Introduction: Ridge split techniques were advocated to provide the necessary ridge foundation for implant replacement. Ridge split can be done by closed ridge splitting (minimum flap reflection) and open ridge splitting (full thickness flap reflection). Implant stability is a prim requisite for implant success. Material and methods: Ten male patients were randomly allocated to two groups. In Group I, five patients received simultaneous implant placed in open ridge split flap reflection. In Group II, Five patients received simultaneous implant placed in closed ridge split without flap reflection. Resonance frequency analysis was carried out to assess primary stability of the placed implants immediately after surgery. Results No significant difference in primary implant stability was detected between the closed and open ridge split techniques.Conclusion Open and closed ridge split techniques did not affect primary implant stability.