Fracture resistance of maxillary anterior teeth with flared root canals restored with fiber posts by 3 me-thods / 实用口腔医学杂志

ABSTRACT

Objective:To investigate the influence of 3 methods of fiber posts on fracture resistance of maxillary anterior teeth with flared root canals.Methods:32 human maxillary central incisors were assigned randomly to 4 groups(n =8).The crowns of the teeth were removed at a level 2 mm incisal to the cementoenamel junction(CEJ).After root canal therapy,flared canals were simula-ted in 3 groups.The flared canals were reinforced with resin cement(group A),resin composite(group B)and accessory posts (group C)respectively.In group D flared canals were not created.The same size fiber posts were cemented with resin cement in all groups.After posts cementation and composite resin core formation,all teeth were restored with metal crowns.Then the roots of the teeth were embedded in acrylic resin blocks up to 2 mm below the CEJ.The samples were loaded in a testing machine until failure occurred.Results:The maximum load value(N)for fracture of group A,B,C and D was 295.94 ±69.11,450.51 ±54.68, 479.37 ±77.81 and 618.51 ±87.42 respectively(F =118.127,P =0.000);group B vs C,P >0.05,between each 2 of the other groups,P 0.05). Conclusion:Reinforcement of flared canal with resin composite and accessory posts can increase the fracture restance of the tooth root and the most of fracture patterns are beneficial for the second repair.