Dental School, University of Santo Amaro, Rua Professor Eneas de Siqueira Neto, 340, CEP: 04829-900, São Paulo, Brazil.
College of Dentistry, University of Saskatchewan, Dental Clinic Building, 105, Wiggins Road, Saskatoon, SK, S7N 5E4, Canada.
J Mech Behav Biomed Mater. 2024 Feb;150:106323. doi: 10.1016/j.jmbbm.2023.106323. Epub 2023 Dec 18.
to investigate the effect of different concentrations of chitosan added to experimental resins containing either BAPO or camphorquinone (CQ) as photoinitiators, regarding degree of conversion (DC), flexural strength (FS), flexural elastic modulus (E), Knoop microhardness (KHN), cytotoxicity, genotoxicity and antimicrobial activity.
Experimental resins with polymeric matrix of BisGMA and TEGDMA was added either 0.5 wt% BAPO or 0.5 wt% camphorquinone/0.2% amine along with and chitosan concentrations of 0.5%; 1.0% or 2.0%. Degree of conversion was measured using Fourier transformed infrared spectroscopy. Flexural strength and elastic modulus were obtained through three-point bending test and Knoop microhardness was measured in a microidenter. Direct cytotoxicity was performed in human keratinocytes and genotoxicity test was done in murine macrophages cells. Antimicrobial activity was acessed against Staphylococcus aureus and Streptococcus mutans through the inhibition halo. Data were analyzed using two-way ANOVA and Tukey teste (α = 0.05).
The materials containing photoinitiator BAPO showed higher values of DC, FS, E, and KHN compared to resins with CQ. The addition of chitosan did not affect the properties of these materials. However, in resins containing CQ, the addition of chitosan improve these properties compared to control group. For the groups containing BAPO the chitosan reduced cytotoxicity and genotoxicity compared to materials with camphorquinone. The materials with 1.0% and 2.0% chitosan showed increased antibacterial activity in the materials containing BAPO as photoinitiator for both bacteria.
The alternative photoinitiator BAPO and chitosan can improve physical and biological properties of photoactivated resins when compared with the materials with photoinitiator camphorquinone.
研究不同浓度壳聚糖添加到含有苯偶姻（BAPO）或樟脑醌（CQ）作为光引发剂的实验树脂中对转化率（DC）、弯曲强度（FS）、弯曲弹性模量（E）、努氏硬度（KHN）、细胞毒性、遗传毒性和抗菌活性的影响。
实验树脂的聚合基质为 BisGMA 和 TEGDMA，分别添加 0.5wt% BAPO 或 0.5wt% CQ/0.2% 胺，以及 0.5%、1.0%或 2.0%的壳聚糖。使用傅里叶变换红外光谱法测量转化率。通过三点弯曲试验获得弯曲强度和弹性模量，通过微硬度计测量努氏硬度。直接细胞毒性在人角质细胞中进行，遗传毒性试验在鼠巨噬细胞中进行。通过抑制晕圈评估对金黄色葡萄球菌和变形链球菌的抗菌活性。使用双因素方差分析和 Tukey 检验（α=0.05）对数据进行分析。
含光引发剂 BAPO 的材料表现出比含 CQ 树脂更高的 DC、FS、E 和 KHN 值。壳聚糖的添加不影响这些材料的性能。然而，在含 CQ 的树脂中，与对照组相比，壳聚糖的添加改善了这些性能。与含樟脑醌的材料相比，含 BAPO 的组中的壳聚糖降低了细胞毒性和遗传毒性。与含光引发剂 CQ 的材料相比，含 1.0%和 2.0%壳聚糖的材料在含 BAPO 的光引发剂的材料中显示出更强的抗菌活性，对两种细菌均有效。
与含有樟脑醌的光引发剂的材料相比，替代光引发剂 BAPO 和壳聚糖可以改善光固化树脂的物理和生物学性能。
