Amaç: Bu çalışmanın amacı, deneysel olarak indüklenen osteoartrit (OA)

Objective: The aim of this study is to investigate the changes of temporomandibularjoint (TMJ) by experimentally induced osteoarthritis (OA) andthe effectiveness of botulinum toxin A (BTX-A) treatment via histopathologicaland biochemical methods.Methods: Sprague-Dawley rats, aged 8 to 10 weeks, were used in thisstudy. Intra-articular monosodium iodoacetate (MIA) solution was injectedbilaterally into two experimental groups to induce TMJ osteoarthritis.Sterile 0.9% NaCl solution was injected to TMJ of healthy control group bilaterallyto investigate the effect of trauma by intra-articular injection. Developmentof experimental osteoarthritis took 4 weeks, and blood sampleswere harvested from MIA group and examined to prove the presence ofinduced osteoarthritis. OA-induced eight rats with BTX-A. Another OA-inducedeight rats were classified as a control group and intra-articular 0.9%NaCl solution was injected bilaterally. All samples were sacrificed 6 weeksafter treatment. Blood samples and specimen of TMJ were harvested fromall rats and examined histopathologically and biochemically.Results: BTX-A and 0.9% NaCl solution groups showed some improvementcompared with untreated MIA group but it was not statistically significant.There was no sign of trauma in 0.9% NaCl solution-injected healthy group.Pathological findings were also consistent with the biochemical results.Conclusion: BTX-A was not successful at treatment of OA and is not a properselection especially when used intra-articularly.