Toledano Manuel, Osorio Raquel, Osorio Estrella, Aguilera Fátima S, Yamauti Monica, Pashley David H, Tay Franklin
Department of Dental Materials, School of Dentistry, University of Granada, Granada, Spain.
J Mater Sci Mater Med. 2007 Dec;18(12):2355-61. doi: 10.1007/s10856-007-3161-z. Epub 2007 Jun 14.
The objective of this study is to evaluate the effect of a bacterial collagenase on the degradation of resin-dentin bonds. Human dentin surfaces were bonded with: an etch-&-rinse self-priming adhesive (SB), a two-step self-etching primer/adhesive (SEB), and a 1-step self-etching adhesive (OUB). Composite build-ups were constructed. The bonded teeth were stored (24 h, 3 months, 1 year) in distilled water or in a buffered bacterial collagenase solution. Half of the specimens were stored as intact bonded teeth (Indirect Exposure/IE). The other half were sectioned into beams prior to storage (Direct Exposure/DE). After storage the intact teeth were sectioned into beams and all specimens were tested for microtensile bond strengths (MTBS). ANOVA and multiple comparisons tests were performed. Fractographic analysis was performed by scanning electron microscopy. The inclusion of bacterial collagenase in the storing solution did not lower the MTBS values over those seen in specimens stored in water. SB and SEB bonds strength were equal, and were superior to OUB. After 3 months of DE, SB and OUB bonded specimens showed decreases in MTBS; similar reductions required 1 year for SEB/DE. MTBS did not decrease in IE specimens except for OUB. Resin and collagen dissolution were evident in DE groups after storing.
本研究的目的是评估一种细菌胶原酶对树脂-牙本质粘结降解的影响。用人牙本质表面粘结以下材料：一种酸蚀冲洗自粘结底漆（SB）、一种两步自酸蚀底漆/粘结剂（SEB）和一种一步自酸蚀粘结剂（OUB）。构建复合树脂堆积体。将粘结的牙齿在蒸馏水中或缓冲细菌胶原酶溶液中储存（24小时、3个月、1年）。一半标本作为完整的粘结牙齿储存（间接暴露/IE）。另一半在储存前切成梁状（直接暴露/DE）。储存后，将完整牙齿切成梁状，所有标本进行微拉伸粘结强度（MTBS）测试。进行方差分析和多重比较测试。通过扫描电子显微镜进行断口分析。与储存在水中的标本相比，储存溶液中加入细菌胶原酶并未降低MTBS值。SB和SEB的粘结强度相等，且优于OUB。DE 3个月后，SB和OUB粘结的标本MTBS降低；SEB/DE需要1年才出现类似程度的降低。除OUB外，IE标本的MTBS未降低。储存后，DE组出现明显的树脂和胶原溶解。
