The impact of orthodontic treatment on the dental occlusion and oral health-related quality of life of individuals with cleft lip and/or palate

Background: Children with cleft lip and/or palate (CL/P) are a special group of orthodontic patients. Oral health-related quality of life (OHRQoL) is an important aspect of treatment outcome that is becoming popular in its application in orthodontics, but its relationship with clinical treatment outcomes remains unclear. Objectives: To compare OHRQoL and clinical treatment outcomes of a sample of children with cleft lip and/or palate and non-cleft children before and after orthodontic treatment in order to determine whether there is an association between the two outcome measures. Methods: A prospective observational longitudinal study was conducted of 60 consecutive adolescent patients (33 CL/P and 27 non-cleft) who received orthodontic treatment at Christchurch Hospital, New Zealand. The two outcome measures were a self-reported OHRQoL outcome assessed by the short form 8 item Child Perception Questionnaire (CPQ-ISF 8) and an orthodontic treatment outcome assessed by the Peer Assessment Rating (PAR) index. Results: Both CL/P and non-cleft groups had comparable pretreatment malocclusion severity with similar baseline and end of treatment OHRQoL. Although both groups showed similar improvements in OHRQoL following orthodontic treatment, the non-cleft group had significantly greater improvement in their PAR outcome. There was no association detected between OHRQoL and the PAR improvement. Conclusion: Both study groups had similar OHRQoL changes following orthodontic treatment despite the non-cleft group having better orthodontic treatment outcomes. There is a lack of correlation between the patient's self-assessment OHRQoL and clinically based orthodontic treatment outcomes.