Osteoarthrosis (OA) is a degenerative disease characterized by loss of joint cartilage, remodelling of the subchondral bone, narrowing of joint spaces and the formation of osteophytes. Animal models are used to study the mechanisms of OA, as well as to test the effects of anti-osteoarthrosis drugs. The objective of the present study was to determine the changes identifiable by imaging techniques occurring in rabbit temporomandibular joints (TMJ) at 15, 25 and 45 days after OA inducement by monoiodoacetate (MIA) and papain. The imaging technology used was cone-beam computerised tomography (CBCT). The model animals were 22 young adult male New Zealand rabbits, divided randomly into three study groups: Four rabbits in the control group, nine in the papain experimental group and nine in the monoiodoacetate (MIA) experimental group. OA was induced by arthrocentesis in the lower compartment of both TMJs. The rabbits were examined by CBCT at 15, 25 and 45 days after the injection of MIA and papain. The mandibular condyles presented loss of their rounded shape, deformation of the condyle or mandibular fossa, cortical irregularity, cortical wear and changes in the dimensions of the condyle. OA induction by MIA and papain generates changes observable by CBCT in the dimensions of the mandibular condyle in rabbits. Both inducers promote signs compatible with OA on the joint surfaces of the TMJ; MIA promotes more expressive changes.
KEY WORDS: Induced osteoarthrosis; Cone-beam computerized tomography; Monoiodoacetate; Papain; Temporomandibular joint.