Elastic Chain Premaxillary Retraction Appliance Does Not Increase Inter-Canthal Dimension in Patients with Bilateral Cleft Lip and Palate

Abstract

Objective To determine if the elastic chain premaxillary retraction (ECPR) appliance increases inter-medial and inter-lateral canthal dimension in patients with bilateral complete cleft lip and palate (BCLP). Design Retrospective cohort study. Setting Specialized tertiary care facility. Patients, Participants 126 patients with BCLP; 75 had ECPR, 51 had no pre-surgical manipulation. Interventions Three-dimensional facial photographs were obtained prior to insertion of appliance (T0), post-appliance therapy prior to appliance removal/labial repair (T1), and several months after labial repair (T2) for a longitudinal ECPR group, and were obtained after age 4 years (T3) for a non-longitudinal ECPR group and for the non-ECPR group. Main Outcome Measures Inter-medial and inter-lateral canthal dimension (en-en, ex-ex) was determined for all groups/time-points. Measurements were compared between groups and to norms. Results The mean en-en and ex-ex was 32.6 ± 3.2 mm and 84.4 ± 6.3 mm for the ECPR group and 33.5 ± 3.1 mm and 86.7 ± 7.2 mm for the non-ECPR group at T3. Inter-medial and inter-lateral canthal dimensions were significantly greater than normal ( P < .05) in both groups; there was no significant difference between groups ( P > .05). The mean en-en and ex-ex for the Longitudinal ECPR group was 27.5 ± 2.4 mm and 66.7 ± 3.7 mm at T0, 29.6 ± 2.4 mm and 70.4 ± 2.9 mm at T1, and 29.2 ± 2.3 mm and 72.3 ± 3.8 mm at T2. en-en and ex-ex increased significantly from T0-T1 ( P < .05), decreased at T2 ( P > .05) and was significantly larger than normal at all time-points ( P < .05). Conclusions Inter-medial and inter-lateral canthal dimension increased after ECPR but returned to baseline growth trajectory. These dimensions were above normal at all time-points. There was no difference between those that did and did not have dentofacial orthopedic manipulation.