Development of coronal cementum in hypsodont horse cheek teeth.

This research examines how cementum, a hard substance covering the teeth, develops in the cheek teeth of horses. This study uses various scientific methods and technology, focusing on the horse’s lower 3rd permanent premolar teeth during different ages.

Methodology

• The researchers conducted the study by comparing lower 3rd permanent premolar teeth taken from horses of different ages (3.5, 4, and 5 years old).
• Various techniques and technologies were used to carry out the comparison, including radiography, microcomputed tomography (Miro-CT), light microscopy (LM), and scanning electron microscopy (SEM).

Findings and Observations

• The study found that before the cementum is formed on the crown of the tooth, specific cells that are resistant to tartrate acid (TRAP), known as odontoclasts, start resorbing the enamel surface of the reserve crown in the cheek tooth.
• The areas where the enamel was resorbed were relatively narrow, starting from the cuspal tips and moving in the apical direction during tooth development.
• Primary cementum was first deposited on the junction between enamel and cementum (ECJ) where the enamel was irregularly pitted, both at the infolding and peripheral enamel.
• By the time of tooth eruption, the infolding cementum filled the grooves completely.
• On the other hand, in the peripheral cementum, the secondary and tertiary cementum layers were sequentially deposited on the primary cementum. Here, these layers were continually laid down on the primary cementum coronally rather than apically throughout the horse’s life and served as the site where the periodontal ligaments were inserted.

Implications of the Study

• The resulting data suggests that the cementum covering horse cheek teeth is a complex and multifunctional tissue, adapting to serve its various necessary roles.
• This study adds valuable knowledge to the understanding of dental anatomy in horses which can potentially impact veterinary dental care for these animals.