Disinfection of dentinal tubules with 2% Chlorhexidine gel, Calcium hydroxide and herbal intracanal medicaments against Enterococcus faecalis: An in-vitro study.

AIM: This in vitro study was conducted to evaluate the disinfection of dentinal tubules using 2% Chlorhexidine gel, Honey, Aloe vera gel, Curcuma longa, Propolis gel and Calcium hydroxide against Enterococcus faecalis. MATERIALS AND METHOD: Two hundred and ten human mandibular first premolars were infected with Enterococcus faecalis for 21 days. Samples were divided into 7 groups. Group I- Saline (negative control), Group II- 2% Chlorhexidine gel(CHX), Group III- honey, Group IV- Aloe vera gel, Group V- 20% Curcuma longa gel, Group VI- Propolis gel and Group VII -Calcium hydroxide (CH). At the end of 1, 3 and 5 days, the antimicrobial efficacy of medicaments against E.faecalis was assessed at the depths of 200µm and 400µm. RESULTS: 2% Chlorhexidine gel was most effective followed by Propolis and Curcuma longa. CONCLUSION: 2% Chlorhexidine gel gave the best results. Among the herbal extracts Propolis and Curcuma longa hold a promising future but to implement their use as sole intracanal medicaments clinically, further in vivo and long term studies are warranted.

Comparative evaluation of the effect of chlorhexidine and Aloe barbadensis Miller (Aloe vera) on dentin stabilization using shear bond testing.

INTRODUCTION: The main objective of adhesive dentistry is to create an effective, durable union between the tooth structure and restorative material. However, degradation of adhesive dentine interface remains largely responsible for the relatively short lifetime of tooth colored resin restoration. AIM: The aim of the study is to compare the dentin collagen stabilization property of Chlorhexidine (CHX) and Aloe barbadensis Miller using shear bond strength testing. MATERIALS AND METHODS: Occlusal reduction was done in sixty extracted human mandibular molars to expose the mid coronal dentin and divided into three groups n = 20. Following the surface pretreatment (Group 1 = control, Group 2 = CHX, Group 3 = Aloevera), dentine bonding agent and composite resin were applied and cured. The specimens were then subjected to shear bond strength testing. RESULTS: From the results analyzed, it was noted that there was statistically significant difference between the groups Control and CHX and Control and A. barbadensis Miller (P < 0.05), specifically the values of Control < CHX and Control < A. barbadensis Miller (P < 0.05). However, there was no statistically significant difference between CHX and A. barbadensis Miller (P > 0.05). Hence, the following result for the shear bond strengths to dentin was obtained: Control < CHX ≈ A. barbadensis Miller. CONCLUSION: CHX and A. barbadensis Miller, as pretreatment agents of acid demineralized dentin collagen, has no adverse effect on the immediate shear bond strength of a two-step etch and rinse adhesive to dentin.

The shear bond strength of MTA with three different types of adhesive systems: An in vitro study.

AIM: To evaluate the shear bond strength of MTA with three different types of adhesive systems- self-adhering flowable composite, etch and rinse adhesive system and self etch adhesive system. METHODOLOGY: MTA specimens (n = 60) were prepared using cylindrical acrylic blocks, having a central cavity with 4 mm diameter and 2 mm depth. MTA was mixed and placed in the prepared cavity, and was covered with a moist cotton pellet and temporary filling material. The specimens were divided into 3 groups which were further divided into 2 sub-groups (45 Minutes and 24 hours). After the application of bonding agents composite resin was placed over the MTA surface. The specimens were tested for shear bond strength and readings were statically analyzed. RESULT: After 24 hrs the mean value of etch and rinse group was significantly higher than self etch and the self adhering composite groups. Among the 45 minutes groups there were no significant difference. CONCLUSION: In single visit after 45 minutes self adhering flowable can be used successfully as a final restorative material in place of conventional flowable composite without using any alternative adhesive system over MTA.

