title: Lingual vs. labial fixed orthodontic appliances: systematic review and meta-analysis of treatment effects.
abstract: The aim of this systematic review was to compare the therapeutic and adverse effects of lingual and labial orthodontic fixed appliances from clinical trials on human patients in an evidence-based manner. Randomized and prospective non-randomized clinical trials comparing lingual and labial appliances were included. Risk of bias within and across studies was assessed using the Cochrane tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random-effects meta-analyses were conducted, followed by subgroup and sensitivity analyses. Six electronic databases were searched from inception to July 2015, without limitations. A total of 13 papers pertaining to 11 clinical trials were included with a total of 407 (34% male/66% female) patients. Compared with labial appliances, lingual appliances were associated with increased overall oral discomfort, increased speech impediment (measured using auditory analysis), worse speech performance assessed by laypersons, increased eating difficulty, and decreased intermolar width. On the other hand, lingual appliances were associated with increased intercanine width and significantly decreased anchorage loss of the maxillary first molar during space closure. Based on existing trials, there is insufficient evidence to make robust recommendations for lingual fixed orthodontic appliances regarding their therapeutic or adverse effects, as the quality of evidence was low.
authors.affiliation: Department of Orthodontics, School of Dentistry, University of Bonn, Bonn, Germany.|Department of Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany.
authors.forename: Spyridon N
authors.identifier: http://orcid.org/0000-0003-1968-3326
authors.initials: SN
authors.lastname: Papageorgiou
authors.affiliation: Department of Orthodontics, School of Dentistry, University of Bonn, Bonn, Germany.
authors.forename: Lina
authors.initials: L
authors.lastname: Gölz
authors.affiliation: Department of Orthodontics, School of Dentistry, University of Bonn, Bonn, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Jäger
authors.affiliation: Clinic of Orthodontics and Paediatric Dentistry, Center of Dental Medicine, Faculty of Medicine, University of Zurich, Zurich, Switzerland.
authors.forename: Theodore
authors.initials: T
authors.lastname: Eliades
authors.affiliation: Department of Oral Technology, School of Dentistry, University of Bonn, Bonn, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Bourauel
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008963:Molar; D009967:Orthodontic Appliances / Q000009:adverse effects; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D014059:Tongue
keywords: fixed appliances; labial appliances; lingual appliances; orthodontics