Thaís Diniz Segatto, DDS, MSc, graduate student, Department of Occlusion, Fixed Prosthodontics and Dental Materials, School of Dentistry, Federal University of Uberlândia, MG, Brazil.
Karen Katlein Dolenkei, DDS, MSc, graduate student, Department of Occlusion, Fixed Prosthodontics and Dental Materials, School of Dentistry, Federal University of Uberlândia, MG, Brazil.
Oper Dent. 2024 Sep 1;49(5):540-550. doi: 10.2341/23-125-L.
This study aimed to assess the impact of battery levels in single-peak and multi-peak light-curing units (LCUs) on irradiance, and their effects on glass fiber post push-out bond strength to root dentin and the degree of conversion of dual-cure universal resin cement.
Sixty bovine roots underwent endodontic treatment and were randomly distributed into 6 groups (n=10), formed by combining two LCUs (single-peak and multipeak) and three battery levels (100%, 50%, and 10%). A spectrophotometer measured irradiance (mW/ cm2) and spectral irradiance (mW/cm2/nm). Push-out bond strength (PBS) tests occurred at three root regions (cervical, middle, and apical), with optical and scanning electron microscopy for failure mode analysis. Degree of conversion (DC) was evaluated across the root regions. Data were analyzed using two-way repeated measures ANOVA and the Tukey HSD test. The Fisher exact test verified failure modes (α=0.05).
As multipeak LCU battery levels decreased, emitted irradiance also diminished, with notable PBS reductions in the apical thirds. Failure modes were influenced by different conditions, primarily exhibiting mixed modes. Battery levels significantly impacted DC in the multipeak LCU, particularly in the cervical region, while the single-peak LCU exhibited DC reduction at the 10% battery level in the cervical region.
Emitted irradiance, resin cement DC, and glass fiber post bond strength to root dentin may be influenced by varying cordless LCUs and battery levels.
本研究旨在评估单峰和多峰光固化器（LCU）中电池电量对辐照度的影响，及其对玻璃纤维桩推出力与根管牙本质粘结强度和双固化通用树脂水门汀转化率的影响。
60 个牛牙根管接受根管治疗，并随机分为 6 组（n=10），组合方式为两种 LCU（单峰和多峰）和三种电池电量（100%、50%和 10%）。分光光度计测量辐照度（mW/cm2）和光谱辐照度（mW/cm2/nm）。在三个根管区域（颈段、中段和根尖段）进行推出力粘结强度（PBS）测试，并用光学显微镜和扫描电子显微镜进行失效模式分析。评估根区的转化率（DC）。使用双向重复测量方差分析和 Tukey HSD 检验进行数据分析。Fisher 确切检验验证失效模式（α=0.05）。
随着多峰 LCU 电池电量的降低，发射的辐照度也降低，根尖段的 PBS 明显降低。失效模式受到不同条件的影响，主要表现为混合模式。电池电量对多峰 LCU 的 DC 有显著影响，特别是在颈段，而单峰 LCU 在颈段电池电量为 10%时，DC 降低。
不同的无绳 LCU 和电池电量可能会影响发射的辐照度、树脂水门汀 DC 和玻璃纤维桩与根管牙本质的粘结强度。
