Waerhaug J
Scand J Dent Res. 1975 Jul;83(1):193-201. doi: 10.1111/j.1600-0722.1975.tb00428.x.
One hundred and eight extracted teeth with restorations placed below the gingival margin were stained and examined under the stereomicroscope with the aim of scoring presence or absence of subgingival plaque. Individual observations showed that a subgingival restoration can be completely covered with plaque in as short a time as 6 weeks and it can be free of plaque for as long as 2 years. In the material as a whole about 9 out of 10 of the restorations were covered with plaque subgingivally. Since the material is selected, these proportions cannot be claimed to be valid for the population as a whole, but the observations suggest that plaque sooner or later will accumulate on most if not all subgingival restorations. Rough surfaces and or inadequate marginal adaptation are likely to facilitate a more rapid adherence of bacteria to the restorations than to the smooth tooth surface. It is concluded that restorations placed below the gingival margin indirectly are stongly involved in the etiology of destructive periodontal disease and the cause of many extractions.
对108颗龈缘以下有修复体的离体牙进行染色，并在体视显微镜下检查，目的是对龈下菌斑的有无进行评分。个体观察表明，龈下修复体在短短6周内就可能被菌斑完全覆盖，也可能长达2年都没有菌斑。在整个材料中，约十分之九的修复体龈下有菌斑覆盖。由于该材料是经过挑选的，这些比例不能声称对总体人群有效，但观察结果表明，大多数（如果不是全部）龈下修复体迟早会有菌斑积聚。粗糙表面和/或边缘适应性不足可能比光滑牙面更易促进细菌更快地附着于修复体。结论是，间接放置在龈缘以下的修复体在破坏性牙周病的病因中起重要作用，也是许多拔牙的原因。
