Abstract
The purpose of this study was to investigate the influence of periodontal disease on masticatory function and the effect of periodontal therapy on it. Nine patients with mild to advanced periodontitis were. examined about masticatory efficiency, maximum bite force, occlusal platform area, width of keratinized gingiva and the position of gingival margin in addition to routine clinical examinations. Masticatory efficiency was measured by modified Ishiwara's method on right and left halves of dentitions with raw rice as test food. After the periodontal treatment, these measurements were performed again on five patients.
The results were as follows:
1) The average scores of Plaque Index, masticatory efficiency and maximum bite force were 1.54, 86.3% and 29.1Kg respectively.
2) Before treatment, there was a significant negative correlation between masticatory efficiency and bone resorptioq (P<0.01), tooth mobility (P<0.01) and pocket depth (P<0.05), on the other side a significant positive correlation between masticatory efficiency and maximum bite force was found.
3) After periodontal treatment, average masticatory efficiency increased (34%) but this change was not statistically significant (P>0.05).
4) After treatment, increase of maximum bite force and occlusal platform area was found, and decrease of tooth mobility, bone resorption, Gingival Index score and pocket depth was observed, and gingival margin was apically shifted. Above changes were all significant at the 1% level of confidence.
