The aim of this randomized control trial was to compare abutment teeth mobility and gingival health between digitally designed and produced poly ether ether ketone (PEEK) & metallic partial dentures (PDs) in mandibular Kennedy class I cases. Materials and methods: This study included 24 patients who were partially edentulous with mandibular bilateral free end saddles intended to receive a PD. They were randomly divided into 2 groups; a one to receive a computer aided designed (CAD) PEEK PD as the test group, and the other to receive a CAD metallic PD as the control group. Comparison was made between both groups regarding abutment teeth mobility measured by periotest as well as the periodontal health of the abutments in form of probing depth, gingival index and bleeding on probing. Results: Mobility values, probing depth, gingival index and bleeding on probing of abutment teeth in both groups were similar with no statistically significant difference. Conclusion: Both PD framework materials are considered acceptable with no preference regarding abutment teeth mobility and periodontal health