Effect of EDTA Conditioning and Carbodiimide Pretreatment on the Bonding Performance of All-in-One Self-Etch Adhesives.

Objective. This study evaluated the effect of ethylenediaminetetraacetic acid (EDTA) conditioning and carbodiimide (EDC) pretreatment on the shear bond strength of two all-in-one self-etch adhesives to dentin. Methods. Flat coronal dentin surfaces were prepared on one hundred and sixty extracted human molars. Teeth were randomly divided into eight groups according to two different self-etch adhesives used [G-Bond and OptiBond-All-In-One] and four different surface pretreatments: (a) adhesive applied following manufacturer's instructions; (b) dentin conditioning with 24% EDTA gel prior to application of adhesive; (c) EDC pretreatment followed by application of adhesive; (d) application of EDC on EDTA conditioned dentin surface followed by application of adhesive. Composite restorations were placed in all the samples. Ten samples from each group were subjected to immediate and delayed (6-month storage in artificial saliva) shear bond strength evaluation. Data collected was subjected to statistical analysis using three-way ANOVA and post hoc Tukey's test at a significance level of p < 0.05. Results and Conclusion. EDTA preconditioning as well as EDC pretreatment alone had no significant effect on the immediate and delayed bond strengths of either of the adhesives. However, EDC pretreatment on EDTA conditioned dentin surface resulted in preservation of resin-dentin bond strength of both adhesives with no significant fall over six months.

Bonding efficacy of etch-and-rinse adhesives after dentin biomodification using ethanol saturation and collagen cross-linker pretreatment.

AIM: To evaluate whether the application of two simplified etch-and-rinse adhesives to biomodified dentin using ethanol-wet bonding (EWB) and collagen cross-linker (CCL) pretreatment improves their sealing ability. MATERIALS AND METHODS: In 176 extracted human molars, the pulp-chambers were deroofed, and teeth were sectioned horizontally. Samples were randomly divided into eight groups according to four bonding techniques using two simplified etch-and-rinse adhesives; Adper Single Bond 2 (ASB) and XP Bond (XPB). The bonding protocols included: (a) Water-wet bonding (WWB); (b) EWB; (c) WWB and CCL application; (d) EWB and CCL application. After composite resin restorations, dye leakage evaluation and scanning electron microscope analysis were done. Leakage scores were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests at a significance level of P < 0.05. RESULT: For both ASB and XPB adhesives, least dye leakage was observed in EWB groups (b and d) (P = 0.918 and P = 0.399 respectively) which showed no significant difference, while maximum leakage scores were seen in WWB groups (a and c). Regardless of CCL application and adhesives used, EWB technique depicted (P = 0.003 and P = 0.004) significantly greater sealing ability than WWB. CONCLUSION: Bonding of ASB and XPB using EWB significantly improved their sealing ability. Biomodification using CCL pretreatment had no significant effect on the sealing ability of adhesives bonded with either WWB or EWB.

Comparative evaluation of adequacy of final working length after using Raypex5 or radiography: an in vivo study.

AIM: The aim of this clinical study was to compare the effect of working length (WL) determination using electronic apex locator (EAL) or WL radiograph on the length adequacy of final WL. MATERIALS AND METHODS: A total of 153 patients with 153 teeth with single canal were randomized into two groups; in Group 1, the WL was determined by WL radiograph; whereas in Group 2, it was determined by the Raypex5 EAL (VDW, Munich, Germany). Length adequacy was assessed in each group for master cone and categorized into short, acceptable, and over cases. STATISTICAL ANALYSIS USED: The data were statistically analyzed using the Pearson chi-square test at a significance level of P < 0.05. RESULTS: There was no statistically significant difference between the groups in the rates of acceptable (Group 1 = 83.1% and Group 2 = 92.1%) and short cases (Group 1 = 3.9% and Group 2 = 5.2%). Over cases in master cone radiography were significantly more in Group 1 (13.1%) than Group 2 (2.6%) (P = 0.017). CONCLUSION: The results of our study have shown that under clinical condition, success of Raypex5 was comparable to the radiographic WL determination technique in terms of acceptable and short cases. However, there were significantly lesser over cases in EAL group, showing that EALs can avoid the overestimation of WL.

