Introduction: A well-constructed two-implant-assisted mandibular overdenture can be a successful treatment option for completely edentulous patients as it helps improving the oral function and patient satisfaction through elimination of the fear of dislodgment during speech or mastication. Various attachment systems can be used for retaining mandibular overdentures such as bar, ball and socket, OT equator and locators. A new attachment system with metal to metal interface named Titach has evolved. During mastication, loads are transferred to alveolar bone surrounding the implants.
Objectives: This study was done to compare the stress transmitted to peri-implant tissues of implant-assisted mandibular overdenture using two different attachment designs; Titach attachment and locator attachment.
Materials and methods: A completely edentulous epoxy resin mandibular model was used in which two parallel dental implants were inserted at the canine region bilaterally. Sixteen mandibular implant-assisted overdentures were constructed forming two groups; each with different attachment design. Group I received 8 pairs of Titach attachment, while group II received 8 pairs of locator attachment. The difference in stress distribution was measured using strain gauges and compared between the two studied groups. Vertical load and oblique load (30^o and 45^o) of 50 and 100 N using the universal testing machine were applied bilaterally on the central occlusal fossae of mandibular first molars.
Results:There was no significant difference between group I and II upon application of vertical loading 50, 100N and 30^o oblique loading 50 N. However, group I showed lower strain values upon application of 30^o oblique loading 100N, 45^o oblique loading 50N and 100N.
Conclusions: Titach attachment with metal to metal interface showed less strain values with favourable stress distribution when compared to zest anchor locator attachment with nylon interface for implant-assisted mandibular overdenture.