A comparison of root fracture resistance using two root canal sealers. Effects of calcium phosphate endodontic sealers on the behavior of human periodontal ligament fibroblasts and MG63 osteoblast-like cells. Comparing subcutaneous tissue responses to freshly mixed and set root canal sealers Effect of photo-activated disinfection on bond strength of three different root canal sealers Effect of root canal sealers on bond strength of fibreglass posts cemented with self-adhesive resin cements. The effect of photodynamic therapy and polymer solution containing nano-particles of Ag /ZnO on push-out bond strength of the sealers AH-Plus and MTA Fillapex Effect of eugenol-containing sealer and post diameter on the retention of fiber reinforced composite posts Resistance to fracture of roots filled with different sealers.
AIM The aim of this study was to compare in vitro root fracture resistance following root canal filling with either Ketac-Endo or Roth 's root canal sealer . METHODOLOGY The roots of 40 teeth with single canals were instrumented and placed r and omly into four groups of 10 teeth . The prepared canals were obturated with lateral compaction using gutta-percha and Roth 's 801 sealer , lateral compaction and Ketac-Endo sealer or with a single cone and Ketac-Endo sealer ; the fourth group acted as unfilled controls . The roots were stored for 2 weeks in 100 % humidity prior to being mounted in acrylic resin blocks . A steel tipped rod attached to an Instron testing machine was positioned against the canal opening and a slowly increasing force was applied until root fracture occurred . The results were subjected to statistical analysis using Kruskal-Wallis one-way ANOVA . RESULTS There were no significant differences between the groups in terms of force required to vertically fracture the roots . CONCLUSIONS Under the conditions of this study , the use of Ketac-Endo sealer in conjunction with lateral compaction or single-cone obturation techniques does not increase the fracture resistance of root-filled teeth In regard to biological properties of  endodontic sealers  , there are many characteristics that should be considered . The aim of this study was to examine the biological effects of new calcium phosphate-based root canal sealers , CAPSEAL I and CAPSEAL II ( CPS ) , on human periodontal fibroblast cells by examining the expression levels of inflammatory mediators and to compare the effects of CPS on the viability and osteogenic potential of human osteoblast MG63 cells compared to those of other commercially available calcium phosphate sealers [ Apatite Root Sealer type I ( ARS I ) and Apatite Root Sealer III ( ARS III ) ; Sankin Kogyo , Tokyo , Japan ] and a zinc oxide eugenol-based sealer ( Pulp Canal Sealer EWT [ PCS EWT ] ; Kerr , Detroit , MI ) . The levels of IL-6 in the new CPS group ( CAPSEAL I , II ) were higher than those in the control and all experimental groups at all time points after 2 h. TGF-β1 and FGF-1 levels decreased at 72 h compared to the levels in the control , in cells treated with every sealers except ARS I. The new CPS sealers showed low cytotoxicity . Reverse transcription polymerase chain reaction showed that CAPSEAL I , II , and Apatite Root Sealer type III induced expression of early stage markers of differentiation ( alkaline phosphatase and osteopontin ) at 7 days . Also , new CPS showed higher mineralized nodule formation at 28 days . These results suggest that CAPSEAL I and II facilitate the periapical dentoalveolar and alveolar healing by controlling cellular mediators from PDL cells and osteoblast differentiation of precursor cells INTRODUCTION : The purpose of this study was to compare the subcutaneous tissue responses of freshly mixed or set endodontic root canal sealers ( i.e. RoekoSeal , AH26 , AH Plus ) in Wistar Albino rats . MATERIAL S AND METHODS : Seventy-two male albino rats weighing 200 - 250 g were used . The animals were r and omly divided into six groups of 12 rats each . Root canal sealers were implanted in subcutaneous tissue in both freshly mixed and set conditions . The animals were sacrificed after 7 , 14 , and , 60 days . After histological preparation and Hematoxylin and Eosin ( H&E ) staining , the specimens were evaluated for capsule thickness , severity and extent of inflammation , and necrosis . Results were statistically analyzed using Multivariate ANOVA test . RESULTS : Differences between set and freshly mixed root canal sealers were significant ( P=0.014 ) , but not significant between test material s and controls , except for capsule thickness and extent of inflammation between control and AH26 ( P=0.019 and P=0.006 respectively ) . The interaction between the type of material and setting condition was significant for capsule thickness and severity of inflammation in AH26 specimens at 14 and 60 days ( P=0.001 ) . CONCLUSION : Based on the