Filling Material Bond Strength to Dentin Is Positively Influenced by the Agitation of Endodontic Final Irrigating Solutions

Thefinalstepofirrigationhasbeenconsideredtoofincreasethebondingstrengthoffillingmaterial to dentin. This study investigated the impact of three final -step irrigation methods on the endodonticsealer bond strength to dentin by using a micro push-out test.

Palatal roots of humanmaxillary molars were cleaned and shaped and randomly divided in six groups (n=15) according to the final-step irrigation method and the type of root canal sealer used. The solutions used for the final -step irrigationwere 17% ethylenediaminetetraacetic acid and 2.5% sodium hypochlorite, which underwent thre e

1)syringe-needle irrigation/conventional, 2) passive ultrasonic irrigation, and 3) XP-e ndo Finisher agitation. Theroot canal sealers used were: EndoSequence BC Sealer, and AH-Plus sealer. Roots were obturated with thesingle cone technique and then, cross -sectioned in 2- mm-thick slices (3 slices from each root). Push -out testwas performed on the sliced specimens (cervical, middle, and apical thirds) with a universal testing machine.Bond strength values were recorded in megapascal (MPa). Subsequently, each specimen was longitudinallysplit to verify the type of failur e. Data analysis was performed using Johnson transformation, three -way analysisof variance, Tukey’s post -hoc tests, and the partial Eta squared test.

There were significant differencesin bond strength between the sealers [AH: 4.46±2.24 and BC: 3.47±2.19 MPa (P<0.001)]; between final -stepirrigation methods [ passive ultrasonic irrigation: 4.52±2.25, XP-e ndo Finisher: 3.93±3.93 and syringe-needleirrigation/conventional: 3.37±2.51 MPa (P<0.001)], and between the root canal thirds represented by the slicedspecimens [cervical: 5.45±2.39, middle: 4.14±1.99 and apical: 2.30±1.30 MPa (P<0.001)]. The interactionbetween the variables had no significance (P>0.05).

Agitation of the final irrigating solution mayimprove the bonding of the sealer to canal walls. AH-Plus sealer had the highest bond strength. The bondstrength reduced significantly towards the apical thir