• Petri Tiilikainen, Aune Raustia, and Pertti Pirttiniemi.
• J Orofac Pain. 2011 Jan 1; 25 (1): 68-74.

AimsTo 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.MethodsSeventy-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. Analysis of variance among treatments was carried out followed by Bonferroni's comparisons test.ResultsThe ratio of MMP-3 and TIMP-1 immunopositive cartilage cells were similar in all age groups, whereas the number of MMP-8 positive cells decreased with age. A change of diet from soft to hard caused a significant decrease in the number of MMP-3 and MMP-8 and an increase in TIMP-1 positive cells. Cartilage thickness and area of type II collagen-positive staining were significantly affected by diet hardness.ConclusionThe results show that a soft diet during growth increases collagenolytic activity and may increase the vulnerability of condylar cartilage.

27 keywords...

hide…