol including an FMA was found to be more effective with mandibular skeletal effects and was more stable with a lesser degree of relapse in overjet and overbite than the Forsus protocol.

Effects of wear time differences of removable functional appliances in class II patients: prospective MRI study of TMJ and masticatory muscle changes.

The aim of this prospective study was to evaluate the short-term effects of full-time and night-time wear of functional appliances on the temporomandibular joint (TMJ) and masticatory muscles and to compare the differences in craniofacial structures, TMJ, and masticatory muscles with magnetic resonance imaging (MRI). The study was carried out using cephalometric radiographs and MRI of 20 Class II patients who were treated with monoblock/twin-block appliances. The patients were divided into 2 groups: ten patients in Group 1 used their appliances all day, while ten patients in Group 2 were instructed to wear the appliances during sleep. After at least 6 months of uninterrupted treatment, post-treatment cephalograms and MRI were obtained for patients whose molar relationship improved by at least a half cusp width. Signal intensity ratios (SIR) of TMJ structures and morphological evaluations of masticatory muscles were done for all patients. It was found a significant increase in SIR values of the condylar process, articular disc, retrodiscal tissue, and masticatory muscles for all treatment groups. Length of the masseter and medial pterygoid muscles increased to varying degrees which left side of Group 2 was significantly increased (P < 0.05). The volume of all muscles also increased to varying degrees. The cephalometric and MRI findings of this study show that the treatment effects were similar for both wear schedules.

Effects of three types of functional appliances in class II malocclusions treatment - sagittal and vertical changes

Introduction/Objective. Class II malocclusions are sagittal malocclusions characterized by a distal relationship of posterior teeth. Depending on the underlying problem, class II can be skeletal or dentoalveolar. Class II treatment modality will depend on the cause, severity and age. Growth modification is the best treatment option in skeletal Class II growing patients. The aim of this study was to establish and compare sagittal and vertical skeletal and dental changes in patients treated with the ?M block? appliance, the Fr?nkel functional regulator and the Balters? Bionator. Methods. The sample consisted of 70 patients diagnosed with skeletal class II (ANB &gt; 4?) and mandibular retrognathism (SNB &lt; 80?). Patients were divided into 3 groups according to the type of appliance. All patients went through the standard diagnostic procedure (anamnesis, clinical and functional analysis, study model, panoramic radiograph and cephalometric analysis) and dental and skeletal age was determined. Treatment effects were analyzed on study models and cephalograms at the end of treatment. Results. All appliances led to significant mandibular anterior movement and sagittal growth, which reduced ANB values. All three groups of patients presented with neutral growth pattern, upper incisor retrusion and lower incisor protrusion at the end of treatment. Conclusion. Results of this study indicate efficacy of all three appliances in skeletal class II treatment.

Meta-analysis of the condylar position changes produced by functional appliances in class Ⅱ malocclusion

This study aimed to analyze the condylar position changes produced by functional appliances in class Ⅱ malocclusion by systematic review. Electronic search was conducted using Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals, Medline, Embase, Pubmed, and Cochrane Central Register of Controlled Trials. Studies on condylar position changes produced by functional appliances in class Ⅱ malocclusion were included. Risk of bias assessment and data extraction of included studies were conducted by two reviewers independently. The meta-analysis was carried out using Revman 5.1. Six studies were included (five high quality and one low quality). The condylar position showed no changes after Herbst treatment. The condylar posterior space after Twin-block treatment averagely increased by 0.31 mm (P<0.000 01), whereas the condylar anterior space averagely reduced by 0.32 mm (P<0.000 01). Twin-block appliance enables forward movement of the condylar position. This result contributes to the correction of class Ⅱ malocclusion.

Thin-plate spline analysis of mandibular shape changes induced by functional appliances in Class II malocclusion : A long-term evaluation.

