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Title Treatment of Class II Malocclusion is Equally Effective with a Fixed Functional Appliance or Removable Appliance
Clinical Question For patients with a Class II malocclusion, is treatment with a fixed functional appliance more effective at correcting jaw discrepancy as compared to a removable functional appliance?
Clinical Bottom Line For patients with Class II malocclusion, there is no difference in clinical results when treated with fixed functional appliance or removable functional appliance. This is supported by a systematic review that included two randomized controlled trials and two clinical controlled trials, in which overjet was successfully treated in trial subjects by both modalities. Fixed functional appliances and removable functional appliances can effectively treat Class II malocclusion.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 26628629Pacha, 2016297 patients in 4 included studiesSystematic review of randomized and nonrandomized trials
Key resultsPatients in the included studies were aged 16 years old or younger with Class II malocclusion and at least 5 mm overjet. Both fixed and removable appliances successfully treated the overjet and corrected it to within normal limits, observed dentally, clinically, and with soft tissue profile. Measurements for anteroposterior changes used in all reviewed studies included A-point with occlusal plane perpendicular, pogonion with occlusal plane perpendicular, and the skeletal measurement between these points. Data was reported as mean differences with either standard deviations or 95% confidence intervals. Secondary outcomes, related to patient experience and to the duration of functional phase treatment, were reported as odds ratios with 95% confidence intervals. Each study concluded that treatment time was increased with a removable functional appliance when compared to a fixed functional appliance. No meta-analysis was performed due to the high risk of bias for 3 of the 4 included studies.
Evidence Search (((((class II malocclusion) AND (orthodontic fixed functional appliance)) AND (orthodontic removable appliance)) AND (class II malocclusion therapy)) AND (orthodontic functional appliance)) AND (Angle Class II)
Comments on
The Evidence
Four studies were reviewed – two randomized clinical trials (RCTs) and two controlled clinical trials (CCTs). There are limitations present in the included studies due to the lack of blinding of operators and participants, which would be impractical in this type of orthodontic therapy. Only one study mentioned blinding of assessors. One study did report unbalanced dropout of participants, which presents a high risk of attrition bias. There were no untreated control groups in any of the four studies. Heterogeneity exists among the four studies due to different measurement outcomes (only four measurements were consistent in each study out of 22 measurement outcomes listed). The type of intervention in the four studies was not standardized; although mechanics and appliance design are similar among appliances, various fixed (F) and removable (R) appliances were used in these studies: Herbst(F) and Twin Block Appliance(R), Activator(R) to the Forsus(F) and the Twin Force Bite Corrector(F). “A meta-analysis was not possible due to both clinical and statistical heterogeneity, precluding quality of evidence assessment (GRADE) and further statistical synthesis.” Although all studies reported positive outcomes in treating Class II malocclusion, further studies are needed to establish successful treatment cephalometrically and in regard to the patient experience. Standardized measurements would aid in defining successful treatment outcomes.
Applicability The results demonstrate that modern Class II appliances successfully treat malocclusion. Since the patient base using these appliances is in a phase of maturation, compliance with removable fixed appliances is a concern, as is the number of office visits required. The compliance and treatment time are critical in terms of correcting growth discrepancies before growth is complete; a successful treatment outcome in the least amount of time is a value important to both orthodontists and patients.
Specialty/Discipline (Orthodontics)
Keywords Class II Malocclusion treatment, Orthodontic functional appliance, orthodontic removable appliance, orthodontic fixed appliance, Herbst, Forsus, Twin Block Appliance
ID# 3467
Date of submission: 11/12/2021spacer
Author Madison Hauritz
Co-author(s) Dakota Miller
Co-author(s) e-mail MillerD8@livemail.uthscsa.edu
Faculty mentor/Co-author Ravikumar Anthony
Faculty mentor/Co-author e-mail ANTHONYR@uthscsa.edu
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