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Title Single-Phase Treatment of Class II Malocclusion Patients During Adolescence Results in More Efficient Treatment and Better Clinical Outcomes
Clinical Question In children with class II malocclusions, does early two-phase orthodontic treatment produce a better clinical outcome compared to single-phase treatment in late adolescence?
Clinical Bottom Line For patients with class II malocclusions, single phase treatment during adolescence results in more efficient treatment times and better clinical outcomes compared with patients treated with two phase orthodontic treatment.
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) 29534303Batista/201827 studies/1251 participants presenting with prominent upper front teeth (Class II Division 1 malocclusion) ranging from 7-15 years oldCochrane Review of RCTs
Key resultsModerate evidence indicates that early phase treatment in patients with class II malocclusions reduces incidence of incisal trauma significantly (OR 0.56, 95% CI 0.33 to 0.95), but there are no other advantages to a two-phase treatment. After both the single-phase and two-phase groups concluded comprehensive treatment, no difference was observed in final overjet or ANB angles (MD 0.21, 95% CI -0.10 to 0.51, P = 0.18) in the studies comparing early and late treatment. Overall quality of evidence in this review was determined to be low due to only two of the included trials being at low risk of bias. The review also included single-phase and two-phase studies, the latter of which being much more prone to bias.
#2) 15179390Tulloch/2004137 participants2-Phased parallel Randomized Controlled Trial
Key resultsKey Results – Two phase treatment of most young patients with class II malocclusion and normal face height is less efficient and not more effective than single stage treatment in adolescence. Time in fixed appliance for the group that completed phase 1 treatment and the control group only receiving comprehensive treatment: the average is almost identical - 26.7 months vs 26.2 respectively (P = 0.20)
#3) 2111647King/1990N/ALiterature Review
Key resultsEarly treatment of class II malocclusions should include patient considerations such as increased treatment time, financial burden, patient burnout, and loss of compliance. Skeletal corrections achieved during phase 1 treatment with an aim to reduce the need for dentoalveolar compensation during phase 2 treatment has not been clarified. The author of the literature review is skeptical of the increased popularity of early treatment. The study recommends solving this clinical question with “carefully controlled prospective studies”, as the available literature had deficient methods due to being retrospective, lacking control groups and only analyzing successful cases.
Evidence Search Treatment timing of class II malocclusions, Class II malocclusion two-phase treatment
Comments on
The Evidence
While Batista’s Cochrane review directly addresses early treatment vs. treatment during adolescence, 15 of the 27 studies included were at high risk of bias with selection, detection, and reporting bias. The 3 studies directly comparing the two treatment modalities may be of limited validity due to high degree of heterogeneity (I2=62%). The PICO question was clearly stated in the study, with mesh terms of “Child 6-12 years, adolescent 13-18 years, Angle Class II malocclusion, early treatment, and delayed treatment” clearly stated as a reference for the search. Inclusion criteria of RCT clearly stated in study as “trials of orthodontic treatments to correct prominent upper front teeth (Class II malocclusion) in children and adolescents…that compared early treatment in children (two‐phase) with any type of orthodontic braces (removable, fixed, functional) or head‐braces versus late treatment in adolescents”. Trials with cleft lip patients, syndromes, craniofacial deformities, and patients with prior orthodontic treatment were excluded. Heterogeneity in the studies were directly addressed by analyzing the trials according to the functional appliances used. Tulloch’s RCT clearly delineated the criteria for patients enrolled in the study (7 mm overjet, mixed dentition, growth potential remaining, no prior orthodontic therapy) but were assigned to treatment groups by block randomization rather than centralized computer assisted randomization. The study reported an 82% retention rate going into phase two of treatment, a significant loss in participants. Although no mention of blinding was seen in the study, evaluation of equivalence for the 4 groups treated by a different clinician was conducted. Chi square test was used for proportion of patients in early treatment group and sex, and ANOVA for skeletal, dental and inter-jaw characteristics. Although both groups were treated equally, it is impossible to account for differences in treatment due to different assigned clinicians. King’s literature review failed to answer any clinical questions concerning treatment timing of class II malocclusions but did bring to light gaps in the literature on whether early treatment offer significant improvement, are any growth modification therapies in early treatment maintained into adolescence, and if the benefit of early treatment is worth the cost/risks.
Applicability In orthodontic practice, class II malocclusions account for 15% of all treated cases. Although clinicians must use their best judgement on who would benefit from early treatment, taking into account risk of trauma and psychosocial factors, evidence shows single phase treatment in adolescence leads to a clinically equivalent results in a shorter treatment time.
Specialty/Discipline (Orthodontics) (Pediatric Dentistry)
Keywords Class II malocclusion treatment timing, two-phase vs. single phase treatment
ID# 3541
Date of submission: 10/19/2023spacer
E-mail ojedaj1@livemail.uthscsa.edu
Author Jesus Ojeda, DDS
Co-author(s) James Otani, DDS
Co-author(s) e-mail otani@livemail.uthscsa.edu
Faculty mentor/Co-author Maria Karakousoglou, DDS
Faculty mentor/Co-author e-mail karakousoglo@uthscsa.edu
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