Interventions for managing relapse of the lower front teeth after orthodontic treatment

Abstract

Background: Orthodontic relapse can be defined as the tendency for teeth to return to their pre-treatment position, and this occurs especially in lower front teeth (lower canines and lower incisors). Retention, to maintain the position of corrected teeth, has become one of the most important phases of orthodontic treatment. However, 10 years after the completion of orthodontic treatment, only 30% to 50% of orthodontic patients effectively retain the satisfactory alignment initially obtained. After 20 years, satisfactory alignment reduces to 10%. When relapse occurs, simple effective strategies are required to effectively manage the problem. The periodontal, physiological or psychological conditions may be different from those before orthodontic treatment, so re-treatment methods may also need to be different.

Objectives: To assess the effects of interventions used to manage relapse of the lower front teeth after first fixed orthodontic treatment.

Search methods: The following electronic databases were searched: the Cochrane Oral Health Group Trials Register (to 9 November 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 10), MEDLINE via OVID (1950 to 9 November 2012), EMBASE via OVID (1980 to 9 November 2012). There were no restrictions regarding language or date of publication. A thorough handsearch was done in relation to the following journals: American Journal of Orthodontics and Dentofacial Orthopedics (1970 to 9 November 2012), Angle Orthodontist (1978 to 9 November 2012), European Journal of Orthodontics (1979 to 9 November 2012), Journal of Orthodontics (1978 to 9 November 2012), Chinese Journal of Stomatology (1953 to 9 November 2012), West China Journal of Stomatology (1983 to 9 November 2012), Chinese Journal of Dental Materials and Devices (1992 to 9 November 2012) and Chinese Journal of Orthodontics (1994 to 9 November 2012).

Selection criteria: We would have included randomised controlled trials (RCTs) which compared any of the following: fixed options (including labial braces, lingual braces and fixed lingual wire), removable options (including Hawley's retainer with active components such as Hawley's retainer with spring elastomeric module, Bloore removable aligner and any other modifications on the Hawley's retainer to correct the lower front teeth, and invisible removable aligners such as Invisalign and Clearstep) and no active treatment for the management of relapsed lower front teeth after orthodontic treatment. We excluded RCTs of participants with craniofacial deformities/syndromes or serious skeletal deformities who received prior surgical/surgical orthodontic treatment.

Data collection and analysis: Two review authors, independently and in duplicate, assessed the results of the searches to identify studies for inclusion. The Cochrane Collaboration statistical guidelines were to be followed for data synthesis.

Main results: We did not identify any RCTs which met the inclusion criteria for this review.

Authors' conclusions: This review has revealed that there was no evidence from RCTs to show that one intervention was superior to another to manage the relapse of the alignment of lower front teeth using any method or index, aesthetic assessment by participants and practitioners, treatment time, patient's discomfort, quality of life, cost-benefit considerations, stability of the correction, and side effects including pain, gingivitis, enamel decalcification and root resorption. There is an urgent need for RCTs in this area to identify the most effective and safe method for managing the relapse of alignment of the lower front teeth.

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Little's irregularity index (= A + B + C + D + E). This photograph was taken by the review authors, in reference to Little 1975.

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Labial braces. This photograph was taken by the review authors.

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Lingual braces. This photograph was taken by the review authors.

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Fixed lingual wire. Clinical application of fixed lingual flexible wire to re‐correct lower front teeth in a 31‐year‐old male. A: Front view after placing the fixed lingual flexible wire. B: Occlusal surface view after placing the fixed lingual flexible wire. These photographs were taken by the review authors, in reference to Liou 2001.

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Hawley's retainer with spring elastomeric module. Figure depicts a 29‐year‐old female, whose right central incisor is rotated mesial‐in and right lateral incisor is labial‐lingual malpositioned. The picture shows the occlusal review after placing the Hawley's retainer with spring elastomeric module. Adjustment of the outer bow of the retainer allows facial movement of the incisors and assists in the rotation and alignment. This photograph was taken by the review authors, in reference to Cureton 1996.

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Bloore removable aligner. Clinical application of Bloore removable aligner to treat the relapse of lower front teeth. This figure shows Bloore removable aligner prior to activation of 0.026 inch eyelet arm springs. A: Front view after placing the Bloore Removable Aligner. B: Occlusal surface view after placing the Bloore removable aligner. These photographs were taken by the review authors, in reference to Bloore 1998.

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Invisalign. Clinical application of Invisalign to re‐retreat the mandibular anterior crowding teeth. As figures show this appliance is invisible. A: Front view after placing the Invisalign. B: Occlusal surface view after placing the Invisalign. These photographs were taken by the review authors.

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Study flow diagram