Cadenaro M, Pashley D H, Marchesi G, Carrilho M, Antoniolli F, Mazzoni A, Tay F R, Di Lenarda R, Breschi L
Department of Biomedicine, University of Trieste, Trieste, Italy.
Dent Mater. 2009 Oct;25(10):1269-74. doi: 10.1016/j.dental.2009.05.008. Epub 2009 Jun 30.
This study examined the effect of chlorhexidine (CHX) content on degree of conversion (DC) and E-modulus of experimental adhesive blends. The hypothesis tested was that increasing concentrations of CHX result in decreased DC and E-modulus in relation to adhesive hydrophilicity.
Experimental adhesive blends with increasing hydrophilicity R2 (70% bisGMA, 28.75% TEGDMA); R3 (70% BisGMA, 28.75% HEMA); R4 (40% BisGMA, 30% TCDM, 28.75% TEGDMA); R5 (40% BisGMA, 30% BisMP, 28.75% HEMA) and different CHX concentrations (1 and 5%) were analyzed. 5% CHX could not be dissolved in R2. A differential scanning calorimeter was used to measure the DC of resin blends. Photopolymerized disks of the experimental comonomer mixtures (n=10/gp) were used to measure the E-modulus of each specimen using a biaxial flexure test. Data were analyzed with two-way ANOVA (resin type and CHX concentration) and Tukey's post hoc test.
The addition of 1% CHX did not significantly alter the DC of R2 and R3. Significant decrease in R3 DC values was observed when 5% CHX was added. CHX significantly increased the DC of R4 and R5. 1% CHX reduced the E-modulus of all resins (p<0.05) except for R2, in which the E-modulus was significantly increased (p<0.05). 5% CHX significantly reduced the E-modulus of resins R3 to R5 (p<0.05).
In conclusion, increasing concentrations of CHX dissolved in resin blends had little adverse effect on DC but decreased the E-modulus 27-48% compared to controls. Solvation of CHX in ethanol prior to incorporation of CHX into R2 may permit higher CHX concentrations without lower polymer stiffness.
本研究考察了洗必泰（CHX）含量对实验性胶粘剂混合物的转化率（DC）和弹性模量的影响。所检验的假设是，CHX浓度增加会导致与胶粘剂亲水性相关的DC和弹性模量降低。
分析了亲水性递增的实验性胶粘剂混合物R2（70%双甲基丙烯酸缩水甘油酯，28.75%三乙二醇二甲基丙烯酸酯）；R3（70%双甲基丙烯酸缩水甘油酯，28.75%甲基丙烯酸羟乙酯）；R4（40%双甲基丙烯酸缩水甘油酯，30%三羟甲基丙烷三甲基丙烯酸酯，28.75%三乙二醇二甲基丙烯酸酯）；R5（40%双甲基丙烯酸缩水甘油酯，30%双甲基丙烯酸甲酯，28.75%甲基丙烯酸羟乙酯）以及不同CHX浓度（1%和5%）。5%的CHX无法溶解于R2中。使用差示扫描量热仪测量树脂混合物的DC。使用双轴弯曲试验，对实验性共聚单体混合物的光聚合圆盘（每组10个）进行测量，以得到每个样本的弹性模量。数据采用双向方差分析（树脂类型和CHX浓度）以及Tukey事后检验进行分析。
添加1%的CHX对R2和R3的DC没有显著影响。当添加5%的CHX时，观察到R3的DC值显著降低。CHX显著提高了R4和R5的DC。1%的CHX降低了除R2以外所有树脂的弹性模量（p<0.0），其中R2的弹性模量显著增加（p<0.05）。5%的CHX显著降低了树脂R3至R5的弹性模量（p<0.05）。
总之，树脂混合物中溶解的CHX浓度增加对DC几乎没有不利影响，但与对照组相比，弹性模量降低了27%-48%。在将CHX掺入R2之前，先将CHX溶解于乙醇中，可能允许更高的CHX浓度而不会降低聚合物硬度。
