Properties of a novel polysiloxane-guttaperchacalcium silicate-bioglass-containing root canal sealer

tObjective. Root canal filling sealers based on polymethyl hydrogensiloxane or poly-methyl hydrogensiloxane-guttapercha – introduced to improve the quality of conventionalguttapercha-based and resin-based systems – showed advantages in handiness and clinicalapplication.The aim of the study was to evaluate the chemical–physical properties of a novelpolysiloxane-guttapercha calcium silicate-containing root canal sealer (GuttaFlow bioseal).Methods. GuttaFlow bioseal was examined and compared with GuttaFlow2, RoekoSeal andMTA Fillapex sealers. Setting times, open and impervious porosity and apparent porosity,water sorption, weight loss, calcium release, and alkalinizing activity were evaluated. ESEM-EDX-Raman analyses of fresh materials and after soaking in simulated body fluid were alsoperformed.Results. Marked differences were obtained among the materials.GuttaFlow bioseal showed low solubility and porosity, high water sorption, moderatecalcium release and good alkalinizing activity. MTA Fillapex showed the highest calciumrelease, alkalinizing activity and solubility, RoekoSeal the lowest calcium release, no alkalin-izing activity, very low solubility and water sorption. Only GuttaFlow bioseal showed apatiteforming ability.Significance. GuttaFlow bioseal showed alkalinizing activity together with negligible sol-ubility and slight calcium release. Therefore, the notable nucleation of apatite and apatiteprecursors can be related to the co-operation of CaSi particles (Si OH groups) with polysilox-ane (Si O Si groups).The incorporation of a calcium silicate component into polydimethyl polymethylhydro-gensiloxane guttapercha sealers may represent an attractive strategy to obtain a bioactivebiointeractive flowable guttapercha sealer for moist/bleeding apices with bone defects inendodontic therapy.