Ortengren U
Dept. of Prosthetic Dentistry/Dental Materials Science, Faculty of Odontology, Göteborg University, Box 450 SE-405 30 Göteborg, Sweden.
Swed Dent J Suppl. 2000(141):1-61.
The aims of this thesis were: 1. To study the effect of water and pH on composite resin materials in vitro by assessing sorption, solubility, monomers eluted and flexural properties. 2. To study adverse effects on the skin in dentists possibly caused by acrylic resin-based materials.
Proprietary composite resin materials were used for the in vitro experiments. The tests were performed according to the ISO 4049 (1988) with the exception of McIlvaine's solution used in Study II and the storage times. The analysis of eluted monomers was performed using HPLC. The flexural properties were tested in a three-point bending equipment. The secant modulus and deflection at break were calculated for description of the viscoelastic behaviour of the material tested. To study the adverse effects on skin in dentists, a questionnaire was sent to 3500 randomly selected Swedish dentists. A response rate of 88% was achieved and the data were statistically analysed and compared with the results of two studies on skin symptoms among the general Swedish population. Dentists living in the three main cities in Sweden who had experienced hand eczema during the last 12 months were invited to a clinical examination in which a patch test was included.
A wide range in sorption and solubility over the test period was found, with low sorption values observed for materials containing hydrophobic matrix monomers. A maximum concentration of monomers eluted was found after 7 days of storage, and TEGDMA was the main monomer released. pH affected the sorption and solubility behaviour for two of the three materials tested. The flexural strength and modulus of the composite resin material were lowered after water storage and the secant modulus and deflection at break could describe the viscoelastic behaviour. The prevalence of dry skin and hand eczema was high in dentists compared to two age-matched general population samples investigated using identical questions. The most important predictor for adult hand eczema was found to be childhood eczema. At the clinical examination, irritant contact dermatitis was the predominant diagnosis. Seven per cent reported skin symptoms when working with acrylic resin-based material but the true prevalence of hand eczema caused by acrylates was below 1%. Contact allergy was diagnosed, however, in 50% of the dentists, mainly due to other allergens such as nickel, perfumes or rubber chemicals.
The matrix composition was shown to be important for the sorption and solubility behaviour of the composite resin materials tested and a maximum release of monomers occurred after 7 days of storage. pH affected the water sorption and solubility behaviour. Calculation of the secant modulus and the deflection at break allowed the plasticising effect of water on composite resin material to be observed. The prevalence of hand eczema was high among dentists, with irritant contact dermatitis as the predominant diagnosis. Childhood eczema was the most important predictor for adult hand eczema. The prevalence of hand eczema owing to acrylates was below 1%.
本论文的目的如下：1. 通过评估吸附、溶解性、洗脱单体和弯曲性能，在体外研究水和pH值对复合树脂材料的影响。2. 研究基于丙烯酸树脂的材料可能对牙医皮肤产生的不良影响。
使用专利复合树脂材料进行体外实验。除了研究II中使用的麦尔维因溶液和储存时间外，测试均按照ISO 4049（1988）进行。使用高效液相色谱法对洗脱单体进行分析。在三点弯曲设备中测试弯曲性能。计算割线模量和断裂挠度以描述测试材料的粘弹性行为。为了研究对牙医皮肤的不良影响，向3500名随机选择的瑞典牙医发送了一份问卷。回复率为88%，对数据进行了统计分析，并与两项关于瑞典普通人群皮肤症状的研究结果进行了比较。邀请过去12个月内患有手部湿疹的瑞典三个主要城市的牙医参加临床检查，其中包括斑贴试验。
在测试期间发现吸附和溶解性范围广泛，含疏水基质单体的材料吸附值较低。储存7天后发现洗脱单体的最大浓度，三乙二醇二甲基丙烯酸酯（TEGDMA）是主要释放的单体。pH值影响了所测试的三种材料中的两种的吸附和溶解性行为。复合树脂材料在水储存后弯曲强度和模量降低，割线模量和断裂挠度可以描述粘弹性行为。与使用相同问题调查的两个年龄匹配的普通人群样本相比，牙医中干性皮肤和手部湿疹的患病率较高。发现成人手部湿疹最重要的预测因素是儿童期湿疹。在临床检查中，刺激性接触性皮炎是主要诊断。7%的人报告在使用基于丙烯酸树脂的材料时出现皮肤症状，但由丙烯酸酯引起的手部湿疹的实际患病率低于1%。然而，50%的牙医被诊断为接触性过敏，主要是由于其他过敏原，如镍、香料或橡胶化学品。
基质组成对所测试的复合树脂材料的吸附和溶解性行为很重要，储存7天后单体释放量最大。pH值影响水吸附和溶解性行为。割线模量和断裂挠度的计算使得能够观察到水对复合树脂材料的增塑作用。牙医中手部湿疹的患病率较高，刺激性接触性皮炎是主要诊断。儿童期湿疹是成人手部湿疹最重要的预测因素。由丙烯酸酯引起的手部湿疹的患病率低于1%。
