Immediate loading of orthodontic palatal implants with masticatory forces

Objective: To clinically evaluate the immediate loading of palatal implant (PI) for maximal orthodontic anchorage. Contrary to the standard-protocol with the suggested healing time of 12 weeks, the PIs in this study were subjected to immediate loading using a welted Transpalatal Arch (TPA).

Methods: 16 Patients (mean age 14.22 ± 1.37 years) with orthodontic indications for maximal anchorage were selected randomly into two groups. In the immediate loading (IL) Group (n = 8, mean age 14.15 ± 1.2 years) Orthosystem® Palatal Implants (PI) were insert and functionally loaded after 72 hours with a 1.2 x 1.2 mm thick rigid TPA connected to the upper first molar bands and to the PI. In the conventional loading (CL) Group (n = 8, mean age 14.3 ± 1.57 years) the same loading was provided following an unloaded 12 week healing period. Following orthodontic treatment the PIs were explanted and bone samples were histomorphometrically analyzed using light microscopy. The data was fed into an imaging PC (QICAM FAST 1394, Qimaging). The Bioquant Osteo software V7.10.10 (BIOQUANT Image Analysis Corporation, Nashville, Tennessee) was used for data analysis.

Results: No PIs were lost prior to surgical explantation. The orthodontic treatment was successful in both groups. In the IL group a mean bone-to-implant contact (BIC) of 55.0% +/- 21.6 was observed. In the CL group, the BIC was 73.1% +/- 19.8. The difference between the two groups was not significant (p=0.1661). Neither age nor gender differences were demonstrated between the groups.

Conclusion: There is no significant difference in osseointegration between the unloaded healed and the immediately loaded PIs. Both protocols are found to be clinically effective, provided good primary stability is achieved. It is concluded that orthodontic treatment time can be reduced by the 12 week healing period, as loading can occur almost immediately following PI placement.