Cartilage, function and craniofacial morphogenesis.

Abstract

While primary cartilage of the craniofacial complex is a derivative of the chondroskeleton, secondary cartilage develops in close association with membrane bone. Mobile function, motility, is not always a prerequisite for the genesis of secondary cartilage but seems necessary for its maintenance as also, evidently, is mechanical load. Both primary and secondary cartilage have active morphogenetic potentials. For the primary cartilage this potential is essentially instrinsic, as has been demonstrated with transgenic mice, for instance. Consequently, primary cartilage is less adaptive to external influences than secondary cartilage. Analysis of the factors controlling the growth of the cartilaginous structures renders their utilization in reconstructive surgery more predictable.