Abstract:

Objective　To study the role of Ca2+overload and energy metabolism in mitochondria in masticatory muscle dys- functional induced by occlusal trauma.Methods　Mitochondrial Ca2+contents were measured with atomic emission spectropho- tometer. Mitochondrial ATP and ADP contents were measured with high performance liquid chromatography.Results　①Mito- chondrial Ca2+contents of masseter muscle ipsilateral to mental splint in ten and twenty days′experimental groups and that con- tralateral to mental splint in twenty days′experimental group increased significantly (P<0.05).②Mitochondrial ATP contents of masseter muscle ipsilateral tomental splint in experimental groupswere higherthan that in control groups and contralateral tomen- tal splint after twenty days.③Mitochondrial Ca2+contents of masseter muscle ipsilateral to mental splint were significantly nega- tively correlated tothe mitochondrial ATP contents(r=-0.780,P<0.05).Conclusion　Ca2+overload inmitochondria depress- es ATP production, which results in energy metabolism disorder in masticatory muscle cells. It may play an important role in the mechanism that occlusal trauma results in masticatory muscle dysfunction.

Key words: occlusal trauma, masticatorymuscle dysfunction, calcium, adenosine diphosphate, adenosine triphosphate