Chewing efficiency and electromyographic activity of masseter muscle with three designs of implant‐supported mandibular overdentures. A cross‐over study

Purpose The aim of this study was to compare the effect of three designs for implant‐supported mandibular overdenture on the chewing efficiency and electromyographic ( EMG ) activity of masseter muscles. Material and methods Eighteen edentulous patients received new maxillary and mandibular dentures (control, CD ) before implant placement. After using the dentures for 3 months, patients were randomly divided into six blocks (three patients/block) and received four implants in canine and first molar areas of the mandible. Following osseointegration period, new duplicate mandibular overdentures were successively connected to the implants with: (i) ball attachment on two implants (2 BOD ), (ii) bar attachment on two implants (2 ROD ), and (iii) bar attachments on four implants (4 ROD ) in a random order. Chewing efficiency was measured using chewing gum, and EMG was recorded during clenching (with or without food). Evaluations were made 3 months after using each of the following prostheses: CD , 2 BOD , 2 ROD , and 4 ROD . Results All implant‐supported overdentures showed a significant increase in chewing efficiency and EMG values when compared to CD . These values increased significantly with 4 ROD when compared to 2 BOD or 2 ROD prostheses. There was no significant difference in chewing efficiency and EMG between 2 BOD and 2 ROD prostheses. Conclusion Four‐implant‐supported overdentures seem to present a functional advantage vs. two‐implant‐supported overdentures, independent of the chosen attachment system.