Root and canal morphology of maxillary first premolar teeth in north Indian population using clearing technique: An in vitro study.

AIM: The purpose of this study was to determine the root form and canal configuration in maxillary first premolars. MATERIALS AND METHODS: A total of 250 extracted human adult maxillary first premolar teeth from North Indian population were collected. Access cavities were prepared and the coronal pulp tissue was extirpated. The samples were stored in 5% nitric acid solution for 5 days. They were then rinsed, dried, and dehydrated using increasing concentrations of ethanol (70, 80, and 95%) successively for 1 day. Teeth were rendered transparent by immersing in methyl salicylate. India ink was then injected. The root canal morphology was examined under stereomicroscope. RESULT: 53.6% were single rooted followed by fused root form followed by two root form. 0.4% had three rooted maxillary first premolar. Variable root canal configurations were also found. Type IV configuration was most prevalent (33.2%). Two teeth showed an additional configuration. Lateral canals were present in 34.8% of the samples and intercanal communications in 16%. CONCLUSION: Within the limitations of this study, it was concluded that in North Indian population, there was an increased propensity for types IV, I, II, and III canal morphologies in maxillary first premolars. Single root form was most common.

Influence of double application technique on the bonding effectiveness of self-etch adhesive systems.

AIM: To evaluate and compare the effect of double-application of single-step self-etch adhesives using microleakage study and to analyze the dentin-adhesive interfacial micromorphology. METHODS: In total, 72 extracted human premolars were divided into three groups for different self-etch adhesives (G Bond, GC [GB], Optibond, Kerr [OB], and Xeno V Plus, Dentsply [XV]). Class V cavities were prepared. Each group was further divided into two subgroups (n = 10) according to the placement technique of the adhesive, using the single-application [subgroup (a)] or double-application method [subgroup (b)]. Resin composite (Z 250, 3M ESPE, St. Paul, MN) was used to restore the cavities and light cured for 40 s. Twenty samples from each group were subjected to microleakage study. Two samples from both the subgroups of the three adhesives were used for scanning electron microscopic examination of the resin-dentin interfacial ultrastructure. Dye leakage scores were subjected to statistical analysis using Kruskal-Wallis and Mann-Whitney U-tests at significance level of P < 0.05. RESULTS: GB depicted significantly more microleakage which was significantly greater than OB and XV. The double application led to significant decrease in microleakage of GB with no significant effect on the microleakage scores of other two all-in-one adhesives, that is OB and XV. CONCLUSION: Double application of all-in-one self-etch adhesives improves the marginal sealing ability in dentin although it appears to be product dependent.

Influence of cervical preflaring using different rotary instruments on the accuracy of apical file size determination: A comparative in-vitro study.

AIM: To investigate the influence of cervical preflaring using different rotary instruments on apical file size determination. MATERIALS AND METHODS: Extracted human molar teeth were randomly divided in to eight groups (N = 10): Control group (CG); LA Axxess group (LA); HyFLex group (HF); GatesGlidden group (GG); ProTaper group (PT); Race group(RC); FlexMaster group (FM); and K3 group (K3). Patency was maintained and working length was established under magnification. All instruments were used according to manufacturer's instructions. Steriomicroscopic images were taken to determine the discrepancies in diameters. ProPlus software (USA) was used to determine the diameter of the root canal. ANOVA test and Post Hoc Tests-Bonferroni Multiple Comparisons were used for statistical analysis. RESULTS: Canals preflared with LA Axxess burs showed the best results. Control group that is, the canals with no cervical preflaring showed the maximum discrepancy between the initial apical file diameter and apical canal diameter. CONCLUSION: Cervical preflaring plays an important role in reducing the discrepancy between initial apical file diameter and apical canal diameter.