results of this study assessing the biocompatibility , both set and freshly mixed states can be used . [ Iranian Endodontic Journal 2009;4(4):152 - 7 Introduction : The aim of this in vitro study was to evaluate the bond strength of Photo-Activated Disinfection ( PAD ) system to dentin with different root canal sealers by using a push-out test design . Material s and Methods : A total of 30 extracted m and ibular premolar teeth with single and straight roots were used . The crowns were removed and the root canals were prepared by using ProTaper rotary files . The smear layer was removed and the roots were r and omly divided into two groups ( n = 15 ) according to the use of PAD system as the final disinfecting agent . Each group was then divided into 6 ( n = 5 ) subgroups and obturated with gutta-percha and 3 different root canal sealers . The groups were Group 1 : Sodium hypochlorite ( NaOCl ) + ethylenediaminetetraacetic acid (EDTA)-AH Plus sealer ; Group 2 : NaOCl + EDTA + PAD-AH Plus ; Group 3 : NaOCl + EDTA-Sealapex ; Group 4 : NaOCl + EDTA + PAD-Sealapex ; Group 5 : NaOCl + EDTA-mineral trioxide aggregate (MTA)-Fiallapex ; and Group 6 : NaOCl + EDTA + PAD-MTA-Fillapex . 1-mm thickness horizontal sections ( n : 5 × 4 = 20 ) were sliced for the push-out bond strength measurement . Results : Group 3 and 4 showed significantly lower bond strengths compared with all the other groups ( P < 0.05 ) . No statistically significant difference was found among Groups 1 , 2 and 5 , but there was statistically significant difference between Group 5 and 6 ( P < 0.05 ) . Conclusion : This in vitro study indicated that the PAD system adversely affected the bond strength of the MTA Fillapex root canal sealer AIM This study evaluated the effects of different root canal sealers on the bond strength of a fibreglass post cemented with self-adhesive resin cements . METHODOLOGY The root canals of 50 extracted maxillary single-rooted canine teeth were prepared with the crown-down technique and r and omly divided into five groups according to the sealer used : group 1 : control group , gutta-percha points only ( no sealer ) ; group 2 : AH Plus ( resin-based sealer ) ; group 3 : self-etch Epiphany ( resin-based sealer ) ; group 4 : Sealer 26 ( calcium hydroxide-based sealer ) ; and group 5 : Endomethasone ( zinc oxide eugenol-based sealer ) . The root canals were filled with gutta-percha , the cold lateral compaction technique , except for group 3 where Resilon was used . Post spaces were prepared , and fibreglass posts were cemented with the self-adhesive cement RelyX Unicem . Bonded specimens were sectioned into 1-mm-thick slabs , and a push-out test was performed in a universal machine . Failure modes were observed and classified into five types : ( i ) adhesive between the post and resin cement ; ( ii ) mixed , with resin cement covering 0 - 50 % of the post diameter ; ( iii ) mixed , with resin cement covering 50 - 100 % of the post surface ; ( iv ) adhesive between resin cement and root canal ; and ( v ) cohesive in dentine . Data of bond strength were su bmi tted to anova and Tukey test ( α = 0.05 ) . RESULTS No significant difference was detected between control group , AH Plus , Epiphany and Sealer 26 ( P > 0.05 ) . The Endomethasone group had significantly lower bond strength values than the other sealers ( P < 0.05 ) . The prevalence of mixed fractures and adhesive cement-dentine failure was verified in the eugenol-containing sealer group ; in the control group , the resin-based and calcium hydroxide-based sealer groups , the predominant mode of failure was the mixed type . CONCLUSION Endomethasone interfered negatively with the bond to root dentine ; however , AH Plus , Epiphany and Sealer 26 did not interfere in the bond strength of a fibreglass post cemented with self-adhesive resin cements Background The aim of this in vitro study was to examine and compare the effect of photodynamic therapy and solution containing nano particles Ag/ZnO on adhesion of endodontic sealers to dentinal walls of human root canal . Material and Methods Ninty single-rooted human teeth were selected and their clinical crown was cut from the cemento-enamel junction zone . Canals were prepared by RaCe rotary system and the smear layer was removed using 17 % EDTA and 5.25 % NaOCl . Sample s were r and omly divided into two groups of AH Plus and MTA Fillapex based on the sealer type and each group based on antimicrobial method was divided into two sub-groups of photodynamic therapy and polymer containing nano particles of Ag / ZnO and a control sub-group ( N = 15 ) . After obturation of canals with gutta-percha and sealers mentioned , the sample s were incubated for a week at a humidity of 95 % and 37 ° C and then 2 mm thick discs were prepared from the middle region of roots for Push-out test . The maximum failure force was recorded in newton and