The purpose of this work was to evaluate the long-term morphological mandibular changes induced by functional treatment of Class II malocclusion with mandibular retrusion. Forty patients (20 females, 20 males) with Class II malocclusion consecutively treated with either a Bionator or an Activator followed by fixed appliances were compared with a control group of 40 subjects (19 females, 21 males) with untreated Class II malocclusion. Lateral cephalograms were available at the start of treatment (T1, mean age 9.9years), at the end of treatment with functional appliances (T2, mean age 12.2years), and for long-term follow-up (T3, mean age 18.3years). Mandibular shape changes were analyzed on lateral cephalograms of the subjects in both groups via thin-plate spline (TPS) analysis. Shape differences were statistically analyzed by conducting permutation tests on Goodall F statistics. In the long term, both the treated and control groups exhibited significant longitudinal mandibular shape changes characterized by upward and forward dislocation of point Co associated with a vertical extension in the gonial region and backward dislocation of point B. Functional appliances induced mandible's significant posterior morphogenetic rotation over the short term. The treated and control groups demonstrated similar mandibular shape over the long term.

Effectiveness of orthodontic treatment with functional appliances on maxillary growth in the short term: A systematic review and meta-analysis.

The aim of this systematic review was to evaluate the treatment effects on maxillary growth of removable functional appliances that advance the mandible to a more forward position in patients with Class II malocclusion. Sixteen electronic databases and reference lists of studies were searched up to April 2015. Only randomized clinical trials and prospective controlled clinical trials investigating Class II growing patients treated with removable functional appliances were included. Two authors independently accomplished study selection, data extraction, and risk of bias assessment. All pooled analyses of data were based on random-effects models. Statistical heterogeneity was evaluated. In total, 14 studies were included (5 randomized clinical trials, 9 prospective controlled clinical trials) that collected data from 765 patients (405treated, 360 untreated controls). The mean differences in treatment effect of functional appliances, relative to the untreated controls, were -0.61° per year (95% CI, -0.69° to -0.25°) for SNA angle, -0.61mm per year (95% CI, -0.90 to -0.32mm) for anterior maxillary displacement, and+0.07° per year (95% CI, -0.17° to+0.32°) for maxillary plane rotation. Removable functional appliances in Class II growing patients have a slight inhibitory effect on the sagittal growth of the maxilla in the short term, but they do not seem to affect rotation of the maxillary plane.

Treatment Effects of Removable Functional Appliances in Pre-Pubertal and Pubertal Class II Patients: A Systematic Review and Meta-Analysis of Controlled Studies.

BackgroundTreatment effects of removable functional appliances in Class II malocclusion patients according to the pre-pubertal or pubertal growth phase has yet to be clarified.ObjectivesTo assess and compare skeletal and dentoalveolar effects of removable functional appliances in Class II malocclusion treatment between pre-pubertal and pubertal patients.Search methodsLiterature survey using the Medline, SCOPUS, LILACS and SciELO databases, the Cochrane Library from inception to May 31, 2015. A manual search was also performed.Selection criteriaRandomised (RCTs) or controlled clinical trials with a matched untreated control group. No restrictions were set regarding the type of removable appliance whenever used alone.Data collection and analysisFor the meta-analysis, cephalometric parameters on the supplementary mandibular growth were the main outcomes, with other cephalometric parameters considered as secondary outcomes. Risk of bias in individual and across studies were evaluated along with sensitivity analysis for low quality studies. Mean differences and 95% confidence intervals for annualised changes were computed according to a random model. Differences between pre-pubertal and pubertal patients were assessed by subgroup analyses. GRADE assessment was performed for the main outcomes.ResultsTwelve articles (but only 3 RCTs) were included accounting for 8 pre-pubertal and 7 pubertal groups. Overall supplementary total mandibular length and mandibular ramus height were 0.95 mm (0.38, 1.51) and 0.00 mm (-0.52, 0.53) for pre-pubertal patients and 2.91 mm (2.04, 3.79) and 2.18 mm (1.51, 2.86) for pubertal patients, respectively. The subgroup difference was significant for both parameters (p<0.001). No maxillary growth restrain or increase in facial divergence was seen in either subgroup. The GRADE assessment was low for the pre-pubertal patients, and generally moderate for the pubertal patients.ConclusionsTaking into account the limited quality and heterogeneity of the included studies, functional treatment by removable appliances may be effective in treating Class II malocclusion with clinically relevant skeletal effects if performed during the pubertal growth phase.

