Dataset - Effect of Glycerin Application on the Surface Hardness of Composite Resins

This dataset was developed to test the hypothesis that the application of glycerin prior to light-curing improves the surface hardness of composite resins by minimizing the oxygen-inhibited layer and enhancing the polymerization process. The dataset includes both in vitro and clinical studies that compared surface hardness values of composite resins with and without prior glycerin application. The data comprises key variables extracted from eligible studies, including author and year of publication, country of origin, study design (in vitro or clinical), type of composite resin, glycerin application details (concentration, timing, and method), light-curing protocol, surface hardness testing method (e.g., Vickers or Knoop), pre-test storage or clinical conditions, and quantitative results for surface hardness (mean and standard deviation). Risk of bias was assessed using appropriate tools based on the study type (RoBDEMAT for in vitro and ROBINS-I for non-randomized clinical studies). The findings reveal a consistent trend across most included studies, showing higher surface hardness values in the glycerin-treated groups. This supports the hypothesis that glycerin application can improve polymerization outcomes. However, variability in testing protocols, resin types, and glycerin formulations suggests the need for further standardization. The data were systematically extracted by calibrated reviewers using a standardized Excel spreadsheet and subsequently exported to RStudio (latest version) for quantitative analysis. All procedures followed PRISMA guidelines. This dataset can be reused for meta-analyses, subgroup analyses by resin type or test conditions, and methodological comparisons across studies. Clear variable labels and consistent formatting enable straightforward interpretation and integration into related research. All included data are available in English and were obtained from full-text articles retrieved from indexed scientific databases. No synthetic or simulated data were used.本数据集旨在验证下述假说：光固化前涂抹甘油可通过抑制氧阻聚层形成、强化聚合反应过程，提升复合树脂的表面硬度。本数据集涵盖体外实验与临床研究两类，均对比了预先涂抹甘油与未预先涂抹甘油的复合树脂表面硬度值。 本数据集包含从符合纳入标准的研究中提取的核心变量，具体包括：作者与发表年份、研究起源国家、研究设计类型（体外实验或临床研究）、复合树脂类型、甘油涂抹细节（浓度、时机与操作方式）、光固化方案、表面硬度测试方法（如维氏硬度计或努氏硬度计）、测试前储存条件或临床环境，以及表面硬度的定量结果（均值与标准差）。研究偏倚风险依据研究类型采用适配工具进行评估：体外实验研究使用RoBDEMAT工具，非随机临床研究使用ROBINS-I工具。 纳入的多数研究均呈现一致趋势：涂抹甘油的实验组表面硬度数值更高，这验证了甘油涂抹可改善聚合反应效果的假说。但由于测试方案、树脂类型与甘油配方存在差异，仍需进一步开展标准化研究。 本数据集由经过校准的评审人员采用标准化Excel电子表格系统提取，随后导出至最新版RStudio中开展定量分析。所有操作流程均遵循PRISMA声明规范。本数据集可用于meta分析、按树脂类型或测试条件开展的亚组分析，以及不同研究间的方法学对比。清晰的变量标签与统一的格式便于研究人员直接解读并将其整合至相关研究工作中。 本数据集纳入的所有数据均为英文来源，取自从索引化科学数据库中检索获得的全文文献，未使用任何合成或模拟数据。