Paryab Mehrsa, Sharifi Shahrzad, Kharazifard Mohammad Javad, Kumarci Nazanin
Department of Paediatric Dentistry, International Campus, Tehran University of Medical Sciences, Tehran, Iran.
School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
J Lasers Med Sci. 2019 Summer;10(3):235-240. doi: 10.15171/jlms.2019.38. Epub 2018 Jul 6.
One of the main applications of laser in dentistry is the removal of dental caries and preparation of restorative cavities. The morphology and wettability of laser prepared surfaces are different from that of those prepared with conventional method which may affect the quality of the adhesive potential of bonding agents in these surfaces. This study aimed to assess the shear bond strength of a total-etch and self-etch adhesive system to primary tooth dentin prepared by two different energy densities of Er:YAG laser in comparison with surfaces prepared by bur. A total of 60 human primary second molars extracted for orthodontic purposes were selected and randomly divided into 3 main groups of equal (n=20). Group A: Preparation of dentin surface by bur; group B: Preparation of dentin surface by laser with 300 mJ energy level; group C: Preparation of dentin surface by laser with 400 mJ energy level. In each of the main groups, the teeth were randomly assigned to 2 subgroups. Composite resin material was bonded with the total-etch adhesive system in subgroups A1, B1, and C1 and with the self-etch adhesive system in subgroups A2, B2, and C2. The samples were thermo-cycled, and composite restorations shear bond strength was measured in MPa. Data were analyzed using two-way analysis of variance (ANOVA), and values less than 0.05 were considered statistically significant. The highest and the lowest shear bond strength values were observed in group A2 (Preparation by bur- Composite resin material bonded by Clearfil SE Bond) and group C2 (Preparation by laser with 400 mJ energy level - Composite resin material bonded by Clearfil SE Bond), respectively. The results showed no statistically significant differences between the study subgroups ( > 0.05). It is concluded that in terms of shear bond strength to dentin, Single Bond and Clearfil SE Bond adhesive agents adequately perform in primary tooth dentin prepared by Er: YAG laser with energy levels of 300 and 400 mJ and frequency of 10 Hz.
激光在牙科领域的主要应用之一是龋齿的去除和修复性窝洞的制备。激光制备表面的形态和润湿性与传统方法制备的表面不同，这可能会影响这些表面上粘结剂的粘结潜力质量。本研究旨在评估全酸蚀和自酸蚀粘结系统与经两种不同能量密度的铒：钇铝石榴石（Er:YAG）激光制备的乳牙牙本质之间的剪切粘结强度，并与用牙钻制备的表面进行比较。总共选择了60颗因正畸目的而拔除的人类乳牙第二磨牙，并随机分为3个主要组，每组20颗。A组：用牙钻制备牙本质表面；B组：用能量水平为300 mJ的激光制备牙本质表面；C组：用能量水平为400 mJ的激光制备牙本质表面。在每个主要组中，牙齿被随机分配到2个亚组。在A1、B1和C1亚组中，复合树脂材料用全酸蚀粘结系统粘结，在A2、B2和C2亚组中，复合树脂材料用自酸蚀粘结系统粘结。对样品进行热循环处理，并以兆帕（MPa）为单位测量复合修复体的剪切粘结强度。使用双向方差分析（ANOVA）对数据进行分析，小于0.05的值被认为具有统计学意义。最高和最低的剪切粘结强度值分别出现在A2组（用牙钻制备 - 用Clearfil SE Bond粘结复合树脂材料）和C2组（用能量水平为400 mJ的激光制备 - 用Clearfil SE Bond粘结复合树脂材料）。结果显示各研究亚组之间无统计学显著差异（P>0.05）。得出的结论是，就与牙本质的剪切粘结强度而言，Single Bond和Clearfil SE Bond粘结剂在能量水平为300和400 mJ、频率为10 Hz的Er:YAG激光制备的乳牙牙本质中表现良好。
