Copyright © American Speech-Language-Hearing Association From: The Application of Tissue Engineering Procedures to Repair the Larynx J Speech Lang Hear Res. 2006;49(1):194-208. doi:10.1044/1092-4388(2006/016) Legend: (A) Typical appearance of thyroid cartilage from unoperated hemilarynx and (B) changes in cartilage were characterized by vascularization of the interior of the cartilage into bone by endochondral ossification (10× original magnification). (C) Extensive endochondral ossification of STM 24-week thyroid cartilage (note formation of bone with typical Harversian-like canals and lamellae of bone; 10× original magnification) and (D) a higher magnification (20× original magnification), illustrating the mechanism of vascular bud invasion into cartilage resulting in bone formation. Changes in cartilage matrix preceding boney transformation are evident. Appearance of 24-week thyroid cartilage (E) illustrating the typical appearance of the remodeled cartilage (note the region of perichondrium, the area of new bone formation, and the typical appearance of hyaline cartilage which has not yet become ossified) and (F) illustrating a vascular bud originating from the perichondrium, which has caused ossification within parts of the cartilage and is creating local changes in neighboring areas. These include hypertrophy of chondrocytes and changes in cartilage matrix, which precede transformation of cartilage into bone (40× orignal magnification). (Masson trichrome stain.) Date of download: 10/17/2017 Copyright © American Speech-Language-Hearing Association