Premium
Effects of mechanical tension on matrix degradation by human periodontal ligament cells cultured in collagen gels
Author(s) -
Von den Hoff J. W.
Publication year - 2003
Publication title -
journal of periodontal research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.31
H-Index - 83
eISSN - 1600-0765
pISSN - 0022-3484
DOI - 10.1034/j.1600-0765.2003.00404.x
Subject(s) - collagenase , periodontal fiber , tension (geology) , matrix (chemical analysis) , zymography , matrix metalloproteinase , chemistry , extracellular matrix , biophysics , cell culture , biomedical engineering , materials science , ultimate tensile strength , composite material , dentistry , enzyme , biochemistry , biology , medicine , chromatography , genetics
Background: Periodontal ligament (PDL) cells are thought to play a crucial role in the remodelling of periodontal tissues during orthodontic tooth movement. Objective: The objective of this study was to analyse the effects of mechanical tension on matrix degradation by PDL cells cultured in collagen gels. Methods: The gels were prepared free‐floating or attached to the culture wells and cultured for up to 22 d. In free‐floating gels very little mechanical tension is generated within the matrix, whereas in attached gels tension is highly increased. Results: At d 8, free‐floating gels had contracted to 2% of their original wet weight. Attached gels had contracted to only 40%, but by d 15 all gels had spontaneously detached from the wells and had contracted rapidly. The collagen content of free‐floating gels had decreased to 30% of the initial value at d 22. Collagenase activity was detected in the culture media of the free‐floating gels and the presence of matrix metalloproteinases (MMPs) 2 and 9 was shown by zymography. In addition, histological sections showed matrix degradation around the cells. This shows that ligament cells in free‐floating gels are actively resorbing the collagen matrix. The collagen content of attached gels did not change during the first 8 d but, after detachment, it rapidly decreased to 2%. Therefore, mechanical tension seems to prevent degradation of the matrix. In contrast, relaxation of the tension enhances the resorptive activity. Conclusions: The sensitivity of PDL cells to mechanical tension may be essential for the remodelling of periodontal tissues and their adaptation to physiological and orthodontic forces.