Influence of bioceramic cones on the quality of root canal filling relative to bond strength and adaptation of the adhesive interface.

AIM: To evaluate the bond strength (BS) and analysis of the adhesive interface in root canals filled with bioceramic gutta percha sealers and cones. MATERIAL AND METHODS: Ninety-six maxillary canines were divided into eight groups according to the endodontic sealer (AH Plus, AH Plus Bioceramic, Bio-C Sealer or Bio-C Sealer Ion+ and gutta percha cones (conventional or bioceramic) tested. They were analyzed using the BS test, failure pattern, analysis of the adhesive interface by scanning electron microscopy and confocal laser scanning microscopy. The BS data were compared between groups using the analysis of variance test with the Turkey post-test. The chi-square test was used to assess the type of failure and the non-parametric Mann-Whitney and Kruse-Wallis tests (P < 0.05). RESULTS: Analysis of variance showed higher BS values for the groups of bioceramic gutta percha cones in Bio-C Sealer Ion+ (8.38 ± 4.27), AH Plus Bioceramic (6.19 ± 3.28), Bio-C Sealer (5.70 ± 3.18), AH Plus (4.61 ± 2.11) and for conventional gutta percha cones in AH Plus sealers (4.26 ± 2.35), Bio-C Sealer Ion + (3.63 ± 2.29), Bio-C Sealer (2.94 ± 2.32) and AH Plus Bioceramic (1.19 ± 0.89) (P < 0.05). Relative to the type of failure and adaptation of the types of filling material, a higher percentage of mixed failures was observed (gaps between 1 µm-10 µm) for the group with bioceramic gutta percha cones (P < 0.001). CONCLUSION: The bond between sealers and bioceramic gutta percha cones showed higher bond strength values and greater penetration into the dentin tubules. CLINICAL RELEVANCE: The filling the root canal system with bioceramic sealers should be associated with bioceramic gutta percha cones.

Micro-Morphological Features of the Er:YAG-Lased Interface in Primary Teeth: 12 Months Randomized Split-Mouth Trial.

Despite considerable improvements in oral health, dental caries remains a public health issue. The most frequently used technique to remove caries is through rotating drills. New minimally invasive strategies were introduced into dental practice, such as the use of lasers to perform highly controlled tissue ablation while limiting pain and discomfort, as well as overcoming drill phobia. The objective was to assess and compare treatment with Er:YAG laser versus a conventional rotary treatment during cavity preparation in children with regard to bond interface quality. In a randomized trial using a split-mouth design, 40 (9-12 year-old) children with 80 carious primary molars were included. The cavity in one quadrant was treated conventionally using a bur, while the cavity in the other quadrant was prepared using an Er:YAG laser. Twenty restored teeth were extracted after one year. The SEM histological evaluation of bond interface results demonstrated no statistically significant differences between restorations placed following bur preparation and those placed following the Er:YAG laser preparation, and both treatments demonstrated promising results. Over a one-year period, no statistically significant differences in the bond interface quality were observed following class I cavity preparation in primary teeth with either Er:YAG laser or a conventional rotary bur.

Effects of caffeic acid phenethyl ester application on dentin MMP-2, stability of bond strength and failure mode of total-etch and self-etch adhesive systems.

OBJECTIVE: Investigate the long-term effect of dentin pretreatment with 0.05 or 0.1% caffeic acid phenethyl ester (CAPE) on (1) bond strength of resin composite to dentin by a three-step etch-and-rinse (Adper Scotchbond Multipurpose/ ASB) or a two-step self-etch adhesive system (Clearfil SE Bond/ CSE), (2) their fracture mode, (3) the micromorphological features of the hybrid layer formed; and (4) the level of MMP-2 in dentin (after application, using a correlative immunoexpression/quantification approach). DESIGN: Composite resin blocks were fabricated on 48 third molars (n = 6), according to the type of adhesive and treatment (control, CAPE 0.05% and CAPE 0.1%). Slices were obtained for scanning electron microscopy (SEM) evaluation, and sticks were fabricated for microtensile tests (24 h and 1 year). Aliquots of dentin powder were distributed (n = 12) according to the treatment and the MMP-2 concentration was determined by ELISA. RESULTS: Tukey test showed that ASB groups presented higher BS in 24 h than CSE groups. ASB presented a reduction in BS values after 1-year. ASB and CSE presented no significant differences in BS after 1-year. CAPE had no effect on BS for both adhesive systems. The predominant failure mode for the ASB groups were adhesive; when 0.1% CAPE was applied there was a predominance of mixed fractures. Regarding the CSE group, 0.05% CAPE led to more adhesive failures, and the 0.1% concentration resulted in a higher number of cohesive failures in dentin. Higher MMP-2 concentrations were detected for the groups that did not undergo demineralization treatment, and the lowest values for the ASB groups treated with CAPE. SEM analysis showed no influence of pretreatment with CAPE. CONCLUSIONS: CAPE did not influence the BS of the adhesives tested, or the micromorphology of the hybrid layer, irrespective of concentration or storage time. CAPE affected the fracture pattern at 24 h, depending on the concentration and the adhesive system used. Immunoassay analysis showed that CAPE 0.1% reduced the MMP-2 concentration in the ASB adhesive without affecting bond strength to dentin.