American journal of dentistry最新文献

{"title":"Effects of pediatric syrups on surface roughness and Streptococcus mutans adhesion to restorative materials.","authors":"Mihriban Gökcek Taraç, Meryem Çolak","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the effects of two commonly used pediatric medical syrups on the surface roughness and the adhesion of Streptococcus mutans (S. mutans) to three fluoride-releasing restorative materials: high-viscosity glass-ionomer, polyacid-modified resin composites, and giomer.</p><p><strong>Methods: </strong>The 90 prepared specimens for surface roughness test and 90 specimens for microbial adhesion test were divided into three groups by simple random method for each material (n= 30) and then into three subgroups (n= 10) based on the immersion medium: Augmentin, Calpol, or distilled water. Specimens underwent twice-daily immersion for 2 minutes to simulate routine drug administration followed by storage in artificial saliva (pH 6.8), which was refreshed daily over a 14-day period. Surface roughness and S. mutans adhesion were measured before and after the immersion cycle. Mixed ANOVA was applied to examine the effects of the materials and solution subgroups on surface roughness within the time factor framework. Multiple linear regression was applied to investigate the effects of the materials and solution subgroups on microbial adhesion within the time factor framework. To evaluate the relationship between surface roughness and microbial retention, Spearman's correlation analysis was applied.</p><p><strong>Results: </strong>Augmentin caused a significant increase in surface roughness of polyacid-modified resin composites (P= 0.019), and giomer (P= 0.044), in addition Calpol caused a significant increase for polyacid-modified resin composites (P= 0.0148). High-viscosity glass ionomer had the greatest resistance to surface degradation. Augmentin consistently exhibited the highest microbial adhesion across all material groups except distilled water-GIC group. Calpol (P= 0.002) and distilled water (P< 0.001) also showed a significant increase in microbial adhesion. Giomer was the most resistant material to time-dependent microbial adhesion, whereas glass-ionomer was the most susceptible restorative material. An increase in surface roughness positively correlated with increased microbial adhesion in all material groups.</p><p><strong>Clinical significance: </strong>Exposure to pediatric medical syrups can negatively affect the surface integrity and lead to microbial adhesion to fluoride-releasing restorative materials. These effects vary depending on the material type and the syrup used, highlighting the importance of material selection in pediatric patients exposed to frequent liquid medication intake.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 2","pages":"77-84"},"PeriodicalIF":1.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147759687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface roughness and surface microhardness of bulk-fill and conventional resin composites after erosive-abrasive cycles: A laboratory study.","authors":"Leyla Devletli Ozygit, Guneş Bulut Eyuboglu","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate comparatively the changes in surface roughness and surface microhardness of resin composites applied with traditional incremental layering technique and bulk-fill resin composites after erosive/abrasive applications.</p><p><strong>Methods: </strong>In this laboratory study, three conventional resin composites with different contents: Filtek Z250 (FZ), Filtek Ultimate (FU), Clearfil Majesty Esthetic (CME), and four bulk-fill resin composites: X-tra fil (VXF), Filtek One Bulk Fill (FOB), QuiXfil (QXF), and Tetric N-Ceram Bulk Fill (TNC) were used. While preparing the test specimens, resin composites were applied to 8 mm diameter and 2 mm height round plexiglass molds (n= 15) and polymerized. Each specimen was polished. Then, the baseline surface roughness (R0) and surface microhardness (H0) values of the specimens were measured. Each group had been exposed to erosive/abrasive cycle for 10 days. After the cycle, by measuring the roughness (R1) and microhardness (H1) values of the specimen, the alterations of the surface properties were investigated. After the baseline and erosive/abrasive cycles of the specimens, the surface analyses were performed with scanning electron microscopy. One-way ANOVA test, Tukey's post hoc test, and t-test were used for statistical analysis. Differences at the P< 0.05 level were considered statistically significant.