The purpose of this study was to show the effects of platelet rich fibrin (PRF) in the ridge splitting and expansion technique.Subjects and methods: Twelve patients recruited from the outpatient clinic of Oral Medicine, Diagnosis and Periodontology Department, Faculty of Oral and Dental Medicine, Cairo University. The patients were divided randomly into two equal groups were the control group received ridge splitting and expansion with simultaneous implants placement without application of platelet-rich fibrin (PRF) with simultaneous implant placement, while the study group did not receive PRF. Cone beam volumetric tomography (CBVT) was taken pre-operative, immediately post-operative (within the first 24 hours post-operatively) and after 6 months.Results: There was a statistically insignificant difference on mean bucco-palatal bone width between both groups at p=0.128 after 6 months evaluation, and at p=0.255 between immediate and 6 months evaluations. There was a statistically insignificant difference on mean buccal bone resorption between both groups at p=0.754 after 6 months evaluation, and at p=0.304 between immediate and 6 months evaluations. There was a statistically insignificant difference on mean palatal bone resorption between both groups at p=0.581 after 6 months evaluation, and at p=0.758 between immediate and 6 months evaluations. There was a statistically insignificant difference on mean mesial bone resorption between both groups at p=0.664 after 6 months evaluation, and at p=0.574 after 6 between immediate and 6 months evaluations. There was a statistically insignificant difference on mean distal bone resorption between both groups at p=0.403after 6 months evaluation, and at p=0.783 after 6 between immediate and 6 months evaluations..Conclusion: The results of the present study revealed that covering the osteotomy site using platelet-rich fibrin membranes following the ridge splitting and expansion procedure provided gain in bone width and decrease in crestal bone resorption although they are statistically non-significant.