Effects of Age on Bonded Rapid Palatal Expansion in Children

Objectives: The purpose of this study was to examine the transverse effects of rapid palatal expansion (RPE) on the maxilla of children and the relationship between the effects and age. Methods: Thirty five children, who required RPE with a mean age of 10.1 (range: 8.1-13.1) were included. Their skeletal ages were determined to be a mean of 10.2 (range 7.3-13.5) by hand-wrist films. Each patient had a cone beam CT (CBCT) image taken at the pretreatment appointment (T1) and at the completion of RPE (T2). The measurements taken for each patient included the basal bone width and sutural opening at the level of the first molar, second premolar, first premolar, and canine. The dental tipping and nasal width changes were determined at the level for the first molar. Regression analysis and Student t tests were conducted to measure the significance. Results: There was a significant increase in basal bone width, sutural opening, intermolar angulation, and nasal width in response to RPE. The skeletal age within the range of 7.3 – 13.5 had no significant effect on the amount of changes measured. When dividing the sample into two groups based on their skeletal ages, there was no significant difference in the amount of changes measured between the younger group (7.3-10) and older group (10-13.5). In addition, we found that as the amount of sutural opening increased, the amount of nasal width increased at the level of the first molar as well (P=0.001). Conclusions: There was an increase in the basal bone width, sutural opening, molar tipping, and nasal width dimension as a result of RPE. Skeletal age within the range of 7.25-13.5 might not be correlated with the transverse maxillary effects in basal bone width, sutural opening, and dental tipping and nasal width. Also, a positive relationship was found between sutural opening and nasal width increase.