Re: response to: Long-term skeletal and dental effects and treatment timing for functional appliances in Class II malocclusion. The Angle Orthodontist 2013(2) 334-340

Because a major reason for orthodontic treatment is to overcome psychosocial difficulties related to facial and dental appearance and enhance social well-being, the evaluation of dental and facial esthetics has become an important part of the clinical examination. Whether a face is considered beautiful is affected substantially by cultural and ethnic factors, but whatever the culture, a severely disproportionate face becomes a psychosocial problem. Differences in facial types and body types obviously must be taken into account when facial proportions are assessed, and variations from the average ratios can be compatible with good facial esthetics. An important point, however, is to avoid treatment outcomes that would change the ratios in the wrong direction, as for example, treatment with interarch elastics that could rotate the mandible downward in a patient whose face already is too long for its width. As for the long-term vertical skeletal effects produced by functional appliances, our study found that treatment did not induce any significant increase in vertical skeletal relationships, as assessed either by the inclination of the palatal plane to Frankfort horizontal or with the inclination of the mandibular plane to the Frankfort horizontal and to the palatal plane. In the Discussion we reported that ‘‘A significant increase in lower anterior facial height in the treated group was associated with a significant increase in the height of the mandibular ramus in the long term. Adequate control of vertical skeletal relationships in the long term was achieved through a good balance between posterior and anterior facial height increases.’’ The case cited by Dr. Mew and published on the Journal of Clinical Orthodontics was included in an unpublished study in which the aesthetics of both the teeth and face were rated by lay and orthodontic judges. We do not know if the evaluation was performed on the comparisons of the photos taken before and after treatment. The main esthetic issue of the face of the specific clinical case can be related to the large nasolabial angle rather than to the increase in the lower anterior facial height that is compatible with the normal vertical growth of the face. However, we certainly look forward to seeing the published data of the study quoted by Dr. Mew.

Re: Long-term skeletal and dental effects and treatment timing for functional appliances in Class II malocclusion. The Angle Orthodontist 2013(2) 334–340

What do patients want?Patient's wishes are simple: an attractive face and smile achieved without discomfort or damage, which lasts a lifetime. Is this always achievable? If not, how should we balance the priorities?One of the problems is that we have become so involved in aligning the teeth that we sometimes fail to look at their owner. In last month's journal, Franchi, Pavoni, Faltin, McNamara and Cozza1 showed that functional appliances can achieve “a significant long-term elongation of the mandible” but also “an increase in lower anterior facial height”. This confirms numerous previous findings that most treatment, fixed or functional increases vertical growth.2–8 Other research has suggested that longer faces are less attractive.9This point can be illustrated with an example taken with permission from the Journal of Clinical Orthodontics (Figure 1).10 This case was treated by a fixed functional as part of a case presentation. It was later included in an unpublished study in which the aesthetics of both the teeth and face were rated by lay and orthodontic judges. Six orthodontic judges ranked this result as 12th out of 32 patients, but 6 lay judges placed it 32nd. The teeth seem to be near ideal so what is the problem?The public seem exceptionally sensitive to increases in lower anterior facial height and yet a glance through treated cases shows that this is common side effect of orthodontics. How should benefits be balanced against risks and, of more importance, who should make that choice? We need to remember that our duty is to the public.

Long-term skeletal and dental effects and treatment timing for functional appliances in Class II malocclusion

To analyze the long-term skeletal and dentoalveolar effects and to evaluate treatment timing of Class II treatment with functional appliances followed by fixed appliances. A group of 40 patients (22 females and 18 males) with Class II malocclusion consecutively treated either with a Bionator or an Activator followed by fixed appliances was compared with a control group of 20 subjects (9 females and 11 males) with untreated Class II malocclusion. Lateral cephalograms were available at the start of treatment (mean age 10 years), end of treatment with functional appliances (mean age 12 years), and long-term observation (mean age 18.6 years). The treated sample also was divided into two groups according to skeletal maturity. The early-treatment group was composed of 20 subjects (12 females and 8 males) treated before puberty, while the late-treatment group included 20 subjects (10 females and 10 males) treated at puberty. Statistical comparisons were performed with analysis of variance followed by Tukey's post hoc tests. Significant long-term mandibular changes (Co-Gn) in the treated group (3.6 mm over the controls) were associated with improvements in the skeletal sagittal intermaxillary relationship, overjet, and molar relationship (∼3.0-3.5 mm). Treatment during the pubertal peak was able to produce significantly greater increases in total mandibular length (4.3 mm) and mandibular ramus height (3.1 mm) associated with a significant advancement of the bony chin (3.9 mm) when compared with treatment before puberty. Treatment of Class II malocclusion with functional appliances appears to be more effective at puberty.

