IADR Abstract Archives
Low-intensity Pulsed Ultrasound Enhances Osseointegration via Elevated αCGRP
Objectives: This study was aimed to investigate whether low-intensity pulsed ultrasound (LIPUS) could improve osseointegration of dental implant and if so whether elevated expression of calcitonin gene-related peptide-alpha (αCGRP) by LIPUS is part of the mechanism.
Methods: Dorsal root ganglion (DRG) neurons from C57BL/6(αCGRP+/+) or αCGRP-/- mice were treated with LIPUS and the change in αCGRP secretion was analyzed. Osteoblasts(OBs) from αCGRP+/+ mice were subsequently cultured in conditioned medium from LIPUS-treated DRG neuron cultures, and their proliferative rates as well as expression of osteoblastic activity markers such as alkaline phosphatase (ALP), collagen-1 (COL-1), osteocalcin (OCN), osteopontin (OPN) and Runx2 were examined. In vivo tests included wild-type group (n=12) and αCGRP-/- group (n=12) of mice. All animals had their maxillary first molar extracted and a titanium implant was immediately placed in each socket. Half of the animals (n=6) in each group were treated with LIPUS while others were control sub-group. The bone formation around implants and the expression of αCGRP were analyzed.
Results: Secretion of αCGRP by DRG neurons (αCGRP+/+) was promoted after LIPUS exposure, and the conditioned medium from them enhanced expression levels of ALP, COL-1, OCN, OPN and RUNX2 of OBs (p<0.05), while OBs cultured in conditioned medium from LIPUS-treated αCGRP-/- neurons were not affected. Proliferative rates of OBs cultured in conditioned medium were unaffected by the DRG neurons no matter whether they were pretreated by LIPUS. In vivo, wild-type group displayed elevated αCGRP expression and better osseointegration after LIPUS treatment, while αCGRP-/- group showed no such effect.
Conclusions: Our results demonstrate that LIPUS can promote osseointegration and αCGRP might be one of the mechanisms involved.
Methods: Dorsal root ganglion (DRG) neurons from C57BL/6(αCGRP+/+) or αCGRP-/- mice were treated with LIPUS and the change in αCGRP secretion was analyzed. Osteoblasts(OBs) from αCGRP+/+ mice were subsequently cultured in conditioned medium from LIPUS-treated DRG neuron cultures, and their proliferative rates as well as expression of osteoblastic activity markers such as alkaline phosphatase (ALP), collagen-1 (COL-1), osteocalcin (OCN), osteopontin (OPN) and Runx2 were examined. In vivo tests included wild-type group (n=12) and αCGRP-/- group (n=12) of mice. All animals had their maxillary first molar extracted and a titanium implant was immediately placed in each socket. Half of the animals (n=6) in each group were treated with LIPUS while others were control sub-group. The bone formation around implants and the expression of αCGRP were analyzed.
Results: Secretion of αCGRP by DRG neurons (αCGRP+/+) was promoted after LIPUS exposure, and the conditioned medium from them enhanced expression levels of ALP, COL-1, OCN, OPN and RUNX2 of OBs (p<0.05), while OBs cultured in conditioned medium from LIPUS-treated αCGRP-/- neurons were not affected. Proliferative rates of OBs cultured in conditioned medium were unaffected by the DRG neurons no matter whether they were pretreated by LIPUS. In vivo, wild-type group displayed elevated αCGRP expression and better osseointegration after LIPUS treatment, while αCGRP-/- group showed no such effect.
Conclusions: Our results demonstrate that LIPUS can promote osseointegration and αCGRP might be one of the mechanisms involved.