For natural dentition to function optimally, the supporting tissues should be in healthy state. So as a clinician we must strive to recognize and eliminate as many pathological factors as possible before undertaking any therapeutic procedures, whether operative, endodontic, orthodontic or prosthodontic. If the existing oral disease is unrecognized or disregarded prior to the start of dental therapy, it may be aggravated by the therapeutic procedure itself.The practice of restorative dentistry has a reciprocal relationship with maintenance of periodontal health. The marginal periodontium is where the fields of restorative dentistry and periodontics overlap. This interdependence can be understood only when there is agreement upon what constitutes a healthy periodontium and how a pathological condition can be corrected and prevented. The tooth and its surrounding structures are continually challenged by microbial flora, and restorative dentistry may exacerbate this challenge.