Revolutionary advances are underway that will dramatically change our understanding of periodontal diseases. The phenomenal progress being made in biomedical research is in large part fueled by advances in our overall knowledge of the human genome, development of microarray technology that allows comprehensive and unbiased evaluation of global biologic pathways and networks and expanded computational abilities. Expectations are all the periodontists will be affected by advances in molecular medicines, which in turn promises to lead to more accurate diagnosis, effective disease monitoring and development of targeted and specific therapies. Present review provides a brief overview to discuss the basic concept for understanding the potential of microarray technology in periodontal diseases.