title: Sufficient retention.
authors.forename: K D
authors.initials: KD
authors.lastname: Johnston
authors.forename: J D
authors.initials: JD
authors.lastname: Snelling
mesh_terms: D002648:Child; D005547:Foreign Bodies / Q000601:surgery; D006801:Humans; D008297:Male; D009960:Oropharynx / Q000601:surgery; D009967:Orthodontic Appliances / Q000009:adverse effects*; D010155:Palatal Expansion Technique / Q000295:instrumentation