Parathyroid hormone intermittent administration promotes delay on rat incisor eruption

Area of Science:

• Dental research
• Bone biology
• Endocrinology

Background:

• Tooth eruption is a complex biological process influenced by various factors.
• Parathyroid hormone (PTH) plays a crucial role in bone metabolism.
• Understanding PTH's effect on tooth eruption is vital for orthodontic and regenerative therapies.

Purpose of the Study:

• To investigate the impact of intermittent parathyroid hormone (PTH) (1-34) administration on rat lower incisor eruption rates.
• To assess the effects of PTH (1-34) on Sharpey fibers and alveolar bone formation under different functional conditions.

Main Methods:

• Wistar male rats were administered PTH (1-34) or vehicle three times weekly for 31 days.
• Alizarin injections were used to track mineralization and eruption.
• Mandibular samples were analyzed using fluorescence and scanning electron microscopy for eruption rate, bone formation, and Sharpey fiber characteristics.

Main Results:

• PTH (1-34) treatment significantly decreased lower incisor eruption rates across normo-, hyper-, and hypofunctional conditions.
• PTH (1-34) administration led to increased alveolar bone formation.
• An enhanced area density of Sharpey fibers was observed in PTH-treated rats.

Conclusions:

• Intermittent PTH (1-34) administration effectively reduces the rate of tooth eruption.
• The observed reduction in eruption is attributed to enhanced bone formation and increased Sharpey fiber density.
• PTH (1-34) shows potential as a therapeutic agent in modulating tooth movement and bone regeneration.