Effect of estrogen and dietary loading on condylar cartilage.

Aims: To study the effect of estrogen deficiency and altered temporomandibular joint loading on the histomorphology of condylar cartilage and on the expression of types II and X collagen and matrix metalloproteinase-3 (MMP-3).

Methods: Thirty-six female rats were divided into four groups: ovariectomized rats on a normal diet, nonovariectomized control rats on a normal diet, ovariectomized rats on a soft diet, and nonovariectomized control rats on a soft diet. Ovariectomy was performed at the age of 60 days.

Effect of estrogen and altered diet hardness on the expression of estrogen receptor alpha and matrix metalloproteinase-8 in rat condylar cartilage.

Aims: To examine the effect of decreased estrogen level and altered diet hardness on condylar cartilage morphology of the rat temporomandibular joint (TMJ) and on the expression of condylar cartilage estrogen receptor alpha (ERa) and matrix metalloproteinase-8 (MMP-8).

Methods: A total of 36 female rats was divided into four groups: ovariectomized rats fed a normal diet, non-ovariectomized controls fed a normal diet, ovariectomized rats fed a soft diet, and non-ovariectomized controls fed a soft diet. Ovariectomy was performed at the age of 60 days.

Effect of diet hardness on mandibular condylar cartilage metabolism.

Aims: To study the effect of diet hardness on condylar cartilage thickness, extracellular matrix composition, and expression of matrix metalloproteinase (MMP) -3, -8 and tissue inhibitor of metalloproteinase-1 (TIMP-1), by using immunohistochemical and morphometric methods.

Methods: Seventy-two female Sprague Dawley rats were exposed to different dietary hardness, from soft to hard. MMP -3, -8, and TIMP-1 expression, cartilage thickness, cell count, and expression of type II collagen were studied.

Dietary loading and aggrecanase-1/TIMP-3 expression in rat mandibular condylar cartilage.

Aims: To examine the expression of aggrecanase-1 and a tissue inhibitor of metalloproteinases (TIMP-3) in the condylar cartilage of young rats and to determine their relationship during altered dietary loading at different time points after weaning.

Methods: One hundred Sprague-Dawley rats were randomly assigned to 1 of 2 groups: the soft-diet group, which served as the control group (n=50), or the hard-diet group, which served as the experimental group (n=50). Ten soft- and 10 hard-diet rats were killed at 6 hours, 12 hours, 24 hours, 48 hours, and 9 days after weaning (i.

MMP-3 and -8 expression is found in the condylar surface of temporomandibular joints with internal derangement.

Background: Internal derangement is one of the most common disorder of the temporomandibular joint (TMJ). The aim of this study was to investigate the associations of matrix metalloproteinase (MMP)-3 and -8 expression in articular condylar surface with different stages of TMJ internal derangement according to Wilkes (Minn Med, 1978; 61: 645-52) and osteoarthrosis (OA) according to Dijkgraaf et al. (J Oral Maxillofac Surg, 1995; 53: 1182-92).