Asymmetric Rapid Maxillary Expansion in Mixed Dentition: A Cephalometric Evaluation

Methods: The study was consisted of 14 girls and 16 boys in mixed dentition (mean age 8,74 ± 0,56 years) needing asymmetric maxillary expansion due to unilateral posterior crossbite when the jaws in centric relationship. Lateral cephalograms collected before and after treatment; after retention period. Twelve skeletal, 4 dental and 2 soft tissue measurements were used to investigate on the dentofacial changes. The changes were evaluated by repeated measurements analysis of variance and paired sample t test.

Results: After active treatment and after the retention period, fourteen and six measurements showed statistically significant differences (p<0.05), respectively. The most significant changes which found about mandibla and upper, lower central incisors measurements at end of the active treatment period were not stable at retention period, except maxillary skeletal changes. When overall differences considered, SNA angle, ANB angle, N-ANS, SN perpendicular to ANS, SN perpendicular to PNS and SV perpendicular to A point measurements increased (p<0,05). As a result, maxilla moved forward, downward and middle face height increased.

Conclusions: The results suggest that this treatment approach significantly affects the vertical and sagittal position of maxilla. This situation resulted from orthopedic effective of appliance.