Comparison of adverse effects between lingual and labial orthodontic treatment.

OBJECTIVE:To compare adverse effects between labial and lingual orthodontic treatments through a systematic review of the literature. MATERIALS AND METHODS:The protocol of this systematic review (CRD42012002455) was registered in the International Prospective Register of Systematic Reviews (PROSPERO). An electronic search was conducted in PubMed, Embase, Web of Science, CENTRAL, SIGLE, ProQuest Dissertations & Theses, and ClinicalTrial.gov for articles published between January 1980 and December 2012. Primary outcomes included pain and caries; secondary outcomes were eating difficulty, speech difficulty, oral hygiene, and treatment duration. Meta-analyses were conducted in Comprehensive Meta-Analysis version 2.2.064. RESULTS:Six studies were included, two randomized controlled trials and four clinical controlled trials; of these, four were medium quality and two were low quality in terms of the risk of bias. Five of the six outcomes were evaluated in the included studies, and treatment duration was not; pain, eating difficulty, speech difficulty were statistically pooled. Meta-analysis revealed that the pooled odds ratios were 1.20 (95% confidence interval [CI]  =  0.30-4.87) for overall pain, 32.24 (95% CI  =  14.13-73.55) for pain in tongue, 0.08 (95% CI  =  0.04-0.18) for pain in cheek, 0.11 (95% CI  =  0.03-0.42) for pain in lip, 3.59 (95% CI  =  1.85-6.99) for eating difficulty, and 8.61 (95% CI  =  3.55-20.89) for speech difficulty. Sensitivity analysis showed consistent results except for eating difficulty. No publication bias was detected. CONCLUSIONS:The likelihood of overall pain was similar between the two modalities. Patients who underwent lingual orthodontic treatment were more likely to suffer from pain in the tongue and less likely to suffer from pain in the cheek and lip. Lingual orthodontic treatment increased the likelihood of speech difficulty. Eating difficulty, oral hygiene, caries, and treatment duration could not be compared in this systematic review.