</p><p><strong>Results: </strong>There was no statistically significant difference between the H0 values of the FU, VXF, QXF, and FZ groups, and the H0 values of these groups were higher than the other groups (P< 0.05). After the erosive/abrasive cycle, there was no significant difference in the H1 values of only the FZ and VXF groups (P> 0.05). When the R0 values were examined, there was no significant difference between the FOB, FU, FZ, and TNC groups (P> 0.05), and the R0 values of these groups were statistically lower than the other groups (P< 0.05). A statistically significant increase was observed in the R1 values of all composite materials examined after erosive/abrasive applications (P< 0.05). In the SEM findings, erosive/abrasive applications caused degradation of both the organic matrix and surface properties of inorganic fillers.</p><p><strong>Clinical significance: </strong>According to the results of this laboratory study, erosive and abrasive cycles negatively affected the surface microhardness and roughness of conventional and bulk-fill composites at different rates and varied depending on the structural properties. However, the surface roughness of Filtek Ultimate and Filtek One Bulk Fill, both with nanofill structure, was less affected by combined erosive and abrasive cycles.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 2","pages":"85-94"},"PeriodicalIF":1.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147759700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oral cleansing effect of sugar-free chewing gum with sodium hexametaphosphate and xylitol.","authors":"Minmin Tian, Michael W J Dodds, Li Chen, Yue Sun, Elif Apaydin, De-Yu Hu, Zhi Zhou","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate the effect of sugar-free gum (SFG) with xylitol and sodium hexametaphosphate (SHMP) on oral cleansing by in vitro tests and a human clinical trial.</p><p><strong>Methods: </strong>Hydroxyapatite (HA) discs were pre-treated with SHMP and evaluated for inhibition of stain formation caused by infusion of black tea in vitro. Subsequently, the effect of SFG formulated with different levels of SHMP was determined using a laboratory chewing apparatus to establish effective dosage of SHMP. Stain levels in both tests were assessed by colorimetry to determine L*, a*, b* values. Finally, a 12-week randomized, single blind, parallel arm human clinical study was performed to test effects of xylitol gum with SHMP on clinical indices of stain (Lobene Stain Index) and plaque (Plaque Index). 195 subjects were enrolled, with 181 subjects completing the trial.</p><p><strong>Results: </strong>In vitro pre-treatment of HA discs with SHMP significantly inhibited tea-induced stain. Results from the chewing machine study showed that gums with SHMP significantly inhibited stain formation at 7 and 14 days, with a minimum effective level of 16.5 mg. The clinical study showed that SFG with 50% xylitol and 0.5% SHMP significantly inhibited plaque after 12 weeks compared with baseline and no-gum control (P< 0.05). The test gum also demonstrated a significant reduction of stain formation compared with baseline, no-gum control and commercial gum after 12 weeks (P< 0.05), reducing surface stain by 34% compared with baseline (P< 0.05). It was concluded that sugar-free gum containing xylitol and a low level of SHMP can provide an effective oral cleansing benefit, adjunctive to regular toothbrushing.</p><p><strong>Clinical significance: </strong>In addition to its well-recognized anticariogenic benefit, sugar-free gum formulated with xylitol and a low level of SHMP can also provide an effective oral cleansing benefit by helping control extrinsic tooth stain and plaque accumulation.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 2","pages":"54-60"},"PeriodicalIF":1.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147759694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acute periapical abscesses in patients with inflammatory bowel diseases.","authors":"Ilan Rotstein, Joseph Katz","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the prevalence of acute periapical abscesses (PAs) in patients with inflammatory bowel diseases (IBDs).</p><p><strong>Methods: </strong>Integrated data of hospital patients was used. Data from the corresponding diagnosis codes for Crohn's disease, ulcerative colitis (UC), and PAs were analyzed by querying the appropriate ICD-10 codes in the database.