Aim: This prospective clinical study aimed to evaluate and compare the effect of primary stability on osseointegration and success rate of four different implant systems. Material and Method: Eighty implants were placed on the maxillary and mandibular arch of 45 patients. The four implant systems used in this study were Straumann SLA bone level implants, BIOMET 3i OSSEOTITE, Astra Tech Dental (OsseoSpeed) Implant System, and Nobel Replace Conical Connection implant system. A two-stage implant placement procedure was followed. During the implant placement, maximum insertion torque was recorded. The implant stability quotient (ISQ) was also recorded using Ostell, which was further assessed using resonance frequency analysis (RFA). Descriptive data were analyzed using median and percentage. For Pairwise Comparison, the Shapiro-Wilks Rank Sum test was utilized. The p-value was set to 0.05 for all the measurements. Results: The insertion torque value was similar among all four implants. All the implants have almost similar ISQ values post-surgery. However, Nobel and 3i implant systems showed a lower ISQ value in the second and third quartile. Kruskal Wallis Rank Sum Test showed that the distribution of ISQ in all directions was not the same across all Implant systems (Chi-square=21.588, df=3, p-value = 0.001). The success rate of Straumann and Astra was 100%, while Nobel and 3i were 90% and 80% respectively. Conclusion: Primary stability has no effect on osseointegration and implant success rate. Moreover, Ostell device was found to be a significant predictor for implant osteointegration after successful placement and healing of dental implant site.