Comparison of Different Dentin Deproteinizing Agents on the Shear Bond Strength of Resin-bonded Dentin.

AIM: To assess and analyze the resin-bonded dentin in terms of shear bond strength after using deproteinizing agents 5% sodium hypochlorite, 10% sodium hypochlorite, and bromelain. MATERIALS AND METHODS: Overall 140 permanent and intact human premolars were split into four groups, three experimental groups and one control group. In all four groups, the occlusal surface of the teeth was wet ground to expose superficial dentin. In group I, teeth were etched and deproteinized with 5% sodium hypochlorite. In group II, teeth were etched and deproteinized with 10% sodium hypochlorite. In group III, teeth were etched and bromelain was used to deproteinize. In group IV, teeth were etched and no deproteinization was being performed and simultaneous fulfillment of the resin composite and later inserted into the plastic tube and polymerized with light. Samples were stored at 37°C for 24 hours and the later samples were transferred to the universal testing machines to shear bond strength analysis at a speed of 0.5 mm/minute. RESULTS: The outcome of the bond strength was significantly influenced by the application of bromelain enzymes. A remarkable difference was observed between the shear bond strength of sodium hypochlorite (5 and 10%) and in the bromelain enzyme-treated group. Group III showed better results than group I and group II. CONCLUSION: This study concluded that bromelain shear has the maximum value for shear bond strength. Bond strength improved because of removal of unsupported collagen fiber with bromelain enzyme after acid etching. CLINICAL SIGNIFICANCE: Natural pineapple enzyme, i.e., bromelain improves bond strength by removal of unsupported collagen fiber. Hence, it is completely safe to use. HOW TO CITE THIS ARTICLE: Khan R, Sharma N, Garg Y, et al. Comparison of Different Dentin Deproteinizing Agents on the Shear Bond Strength of Resin-bonded Dentin. Int J Clin Pediatr Dent 2020;13(S-1):S69-S77.

Comparative Evaluation of Effect of Lasers and Biodentine in Dentine Regeneration: A Clinical Study.

AIM: To compare and evaluate the effect of different liners separately and in combination with lasers that is resin modified glass-ionomer cement (RMGIC), Laser+RMGIC, Biodentine, Laser+Biodentinein the treatment of deep carious lesions. MATERIALS AND METHODS: Forty patients with deep caries indicated for pulp capping were selected. Curative procedure including the cavity preparation with maximal removal of softened dentine using spoon excavator, slow speed handpiece with round burs was performed. Patients were divided into four groups with 10 patients in each group In group A RMGIC liner, group B laser biostimulation followed by RMGIC liner, group C biodentine liner, group D laser biostimulation followed by Biodentine liner were placed in the cavity after caries removal. Cavities were temporarily restored with IRM for 8 weeks. After 8 weeks, liners in each group were removed, and cavities were permanently restored lower half of the cavity with a layer of flowable Z350 XT composite, and then the remaining half of the cavity with P60 filled composites (3 M ESPE, USA) in all the groups. The observation period was 12 months. RESULTS: All the patients showed a positive response to cold test and electric pulp test at 3 months, 6 months, 12 months follow-up. In group A (RMGIC) two patients and in group B (Laser+Biodentine) three patients did not return back for the follow-up. To standardize the samples, seven patients were selected from each group with a total of 28 samples included in the study (n = 7) and statistical analysis was done using analysis of variance (ANOVA) test. The mean for the total amount of dentine deposited after 12 months was highest in: Group D-(Laser+Biodenitne) 0.32 mm > Group C-(Biodentine) 0.25 mm > Group B-(Laser+RMGIC) 0.10 > Group A-(RMGIC) 0.07 mm Conclusion: Within the limitation of the present study the following conclusion was drawn: • Lasers and biodentine are good indirect pulp capping agents • Laser has an additional effect on the tertiary dentine formation. CLINICAL SIGNIFICANCE: Lasers with antibacterial effect penetrate into dentinal tubules and accelerate the rate of dentin bridge formation in deep carious lesions.

An In Vitro Evaluation of Antimicrobial Effects of Three Different Root Canal Irrigating Solutions against Enterococcus faecalis and Streptococcus mutans.

AIM: The present study was conducted to evaluate and compare antimicrobial effect of 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX) and N-Acetylcysteine (NAC) irrigating solutions against Enterococcus faecalis (E. faecalis) and Streptococcus mutans (S.mutans). MATERIALS AND METHODS: The present study was conducted on 40 freshly extracted noncarious permanent mandibular incisors teeth of both genders (males-12, females-14). In all teeth, root canal preparation was done up to size 40 K-file. Roots were sterilized and microbial suspension of mixed culture of the tested microorganisms was inoculated into canals and incubated for 48 h. Teeth were divided into four groups, group I (5.25% sodium hypochlorite), group II (2% chlorhexidine), group III (200 mg/mL N-Acetylcysteine NAC) and group IV (sterile distilled water). The antimicrobial effect in each group was compared. RESULTS: Statistical evaluation was completed using statistical software Statistical Package for the Social Sciences (SPSS). Planktonic S. mutans bacterial count was lowest in group III followed by group I, group II and group IV.E. faecalis count was 6.14 ± 0.12 in group I, 5.76 ± 0.44 in group II, 3.88 ± 0.08 in group III and 11.98 ± 1.04 in group IV. The difference was significant (p < 0.05). The proportion of dead cell found to be 0.04± 0.01, 0.72 ± 0.06, 0.01 ± 0.06 and 1.02 ± 0.11 in groups I, II, III and IV respectively. The difference was significant (p < 0.05). CONCLUSION: NAC proved to be effective against E. faecalis and S. mutans. This solution can be considered alternative in root canal infections in addition with CHX and NaOCl. CLINICAL SIGNIFICANCE: Effectiveness of three different irrigating solutions was compared and NAC found to be more efficient in decreasing bacterial count. Hence, NAC can be precisely used in irrigating root canals to achieve optimal clinical outcomes particularly regarding reoccurrences of infections. Furthermore, NAC could be proved as a promising innovation in future endodontic methodologies.