تکامل مفصل گیجگاهی آرواره ای در جنین رات با تأکید بر نحوه ایجاد حفره مفصلی

ABSTRACT Many studies have been Carried out on the development of synovial joints, and researchers have provided various evidence about factors involving in the cavity formation. The Purpose of this study is to investigate the factors which incorporate in the cavity formation in the mandibular joint, 17 rat embrioes (16-20 days of gestation) were employed. After serial section, specimens were stained by methods of H & E, Toluidine blue, Alcian Blue, Phosphatae acid and then studied by light microscope. Our results possibly indicate that metachromatic materials rather than the cell death phenomenon are involved in cavity formation. It has previously been reported that muscle contraction plays an important role in cavity formation, however, our microscopic observations are in concordance with this fact. The inferior cavity formation is exceptional in that it will be formed just after separation of joint disc from the condylar surface. It also appears that blood vesseles play a significant role in the inferior cavity formation in this joint.