| Material and methods. Stress-strain gauges (Intertechnology, Don Mills, Ontario) were attached to human adult cadavers and bonded to the bone adjacent to the mid-palatal and intermaxillary sutures using the MBond 200, cyanoacrylate adhesive (Intertechnology, Don Mills, Ontario). The gauges were attached to a P3 machine and forces exerted on the craniofacial complex using a modified RME. Values generated were converted to force in gram units.;Conclusions. Forces generated by RME devices are dissipated through the bone at levels that exceed orthopaedic force range. The further away from the site of force delivery, the lower the recorded values, suggesting dissipation involves many factors such as amounts of hard and soft tissue.;Results and discussion. After complete activation of the modified RPE appliance, maximum values were compiled and compared. The mean maximum force values for the mid-palatal suture was 986.58 grams (1203.72), while the intennaxillary suture site was 759.99 grams (1143.77). These forces are all at the level of orthopaedic in nature. Using a paired student t-test, it was found that there was a statistically significant difference in force values between the mid-palatal and intermaxillary sensor sites (p<0.05). No specimens were found to have either the mid-palatal or intermaxillary suture become patent following complete activation. The difference in values could indicate that the force generated by the modified RME becomes dissipated by the hard and soft tissues in the craniofacial complex and that the further away from the RME, the lower the recorded value. This may further support the theory that piezoelectricity mediates orthodontically induced alveolar remodelling by orthopaedic orthodontic appliances in the craniofacial complex. |
