Oral health-related quality of life, experience and satisfaction in adolescents treated for dental crowding with self-ligating or conventional fixed appliances: a multicentre randomized controlled trial.

Abstract

Background: Dental crowding affects nearly half of European adolescents and can negatively impact oral health-related quality of life (OHRQoL), particularly emotional and social well-being dimensions. Orthodontic treatment aims to improve function, aesthetics, and psychosocial well-being, yet active treatment may temporarily impair OHRQoL due to pain, dietary restrictions, and oral hygiene challenges. Understanding how conditions affect patients requires both objective and subjective assessments, yet patient reported outcomes remain underreported in orthodontic research, especially when comparing treatment techniques.

Objectives: To evaluate and compare OHRQoL, treatment motivation, expectations, quality of care and attention, and satisfaction in adolescents with dental crowding treated with two fixed appliance systems without extractions, and to explore factors associated with satisfaction with treatment outcomes.

Trial design: Multicentre, two-arm, parallel-group, superiority randomized controlled trial, with pooled analyses of both treatment groups, sex-stratified comparisons, and analyses exploring associations.

Methods: Adolescents (n = 132), 12-17 years, with dental crowding were randomized with 1:1 ratio using computer generated random permuted blocks, stratified by sex, to receive fixed appliance treatment without extractions with either a conventional bracket system (CB; Victory) or a passive self-ligating bracket system (PSLB; DamonQ) at four orthodontic clinics. Primary outcome was Child Perceptions Questionnaire 11-14 (CPQ) score change. Two items were omitted; sensitivity analysis confirmed minimal impact on results. Secondary outcomes were patient experience and satisfaction questionnaires (10-point scale) assessed before treatment (T0), post-alignment (T1), and post-treatment (T2). Because of the nature of the treatments, only assessors could be blinded.

Results: Both the CB (♀39, ♂31) and PSLB (♀34, ♂28) groups reported improved OHRQoL (median CPQ score change T0-T2 for total sample: 4.5; r = 0.37, P < .001) with minor intergroup differences. Oral symptoms and functional limitations worsened at T1 then improved by T2 (median change T0-T2 for each domain: 1, r = 0.23, 0.27, respectively, P < .001), whereas emotional and social well-being improved throughout treatment (median change T0-T2 for each domain: 1; r = 0.28, P < .001). Median scores were high for motivation (9) and overall satisfaction with treatment outcomes (≥9), and low for regretting having started treatment (1). Correlations between treatment expectations and satisfaction were observed (ρ = 0.330, P < .001). Minor harms expected during orthodontic treatment included plaque accumulation, chafing and gingivitis.

Conclusions: This study indicates that fixed appliance treatment for dental crowding leads to improvements in OHRQoL, with temporary declines during treatment, and high patient satisfaction in the studied sample. Patients reported satisfaction with the changes achieved, dental appearance, and did not regret having started treatment. The results demonstrate possible benefits of treatment, patient-centred care, and support the use of patient reported outcomes in orthodontic practice.

Trial registration: ClinicalTrials.gov (NCT05664282) 2022-11-24.