SUMMARY Objective: A systematic review and meta-analyses were performed to evaluate the efficacy of tooth color change and sensitivity of teeth following in-office bleaching with and without light gel activation in adult patients. Methods: This review was registered at PROSPERO (CRD 42017060574) and is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Electronic systematic searches of PubMed/MEDLINE, Web of Science, and the Cochrane Library were conducted for published articles. Only randomized clinical trials among adults that compared in-office bleaching with and without light activation with the same bleaching gel concentrations were selected. The outcomes were tooth color change and tooth sensitivity prevalence and intensity. Results: Twenty-three articles from 1054 data sources met the eligibility criteria. After title and abstract screening, 39 studies remained. Sixteen studies were further excluded. Twenty-three studies remained for qualitative analyses and 20 for meta-analyses of primary and secondary outcomes. No significant differences in tooth color change or tooth sensitivity incidence were found between the compared groups; however, tooth sensitivity intensity decreased when light sources were applied. Conclusion: The use of light sources for in-office bleaching is not imperative to achieve esthetic clinical results.

SUMMARY The objective of this longitudinal clinical randomized trial was to evaluate the clinical performance of a nanofilled and a nanohybrid resin composite in Class I occlusal restorations of posterior teeth over the course of 54 months. Forty-one adolescents participated in the study. The teeth were restored with Adper Single Bond 2 (3M ESPE) and nanofilled (Filtek Z350, 3M ESPE), nanohybrid (Esthet-X, Dentsply) and microhybrid Filtek Z250 (3M ESPE) used as a control. After 54 months, the restorations were evaluated in accordance with the modified United States Public Health Service criteria. The McNemar and Friedman tests were used for statistical analysis, at a level of significance of 5%. Five failed restorations were observed during the follow-up. A change to unacceptable restoration occurred for one Esthet-X, two Filtek Z350, and two Filtek Z250 restorations, which received the clinically unacceptable score, Charlie, for both anatomic form and marginal adaptation. Secondary caries and postoperative sensitivity occurred in one Filtek Z250 and one Filtek Z350 restoration. When the five evaluation periods (baseline and six, 12, 30, and 54 months) were compared, significant differences were found in the marginal adaptation of Filtek Z250 and Filtek Z350. Significant differences in the roughness criteria ( p =0.005) were also observed when the three composites were compared after 54 months (Filtek Z350 > Filtek Z250 > Esthet-X), always within clinically acceptable limits. The materials investigated showed acceptable clinical performance for Class I restoration after 54 months. Long-term reevaluations are necessary for a more detailed analysis of these composites.

SUMMARY This study aimed to evaluate the bond durability of dentin restorations bonded with light- or dual-cured etch-and-rinse adhesive systems. A three-step adhesive system (Scotchbond Multipurpose Plus), an acetone-based two-step adhesive system (Prime & Bond 2.1), and an ethanol-based two-step adhesive system (Excite) were tested. Both the light- and the dual-cured versions were evaluated. High C-factor dentin cavities were prepared on 120 bovine incisors, which were then restored with resin composite (n=10). The samples were stored in water for 24 hours, and half of them were subjected to additional degradation with 10% NaOCl for five hours. The push-out bond strength test was performed in a universal testing machine until failure. Failure modes were evaluated by scanning electron microscopy. Data were analyzed by three-way analysis of variance and Tukey tests ( p <0.05). The dual-cured adhesive system presented a higher immediate bond strength and durability than those that were light cured. The three-step adhesive system produced the highest values, whereas the acetone-based adhesive system produced the lowest result. Therefore, the use of dual-cured etch-and-rinse adhesive systems can induce increased bond durability to direct coronal dentin restorations.

SUMMARY This study evaluated the effect of five methods of solvent volatilization on the degree of conversion (DC) of nine one-bottle adhesive systems using Fouriertransform infrared/attenuated total reflectance (FTIR/ATR) analysis. Nine adhesives were tested: Adper Single Bond 2 (SB), Adper Easy One (EO), One Up Bond F Plus (OUP), One Coat Bond SL (OC), XP Bond (XP), Ambar (AM), Natural Bond (NB), GO, and Stae. The adhesive systems were applied to a zinc-selenide pellet and 1) cured without solvent volatilization, 2) left undisturbed for 10 seconds before curing, 3) left undisturbed for 60 seconds before curing, 4) air-dried with an air stream for 10 seconds before curing, and 5) air-dried with an air stream for 60 seconds before curing. FTIR/ATR spectra were obtained, and the DC was calculated by comparing the aliphatic bonds/reference peaks before and after light activation for 10 seconds (FlashLite 1401). The DC means of each material were analyzed by one-way analysis of variance and post hoc Tukey test ( p <0.05). The DC of GO and Stae adhesive systems was not affected by the five evaporation conditions. Air-drying for 60 seconds before curing yielded the highest DC for SB, EO, and OC. Extended solvent volatilization time (60 seconds) either with or without air-drying before curing provided the highest DC for AM, NB, XP, and OUP. Thus, the monomer conversion of adhesive systems was material dependent. In general, the 60-second passive or active air-drying modes to volatilize solvents before curing enhanced the degree of conversion for the one-bottle simplified adhesive systems.

SUMMARY This study was designed to evaluate in vitro the efficacy of a novel at-home bleaching technique using 10% or 16% carbamide peroxide modified by casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and its influence on the microhardness of bleached enamel. A total of 40 bovine incisors were divided into four groups (n=10) according to the bleaching agent used: 10% carbamide peroxide only; a blend of 10% carbamide peroxide and a CPP-ACP paste; 16% carbamide peroxide only; and a blend of 16% carbamide peroxide and a CPP-ACP paste. During the 14-day bleaching regimen, the samples were stored in artificial saliva. The Vickers microhardness and color of the teeth were assessed at baseline (T0) and immediately after the bleaching regimen (T14) using a microhardness tester and a spectrophotometer, respectively. The degree of color change was determined by the Commission Internationale de l'Eclariage (CIE) L*a*b* system (ΔE, ΔL*, Δa*, and Δb*) and Vita shade guide parameters. The data were analyzed by analysis of variance and the Tukey test ( p <0.05). The teeth that were bleached with a blend of peroxide (10% or 16%) and the CPP-ACP paste presented increased microhardness values at T14 compared with T0, whereas the samples that were bleached with peroxide only did not show any differences in their microhardness values. All of the bleaching agents were effective at whitening the teeth and did not show a statistically significant difference using the CIEL*a*b* system (ΔE, ΔL*, Δa*, and Δb*) or the Vita shade guide parameters. The use of a CPP-ACP paste with carbamide peroxide bleaching agents increased the bleached enamel's microhardness and did not have an influence on whitening efficacy.