Comparing Cobalt-Chromium Versus PEEK Secondary Telescopic Crowns on Implant Retained Mandibular Overdenture.

"implant retained mandibular overdenture using telescopic attachment system. all the patients received 2 implants at the canine region bilaterally using sterelithographic guide , then healing period for 3 months for proper osseointegration , then digital intraoral scanning was performed to detect implant position using scannable bodies , abutments which act as primary crowns were designed on cad software then milled using premilled titanium abutments.the study grouping was performed then virtual model was done for the designing of the frameworks then milled according to the grouping of the study. Try in of the frameworks was done and overdentures were inserted.~* Retention force test was done using digital force gauge.~* Probing depth using Teflon coated periodontal probe.~* Marginal bone level and bone density were measured using digital periapical x-ray"