The effect of three ways of fiber post removal on vertical root fracture resistance (An in vitro study)

Abstract

Aim of the study : this study aimed to evaluate vertical root fracture resistance after fiber post removal using three different techniques   ( ultrasonic tips , peeso reamers , D.T post removal kit)

Materilas and methods : the study was conducted on 45 human tooth ( single canaled lower premolars ) which were divided into 3 groups according to the way of removal , the samples lengh were made equal, similar mesiodistal and buccolingual root dimensions were included (+- 8%) . the root canal was obturated using lateral condensation technique and resin reinforced glass fibers were applied using dual cured resin cement after preparing the fiber post grave for 11 mm starting from the reference point. After that the posts were removed using  D.T post removal kit in the first group and using ultrasonic tips (E5d) in the second group and peeso reamers in the third group. After the removal all spaces were filled with warm gutta-percha using obtura device (woodpecker china) and all samples were tested by hydrolic mechanical test machine by applying forces parallel to the long axes of the teeth until the failure happens, The results were studied and analyzed using spss.

Results : the ultrasonic tips group showed more resistance to vertical root fracture and the difference were statistically significant(P≤ 0.05) whereas the other groups showed no significant difference.

Conclusion : we recommend to use ultrasonic tips to remove resin

reinforced fiber glass posts because they reduce the incidence of vertical root fracture compared to rotating reamers.