Prognosis is an anticipation of the probable response to periodontal therapy and a long-term prospect for maintaining a functional dentition. Hopeless cases or cases of simple gingivitis without systemic diseases generally have little problem to establish definite prognoses. However, it might become somewhat challenging to determine their prognoses in borderline cases. A risk factor for periodontal disease may be environmental, behavioral, or biologic factors that can be defined as an occurrence has been associated with destructive periodontitis. Some risk factors are modifiable, while others cannot be modified. Modifiable risk factors are environmental or behavioral in nature in contrast non-modifiable risk factors are usually intrinsic to the individual and therefore not easily changed. In this review, we will assess the various modifiable or non-modifiable risk factors for susceptibility 10 periodontal diseases.