The Effect of Obturation Technique on the Push-out Bond Strength of Calcium Silicate Sealers

• Push-out bond strengths of 2 calcium silicate–based sealers (EndoSequence BC sealer and MTA Plus) were tested when they were used in a single-cone technique and the continuous wave technique.
• The MTA Plus continuous wave group had significantly lower bond strengths than the other groups.
• Bond strengths were higher when the sealers were used in a single-cone technique compared with the continuous wave technique.
• Modes of failures were primarily cohesive or mixed.
• It is not recommended to use EndoSequence BC sealer and MTA Plus in a thermoplastic technique.

IntroductionCalcium silicate–based sealers are known to have excellent sealing ability and bioactivities. They are typically recommended to be used in a single-cone (SC) technique. No studies have evaluated the effects of the thermoplastic obturation technique on the dentin interface of these sealers. The purpose of this study was to evaluate the push-out bond strengths of MTA Plus Sealer (Avalon Biomed Inc, Bradenton, FL) and EndoSequence BC Sealer (BC; Brasseler USA, Savannah, GA) when they were used in a thermoplastic technique.MethodsFifty single-rooted human extracted teeth were randomly divided into 5 groups (n = 10), instrumented, and obturated with the SC technique or continuous wave (CW) technique: group 1, BC-SC; group 2, BC-CW; group 3, MTA Plus–SC; group 4, MTA Plus–CW; and group 5, AH Plus (Dentsply DeTrey, Konstanz, Germany)–CW. The roots were sectioned into 1.0-mm-thick slices, and bond strengths were measured using a standardized push-out test. The mode of failure was determined by visual inspection under magnification.ResultsThe MTA Plus–CW had statistically significant lower bond strengths than all other groups. The BC-SC group had statistically higher bond strengths than the MTA Plus–SC and AH Plus–CW groups. No significant differences were seen among the other groups. Modes of failure were predominately cohesive or mixed except for group 4 (ie, MTA Plus–CW) in which nearly half the specimens had no visible sealer.ConclusionsBC and MTA Plus sealer showed favorable bond strengths when used in an SC technique. The CW obturation technique decreased the bond strengths of these sealers.