Effect of three post systems on the fracture resistance of teeth with extensive coronal structure loss and internal...

The purpose of this study was to evaluate the effect of three different post systems on the fracture resistance of maxillary incisors with simulated internal root resorption and extensive coronal structure loss.

A total of 100 freshly extracted maxillary incisors were randomly divided into five groups (n = 20): glass fiber post, polyetheretherketone (PEEK) post, Ribbond post, positive control, and negative control. Internal resorption cavities were prepared 6 mm above the apex in each tooth, and the canals were filled using the single-cone technique with Sure-Seal Root bioceramic sealer. PEEK posts were digitally designed based on the dimensions of the glass fiber posts and fabricated in a dental laboratory. All posts were cemented using Panavia V5 resin cement according to the manufacturer's instructions. The specimens were tested under static loading at a 45° angle using a universal testing machine until fracture occurred. Data were analyzed using one-way ANOVA and Tamhane's post hoc test (P < .05).

The highest mean fracture resistance was observed in the negative control group (1559.4 ± 209.1 N), while the lowest was in the positive control group (492.9 ± 73.4 N). Among the post-applied groups, the PEEK post group exhibited a significantly higher fracture resistance (907.4 ± 104 N) compared to the others (P < .001).

Although all post systems increased the fracture resistance, none reached the strength of intact teeth. PEEK posts yielded the highest fracture resistance under the present experimental conditions.