title: Inadvertent tooth movement with fixed lingual retainers.
abstract: Fixed retainers are effective in maintaining the alignment of the anterior teeth more than 90% of the time, but they can produce inadvertent tooth movement that in the most severe instances requires orthodontic retreatment managed with a periodontist. This is different from relapse into crowding when a fixed retainer is lost. These problems arise when the retainer breaks but remains bonded to some or all teeth, or when an intact retainer is distorted by function or was not passive when bonded. In both instances, torque of the affected teeth is the predominant outcome. A fixed retainer made with dead soft wire is the least likely to create torque problems but is the most likely to break. Highly flexible twist wires bonded to all the teeth appear to be the most likely to produce inadvertent tooth movement, but this also can occur with stiffer wires bonded only to the canines. Orthodontists, general dentists, and patients should be aware of possible problems with fixed retainers, especially those with all teeth bonded, because the patient might not notice partial debonding. Regular observations of patients wearing fixed retainers by orthodontists in the short term and family dentists in the long term are needed.
authors.affiliation: Private practice, Marietta and Suwanee, Ga, and Abu Dhabi, United Arab Emirates. Electronic address: str8tth@me.com.
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Shaughnessy
authors.affiliation: Emeritus professor, Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC.
authors.forename: William R
authors.initials: WR
authors.lastname: Proffit
authors.affiliation: Private practice, Dubai and Abu Dhabi, United Arab Emirates.
authors.forename: Said A
authors.initials: SA
authors.lastname: Samara
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000209:etiology; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding / Q000009:adverse effects / Q000379:methods; D004868:Equipment Failure; D005260:Female; D005889:Gingival Recession / Q000209:etiology; D006801:Humans; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers / Q000009:adverse effects*; D009969:Orthodontic Wires / Q000009:adverse effects*; D017622:Periodontal Attachment Loss / Q000209:etiology; D018583:Pliability; D019233:Retreatment; D013193:Stainless Steel / Q000737:chemistry; D013232:Steel / Q000737:chemistry; D013314:Stress, Mechanical; D014087:Tooth Movement Techniques / Q000009:adverse effects; D019415:Torque
chemical_list: D003722:Dental Alloys; D013193:Stainless Steel; D013232:Steel