Fennis W M M, Kreulen C M, Wolke J G C, Fokkinga W A, Machado C, Creugers N H J
Department of Oral Function and Prosthetic Dentistry, Radboud University Nijmegen Medical Centre, The Netherlands.
J Dent. 2009 Jun;37(6):462-7. doi: 10.1016/j.jdent.2009.03.003. Epub 2009 Mar 31.
Fractured coronal fragments of incisors can be adhered to the remaining tooth with resin composite, but are prone to failure. This study explores whether mini fibre-reinforced composite (FRC) anchors increase fracture resistance of reattached fragments.
Forty-five extracted incisors were randomly divided into three groups. In Groups A and B coronal fragments were reattached to the remaining tooth, with additionally two anchors placed in Group B. In Group C resin composite buildups were made. Specimens were statically loaded until failure occurred. Failure modes were characterized as intact remaining tooth substrate (adhesive or cohesive failure of coronal fragment) or fractured remaining tooth substrate (fracture limited to enamel or extending into dentin).
Mean fracture loads were 255N (SD=108N) for Group A, 599N (SD=465N) for Group B and 786N (SD=197N) for Group C (values significantly different, all p values <0.05). Group A showed purely adhesive failures, while Groups B and C showed 73 and 53% fractures of remaining tooth substrate (p<0.05).
Mini FRC anchors increase fracture resistance of reattached coronal fragments, but induce more remaining tooth substrate fractures.
门牙的冠状骨折碎片可用树脂复合材料粘结到剩余牙齿上，但容易失败。本研究探讨微型纤维增强复合材料（FRC）锚钉是否能提高重新附着碎片的抗折性。
45颗拔除的门牙随机分为三组。A组和B组将冠状骨折碎片重新附着到剩余牙齿上，B组额外放置两个锚钉。C组制作树脂复合材料堆塑体。对标本进行静态加载直至发生破坏。破坏模式分为剩余牙齿基底完整（冠状骨折碎片的粘结或内聚破坏）或剩余牙齿基底骨折（骨折仅限于牙釉质或延伸至牙本质）。
A组平均抗折载荷为255N（标准差=108N），B组为599N（标准差=465N），C组为786N（标准差=197N）（数值差异显著，所有p值<0.05）。A组表现为单纯的粘结破坏，而B组和C组分别有73%和53%的剩余牙齿基底骨折（p<0.05）。
微型FRC锚钉可提高重新附着的冠状骨折碎片的抗折性，但会导致更多的剩余牙齿基底骨折。
