Background: Currently, the advantages of monochromatic universal composite resin restorative materials have increased their use in dentistry. Accordingly, the optical, surface and mechanical properties of these materials have become more important. This study aimed to evaluate the effect of detox solution on discoloration, surface roughness (SR), and microhardness of different monochromatic universal composite resins (Omnichroma [O], Zenchroma [Z], Vittra [V], and Charisma Diamond One [CDO]). Another aim of this study was to evaluate the monomer conversion degree (DC) of the materials. Methods: A total of 80 specimens were prepared to evaluate the materials (n = 10). After the initial measurements, the specimens were immersed in a red detox solution for 21 days. Statistical data analysis was performed using one-way ANOVA and Tukey’s multiple comparisons. Results: The ∆E values of Z were highest on the 21st day. There was an increase in the SR values of the materials immersed in the detox solution. On the 21st day, top surface microhardness of O was lower than the other materials. There was no statistically significant difference at DC values among material groups. Conclusions: The use of detox solutions for a commercially recommended period of 21 days is suggested. However, this usage period can cause discoloration in restorative materials. Furthermore, especially in the initial one-week period, detox solution may have a negative impact on the microhardness of the materials. In light of all these data, we recommend the cautious use of detox solutions to prevent adverse effects on restorative materials.

The surface properties of composite resin restorative materials are critical for the esthetics and longevity of restorations. This in vitro study evaluated the microhardness change and surface roughness change in four resin composites recommended for anterior restorations after two aging simulations: thermal cycling (10,000 cycles) and one year of water storage. Ten specimens (n = 10) were prepared for each material. After baseline measurements, samples were subjected to one of the aging procedures, and surface properties were reassessed. For microhardness change (∆H), significant differences were observed among materials under both thermal cycling (p = 0.001) and water storage (p = 0.001). Omnichroma–thermal cycling showed a greater decrease than G-ænial Anterior (p = 0.028) and Clearfil Majesty ES-2 (p = 0.001), while Optishade–thermal cycling decreased more than Clearfil Majesty ES-2 (p = 0.015). In water storage, Omnichroma exhibited a greater decrease than Optishade (p = 0.042) and Clearfil Majesty ES-2 (p = 0.001), and G-ænial Anterior decreased more than Clearfil Majesty ES-2 (p = 0.026). Optishade and Clearfil Majesty ES-2 showed significantly greater decreases after thermal cycling than water storage, while Omnichroma and G-ænial Anterior showed no difference. For the change in surface roughness (∆R), significant differences were also found (p = 0.001). In thermal cycling, Optishade exhibited the lowest increase, while G-ænial Anterior showed the highest. In water storage, G-ænial Anterior again had the highest increase, significantly greater than all others (p = 0.001). For all materials, ∆R values were significantly higher after thermal cycling compared with those in water storage (p = 0.001). These results demonstrate that both composite type and aging method influence long-term surface properties. Overall, thermal cycling exerted more detrimental effects than water storage.

ÖZET AMAÇ: Bu çalışmanın amacı, üç farklı üniversal rezin kompozitin (Omnichroma, G-aenial A’chord ve Charisma Diamond One) mikrosertliği, yüzey pürüzlülüğü ve renk değişimi üzerine farklı ağız gargaralarının (Andorex ve Listerine Cool Mint) etkisini araştırmaktır. GEREÇ VE YÖNTEM: Çalışmada kullanılan rezin kompozitlerin her biri için 30 adet olacak şekilde toplam 90 adet örnek hazırlandı, sonrasında yapay tükürükte 24 saat bekletildi. Başlangıç mikrosertlik ölçümleri Vickers sertlik ölçüm cihazı, yüzey pürüzlülük ölçümleri profilometre cihazı ve renk ölçümleri ise spektrofotometre cihazı kullanılarak yapıldı. Sonrasında, hazırlanan örnekler rastgele üç gruba ayrıldı. Grup 1’deki örnekler yapay tükürük içinde, Grup 2’deki örnekler Andorex ağız gargarasında, Grup 3’teki örnekler Listerine Cool Mint ağız gargarası içerisinde 24 saat bekletildi. Takiben, her örneğin mikrosertlik, yüzey pürüzlülüğü ve renk ölçümleri tekrar alındı. Elde edilen veriler tek yönlü varyans analizi ve Tukey çoklu karşılaştırma testi ile istatistiksel olarak p<0.05 anlamlılık düzeyinde analiz edildi. BULGULAR: Tüm üniversal rezin kompozitler ağız gargaraları içerisinde bekletildikten sonra mikrosertlik değerlerinde azalma, yüzey pürüzlülük değerlerinde ise artış olduğu gözlendi (p<0.05). En fazla renk değişimi, Andorex ağız gargarası içerisinde bekletilen gruptaki örneklerden elde edildi. Andorex ağız gargarası içerisinde bekletilen Omnichroma ile hazırlanan örneklerin renk değişimi diğer gruplara göre anlamlı derecede daha yüksek olduğu görüldü (p<0.05). SONUÇ: Üniversal rezin kompozitlerin mikrosertliği, yüzey pürüzlülüğü ve renk değişiminde kullanılan ağız gargaralarının içerikleri rol oynayabilir.

