Shear bond strength and SEM morphology evaluation of different dental adhesives to enamel prepared with ER:YAG laser.

CONTEXT: Early observations of enamel surfaces prepared by erbium lasers motivated clinicians to use laser as an alternative to chemical etching. AIMS: Evaluate shear bond strength (SBS) values of different dental adhesives on Erbium:Yttrium Aluminum Garnet (Er:YAG) laser prepared enamel and to evaluate possible etching patterns correlations between dental adhesives and SBS values. SUBJECTS AND METHODS: One hundred bovine incisors were randomly assigned to SBS tests on enamel (n = 15) and to enamel morphology analysis (n = 5) after Er:YAG laser preparation as follows: Group I - 37% phosphoric acid (PA)+ ExciTE(®); Group II - ExciTE(®); Group III - AdheSE(®) self-etching; Group IV - FuturaBond(®) no-rinse. NR; Group V - Xeno(®) V. Teeth were treated with the adhesive systems and subjected to thermal cycling. SBS were performed in a universal testing machine at 5 mm/min. STATISTICAL ANALYSIS USED: One-way ANOVA and post-hoc tests (P < 0.05). For the morphology evaluation, specimens were immersed in Ethylenediamine tetraacetic acid (EDTA) and the etching pattern analyzed under Scanning Electron Microscope (SEM). RESULTS: Mean bond strengths were Group I - 47.17 ± 1.61 MPa (type I etching pattern); Group II - 32.56 ± 1.64 MPa, Group III - 29.10 ± 1.34 MPa, Group IV - 23.32 ± 1.53 MPa (type III etching pattern); Group V - 24.43 MPa ± 1.55 (type II etching pattern). CONCLUSIONS: Different adhesive systems yielded significantly different SBSs. Acid etching significantly increased the adhesion in laser treated enamel. No differences in SBS values were obtained between AdheSE(®) and ExciTE(®) without condition with PA. FuturaBond(®) NR and Xeno(®) V showed similar SBS, which was lower in comparison to the others adhesives. No correlation between enamel surface morphology and SBS values was observed, except when PA was used.

Esthetic rehabilitation of anterior conoid teeth: comprehensive approach for improved and predictable results.

The esthetic success of a dental treatment depends on the correct diagnosis, treatment plan and clinical and laboratory procedures. This clinical report describes a diagnostically based protocol for conservative preparations on anterior teeth for adhesively retained composite and porcelain restorations. The diagnostic additive wax-up, periodontal esthetic crown-lengthening, direct acrylic mock-up, conservative preparations for ceramic laminate veneers, luting procedures, direct restorations with composite resin used for the esthetic rehabilitation of a patient presenting conoid lateral incisors, and an unsatisfactory class IV restoration in the left central incisor are presented. An accurate diagnostic and interdisciplinary approach is necessary for obtaining improved, conservative and predictable esthetic results in esthetically compromised areas, such as the anterior maxillary dentition.

Effect of bur type on microtensile bond strengths of self-etching systems to human dentin.

PURPOSE: To compare the microtensile bond strength (microTBS) of five adhesives to human dentin prepared with 600-grit SiC abrasive paper (SiC), a diamond rotary instrument, or a carbide bur. The null hypothesis was that different cavity preparation instruments do not affect adhesion of resin adhesives. MATERIALS AND METHODS: Human molars (n = 45) were randomly divided into three groups according to surface treatment. Each group was bonded using a total-etch adhesive (Single Bond, 3M ESPE), one of three self-etching primer systems (Clearfil SE Bond or ABF, Kuraray; Imperva Fluorobond, Shofu), or a self-etching adhesive (One-Up Bond F, Tokuyama). A 4-mm composite crown was built over the bonded surface. Specimens were stored in water for 24 h at 37 degrees C. They were sectioned into 0.7-mm-thick slabs, trimmed to a cross-sectional area of 1 mm2, and loaded to failure at a crosshead speed of 1 mm/min using a tabletop tester (EZ-Test, Shimadzu). Microtensile bond strength data were analyzed using analysis of variance and Fisher's PLSD test. RESULTS: Surface preparation using a carbide bur generally yielded higher bond strengths than preparation using either a diamond rotary instrument or SiC abrasive paper. SE Bond had the highest mean microTBS of the five adhesives tested. CONCLUSION: Resin-dentin bond strengths can be affected by the type of instrument used to prepare the tooth. Specifically, higher bond strengths might be achieved by using carbide burs rather than diamond cutting instruments.

Effect of surface preparation on microtensile bond strength of three adhesive systems to bovine enamel.

PURPOSE: The purpose of this study was to compare the microtensile bond strength (microTBS) of three adhesives to bovine enamel prepared with 600-grit silicon carbide paper, diamond rotary instrument, or carbide bur. MATERIALS AND METHODS: Bovine teeth (n = 36) were randomly divided into three treatment groups and bonded using a total-etch adhesive (Single Bond, 3M ESPE), a self-etching primer system (Clearfil SE Bond, Kuraray), or a self-etching adhesive (One-Up Bond F, Tokuyama). A 4-mm composite crown was built on the bonded surfaces and specimens were stored in water for one day at 37 degrees C. Specimens were sectioned into 0.7-mm-thick slabs, trimmed to a cross-sectional area of 1 mm2, and loaded to failure at a crosshead speed of 1 mm/min using a tabletop tester (EZ-Test, Shimadzu). Microtensile bond strength data were analyzed using ANOVA and Fisher's PLSD test (alpha = 0.05). RESULTS: The bond strength of each self-etching system was lower when the enamel was prepared using a diamond or carbide bur, rather than with 600-grit silicon carbide paper. Differences in microTBS between carbide- and diamond-prepared surfaces were not significant. The surface preparation method did not affect the total-etch system. CONCLUSION: Different preparation instruments are unlikely to affect resin-enamel bond strengths.

Repairability of a packable resin-based composite using different adhesives.

PURPOSE: To compare the repair potential of a packable composite (Filtek P60) to that of a conventional hybrid composite (Pertac II) using three different adhesives: an unfilled resin (EBS-Multi), a one-bottle, acetone-based adhesive (One-Step), and a self-etching adhesive (Prompt L-Pop). MATERIALS AND METHODS: 30 composite disks (diameter = 8 mm) of each composite material were fabricated, light-cured, and stored in 37 degrees C for 7 days. The specimens were polished to 600-grit, sandblasted (CoJet-System), silanated, and randomly assigned to three groups (n=10). EBS-Multi, One-Step, and Prompt L-Pop were applied to each composite and cured. Pertac II was applied in a #5 gelatin capsule and light-cured. As controls, Pertac II was applied to freshly cured Filtek P60 and Pertac II specimens, with no additional surface treatment. Specimens were loaded in shear using an Instron testing machine at a crosshead speed of 5 mm/minute, 24 hours after bonding, and the peak shear force at failure was converted to MPa (force/area). RESULTS: ANOVA showed a significant difference in means at P<0.001. Tukey's test was used for pairwise comparisons. Mean SBS (+/-SD, MPa) were: P60/control: 25.2 (3.0); P60/EBS-Multi: 18.0 (2.3); P60/One-Step: 16.7 (2.3); P60/Prompt: 10.5 (3.3); Pertac/control: 25.5 (3.6); Pertac/EBS-Multi: 18.8 (3.0); Pertac/One-Step: 18.8 (2.4); Pertac/Prompt: 9.7 (3.5). Repair strengths were all significantly less than their respective controls, and repairs made using Prompt L-Pop had significantly lower mean strengths than the repairs made with EBS-Multi and One-Step (P<0.05).