JAW-CLOSING MUSCLES - ELECTROMYOGRAPHIC ACTIVITY OF HUMAN-SUBJECTS WITH REDUCED PERIODONTAL SUPPORT

The aim of this study was to compare the electromyographic (EMG) activ ity of jaw-closing muscles of individuals with normal and reduced peri odontal bone support. Fourteen adult subjects with more than 24 remain ing teeth and low levels of periodontal inflammation, were selected fo r the study. Subjects of the control group had 90% of the periodontal bone support left, while other subjects presented a reduction of 52% o f the original periodontal bone. Chewing experiments were performed us ing silicone tablets, carrots and white bread. The EMG of masseter and anterior temporal muscles was performed bilaterally, using bipolar su rface electrodes, and the EMG amplitude was full wave rectified, integ rated and the area extension under the curve was used to access muscle activity. The results of the chewing experiments did not show any sta tistically significant difference in the EMG activity of the study gro ups, irrespective of the chewing stuff. The height of periodontal bone support did not seem to influence the electroactivity of jaw-closing muscles, indicating that reduced periodontal support might equally be able to withstand masticatory loads. Hence, individuals with reduced p eriodontal bone support revealed a similar EMG activity compared to su bjects with normal periodontal bone support.