Aim and objectives: The present study was undertaken for assessing the prognosis of dental implants in diabetic, hypertensive and smokers. Materials & methods: A total of 20 diabetic, 20 hypertensive and 20 chronic smokers were enrolled in the present study. Another set of 20 healthy subjects who underwent dental implant procedure for missing mandibular first molar were enrolled. Oral examination was done and treatment planning was done. All the subjects underwent rehabilitation of missing mandibular first molar by dental implants. Implant procedures were carried out under local anesthetic procedures. Follow-up was done and prognosis of dental implants was assessed. All the results were recorded in Microsoft excel sheet. Results: Among diabetic groups, hypertensive group, smokers group and control group, success rate of dental implants was 90 percent, 85 percent, 75 percent and 95 percent respectively. Conclusion: Dental implants had excellent prognosis among diabetic and hypertensive patients. However; among smokers, their prognosis is significantly affected. Keywords: Implant, diabetes, hypertension, smoking