Comparative twin study in elderly: Relationship between oral status and environmental status

本研究的目的是检测个体口腔健康的遗传性，包括牙齿脱落，咀嚼能力，形态学特征。颌骨的长度或宽度等形态学特征有遗传倾向。但是，牙齿的脱落很大程度上受环境因素的影响。咀嚼能力有遗传和环境两方面的因素。这些结果对于牙医和患者预防牙齿状况恶化以及认识到治疗的局限性都很重要。第二个目的是评估考虑遗传因素的剩余牙齿数量与动脉硬化之间的关系。从我们的研究来看，它们之间的联系与遗传有关。即使在排除了这种基因混杂之后，它们之间仍然存在显著的关联。因此，牙齿脱落被认为是影响动脉硬化的重要环境因素。

The purpose of this study was to detect the heritability of the individual oral health, including tooth loss, ability of chewing, morphologic figures. Morphologic figures such as length or width of the jaw have genetic predisposition. But, loss of teeth is greatly influenced from environmental factors. And the ability of chewing has both aspects of genetic and environmental factors. These results would be important for both dentists and patients to prevent compromised dental condition, and to recognize the limit of the treatment.Second aim was to assess the relationship between number of remaining teeth and arterial sclerosis considering genetic factors. From our study, there was a genetic contribution to the association of them. And even after eliminating such a genetic confounding, there was a significant association of them. Therefore, tooth loss would be considered as an important environmental factor to affect arterial sclerosis.