Dental implants, with the appropriate suprastructure, are becoming an increasingly popular treatment option for partial and / or complete edentulousness. Many factors can influence osseointegration and therapy success, and this paper lists the latest research on the impact of systemic and local conditions on therapy success and offers guidelines in addressing these conditions. The correct criteria in selecting a patient for implant-prosthetic therapy should largely include patients with excellent oral hygiene, without a background of certain periodontal diseases, and patients without significant systemic diseases and chronic patients on systemic therapy. By collecting detailed medical history, we will find out all the relevant factors that may affect treatment. Systemic health should be good enough to withstand both the surgical part and prosthetic therapy. Special care should be taken in patients with diabetes because these patients have a higher risk of developing periimplant diseases, as well as in patients on bisphosphonates due to the risk of unsuccessful osseointegration and in patients receiving radiotherapy or chemotherapy. Smokers are twice as likely to have implant failure, similar with patients diagnosed with periodontitis. Good oral hygiene and a thick gingival phenotype with a sufficient amount of available bone are some of the local factors that can positively affect the success of therapy. By detailed extraoral and intraoral examinations and detailed analysis of three-dimensional X-rays, it is possible to develop a plan that will give optimal results, conduct therapy in a predictable and successful way and thus provide satisfaction to both therapist and patient.