Aim: The study aimed to compare the retention of unilateral attachment retained RPD with cross-arch stabilization versus not crossing the arch. Retention was measured using the Universal Testing machine.
Methods: Mandibular epoxy model simulating unilateral free end saddle case with missing right first and second molars was used. The right first and second premolars were prepared to receive surveyed crowns with attached patrices of “rk-1 uni" attachment. Two metal-framework designs were made with matrices of “rk-1 uni" attachment casted to it. The intervention group design was a unilateral PD, while the control group design used double Aker clasp on the dentate side for cross-arch stabilization. A ready-made hook was attached at to the geometric center of each group to help in retention measurement process. Measurements were done initially, after 500, 1000, 1500 & 2000 insertion/removal cycles which simulate 2 years of use by the patient, at a speed of 0.5 mm/min,.
Results: Statistically significant difference was found between retention of both designs (p < 0.001). The control group showed higher retention than the intervention group. Both groups lost retention over time. Retention increased again after 1500 cycles. After completion of 2000 cycles, the control group showed higher retention than the intervention group.
Conclusion: Both dentures had initial acceptable retention force above 5 N, yet the denture with cross-arch stabilization showed superior retention than the unilateral denture after 2000 cycles. The unilateral partial denture design lost more retention than the partial denture with cross-arch stabilization.