Structure of peripheral cementum of normal equine cheek teeth.

This research article investigates the structure of peripheral cementum in healthy equine cheek teeth, noting significant variations in thickness in different parts of the tooth and the presence of a complex, intricate structure of living cells.

Research Methodology

• The study used a diverse set of observation and analysis techniques including gross observation, light microscopy, and both scanning and transmission electron microscopy to map out the intricacies of equine cheek teeth.
• The research included a sample set of four horses of varying ages (4, 8, 17, and 30 years) to encompass a wide cross-section of time and offer some insight into potential age-related changes in equine dental structure.

Findings: Thickness Variations

• The research found noticeable differences in the thickness of cementum (the calcified substance covering the root of the tooth) on the occlusal (biting) surface of the teeth depending on the location. Specifically, the buccal (cheek-facing) aspect had thicker cementum than the lingual (tongue-facing) aspect of mandibular (lower jaw) teeth.
• Conversely, in maxillary (upper jaw) teeth, the palatal (roof of mouth-facing) aspect exhibited greater cementum thickness than the buccal aspect.
• There was an absence of peripheral cementum on the interdental aspects (spaces between teeth) for both mandibular and maxillary cheek teeth.

Findings: Microscopic Observations

• The study demonstrated that the peripheral cementum covering the gingival (gum) region was notably thicker than the cementum layering the alveolar (bone-containing tooth sockets) part of the embedded tooth.
• Under microscopic analysis, the cementum was found to exhibit a triple-layer composition of primary, secondary, and tertiary cementum. The increased cementum thickness in the gingival region was specifically attributed to tertiary cementum.
• All three layers possessed live cementocytes (cells responsible for depositing cementum).
• The cementum was revealed to contain a well-organized vascular system and nerve bundles, marking it as a vital, dynamic tissue.

Implications

• The findings reported in the research shine light on the complexities of cementum, transforming it from a passive entity to an active, living tissue capable of adjusting and responding to the horse’s needs.
• This knowledge can enhance understanding of the etiology (cause) and pathogenesis (how disease develops) of dental caries (cavities) and periodontal disease (gum disease) in horses, which may ultimately assist in disease prevention and treatment.