Oropharyngeal airway dimensions after treatment with functional appliances in class II retrognathic children

Class II skeletal malocclusion and respiratory disorders owing to the obstruction of the upper airway at early growth stages have been correlated. The retro/micrognathism can be treated with functional appliances. However, the effects of an early functional orthopedic treatment on the airway dimensions have not been evaluated before the growth peak. Therefore, the objective of this study was to evaluate the changes in the airway dimensions of class II retrognathic children who received treatment with either Klammt or Bionator on a pre-pubertal stage. The sample consisted of 50 lateral cephalograms of class II retrognathic patients in a pre-puberal stage, before and after the use of a Klammt or Bionator II treatment for 1 year. The data were evaluated by Student's t-test or Mann-Whitney test, and significance was set at 5% (P < 0·05). When the measurements before and after treatment were compared, a statistically significant increase in the airway dimensions was found at the space where the adenoid tissue was located. The only airway dimensions that increased after treatment with functional appliances were the ones located at the nasopharynx. The adenoid tissue is still in the peak of growing at the ages of the subjects included in this study. However, the measurements along the nasopharynx increased when compared with the initial ones. Still, similar retrospective and prospective studies are needed at older stages.

Soft tissue changes with fixed functional appliances in Class II division 1.

To evaluate facial soft tissue changes after the use of fixed functional appliances in Class II division 1 malocclusion cases using a systematic review of the literature. Several electronic databases (PubMed, Medline, Medline In-Process & Other Non-Indexed Citations, Cochrane Database, Embase, Web of Sciences, and Lilacs) were searched with the help of a senior Health Sciences librarian. Abstracts that appeared to fulfill the initial selection criteria were selected by consensus. The original articles were then retrieved. Their references were also hand-searched for possible missing articles. Clinical trials assessing facial soft tissue changes with the use of fixed functional appliances without any surgical intervention or syndromic characteristics were considered. A comparable untreated control group was required to factor out normal growth changes. Four articles using Herbst and one using Jasper Jumper fulfilled the selection criteria. An individual analysis of these articles was made and some methodological flaws were identified. Although fixed functional appliances produce some significant statistical changes in the soft tissue profile, the magnitude of the changes may not be perceived as clinically significant. The conclusions from this systematic review should be considered with caution because only a secondary level of evidence was found. Long-term double-blinded prospective randomized clinical trials are needed. Three-dimensional quantification of the soft tissue changes is required to overcome current limitations in our understanding of the soft tissue changes obtained with the use of fixed functional appliances.

Functional Appliances Stimulate Clinically Significant Elongation of the Mandible in Class II Subjects

Mandibular Changes Produced by Functional Appliances in Class II Malocclusion: A Systematic Review. Cozza P, Baccetti T, Franchi L, De Toffol L, McNamara JA, Jr. Am J Orthod Dentofacial Orthop 2006;129(5):599-e12. 2a Does the mandible grow more in Class II subjects treated with functional appliances than in untreated Class II subjects? Is the average effect of functional appliances on mandibular length clinically significant? Which functional appliances are more efficient? Information not available Systematic review

Analysis of activator treatment changes

Abstract The effects of functional appliance treatment have been reported in numerous studies in the literature with great variability in the findings. It is generally agreed that they can be used successfully to treat Class II malocclusions in growing and cooperative patients. However, there is a lack' of consensus regarding the relative orthodontic and orthopedic correction obtained by functional appliances in Class II correction. Lateral cephalometric radiographs from a sample (n=36) of patients who had undergone a phase of treatment with activator appliances were measured and analysed for changes using a modified version of the method described by Johnston (Hashim and Godfrey 1990). In this method, the treatment changes were broken down into: tooth movement relative to basal bone; and the translatory growth of the jaws, both with respect to the cranial base and to each other. The results show that the treatment effects were mainly dentoalveolar. There was a slight orthopedic effect on the maxilla, but no significant mandibular growth was observed, above that which can be expected from normal growth.