Pain and discomfort during the first week of maxillary expansion using two different expanders: patient-reported outcomes in a randomized controlled trial

BACKGROUND: Quad Helix (QH) is the appliance most preferred by orthodontists to correct unilateral posterior crossbite in the early mixed dentition while other orthodontists suggest rapid maxillary expansion (RME) on deciduous teeth in these patients. OBJECTIVES: To evaluate and compare perceived pain intensity, discomfort, functional jaw impairment, and analgesic consumption during the first week of treatment with either RME or QH appliances. TRIAL DESIGN: Two-arm parallel group, two-centre, randomized controlled trial. MATERIAL AND METHODS: Seventy-two patients, mean age 9.5 (SD ±0.8) years, with unilateral posterior crossbite requiring maxillary expansion were randomly allocated to either the RME (22 boys, 14 girls) or QH (22 boys, 14 girls) group. Validated questionnaires were used to assess pain intensity, discomfort, jaw function impairment, and analgesic consumption, on the first, fourth, and seventh days after appliance insertion and activation. BLINDING: Due to clinical limitations, only the outcome assessors were blinded to the groups to which the patients were allocated. RESULTS: Seventy patients completed the questionnaires. Pain from the tongue and chafe from the appliance were significantly higher in the QH group on the first day of treatment (P = 0.003 and P = 0.000, respectively). On the fourth day, the chafe from the appliance was still significantly higher in the QH group (P = 0.007). Speech was affected in both groups on day 1; this impairment continued and was significantly higher in the RME group days 4 and 7. No significant difference in analgesic consumption was found between the groups at any time. The analgesic consumption was highest at day 1 of treatment. HARMS: No harm was observed in any patient. LIMITATIONS: Double blinding was not possible due to the clinical limitations. CONCLUSION: During the initial 4 days of treatment, pain from the tongue and chafe from the appliance caused the most reported inconvenience in the patients in the QH group. A majority of reported visual analogue scale values were in the lower mid-range, suggesting low to moderate pain and discomfort in both groups. CLINICAL TRIAL REGISTRATION: NCT04458506