Purpose: The placement of dental implants in a distal RPD extension provided more stable and reliable occlusion. The target of this trial was to investigate the degree of correlation between the maximum biting force and surface electromyography of masseter fibers and anterior fibers of temporalis in two different implant positions in lower Kennedy class I
Material and methods : Fourteen patients having lower Kennedy class I with the first premolar as the last abutment and completely dentulous maxilla were randomly divided into two equal groups to receive implant supported partial overdenture. Each group received posterior bilateral two implants in the second molar area in the first group, while the group 2 one in the second premolar area. Right and left Maximum biting force was measured for both groups using I loadstar sensor and masseter and anterior temporalis muscle activity were evaluated with Surface Electromyography
Result : The data revealed that group I had significant positive correlation between maximum biting force and the masseter and anterior temporalis muscles activity in both the right and the left side with r value (1 , 0.79 , 0.89 and 0.75) respectively on the other hand the group II showed no significant positive correlation with r(0.04,0.01.-0.04 and -0.11) respectively
Conclusion : Within the limitation of this clinical trial, it was concluded that there were better muscle coordination between the two largest muscles of mastication (masseter and temporalis) and the produced biting force as a product due to installation of posterior implant in the lower second molar area.