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Frontiers in veterinary science2026; 13; 1810777; doi: 10.3389/fvets.2026.1810777

Dental disorders are associated with minimal synovial changes in the temporomandibular joint in horses.

Abstract: Dental disorders have been proposed as factors contributing to temporomandibular joint (TMJ) discomfort in horses, but objective evidence linking these conditions to synovial fluid alterations remains limited. This study evaluated whether the severity of dental abnormalities influences the physicochemical and cytological characteristics of TMJ synovial fluid and whether occlusal adjustment induces measurable synovial changes over time. Unassigned: Thirty-three horses were assigned to mild, moderate, or severe dental abnormality groups. Synovial fluid was collected bilaterally from the discotemporal joint compartment before and 30, 60, and 90 days after dental treatment. Physicochemical and cytological variables were compared among severity groups and sampling times. Unassigned: Synovial fluid characteristics remained stable across most variables, groups, and time points. A clearer synovial fluid appearance was observed in the contralateral TMJ of horses with severe dental abnormalities at 60 and 90 days, whereas an increased synovial fluid volume was detected in the ipsilateral joint of horses with moderate dental abnormalities at 90 days. No other variables differed significantly ( > 0.05). Unassigned: Dental disorders and their correction produced limited measurable effects on synovial fluid composition in the equine TMJ, indicating substantial biochemical stability. These findings suggest that, despite the proposed association between dental abnormalities and TMJ dysfunction, synovial fluid physicochemical and cytological characteristics remain largely unaffected by dental abnormality severity and occlusal adjustment.
Copyright © 2026 Kunz, Mendes, Granella, Costa, Corrêa, Souza, Fonteque and Kau-Strebinger.
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Publication Date: 2026-06-30 PubMed ID: 42453973PubMed Central: PMC13364583DOI: 10.3389/fvets.2026.1810777Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study investigated whether dental disorders in horses affect the synovial fluid of the temporomandibular joint (TMJ) and whether dental treatments lead to changes in this fluid over time.
  • The research found that dental abnormalities and their correction caused minimal changes in the TMJ synovial fluid, suggesting stable joint biochemistry despite dental issues.

Background and Purpose

  • Temporomandibular joint (TMJ) discomfort in horses has been linked to dental problems, but there is limited objective evidence directly connecting dental disorders with changes in the joint’s synovial fluid.
  • Synovial fluid provides lubrication and nutrition in joints, and alterations in its composition can indicate joint disease or dysfunction.
  • The research aimed to:
    • Determine if the severity of dental abnormalities correlates with changes in the physicochemical (e.g., clarity, volume) and cytological (cell-related) properties of TMJ synovial fluid.
    • Assess whether occlusal adjustments (dental treatments to correct bite) induce changes in synovial fluid composition over a 90-day period.

Study Design and Methods

  • Participants: 33 horses categorized into three groups based on dental abnormality severity:
    • Mild dental abnormalities
    • Moderate dental abnormalities
    • Severe dental abnormalities
  • Sample Collection:
    • Synovial fluid was obtained from both the left and right discotemporal compartments of the TMJ.
    • Samples were taken at four time points:
      • Before dental treatment (baseline)
      • 30 days post-treatment
      • 60 days post-treatment
      • 90 days post-treatment
  • Variables Measured: Physicochemical characteristics (e.g., fluid clarity, volume) and cytological parameters (cell type and count).
  • Comparisons were made among dental severity groups and across the different sampling times to detect any changes or patterns.

Key Findings

  • Overall Stability:
    • Most synovial fluid characteristics remained stable regardless of dental abnormality severity or sampling time.
    • No major changes in cytological parameters were observed.
  • Notable Observations:
    • A clearer appearance of synovial fluid was noted in the TMJ contralateral (opposite side) to severe dental abnormalities at 60 and 90 days post-treatment.
    • An increased volume of synovial fluid was detected in the TMJ ipsilateral (same side) to moderate dental abnormalities at 90 days post-treatment.
    • These were isolated findings and other physicochemical variables did not differ significantly.
  • No significant inflammatory or cytological changes were found that would suggest joint pathology linked to dental disorder severity or its treatment.

Conclusions and Implications

  • The study suggests that dental disorders in horses do not cause significant alterations in the TMJ synovial fluid’s biochemical and cytological profile.
  • Occlusal adjustments (dental treatments) produce minimal measurable effects on synovial fluid composition over a 90-day period.
  • These findings indicate substantial biochemical stability of the equine TMJ synovial environment despite dental abnormalities.
  • The results challenge the assumption that dental problems directly contribute to synovial inflammation or TMJ joint pathology measurable through synovial fluid analysis.
  • This information is important for veterinarians considering the relationship between dental health and TMJ disorders in horses, pointing toward the complexity of TMJ discomfort beyond detectable synovial changes.

Cite This Article

APA
Kunz JR, Mendes RP, Granella MCS, Costa A, Corrêa RR, de Souza AF, Fonteque JH, Kau-Strebinger S. (2026). Dental disorders are associated with minimal synovial changes in the temporomandibular joint in horses. Front Vet Sci, 13, 1810777. https://doi.org/10.3389/fvets.2026.1810777

Publication

Frontiers in veterinary science
ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 13
Pages: 1810777
PII: 1810777

Researcher Affiliations

Kunz, Joao Ricardo
  • Departamento de Medicina Veterinária, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina (Udesc), Lages, Brazil.
Mendes, Rubens Peres
  • Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
Granella, Milena Carol Sbrussi
  • Departamento de Medicina Veterinária, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina (Udesc), Lages, Brazil.
Costa, Adson
  • Departamento de Medicina Veterinária, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina (Udesc), Lages, Brazil.
Corrêa, Rodrigo Romero
  • Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
de Souza, Anderson Fernando
  • Departamento de Medicina Veterinária, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina (Udesc), Lages, Brazil.
Fonteque, Joandes Henrique
  • Departamento de Medicina Veterinária, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina (Udesc), Lages, Brazil.
Kau-Strebinger, Silvio
  • Unit of Morphology, Department of Biomedical Sciences and Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria.

Conflict of Interest Statement

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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