Background: Reliable bonding agents are essential for durable tooth-colored restorations. This study aimed to evaluate the effects of a two-step self-etch adhesive and a universal adhesive (used in self-etch and etch-and-rinse modes) on dentin microshear bond strength and the impact of 1-year simulated thermal aging. Methods: In this study, 60 caries-free human incisors were used. A two-step self-etch adhesive system (SE) (Clearfil SE Bond; Kuraray Noritake Dental, Japan), a universal adhesive in self-etch mode (U-SE) (Clearfil S3 Bond Universal; Kuraray Noritake Dental, Japan), and the same universal adhesive in etch-and-rinse mode (U-ER) were tested. The specimens were randomly divided into six groups ( n = 10 per group): (1) SE, initial measurement without aging (T0); (2) U-SE, initial measurement without aging (T0); (3) U-ER, initial measurement without aging (T0); (4) SE, after artificial aging (T1); (5) U-SE, after artificial aging (T1); and (6) U-ER, after artificial aging (T1). Artificial aging was performed by 10,000 thermal cycles between 5 °C and 55 °C, simulating approximately one year of intraoral conditions. The prepared samples were evaluated using the microshear bond strength test. Non-parametric tests were applied for statistical analysis due to the small sample size and non-normal data distribution, with significance set at p < 0.05. Results: The SE without aging group 1 (15.70 MPa) and SE aged group 4 (11.82 MPa) showed the highest bond strength values, while the U-ER without aging group 3 and aged group 6 consistently presented the lowest (6.58 MPa, 6.33 MPa). After 1-year artificial aging, bond strength significantly decreased in the SE (p<0.05) and U-SE (p0.05). Overall, statistical analysis confirmed significant differences among the adhesive systems and aging conditions (p<0.05). Conclusions: According to the results of this study, when the micro shear bond strengths of dentin adhesive systems were compared, it was found that the SE group showed higher bond strength values than the U-ER and U-SE groups at the beginning and after 1-year aging simulation.

Background: This in vitro study evaluated the effects of two different adhesive application approaches (total-etch and self-etch) and gallic acid (GA) pretreatment on the dentin microshear bond strength (μSBS) of a universal adhesive system. Bond strength was assessed both before thermal aging and following aging procedures simulating approximately 1 and 5 years of clinical service. Materials and Methods: One hundred twenty intact human incisors were allocated to experimental groups according to the adhesive strategy, presence or absence of gallic acid (GA) pretreatment, and thermocycling regimen (0, 10,000, or 50,000 cycles). A universal adhesive system (G-Premio BOND) in combination with a nanohybrid composite resin was applied in accordance with the manufacturers’ instructions. Microshear bond strength (µSBS) was determined using a universal testing device. The obtained data were analyzed by three-way ANOVA and subsequently compared using Tukey’s post hoc test at a significance level of 0.05. Results: In the total-etch approach, pretreatment with gallic acid (GA) resulted in significantly greater µSBS values than those observed in the corresponding untreated specimens under all aging conditions (no thermocycling: 18.53 ± 0.99 vs. 11.33 ± 0.81 MPa; 1-year: 19.86 ± 0.82 vs. 11.60 ± 0.58 MPa; 5-year: 19.04 ± 0.62 vs. 10.28 ± 0.83 MPa; p = 0.001). A comparable trend was noted for the self-etch strategy, where GA application significantly enhanced bond strength compared with the non-treated groups (no thermocycling: 21.70 ± 0.98 vs. 14.19 ± 1.17 MPa; 1-year: 22.60 ± 0.50 vs. 14.94 ± 0.85 MPa; 5-year: 22.32 ± 0.59 vs. 12.94 ± 0.84 MPa; p = 0.001). Across all thermocycling conditions, the self-etch mode consistently produced higher bond strength values than the total-etch mode. Thermal aging did not significantly influence µSBS in the GA-treated groups. In contrast, in the absence of GA pretreatment, thermocycling led to a reduction in bond strength, particularly after the 5-year aging protocol. Conclusions: Gallic acid pretreatment significantly improved dentin bond strength and contributed to the preservation of bond durability after thermal aging. The highest µSBS values were obtained when the self-etch approach was combined with gallic acid (GA) pretreatment, suggesting that GA may serve as a beneficial adjunct for improving the durability and long-term performance of resin–dentin bonds.

The aim of this study was to evaluate the effect of single- and double-layer application of two different universal adhesive systems on the bond strength o