Background: Osseointegrated implants are considered as clinically non-movable. Parathyroid hormone (PTH) is known to play a significant role in the regulation of bone remodeling and in intermittent, low doses, result in osteoanabolic effects. This study aimed to investigate the effects of PTH and corticotomy, both under traction force, on osseointegrated implants. Methods: Four implants—two in each hemimandible—were placed in each of the three study mongrels. Each mongrels were designated as control, normal dose PTH (PTH-1), and high dose PTH (PTH-2) groups, with each groups further subdivided into non-surgery implant and surgery implant. After osseointegration, mechanical force with NiTi closed coil springs (500 g) was applied around each implants. Corticotomy was performed around one of four implants in each mongrels. Parathyroid hormone was administered locally on a weekly basis for 20 weeks. Clinical movement of the implants were evaluated with the superimposed 3D- scanned data, bone- microarchitectural and histologic examinations. Results: Superimposition analysis showed continuous movement of the non-surgery implant of PTH-1 group. Movement was further justified with lowest bone implant contact (adjusted BIC; 44.77%) in histomorphometric analysis. Upregulation of bone remodeling around the implant was observed in the normal dose PTH group. In the surgery implants, the remarkably higher adjusted BIC compared to the non-surgery implants indicated increased bone formation around the implant surface. Conclusion: The results indicate that the catabolic and anabolic balance of osseointegrated implants in terms of bone remodeling can be shifted via various interventions including pharmacological, surgical and mechanical force. Clinical relevance: Upregulated bone remodeling by PTH and corticotomy under continuous mechanical force showed the possible implications for the movement of osseointegrated dental implant.
Bibliographical noteFunding Information:
The work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2020R1A2C4001842 and 2017R1C1B5018349).
The work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2020R1A2C4001842 and 2017R1C1B5018349). The funding bodies played no role in the design of the study and collection, analysis, and interpretation of data. Acknowledgments
© 2020, The Author(s).
- Bone remodeling
- Orthodontic force
- Parathyroid hormone