</p><p><strong>Results: </strong>Out of 7,455 Crohn's patients, 121 were affected with acute PAs. Out of 7,352 UC patients, 115 were affected with acute PAs. In both diseases, females were more affected than males, and whites were more affected than African Americans and other ethnicities. The odds ratio (OR) for acute PAs in patients with Crohn's disease was 2.69. The OR for acute PAs in patients with UC was 2.51. The difference in prevalence compared to the total hospital patient population was statistically significant (P< 0.0001). In Crohn's patients, after adjustment for smoking and diabetes co-morbidities, the OR for acute PAs was 1.51 and 2.08, respectively. The difference in prevalence as compared to the total hospital patient population was statistically significant (P< 0.001) and (P< 0.0001), respectively. In UC patients, after adjustment for smoking and diabetes co-morbidities, the OR for acute PAs was 1.44 and 1.46, respectively. The difference in prevalence as compared to the total hospital patient population was statistically significant (P< 0.005).</p><p><strong>Clinical significance: </strong>Clinicians should be cognizant of the possible higher prevalence of periapical abscesses in patients with inflammatory bowel diseases.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"21-24"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whitening toothpastes for coffee and wine stains: Impact on enamel color and roughness.","authors":"Marina P Lopes, Iana Maria C Gonçalves, Julliana A da Silva, Flávio Henrique B Aguiar, Débora A N L Lima","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate, in the laboratory, the effect of whitening toothpastes Colgate Luminous White Lovers Coffee (CLWC) and Wine (CLWW) on dental enamel stained with coffee and red wine, regarding color (ΔEab*, ΔE₀₀, WID) and surface roughness (Ra).</p><p><strong>Methods: </strong>130 samples of bovine incisors were randomly divided into 13 groups (n=10): NC (without staining and brushing); CMP - Colgate Maximum Cavity Protection; CT12 - Colgate Total 12; CLWC - Colgate Luminous White Lovers (Coffee); CLWW - Colgate Luminous White Lovers (Wine); CT12_C - coffee + CT12; CMP_C - coffee + CMP; CLWC_C - coffee + CLWC; NC_C - coffee + distilled water; CT12_W - wine + CT12; CMP_W - wine + CMP; CLWW_W - wine + CLWW and NC_W - wine + distilled water. All analyses were performed twice: Baseline (T0) and 24 hours after brushing protocol (T1). Scanning electron microscopy (SEM) images were obtained. The data were subjected to Shapiro-Wilk normality tests. Kruskal-Wallis and Dunn tests were used for comparisons between groups for color and Ra, and paired Wilcoxon test was used for comparisons between time for Ra. The significance level was 5%.</p><p><strong>Results: </strong>There was a significant difference between groups for ΔEab*, ΔE₀₀, and WID. CLWW_W group showed significantly greater Ra than NC and NC_C at T1. CLWW_W showed a higher erosion of the enamel surface. CLWC and CLWW promoted effective removal of extrinsic staining when exposed to specific staining with coffee and red wine. However, CLWW increased the enamel surface roughness of the samples stained with red wine.</p><p><strong>Clinical significance: </strong>Whitening toothpastes effectively removed coffee- and wine-induced stains, but their abrasive potential, especially after wine exposure, may increase enamel roughness. Clinicians should weigh whitening benefits against possible enamel damage when recommending such products.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"38-46"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of grape seed extract, fluoride and Er,Cr:YSGG laser on dentin tubules.","authors":"Kübra Karaçam, Rahme Zeynep Erdem","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the laboratory effects on human dentin tubules of the single or combined use of grape seed extract (GSE), Er,Cr:YSGG laser and fluoride.</p><p><strong>Methods: </strong>Dentin discs were separated into six groups: Group 1 (control), Group 2 (Er,Cr:YSGG laser), Group 3 (fluoride), Group 4 (fluoride+Er,Cr:YSGG laser), Group 5 (GSE), and Group 6 (GSE+Er,Cr:YSGG laser). The number of closed and semi-closed tubules and the tubule diameters in all the samples were evaluated using SEM analysis.</p><p><strong>Results: </strong>In the comparisons of the number of closed dentin tubules, the combined applications (fluoride+Er,Cr:YSGG laser and GSE+Er,Cr:YSGG laser) were seen to be significantly better than the other groups. The most number of closed dentin tubules were observed in Group 4 (fluoride+Er,Cr:YSGG laser).