Human temporomandibular joint morphogenesis.

Temporomandibular joint morphogenesis was studied. Ranging in age of fetuses examined was from 6 to14 weeks' gestation. Our results showed the condyle so first element that appear between 6 degrees and 8 degrees week (condylar blastema). After a week appear temporal elements. Disk appear at the same time of glenoid blastema and it reaches an advanced differentation before of the condyle and temporal element, so these don't effect machanical compression on mesenchyma where we find the disk. So we think that the disk result of genetic expression and it isn't the result of mechanical compression. The inferior joint cavity appear to 12 week. The superior joint cavity appear to 13-14 week. In conclusion, the appearance of the condyle is the first event during TMJ morphogenesis, with its initial bud, in form of a mesenchymal thickening, becoming detectable between the sixth and eight week of development, when all the large joints of the limbs are already well defined.