Eligible studies were randomised controlled trials (RCTs), controlled clinical trials (CCTs) and case series with a sample size of at least five. Eligible participants were adolescents or adults who had undergone a SARME with a bone-borne palatal distractor. Inclusion criteria for outcomes were not specified.
Median age of participants ranged from 13.9 to 26.4 years (the youngest was 11 and the oldest 43 years). Most studies had participants with developmental deformity; a few participants had cleft lip palate, other congenital deformity or unknown diagnosis. Five different distractors were used: Trans Palatal Distractor (TPD); Rotterdam Palatal Distractor (RPD); Madeburg Distractor (MD); Dresden Distractor (DD); and Maxillary Widening Device (MWD). An average latency period of 5.6 days (range one to seven) before the start of activation was reported. The average rate of distraction was 0.66mm/day (range 0.33 to 1mm/day). Outcomes measured included assessment of expansion in terms of changes in dental and skeletal structures, assessment of orthodontic side effects in terms of tipping of teeth, treatment related difficulties, dental and periodontic side effects and assessment of pain.
Two reviewers independently undertook selection of studies. Differences were resolved by consensus.