The Histological Effects of Gold Nanoparticles on the Condyle of Temporomandibular joint of Adult Male Albino Rats

Aim: To identify the histological effects of AuNPs on the condyle of temporomandibular joint of adult male Albino rats histologically and immunohistochemicaly. Materials and methods: Sixteen male Albino rats were allocated to; Control group (Gp I): rats received distilled water daily for 14 days. AuNPs‑treated group (Gp II): rats received 40μg AuNPs /kg daily for 14 days. Serum level of reduced glutathione (GSH) was measured and statistically analysed. Condyles were stained by hematoxylin and eosin (H & E) and anti-caspase-3. Caspase-3 area percentage was measured and statistically analysed. Results: Statistical analysis of GSH serum level showed a high significant decrease in Gp II when compared to Gp I. Examination of H&E stained sagittal sections of GpII showed pannus formation with inflamed synovium invading the condylar bone destructing its normal architecture. Condylar cartilage showed apparent decreased thickness and the bone revealed widened marrow cavities, inflammatory cell infiltration with osteoclasts in Howship’s lacunae. Immunohistochemicaly, GpII showed too many areas positive to anti-caspase 3 that was statistically significant when compared to GpI. Conclusion: Oral administration of AuNPs induced destructive histological changes and apoptosis in both cartilage and bone of mandibular condyle.