6.4. Future prospects of clinical use of BMP

It seems that although there are some promising results with BMP in clinical use, certain problems still persist. One of the problems is the optimal delivery system for BMP, which remains to be found. Also, there has been variation in the results, as some patients have not responded at all to BMP implants (Geesink et al. 1999, Groeneveld 1999). These results suggest that certain factors, which are currently unknown, negatively affect the BMP-dependent bone induction process in humans (Groeneweld & Burger 2000). The dosage of BMP has been under discussion, especially with regard to recombinant BMPs, as the costs of the required milligram doses might be a limiting factor in clinical use, as well as unexpected biological sequelae (Schmitt et al. 1999). Many questions remain to be answered before BMPs can be introduced into wider clinical use.