Effect of posts on the fracture resistance of load cycled endodontically treated premolars restored with direct composite resin

Aim

The aim of this study was to investigate the fracture resistance and failure mode of premolars restored with composite resin using various prefabricated posts.

Methods

Sixty sound maxillary premolars were divided into four equal sized groups. All but the control group reveived endodontic treatment followed by placement of MOD composite restorations (Tetric Ceram; Ivoclar, Leichtenstein) as follows: Group T = no post, Group DT= fiber reinforced composite post (DT Light-Post, RTD, St Egreve, France), Group FL= prefabricated metal post (Filpost). The control group (C) had no cavity preparation. After thermal and load cycling, static load was applied at 30 degrees’ angle until fracture. Failure modes were categorized as restorable and non-restorable. Data were analyzed using the analysis of variance (ANOVA) and Duncan tests (α = 0.06).

Results

The mean value s of fracture loads (N) for all groups were: C (880 +/-258); T (691+/- 239); DT (865+/-269); and FL(388+/-167). Statistically significant differences (P<0.05) were observed for all groups except between groups C and DT. The Chi square test showed failure modesin Groups C and DT were mostly restorable. The most non-restorable fractures were observed in Group FT.

Clinical significance

The results of this study suggest that a quartz fiber post used in conjunction with an MOD composite resin restoration inproves fracture resistance in an endodontically treated pre-molar.