</p><p><strong>Clinical significance: </strong>The results of this study demonstrated that the incorporation of grape seed extract into dental treatment may offer clinicians an additional option to traditional desensitizing agents, particularly for patients seeking plant-based or minimally processed therapeutic approaches.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"16-20"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of bleaching agents on the surface properties of calcium silicate-based cements.","authors":"Pinar Naiboğlu, Tuğba Koşar","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate surface properties of three calcium silicate-based cements (CSCs) after exposure to bleaching agents.</p><p><strong>Methods: </strong>80 samples of each CSC (Biodentine, MTA Angelus, and MTA Repair HP) were prepared and allocated into four groups (n = 20): three groups were exposed to bleaching agents (sodium perborate, carbamide peroxide, and hydrogen peroxide) three times at 4-day intervals and one control group. The surface microhardness, indentation depth (n=10) and surface roughness (n=10) were measured. The surface morphology and elemental composition was examined using scanning electron microscope-energy dispersive spectroscopy analysis.</p><p><strong>Results: </strong>All bleaching agents induced morphological alterations and affected elemental distribution. Both hydrogen peroxide and carbamide peroxide significantly reduced the microhardness of all CSCs, with hydrogen peroxide causing significantly greater reduction than carbamide peroxide. Both hydrogen peroxide and carbamide peroxide significantly increased indentation depth of all CSCs, with hydrogen peroxide causing a significantly greater increase than carbamide peroxide. All bleaching agents caused a significant increase in surface roughness of all CSCs, with hydrogen peroxide causing the highest increase, followed by carbamide peroxide and sodium perborate. In all groups, Biodentine exhibited lower roughness, lower indentation depth, and higher microhardness compared to MTA Angelus and MTA Repair HP.</p><p><strong>Clinical significance: </strong>The findings suggest that Biodentine exhibited more favorable surface properties compared to MTA Angelus and MTA Repair HP after exposure to bleaching agents, while sodium perborate caused fewer adverse effects than carbamide peroxide and hydrogen peroxide. The choice of CSC and bleaching agent may influence the long-term stability of cervical barriers.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"8-15"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing the accuracy of three digital impression techniques with conventional impression technique for implant-supported fixed full-arch restorations: A prospective clinical study.","authors":"Zhiran Yuan, Zhuoliang Zhou, Shanwei Ge, Yi Yang, Jiahui Zhu, Rouchen Zhang, Lin Li, Ruixia Wang","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To compare the accuracy of stereophotogrammetry (SPG), intraoral scanning (IOS), intraoral scanning with prefabricated splint scan body (IOSS) with the conventional impression technique (CI) for implant-supported fixed full-arch restorations.</p><p><strong>Methods: </strong>Four digital files were obtained for each patient's full arch: a reference scan (laboratory scan of the plaster model obtained by CI) and three test scans (IOS, IOSS, and SPG). The digital files were converted into multi-unit abutment analogs using a digital library. Data were entered into a three-dimensional analysis software to evaluate the distance and angular deviations of the three digital impression techniques relative to the conventional impression technique.</p><p><strong>Results: </strong>A total of 18 edentulous arches were included. Using CI as a reference, SPG exhibited a significant advantage in distance deviation, with significantly lower deviation values compared to IOS and IOSS. Additionally, SPG demonstrated superiority in angular deviation compared to IOS. There were no significant differences between IOS and IOSS in terms of distance or angular deviation. Neither the implant position nor the number of implants significantly affected the distance and angular deviation of SPG and IOSS. However, IOS exhibited increased distance deviation with a higher number of implants, and mandibular implants showed greater location deviation compared to maxillary implants. In all three digital groups, there was no significant correlation between distance and angular deviation with implant system.