This article considers the outcomes of condylectomy with and without temporalis interposition as a method of treatment for severe degenerative disease and ankylosis. In the same issue, Sidebottom and Salha 1 Sidebottom A.J. Salha R. Management of the temporomandibular joint in rheumatoid disorders. Brit J Oral Maxillofac Surg. 2013; 51: 191-198 Abstract Full Text Full Text PDF PubMed Scopus (63) Google Scholar report the use of alloplastic total TMJ devices in the successful management of arthritic TMJ disease. They state: “Discectomy…may be supplemented with interpositional grafts, but there is no sound evidence of benefit (temporalis interpositional grafts may restrict opening because of scarring)…” Further, “When symptoms are caused by failure of the joint the final treatment for all degenerative, ankylotic, and collapsed joints is total replacement.”

Background: The efficacy of recombinant growth factors in vivo is highly dependent on the delivery vehicle. The authors investigated the osteoinductive effects of recombinant human bone morphogenetic proteins (BMP)-2 implanted together with a complex of heparin and chitosan. Methods: Sixty rats were used. Three different carriers in gel formulation (type I collagen, heparin/type I collagen, and heparin/chitosan) were mixed with either 0, 10, or 50 &mgr;g of BMP-2, making the number of groups nine. The gels were injected into the quadriceps muscles of both legs in 45 rats (n = 10 per group). Freeze-dried formulations of the carriers were also tested with the same amounts of BMP-2 using 15 rats (n = 5 per group). Four weeks after implantation, the quality and amount of newly formed bone were assessed. Results: Chitosan was shown to protect the heparinase-mediated degradation of heparin in vitro. The osteoinductive effects of BMP-2 in combination with heparin/chitosan were superior as compared with BMP-2 implanted together with type I collagen. Interestingly, the heparin/chitosan complex induced a small amount of bone also without BMP-2 added. The heparin/chitosan was completely absorbed after 4 weeks as determined by histologic evaluation, and a normal active bone formation was present. The freeze-dried formulations of the carriers demonstrated similar osteoinductive effects as the gels. Conclusions: An osteoinductive formula for clinical use is needed for general bone reconstruction. Heparin in complex with chitosan has the ability to stabilize or activate the growth factor in vivo and induce the generation of new bone in good yields.

Osteoinductive bone morphogenetic proteins (BMPs) may be used in humans to facilitate healing of bony defects. The effect of different BMPs is, as with many other growth factors, highly dependent on the delivery vehicle. Bovine type I collagen is currently used in the clinical setting as a carrier and has been approved in several countries for human use. Here, we report the reconstruction of a frontal bone defect using heparin together with bovine type I collagen, hyaluronic acid, and fibrin as vehicles for BMP-2. A bony structure was created on the back of the patient by treating the latissimus dorsi muscle with the growth factor. A polyamide mold was used as a template to achieve the desired shape. The bone structure was transplanted into the defect site via microsurgical techniques. Although the prefabricated bone was not large enough tocover the entire frontal defect, the reconstruction was completed by using an additional cranial implant.

Preoperative planning of complex osteotomies in craniomaxillofacial surgery, in conjunction with a surgeon's expertise, is essential for achieving an optimal result. However, the soft tissue changes that accompany facial bone movements cannot yet be accurately predicted. Bony tissue, because of its greater density, can be better predicted, but it alone does not account for the final aesthetic result. A new approach using not only three-dimensional (3-D) surface models of the patient's anatomy, but also a corresponding volumetric model, is discussed. This 3-D planning software was used in the treatment of 15 patients and was found to provide a good correlation between simulation and postoperative outcome.