並列摘要
The health of periodontium and the success of a prosthodontic treatment are intimately related. Jeopardized by untreated periodontal disease, the functions, esthetics and the prognosis of a restoration will be compromised. A poor restoration may have adverse effects on the periodontium by increasing accumulation of the dental plaques. Violation of the biologic width can lead to the deterioration of periodontal support and compromise the long term success of a restoration. Improper placement of the margin in the cervicular area or the presence of overhanged margin can influence the ecology of the subgingival area by changing the bacterial flora. Therefore, a thorough periodontal consideration before prosthodontic reconstruction is indispensable. This article discusses the significance of the concept of biologic width, the interaction between the periodontal tissue and the restorations. The current crown-lengthening procedures and the related important factors in selecting the operation are also covered.