The use of flexible multistrand spiral wire for fixed retainers was first advocated by Zachrisson in the 1980s (Figure 1). The two basic designs of lingual bonded retainers are a flexible wire bonded to each tooth in the segment, or a more rigid wire bonded only on the canines.
A transfer tray fashioned out of vinyl polysiloxane putty can facilitate access and ease of placement on the teeth, and is highly recommended so it is passively placed. Some can be fabricated directly in the mouth, if desired, while others are best fabricated indirectly on a stone model. Several types of fixed retainers are available. Self-care is also important, and use of interdental cleaning aids is advised to ensure adequate oral hygiene. 14,15 Fixed retainers therefore require long-term maintenance and follow-up with either the orthodontist or general dentist. While rare, other significant issues include torqueing of teeth (leading to tooth displacement), gingival recession and bone loss.
12,13 In addition, detachment of the retainer from the tooth surface can cause teeth to shift. For example, there can be areas of plaque accumulation - although studies do not report an increase in interproximal caries or periodontal disease. Potential problems and complications can occur with fixed retainers, however. Most orthodontists recommend removable retainers for a minimum of two years, and even up to five years or longer.įixed retainers may be utilized unless there are contraindications, which might include active caries or periodontal disease, poor oral hygiene, anterior deep bite for maxillary retention, atypical lingual tooth morphology, or incomplete treatment. 7–11 Choosing fixed retainers for the lower dental arch is most popular, with increasing use of upper vacuum-formed retainers - with or without fixed bonding to the maxillary incisors. Surveys in the United States and elsewhere have identified trends in the selection and duration for retainer wear. In recent times, fixed retention has been an increasingly popular approach in orthodontics. Stainless steel wire bonded to the maxillary incisors.
Clinical view of 0.016×0.025-inch multistrand 5,6 These include diastemas, anterior crowding, rotated teeth, maintenance of lower incisor position during late growth, maintenance of pontic or implant space, inter-canine width expansion, adult treatment, and where patient compliance is questionable (especially over long term). While the type and term of a retention regimen may prove controversial, it is generally accepted in orthodontics that certain situations are best addressed by fixed retention. Retention requirements are determined by the characteristics of the original malocclusion and effects of orthodontic treatment. The method of retention is best selected at the outset of treatment and incorporated in the treatment plan for that particular case. 4Īmong the many suggested factors that influence stability, the primary three are: (1) periodontal ligament fibers and gingival fibers affected by orthodontic tooth movement, which require time for reorganization when the appliances are removed (2) late mandibular growth and (3) physiologic imbalance of local extrinsic forces, such as lip, cheek and tongue pressures acting on the corrected dentition so the teeth may be in an inherently unstable position. It is considered inevitable that for the majority of treated cases, some degree of relapse will occur, either with or without retention. In orthodontics, planning for retention begins with proper diagnosis, treatment planning, sound biomechanical principles, and placing the teeth in optimal functional occlusion. 1,2 In 1934, Oppenheim 3 stated “Retention is a problem in orthodontic treatment, in fact, it is the problem.” Retention is the final phase of active orthodontic therapy, and the clinical goal is to maintain teeth in a healthy, functional and esthetic position. T he importance of retention after orthodontic treatment is well recognized.
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