Purpose: This research investigated the effect of two nylon inserts for the locator attachment
with different retentive values on oral rehabilitation for the patients wearing mandibular overdenture
regarding their muscular activity.
Materials and methods: Six complete maxillary and mandibular overdentures were delivered
to six healthy male patients. Two implants were installed in the canine region via computerized
surgical stent. The mandibular overdentures were retained by locator attachment.
Grouping of the study were done according to the used retentive nylon insert of the locator
attachment
Group 1: All the patients used blue nylon inserts for three months
Group 2: the same patients used pink nylon inserts for another three months, with one month
rest period interposed between the used blue &pink nylon inserts .
The impact of these types of nylon inserts on the activity of masseter & temporalis muscles was
investigated via electromygraphic analysis.
Results: ANOVA test revealed improvement for all patients in tested muscles activity expressed
as EMG records considering amplitude of these muscle during clenching and chewing hard &soft
food either for blue or pink nylon inserts with statistical significance between different measuring
periods. Paired t-test proved that pink insert provides significant improvement in muscular activity
than the blue one at p ≤ 0.05.
Conclusion: Depending on the investigation of this study , it be concluded that the retentive
system used in the locator attachment has great impact on oral rehabilitation regarding the patients'
muscular activity.