In vitro bonding effectiveness of three different one-step self-etch adhesives with additional enamel etching.

AIM: To evaluate the effect of additional enamel etching on the shear bond strength of three self-etch adhesives. METHODS: Class II box type cavities were made on extracted human molars. Teeth were randomly divided into one control group of etch and rinse adhesive and three test groups of self-etch adhesives (Clearfil S3 Bond, Futurabond NR, Xeno V). The teeth in the control group (n = 10) were treated with Adper™ Single Bond 2. The three test groups were further divided into two subgroups (n = 10): (i) self-etch adhesive was applied as per the manufacturer's instructions; (ii) additional etching of enamel surfaces was done prior to the application of self-etch adhesives. All cavities were restored with Filtek Z250. After thermocycling, shear bond strength was evaluated using a Universal testing machine. Data were analyzed using anova independent sample's 't' test and Dunnett's test. The failure modes were evaluated with a stereomicroscope at a magnification of 10×. RESULTS: Additional phosphoric acid etching of the enamel surface prior to the application of the adhesive system significantly increased the shear bond strength of all the examined self-etch adhesives. CONCLUSIONS: Additional phosphoric acid etching of enamel surface significantly improved the shear bond strength.

Comparison of antimicrobial efficacy of propolis, Morinda citrifolia, Azadirachta indica (Neem) and 5% sodium hypochlorite on Candida albicans biofilm formed on tooth substrate: An in-vitro study.

INTRODUCTION: Endodontic infections are polymicrobial in nature. Candida albicans is the most common fungus isolated from failed endodontic cases. The constant increase in antibiotic resistant strains and side-effects caused by synthetic drugs has prompted researchers to look for herbal alternatives such as propolis, Morinda citrifolia and Azadirachta indica (Neem) etc., since, the gold standard for irrigation, i.e., sodium hypochlorite has many disadvantages. MATERIALS AND METHODS: Extracted human mandibular premolars were biomechanically prepared, vertically sectioned, placed in tissue culture wells exposing the root canal surface to C. albicans grown on Sabouraud Dextrose Agar to form a biofilm. At the end of 2 days, all groups were treated with test solutions and control for 10 min and evaluated for Candida growth and number of colony forming units. The readings were subjected to statistical analysis using analysis of variance and post hoc Tukey tests. RESULTS: Sodium hypochlorite and propolis groups exhibited highest antimicrobial efficacy against C. albicans with no statistically significant difference. It was followed by the A. indica (Neem) group. M. citrifolia had limited antifungal action followed by the negative control group of saline. CONCLUSION: According to the results of this study, propolis can be used as an effective antifungal agent similar to that of sodium hypochlorite, although long-term in vivo studies are warranted.

Long-term bonding effectiveness of simplified etch-and-rinse adhesives to dentin after different surface pre-treatments.

OBJECTIVE: To evaluate the effect of 2% chlorhexidine (CHX) and 30% proanthocyanidin (PA) application on the immediate and long-term bond strength of simplified etch-and-rinse adhesives to dentin. MATERIALS AND METHODS: One hundred twenty extracted human molar teeth were ground to expose the flat dentin surface. The teeth were equally divided into six groups according to the adhesives used, either Tetric N Bond or Solobond M and pretreatments given either none, CHX, or PA. Composite cylinder was bonded to each specimen using the respective adhesive technique. Half the samples from each group (n = 10) were then tested immediately. The remaining samples were tested after 6 month storage in distilled water. RESULTS: The mean bond strength of samples was not significantly different upon immediate testing being in the range of 8.4(±0.7) MPa. The bond strength fell dramatically in the control specimens after 6 month storage to around 4.7(±0.33) MPa, while the bond strength was maintained in the samples treated with both CHX and PA. CONCLUSION: Thirty percent PA was comparable to 2% CHX with respect to preservation of the resin dentin bond over 6 months.

