Anderson Gomes Forte

Objectives: To evaluate the effect of thermocycling on the optical and mechanical properties of universal resin composites, with emphasis on color stability, Knoop microhardness, flexural strength, flexural modulus, and filler characteristics. Methods: Four composite resins: Filtek Z250 XT (FZ), Vittra APS Unique (VT), Spectra Smart (SS), and Harmonize (HZ) were evaluated (n = 10 per group). Specimens were subjected to thermocycling (10,000 cycles; 5–55 °C). Color and Knoop microhardness were measured before and after aging (repeated measures), while flexural strength and modulus were determined using independent specimens. Color differences were calculated using the CIEDE2000 formula. SEM/EDS analyses were performed for filler characterization. Statistical significance was set at α = 0.05. Results: Thermocycling significantly affected all evaluated properties (p < 0.05), with a material-dependent response. All materials exhibited ΔE₀₀ values above clinically acceptable thresholds after aging. SS showed the lowest color variation, while VT presented the highest values. In terms of mechanical behavior, FZ and HZ exhibited greater reductions in flexural strength (> 50%) and microhardness (≈ 30–45%), whereas SS demonstrated the highest stability and VT showed intermediate performance. Additionally, FZ and HZ presented flexural strength values below 80 MPa after thermocycling. Conclusions: Thermocycling resulted in clinically relevant color changes in all evaluated universal resin composites, exceeding perceptibility and acceptability thresholds. Additionally, mechanical properties were adversely affected in a material-dependent manner, with reductions in flexural strength and microhardness suggesting decreased structural stability after aging. Clinical Significance: Universal resin composites may exhibit clinically relevant color changes and significant mechanical degradation after aging. Clinicians should consider that materials with greater reductions in flexural strength and microhardness may present reduced durability over time.

To map and summarize scientific evidence on engineered scaffolds for dentin–pulp complex regeneration. This scoping review followed the PRISMA-ScR guidelines and was registered in the Open Science Framework. Systematic searches were conducted in PubMed, Embase, Scopus, and Web of Science, complemented by grey literature searches. In vitro, in situ, and in vivo studies that evaluated scaffolds or other biomaterial-based strategies for guided tissue regeneration in the dentin–pulp complex were included. Two reviewers independently performed study selection, data extraction, and qualitative descriptive synthesis. Of the 357 records identified after duplicate removal, 44 met the inclusion criteria and were included in the qualitative synthesis. Most were in vitro studies, followed by combined in vitro/in vivo and in vivo animal studies. The scaffolds included synthetic polymers, natural biomaterials, bioceramics, hybrid systems, and extracellular matrix-derived materials. Lyophilization and electrospinning were the most common fabrication techniques, although 3D printing, bioprinting, injectable systems, and self-assembling platforms were also explored. Overall, the studies showed favorable cytocompatibility, supporting cell adhesion, proliferation, migration, odontogenic differentiation, mineralized matrix deposition, and angiogenic potential. Bioactive functionalization further enhanced regenerative performance, while antimicrobial approaches demonstrated activity against clinically relevant endodontic pathogens and inhibition of biofilm formation. In vivo findings supported the formation of vascularized pulp-like tissue and dentin-like or mineralized structures, although the overall evidence remains predominantly preclinical. Scaffolds show potential for dentin–pulp regeneration by providing structural support and bioactive cues. Natural, synthetic, and hybrid systems consistently promote differentiation, mineral deposition, and pulp-like tissue formation.

Erosive tooth wear is a progressive condition that compromises enamel structure and requires preventive strategies. This in vitro study aimed to compare the protective effects of fluoride‐based dentifrices containing various bioactive agents on sound enamel subjected to simulated erosive–abrasive challenges. Sixty bovine enamel blocks were randomly assigned to five dentifrices containing: bioactive silica + 1100 ppm F ⁻ from sodium fluoride (BAS/NaF), 0.454% stannous fluoride (SnF), sodium‐calcium phosphosilicate + 1426 ppm F ⁻ from sodium fluoride (SCP/NaF), 1100 ppm F ⁻ from sodium fluoride (NaF), and a fluoride‐free (FF) control. Specimens underwent 7 days of pH cycling, including three daily acid challenges and 2‐min immersion in dentifrice slurries including 15 s brushing. Measurements included surface microhardness, surface roughness, fluorescence loss, and surface loss. Between‐group differences were assessed using one‐way anova with Tukey post hoc tests. The BAS/NaF and SnF dentifrices outperformed the other formulations, maintaining higher surface hardness and lower surface loss and fluorescence loss ( p < 0.05). The NaF and the SCP/NaF dentifrices showed intermediate results. The fluoride‐free dentifrice exhibited the highest mineral loss. Dentifrices combining fluoride with bioactive ingredients enhanced enamel resistance to erosive–abrasive challenges, with bioactive silica and stannous fluoride showing the strongest effects.

