Anteroposterior Orthopedic Changes using a Bonded Maxillary Expander

Cristiane Aparecida de Assis CLARO, Weber URSI, Rosana Villela CHAGAS, Gerval de ALMEIDA

The objective of this research was to evaluate prospectively the sagital position of the maxilla and the mandible after rapid maxillary expansion (RME) using a bonded expander. The sample comprised 22 children, 6 males and 16 females, between the ages of seven and eleven. All patients presented clinical signs of maxillary constriction and were subjected to the expansion procedure, using two expansion rates, eleven with 1/4 turn per day and the remainder with 4/4 turns per day, until 32 quarter turns were obtained, which was sufficient to normalize maxillary dimensions in all cases. After the expansion was completed, the appliance was left in place for 5 months, removed and a palatal plate inserted for a retention period of 7 months. Lateral cephalograms were obtained before the appliance was cemented, after it was removed, and after 7 months of retention. To determine possible sagital changes of maxillary and mandibular relationship and position, linear and angular variables were utilized. Results made it evident that there were no significant changes between the two expansion rates. It was then possible to analyse all patients together, which showed that RME using a bonded occlusally covered appliance did not permanently alter either maxillary or mandibular sagital positions. The maxillo-mandibular relationship improved at the end of the experiment compared to the 5 months. Therefore, no deleterious permanent sagital skeletal effects were observed.

Keywords: Rapid maxillary expansion. Bonded expander.

Saturday, December 28, 2024 23:56