Valderhaug J, Heloe L A
J Periodontol. 1977 Apr;48(4):221-4. doi: 10.1902/jop.1977.48.4.221.
The oral hygiene, the gingival condition, pocket depth, and the incidence of caries on crowned teeth were studied during a period of 5 years in a group of patients (114) who had been treated with fixed dental prostheses. Prior to the prosthetic treatment, the patients received periodontal treatment. During the study, the subjects participated in an oral hygiene program. Crown margins were located sub-gingivally, at the gingiva and supra-gingivally. When the crown margins were located sub-gingivally, there was an increase in Gingival Index scores 2, and in pocket depth, compared to supra-gingival placement. An improvement of gingival health was recorded where the crown margins were located supra-gingivally. Caries lesions developed on 3.5% of the tooth surfaces which had recieved crowns.
对一组接受固定义齿修复治疗的114例患者进行了为期5年的研究，观察其口腔卫生状况、牙龈情况、牙周袋深度以及戴冠牙齿的龋病发生率。在进行修复治疗前，患者接受了牙周治疗。研究期间，受试者参与了口腔卫生计划。冠边缘位于龈下、龈缘处及龈上。与冠边缘位于龈上相比，当冠边缘位于龈下时，牙龈指数评分增加2，牙周袋深度增加。当冠边缘位于龈上时，记录到牙龈健康状况有所改善。在接受冠修复的牙齿表面，有3.5%发生了龋损。
