M-CSF accelerates orthodontic tooth movement by targeting preosteoclasts in mice

Area of Science:

• Biomedical research
• Orthodontics
• Cell biology

Background:

• Osteoclast recruitment and differentiation are crucial for tooth movement during orthodontics.
• Macrophage colony-stimulating factor (M-CSF) is an early factor involved in osteoclastogenesis.

Purpose of the Study:

• To evaluate the efficacy of M-CSF in accelerating osteoclast recruitment and differentiation for faster tooth movement.
• To investigate the effect of different M-CSF dosages on tooth movement and osteoclast activity.

Main Methods:

• Characterized osteoclast precursors in the periodontal ligament (PDL) using immunohistochemistry in a mouse model.
• Administered two dosages of M-CSF to molars under orthodontic force.
• Measured tooth movement and analyzed M-CSF downstream gene expression in the PDL.

Main Results:

• Monocytes differentiated into preosteoclasts and were recruited to the PDL, with multinucleated osteoclasts appearing after 6 days.
• A lower M-CSF dose significantly increased tooth movement and expression of M-CSF downstream genes and TRAP.
• A higher M-CSF dose reduced the expression of one M-CSF downstream gene and potentially inhibited osteoclast formation.

Conclusions:

• Optimal exogenous M-CSF administration can accelerate tooth movement.
• This finding suggests potential for M-CSF in clinical orthodontic applications to expedite treatment.
• Further clinical studies are warranted to validate these findings.