Effect of different root canal irrigants on the sealing ability of two all-in-one self-etch adhesives: An in vitro study.

AIM: To evaluate the effect of different root canal irrigants on the sealing ability of two self-etch adhesives, using dye penetration method, within the pulp chamber. MATERIALS AND METHODS: 72 extracted human molars were divided into six groups, according to the irrigant and self-etch adhesives used. After de-roofing the pulp chamber with a carborundum disc, the pulp was extirpated using excavator and broaches. In 36 samples, pulp chambers were bonded with Xeno V after irrigation with either 2% CHX (Group1: Xe-CHX) ; 17% EDTA + 5.25% NaOCl (Group2: Xe- EDTA + NaOCl) or normal saline (Group3: Xe-NS) and in other half samples, pulp chambers were bonded with Adper Easy One after irrigation with either 2% CHX (Group 4: Ad-CHX); 17%EDTA + 5.25% NaOCl (Group5: Ad-EDTA+NaOCl) or normal saline (Group 6: Ad-NS). All the samples were restored with Filtek Z350. Ten teeth from each group were assessed for dye penetration. Two samples in each group were viewed under scanning electron microscope to observe resin-dentin interfacial adaptation. Data was statistically analyzed using Mann-Whitney and Kruskal Wallis tests at a significance level of P < 0.05. RESULTS: MEAN MICROLEAKAGE SCORES AND STANDARD DEVIATION OBSERVED WERE: Group 1 (Xe-CHX): 2.8 ± 0.42, Group 2 (Xe-EDTA + NaOCl): 2.3 ± 0.82, Group 3 (Xe-NS): 2.9 ± 0.31, Group 4 (Ad-CHX): 1.2 ± 0.91, Group 5 (Ad-EDTA + NaOCl): 0.8 ± 0.63, Group 6 (Ad-NS): 1.9 ± 0.99. CONCLUSIONS: Adper Easy One showed significantly less leakage than Xeno V when normal saline was used as an irrigant. EDTA treatment followed by NaOCl application significantly reduced microleakage and improved the interfacial adaptation with Adper Easy One. CHX did not significantly affect the sealing ability of both one-step self-etch adhesives tested.

In vitro bonding effectiveness of self-etch adhesives with different application techniques: A microleakage and scanning electron microscopic study.

AIM: To evaluate and compare the microleakage of self-etch adhesives placed under different clinical techniques and to analyze the resin-dentin interfacial ultrastructure under scanning electron microscope (SEM). MATERIALS AND METHODS: 100 extracted human premolars were divided into two groups for different adhesives (Clearfil S(3) and Xeno III). Class V cavities were prepared. Each group was further divided into four subgroups (n = 10) according to the placement technique of the adhesive, i.e. according to manufacturer's directions (Group 1), with phosphoric acid etching of enamel margins (Group 2), with hydrophobic resin coat application (Group 3), with techniques of both groups 2 and 3 (Group 4). The cavities were restored with composite. Ten samples from each group were subjected to microleakage study. Five samples each of both the adhesives from groups 1 and 3 were used for SEM examination of the micromorphology of the resin-dentin interface. RESULTS: At enamel margins for both the adhesives tested, groups 2 and 4 showed significantly lesser leakage than groups 1 and 3. At dentin margins, groups 3 and 4 depicted significantly reduced leakage than groups 1 and 2 for Xeno III. SEM observation of the resin-dentin interfaces revealed generalized gap and poor resin tag formation in both the adhesives. Xeno III showed better interfacial adaptation when additional hydrophobic resin coat was applied. CONCLUSIONS: In enamel, prior phosphoric acid etching reduces microleakage of self-etch adhesives, while in dentin, hydrophobic resin coating over one-step self-etch adhesives decreases the microleakage.