The aim of this paper is to perform optimization of photopolymerization process of dental composites in order to obtain maximum hardness. Samples (5 mm diameter; 2, 3 and 4 mm thickness) were made of Universal Composite (UC), Bulk fill Composite (BC) and Flowable Composite (FC). Light curing of specimens was performed with 600, 1000 and 1500 mW/cm² light intensity and an irradiation time of 20, 40 and 60 s. Vickers microhardness on the top and bottom surfaces of samples was measured. Optimization was carried out via regression analysis using QStatLab software. Photopolymerization process parameters were calculated using a specially designed MatLab software-based algorithm. For all composites, regression models for hardness on top and bottom surfaces of composite layer were established. Layer thickness as well as hardness on top and bottom surfaces of each composite was calculated for 21 curing modes varying with light intensity and irradiation time. It was established that photopolymerization guidelines only of FC manufacturer guarantee the required hardness, while recommended regimes for UC and BC did not satisfy this requirement. Tables, containing recommended light curing regimes, were developed for three composite types, guaranteeing high hardness of composite restoration. They were designed to facilitate work of dentists in dental offices.

中文翻译：

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牙科复合材料光聚合工艺的优化

本文的目的是对牙科复合材料的光聚合过程进行优化，以获得最大的硬度。样品（直径5毫米；厚度2、3和4毫米）由通用复合材料（UC），大容量填充复合材料（BC）和可流动复合材料（FC）制成。以600、1000和1500 mW / cm ²进行样品的光固化光强度和20、40和60 s的照射时间。测量样品的顶部和底部表面的维氏显微硬度。使用QStatLab软件通过回归分析进行优化。使用专门设计的基于MatLab软件的算法来计算光聚合过程的参数。对于所有复合材料，建立了复合材料层顶部和底部表面硬度的回归模型。针对随光强度和照射时间而变化的21种固化模式，计算了每种复合材料的层厚度以及顶部和底部表面的硬度。可以确定的是，仅FC制造商的光聚合指南可以保证所需的硬度，而UC和BC的推荐方案不能满足该要求。包含建议的光固化方案的表格，针对三种复合材料类型而开发，可确保复合材料修复体的高硬度。它们旨在促进牙医在牙科诊所的工作。