Background: Ready‐to‐drink (RTD) alcoholic beverages often contain organic acids that lower pH and promote enamel demineralization, yet their erosive potential remains insufficiently explored. Objective: This study aimed to evaluate the erosive potential of RTDs through chemical characterization and analysis of enamel surface alterations. Methods: Sixty bovine enamel blocks were divided into six groups ( n = 10): Ice Smirnoff, Skol Beats Senses, Schweppes Vodka Citrus, Jack Daniel’s & Coca‐Cola, Coca‐Cola (positive control), and mineral water (negative control). The beverages were analyzed for pH, titratable acidity (TA), and buffering capacity ( β ). Enamel alterations were assessed using surface microhardness (SMH), while surface roughness (Sa) and enamel surface loss (SL) were measured by optical 3D profilometry. Specimens were immersed in each beverage for 120 min under controlled laboratory conditions with gentle agitation. Data were analyzed using ANOVA and Tukey’s post hoc test ( α = 0.05). Results: All RTD beverages exhibited acidic pH (2.75–3.04). Ice Smirnoff and Skol Beats Senses showed the highest TA and β values. Except for the negative control, all beverages significantly reduced SMH, increased Sa, and presented significant enamel SL ( p < 0.05). The severity of erosive changes was strongly associated with beverage composition, particularly citric acid content and β . Conclusion: RTD alcoholic beverages demonstrated significant erosive potential, promoting enamel surface softening, increased roughness, and SL.

Erosive tooth wear (ETW) compromises enamel integrity. This study investigated the synergistic effects of bioactive silica and fluoride, as well as the independent performance of bioactive silica, in protecting sound enamel and repairing previously eroded enamel under erosive-abrasive challenges. An in vitro laboratory design was adopted using two models: (1) a protective model with sound enamel and (2) a remineralizing model with pre-eroded enamel. Ninety-six bovine enamel blocks were randomly allocated to four dentifrice groups (n=12/group) within two experimental models: RGS/NaF (bioactive silica + 1100 ppm NaF), RGS (bioactive silica without fluoride), NaF (1100 ppm NaF), and NC (fluoride/silica-free). Specimens were exposed to erosive cycling with 0.1% citric acid and simulated toothbrushing treatment for seven days (protective model) or five days (remineralizing model). Surface microhardness, quantitative light-induced fluorescence (QLF), 3D profilometry, and roughness were evaluated. Data were analyzed with ANOVA and Tukey’s post hoc test (p < 0.05). In the protective model, all groups showed microhardness loss, but RGS/NaF maintained the highest hardness values (p < 0.05). In the remineralizing model, all groups demonstrated partial recovery, with RGS/NaF significantly outperforming the others. Bioactive silica alone performed similarly to NaF in several parameters, showing reduced roughness and less structural loss compared with the negative control. The combination of bioactive silica and fluoride provided superior protective and remineralizing effects against erosive-abrasive enamel loss. Bioactive silica alone also exhibited relevant benefits, reinforcing its potential as a viable fluoride-free alternative.

This study aimed to evaluate the effectiveness of bioactive toothpastes in remineralizing eroded enamel surfaces in vitro. Bovine enamel blocks (n = 48) were obtained and classified into untreated, demineralized, and treated areas. Specimens were randomly classified into six groups (n = 8 each): fluoride-free toothpaste (NCT), Colgate Total 12 (PCT), Sensodyne Repair and Protect (SRP), Sensodyne Pronamel (SPE), Regenerador + Sensitive (RGS), and RGS/calcium booster (RCB). The specimens were subjected to erosive pH cycling for 5 days for 4 times/day (90 s) and treated with toothpaste slurries (1:3) for 1 min. The Vickers hardness (50 g/10 s) and percentage surface hardness recovery (%SMHR) were calculated. Furthermore, the topography and roughness (Ra) of the enamel surface were evaluated using a 3D non-contact optical profilometer, along with the tooth surface loss (TSL). Data were statistically analyzed using analysis of variance or Tukey’s test (significance: 5%). The %SMHR of the SRP and NCT groups were significantly lower than those of the other groups (p < 0.05). Ra was higher when the eroded area was treated with SRP and SPE (p < 0.05). Treatment with RGS, PCT, and SPE favored the recovery of the enamel surface compared with the NCT group (p < 0.05). The best TSL results were obtained with treatment with RGS, followed by PCT and SPE (p < 0.05). The RCB group showed statistically equivalent results for surface hardness recovery and TSL (p > 0.05). Conclusively, PCT and RGS toothpastes were more effective in remineralizing the enamel surface.