converted to MPa . Then , 3 r and om specimens of each subgroup were evaluated by scanning electron microscopy . Statistical analysis was performed by Two way ANOVA and ( P<0.05 ) was considered significant . Results The highest ( 4.84 ± 1.63 ) and lowest ( 0.16 ± 0.075 ) push-out bond strength values were obtained in ( AH Plus-PDT ) and ( MTA Fillapex-Ag/ZnO ) respectively . Independent of antimicrobial method , AH Plus bond strength was significantly higher than the MTA Fillapex ( p<0.001 ) . For both sealers , PDT  increased the bond strength significantly ( p<0.001 ) . Conclusions Photodynamic therapy has a positive effect on the bond strength of AH Plus and MTA Fillapex sealers . Key words : AH Plus , MTA Fillapex , Nano particles , Photodynamic therapy , Push-out Background : Fiber reinforced composite ( FRC ) posts are cemented with resin cements . It is reported that using resin cements in canals sealed with eugenol-containing sealers reduces the post retention . However , there is controversy on the subject . Aims : The aim was to investigate the influence of eugenol-containing sealers and the amount of dentin removal from root canal with different post diameters on retention of FRC posts . Setting s and Design : It was an in vitro study Material s and Methods : The roots of sixty teeth were cut with 14 mm distance from the apex and were instrumented to the working-length of 13 mm . The teeth were r and omly distributed into 2 groups ( n = 30 ) . Following storage in normal saline for 7 days , the sample s in both the groups were further divided into 3 subgroups ( n = 10 ) . Canals in the experimental subgroups ( I , II , III ) were obturated by gutta-percha and eugenol-containing sealer ; and in the control subgroups ( IV , V , VI ) without any sealer . After storage in normal saline for 7 days , the post space was prepared by # 3 , # 2 , and # 1 drills of DT Light-Post system . Post was cemented with Panavia-F2.0 resin-cement . A composite core was built for each sample . All sample s were thermo cycled for 1000 cycles . The sample s were tested for post retention with a mechanical testing machine . Statistical Analysis : Data were analyzed by two-way ANOVA and Tukey-HSD test . Results : There was not a significant difference in retention between FRC posts # 1 and # 2 ( P > 0.05 ) . Post # 3 was more retentive than posts # 1 and # 2 ( P < 0.05 ) . ZOE sealer significantly reduced the retention of posts ( P = 0.024 ) , however , increasing post-space diameter significantly increased post retention in canals coated with ZOE sealer ( P = 0.002 ) . Conclusions : Eugenol-containing sealer reduced the retention of FRC posts cemented with resin cement . Removing more dentin from root-canals treated with eugenol-containing sealer for placing larger diameter posts caused an increase in post retention The aim of this study was to compare the fracture resistance of roots filled with gutta percha ( GP ) and different root canal sealers .  Fifty-five human maxillary central incisors were selected and r and omly divided into three experimental groups ( Groups 1 - 3 ) and two control groups ( Groups 4 and 5 ) . They were Group 1 - 15 root canals filled with an epoxy resin-based sealer ( AH Plus ) and GP , Group 2 -15 root canals filled with a calcium silicate-based sealer ( iRoot SP ) and GP , Group 3 : 15 root canals filled with another calcium silicate-based sealer ( MTA Fillapex ) and GP , Group 4 : five roots were instrumented but not filled , and Group 5 : five roots were neither instrumented nor filled . Compressive loading was carried out using a universal testing machine until fracture occurred . Force applied at time of fracture was recorded as fracture strength of specimen in Newtons . There were no significant differences in fracture strength among the three experimental groups ( p>0.05 ) , whose results were significantly superior to that of Group 4 ( p<0.05 ) . In conclusion , all the root canal sealers used in the present study increased the fracture resistance of instrumented root canals
In general , studies suggest that root canal sealers elicit mild to severe toxic effects and that several factors may influence biocompatibility , e.g. , material setting condition and time , material concentration , and type of exposure .
4 ) Conclusions : The available evidence shows that root canal sealers exhibit variable toxic potential at the cellular and tissue level .
However , the method ological heterogeneity among studies included in this systematic review and the somewhat conflicting results do not allow a conclusion on which type of sealer presents higher biocompatibility .
( 1 ) Aim : To perform a systematic review of the literature on the biocompatibility of  root canal sealers  that encompasses the various types of sealers that are commercially available as well as both in vitro and in vivo evidence . (