BACKGROUND:
Although various commercially available filler materials are now commonly used, their variable degrees of resorption require repeated percutaneous injections. To overcome these drawbacks, a new injectable in vitro differentiated adipocyte filler has been developed, and animal studies have demonstrated that implantation of the filler successfully enhances in vivo adipose tissue formation. This study was undertaken to evaluate the clinical efficacy of this method, particularly in soft tissue augmentation.

MATERIALS AND METHODS:
Autologous adipose-derived stromal cells were isolated, cultured, and differentiated to adipocytes in vitro. The differentiated adipocytes were suspended in Dulbecco's modified Eagle medium and injected into the lesion requiring soft tissue augmentation. Eight patients were treated with this tissue-engineered filler. Long-term follow-up for longer than 1 year was possible in all patients.

RESULTS:
Two or 3 weeks after the injection, volume increment of subcutaneous tissue was observed around the injection area in the ensuing 1 to 5 weeks. Thereafter, additional volume augmentation was not found and the augmentation effect was well-maintained. All patients agreed on the clinical effectiveness of the procedure, and no complications occurred.

CONCLUSIONS:
The results obtained indicate that this method is well tolerated and may be an effective means of achieving soft tissue augmentation. The authors have indicated no significant interest with commercial supporters.