Introduction: Utilization of removable partial dentures (RPD) is inevitable in some patients that are not indicated for any other treatment option, however the cases of distal-extension removable partial dentures (RPDs) are associated with several problems. Because Kennedy class II is a tooth tissue supported so there is a difference in the degree of resiliency between tooth and tissue which cause a difference in the viscoelastic responses. This also may lead to a rotational movements of RPDs that might produce excessive torque forces against the abutment teeth and the soft tissue. The incorporation of Telescopic crown retained removable partial denture is one of the options which provides satisfactory support and preservation of the supporting structures. t
Materials and methods:10 acrylic mandibular model Kennedy class II were constructed upon this model , two experimental telescopic overdentures were fabricated as follows: Group A unilateral tooth supported telescopic retained removable partial over denture. Group B unilateral extracoronal attachment retained RPD,

Result: the result revealed that there was insignificant difference as P-value > 0.05 between the two different groups
Conclusion: unilateral partial denture can be used with telescopic retainer or extracoronal retainer without inducing a lot of stress over the supporting structures