Equine Odontoclastic Tooth Resorption and Hypercementosis: Histopathologic Features.

Area of Science:

• Veterinary Pathology
• Equine Dentistry
• Oral Surgery

Background:

• Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a painful, progressive dental condition affecting older horses.
• It is often underdiagnosed and can be mistaken for other conditions like cementoblastoma.
• The etiology of EOTRH remains unknown.

Purpose of the Study:

• To describe the histopathologic features of EOTRH in a cohort of horses.
• To enhance veterinary pathologists' recognition of EOTRH.
• To differentiate EOTRH from other dental pathologies.

Main Methods:

• Histopathologic examination of dental samples from 17 affected horses.
• Analysis of affected teeth, including cemental and dentinal lysis.
• Evaluation of associated endodontic and periodontal disease.

Main Results:

• Affected teeth showed cemental hyperplasia and lysis, with severe cases exhibiting bulbous enlargement.
• Necrotic debris, bacteria, and plant material were found in areas of lysis.
• Dentinal lysis, endodontic disease, and lymphoplasmacytic inflammation associated with periodontal disease were common findings.

Conclusions:

• EOTRH involves both cemental and dentinal lysis, with resorption potentially initiating externally.
• Accurate diagnosis requires a comprehensive approach including clinical history, gross findings, and radiography.
• Increased awareness and understanding of EOTRH histopathology are crucial for improved veterinary care.