Figure 1.

(a) Normal rat temporomandibular joint (TMJ) tissue (×100) showing a thin synovial membrane (synovium) without any evidence of inflammation. (b-d) Adjuvant-induced arthritis in rat TMJ showing: (b) Hypertrophic and hyperplastic synovial membrane with cumulous infiltration of mononuclear inflammatory cells and pronounced dilated vessels (arrow) (×100); (c) redundant folds of hyperplastic synovial lining (asterisks) and infiltration with inflammatory cells (arrows) (×100); (d) increased density and adhesion of synovial resident cells (arrow) (×400). SM: synovial memberane.