CALLUS DISTRACTION

Fibroblast networks that form collagen and connect the two ends of bon e develop in the haematoma after corticotomy. This regenerative tissue is vascularized and distracted. Even during the lengthening, minerali zation starts. This starts at the ends created by the osteotomy, in th e form of conical bony columns 200 mu m thick, which grow towards each other in a manner reminiscent of stalagmites and stalactites, until t he central, fibrous inner zone (growth zone) formed during distraction is completely mineralized. Connective tissue and bony bars are arrang ed lengthwise. As a rule, intramembranous callus formation takes place during distraction osteogenesis with no intermediate cartilaginous st ep.