Title Removal of Anterior Lingual Retention Causes Relapse in Post Orthodontic Treated Patients
Clinical Question In post-orthodontic treated patients that have a fixed lingual retainer, is there a significant difference in anterior tooth movement if the retainer is removed versus the retainer remaining on the teeth?
Clinical Bottom Line For patients that have their permanent lingual bar (or any retention) removed after orthodontic treatment is completed, relapse and anterior crowding can be expected.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
18174074Booth/2008n=60 post-orthodontic treatment with lingual canine-canine bonded retainer.Prospective Cohort Study
Key resultsFor this study an irregularity index score >2 mm was considered to be relapse toward crowding. Of the 45 patients that still had lingual bonded retainers, 20 years after it was put on, only 1 patient had a irregularity index score >2 mm. Of the 15 that no longer had lingual bonded retainers the mean irregularity score was 3.3 +/- 1.55 mm with a p value <.0001.
3163221Little/1988N=31, adult patients post- retentionProspective Cohort Study
Key resultsThis study looks at the irregularity index 10 years post-retention and 20 years post retention. The mean irregularity index 10 years post-retention was 5.25 mm (range 1.96- 10.14 mm). 20 years post-retention had a mean irregularity index of 6.02 mm (range 2.38-11.48).
Evidence Search follow-up[All Fields] AND ("patients"[MeSH Terms] OR "patients"[All Fields]) AND permanently[All Fields] AND bonded[All Fields] AND ("mandible"[MeSH Terms] OR "mandible"[All Fields] OR "mandibular"[All Fields]) AND canine-to-canine[All Fields] AND retainers.[All Fields] ("Changes"[Journal] OR "changes"[All Fields]) AND ("mandible"[MeSH Terms] OR "mandible"[All Fields] OR "mandibular"[All Fields]) AND anterior[All Fields] AND alignment[All Fields] AND 10[All Fields] AND 20[All Fields] AND years[All Fields] AND postretention[All Fields]
Comments on
The Evidence
Validity: Both cohort studies had similar groups at the start who were treated the in the same manner, had adequate follow up with acceptable compliance rates, and recall bias was unlikely. There were also not any competing interests. The studies followed their patients for an extended amount of time. Perspective: Based on the cohort studies permanent retention (permanent lingual retainer) seems like a reasonable way to prevent relapse toward crowding. If retention is removed the teeth will relapse toward crowding.
Applicability Patients with permanent lingual retainers are representative of patients that would be seen in a general practice. To ease hygiene for patients some dentists and hygienists might recommend removing fixed lingual retainers. This could cause potential harm to the patient if a dentist were to remove a fixed lingual retainer and not replace it with removable retention because the teeth will relapse toward crowding. The crowding could cause occlusal discrepancies and possibly require the patient to enter orthodontic treatment again.
Specialty (General Dentistry) (Orthodontics)
Keywords Fixed Lingual Retainer, Retention, Orthodontics, Relapse
ID# 3014
Date of submission 03/10/2016
E-mail vancura@livemail.uthscsa.edu
Author Patrick VanCura
Co-author(s) e-mail
Faculty mentor Mark Littlestar, DDS
Faculty mentor e-mail littlestarm@uthscsa.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available