Aim: To assess hyaluronic acid hydrogel /bone marrow stem cell-conditioned 
medium (MSC-CM with HA hydrogel) on articulating surfaces associated with 
induced arthritis in rabbit's TMJ. Subjects and methods: , fifty rabbits were employed. 
A technique to induce arthritis was performed on forty rabbits using a double IA injection 
of CFA. There were made five groups of rabbits. 10 rabbits in Group I (the normal group) 
and 10 in Group II (the arthritic group) did not receive any treatment, respectively. 
Ten animals each got a bilateral IA injection of 0.2 ml of Group III hyaluronic acid 
hydrogel.10 rabbits each got a bilateral IA injection of 0.2 ml of Group IV and bone 
marrow stem cell condition media.10 rabbits were given bilateral IA injections of 
0.2ml of a combination therapy (hyaluronic acid hydrogel and bone marrow stem cell 
condition medium (Group V). After the fourth week of injection-based therapy, all 
rabbits will be anesthetized then euthanized. Dissection, decalcification, and preparation 
Aim: To assess hyaluronic acid hydrogel /bone marrow stem cell-conditioned 
medium (MSC-CM with HA hydrogel) on articulating surfaces associated with 
induced arthritis in rabbit's TMJ. Subjects and methods: , fifty rabbits were employed. 
A technique to induce arthritis was performed on forty rabbits using a double IA injection 
of CFA. There were made five groups of rabbits. 10 rabbits in Group I (the normal group) 
and 10 in Group II (the arthritic group) did not receive any treatment, respectively. 
Ten animals each got a bilateral IA injection of 0.2 ml of Group III hyaluronic acid 
hydrogel.10 rabbits each got a bilateral IA injection of 0.2 ml of Group IV and bone 
marrow stem cell condition media.10 rabbits were given bilateral IA injections of 
0.2ml of a combination therapy (hyaluronic acid hydrogel and bone marrow stem cell 
condition medium (Group V). After the fourth week of injection-based therapy, all 
rabbits will be anesthetized then euthanized. Dissection, decalcification, and preparation 
of the mandible for Masson's Tri-chrome staining. Results: Those different treatment 
modalities responded to osteoarthritis in different ways, with MSC-CM with HA 
hydrogel being regarded as the most effective treatment of induced temporomandibular 
joint osteoarthritis among the tested treatment modalities. Conclusion: It was possible 
to conclude, within the limitations of the current study, MSC-CM with HA hydrogel 
being regarded as the most effective treatment of induced temporomandibular joint 
osteoarthritis