Santin Gabriela Cristina, Queiroz Alexandra Mussolino de, Palma-Dibb Regina Guenka, Oliveira Harley Francisco de, Nelson Filho Paulo, Romano Fábio Lourenço
Department of Dentistry , UEM- Universidade Estadual de Maringá , Maringá, PR, Brazil.
Department of Dentistry, UNINGÁ - Centro Universitário Ingá, Maringá, PR, Brazil.
Braz Dent J. 2018 Mar-Apr;29(2):128-132. doi: 10.1590/0103-6440201801436.
Patients undergoing radiotherapy treatment present more susceptibility to dental caries and the use of an orthodontic device increases this risk factor due to biofilm accumulation around the brackets. The objective of this study was to evaluate the shear bond strength to irradiated permanent teeth of orthodontic brackets bonded with conventional glass ionomer cement and resin-modified glass ionomer cement due to the fluoride release capacity of these materials. Ninety prepared human premolars were divided into 6 groups (n=15), according to the bonding material and use or not of radiation: CR: Transbond XT composite resin; RMGIC: Fuji Ortho LC conventional glass ionomer cement; GIC: Ketac Cem Easymix resin-modified glass ionomer cement. The groups were irradiated (I) or non-irradiated (NI) prior to bracket bonding. The specimens were subjected to a fractioned radiation dose of 2 Gy over 5 consecutive days for 6 weeks. After the radiotherapy, the brackets were bonded on the specimens with Transbond XT, Fuji Ortho LC and Ketac Cem Easymix. After 24 h, the specimens were subjected to shear bond strength test. The image of enamel surface (classified by Adhesive Remnant Index - ARI) was also evaluated and its frequency was checked among groups/subgroups. The shear bond strength variable was evaluated with ANOVA and Tukey's post-hoc test. GIC group showed the lowest adhesion values among the groups (p<0.05). There was no statistically significant difference among non-irradiated and irradiated groups (p>0.05). As for the ARI, the CR-I group showed the highest material retention on enamel surface among the irradiated groups. RMGIC group showed the highest values for shear bond strength and presented ARI acceptable for clinical practices.
接受放射治疗的患者更容易患龋齿，而使用正畸装置会因托槽周围生物膜的积聚增加这种风险因素。本研究的目的是评估由于这些材料的氟释放能力，用传统玻璃离子水门汀和树脂改性玻璃离子水门汀粘结的正畸托槽与照射后的恒牙之间的剪切粘结强度。根据粘结材料以及是否进行放射治疗，将90颗制备好的人类前磨牙分为6组（n = 15）：CR组：Transbond XT复合树脂；RMGIC组：Fuji Ortho LC传统玻璃离子水门汀；GIC组：Ketac Cem Easymix树脂改性玻璃离子水门汀。在粘结托槽之前，对这些组进行照射（I）或未照射（NI）。对标本连续5天每天给予2 Gy的分次辐射剂量，持续6周。放射治疗后，用Transbond XT、Fuji Ortho LC和Ketac Cem Easymix将托槽粘结在标本上。24小时后，对标本进行剪切粘结强度测试。还评估了釉质表面的图像（根据粘结剂残留指数 - ARI分类），并检查了各组/亚组之间的频率。用方差分析和Tukey事后检验评估剪切粘结强度变量。GIC组在各组中显示出最低的粘结值（p<0.05）。未照射组和照射组之间没有统计学上的显著差异（p>0.05）。至于ARI，CR-I组在照射组中显示出在釉质表面的材料保留率最高。RMGIC组显示出最高的剪切粘结强度值，并且呈现出临床实践可接受的ARI。
