Development of functional soft denture liners without environmental endocrine disruptors

义齿软衬因其独特的粘弹性而被广泛应用于无牙颌患者。然而，近年来，一些软性义齿衬里中含有的环境内分泌干扰物(邻苯二甲酸酯)已成为社会问题。本研究的目的是研制无环境内分泌干扰的功能性义齿软衬。研究了酯类增塑剂的种类、聚合物和单体对软衬的粘弹性能、吸水率、溶解度和咀嚼功能的影响。用动态粘弹仪测定了6种材料的剪切储能模数(G‘)、剪切损失模数(G“)和损耗角正切(tanδ)。通过测量两个食物样本的最大咬合力、咀嚼次数和频率，并使用视觉模拟标尺来评估10名受试者的咀嚼功能。丙烯酸酯材料表现出粘弹性行为，而有机硅材料表现出弹性行为。研究发现，对于需要在义齿上提供软衬的患者，使用具有较高tan d和G‘的材料可以提供最佳的咀嚼功能。在移动显微镜下观察组织调节剂的线性尺寸随时间的变化，以及这些变化与重量变化的关系。2002年，研究了增塑剂(癸二酸二丁酯)与义齿基托树脂的粘弹性和粘附性的关系。这些结果计划在国际牙科研究协会第81届全体会议和展览上公布。

Denture soft liners mare widely used in edentulous patient by means of specific viscoelastic properties. However, recently environmental endocrine disruptors (phthalic esters) which are included in some soft denture liners are social problem. The purpose of this study is development of functional soft denture liners without environmental endocrine disruptors. Influence of type of ester plasticizer, polymer, and monomer on viscoelastic properties, water absorption, solubility, and masticatory function are evaluated.In 2001, relationship between dynamic viscoelastic properties of soft liners and masticatory function was studied. The shear storage modulus (G'), shear loss modulus (G") and loss tangent (tan δ) were determined for six materials using a dynamic viscoelastometer. Masticatory function of ten subjects was evaluated by measurements of maximum bite forces and chewing times and frequencies for two food-samples, and using visual analogue scales. The acrylic materials exhibited viscoelastic behavior, whilst the silicones exhibited elastic behavior. It was found that the use of materials with higher tan d and G' provides the most optimum masticatory function for patients requiring the provision of soft liners on their dentures. The linear dimensional changes with time of tissue conditioners using a traveling microscope and relationship between these changes and weight changes were evaluated. The absorption and solubility of these materials were also determined.In 2002, relationship between plasticizer (dibutyl sebacate), and viscoelasticity and adhesion to denture base resins were studied. These results are planed to be presented in 81th General Session and Exhibition of the International Association of Dental Research.