Histological Characteristics of Ligaments between Middle Ear and Temporomandibular Joint

OBJECTIVES To examine histological aspects of the ligaments between the middle ear and temporomandibular joint and suppose a theoretical role of their structural characteristics on mobility of mallear ossicle. METHODS The ligaments were obtained by microdissection of middle cranial fossa on both sites of 15 cadavers fixed in formalin solution and were sectioned longitudinally (7-10 mum thickness). The sections were stained with Verhoff's Van Gieson's stain (VVG) for demonstration of elastic fibers and visualized at X2.5 and X10 magnifications under light microscopy. RESULTS Anterior mallear ligament (AML) and sphenomandibular ligaments (SML) were consisted of collagen fibres in analyzed specimens. The discomallear ligament (DML) was constituted of rich collagenous fibres. One specimen of DML harvested between petrotympanic fissure and retrodiscal-capsular intersection site contained elastic fibers dispersed in cotton-bowl appearance between collagen fibers. In the light of functional tests performed in previous studies, it could be extrapolated that presence of elastic fibers in the DML may prevent excessive forces conducted to mallear head by elongation of elastic fibers. CONCLUSIONS Collagenous fibres have no ability to stretch along their axis which may lack compensatory mechanism to prevent mallear head mobility.