</p><p><strong>Clinical significance: </strong>Stereophotogrammetry (SPG) demonstrated high accuracy, meeting clinical requirements for edentulous patients and enhancing the digital workflow. Intraoral scanning with prefabricated splint scan body (IOSS) provided better accuracy than intraoral scanning (IOS), meeting clinical demands effectively.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"25-30"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of different whitening toothpastes on resin composite: A laboratory study.","authors":"Ömer Çellik, Tuba Tunç, Rahme Zeynep Erdem","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the laboratory effects of different whitening toothpastes on resin composite with respect to color change and surface roughness.</p><p><strong>Methods: </strong>A total of 50 disc-shaped specimens were prepared from a microhybrid composite (Zenchrom). The samples were randomly divided into five groups for the application of four different whitening toothpastes (Opalescence Whitening Toothpaste, Rocs Sensation Whitening, Luis Bien Active Carbon Toothpaste and Sparkly White Herbal Toothpaste) and one non-whitening toothpaste (Signal Anti-Caries Toothpaste) (n=10). For staining, the samples were kept in coffee solution. Then, all samples were brushed 5,000 strokes with a toothbrush device to simulate a 6-month brushing period. Color measurements of the specimens after staining and brushing were performed using a spectrophotometer. Surface roughness measurements were performed using a mechanical profilometer. The Shapiro-Wilk test, one-way ANOVA and Kruskal-Wallis H test were used for the statistical analysis of the data (P<  0.05).</p><p><strong>Results: </strong>Following the brushing procedures, a significant increase in surface roughness was observed in all the samples (P<  0.05). When the roughness values were compared between the groups after 6 months of brushing, a statistically significant increase in surface roughness was observed with Signal Anti-Caries Toothpaste compared to Luis Bien and Opalescence (P< 0.05). In the evaluations of the color changes, all the toothpastes had whitening effects, but no statistically significant difference was detected between the toothpastes with respect to whitening performance (P> 0.05).</p><p><strong>Clinical significance: </strong>Whitening toothpastes may lighten the color of the resin composite tested, but they can also increase surface roughness. Therefore, dentists should guide patients in selecting appropriate toothpaste products.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"2-7"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of underlying resin composite shade and material thickness on color matching of single-shade resin composites.","authors":"Iris D O Costa, Jade L G Zago, Cecilia P Turssi, Fabiana M G França, Giselle M Marchi, Roberta T Basting, Waldemir F Vieira-Junior","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the influence of the resin-based substrate shade and the single-shade resin composite thickness on color matching ability.</p><p><strong>Methods: </strong>Discs (Ø6 x 2 mm) made from a conventional resin composite (Z350 XT) simulated high- (B1B), medium- (A3B), and low-luminosity (C3B) substrates. Each disc (n=10) received sequential increments of the following single-shade resin composites: Palfique Omnichroma (PO) or Vittra APS Unique (VU), at thicknesses of 0.5, 1 and 2 mm. Color parameters [CIEL*a*b*, Vita Scale (SGU), ΔEab, and ΔE₀₀] were determined for conventional resin composite and post-application measurement of single-shade resin composite thicknesses. Statistical analyses included the Mann-Whitney, Kruskal-Wallis, Dunn, Friedman, or Nemenyi tests (α= 0.05).</p><p><strong>Results: </strong>The ΔEab and ΔE₀₀ values were significantly lower for PO than for VU (P< 0.05). At 1 mm, a decrease in L* values were observed for both resin composites and substrates (P< 0.05). The lowest ΔSGU values were recorded on the high-luminosity substrate (B1B), regardless of the applied thickness (P< 0.05).</p><p><strong>Clinical significance: </strong>Single-shade resin composites did not completely match the resin substrate. Palfique Omnichroma outperformed Vittra APS Unique in all aspects, particularly in showing less overall color change, and especially when applied over high-luminosity resin substrates.</p>","PeriodicalId":7538,"journal":{"name":"American journal of dentistry","volume":"39 1","pages":"31-36"},"PeriodicalIF":1.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147353361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}