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OBJECTIVE: To evaluate the effect of polishing and bleaching on the recovery of lightness, color, whiteness, and relative translucency parameter (RTP) in CAD/CAM materials and changes in these properties when another staining in coffee was conducted after the treatments. MATERIALS AND METHODS: Disks of Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), IPS e.max CAD (EMAX), and Vita Suprinity (VS) were (1) not treated (control), (2) polished with Proxyt or (3) Ceramisté, (4) bleached with Opalescence PF or (5) Whiteness HP Blue, and (6) air polished with Clinpro Prophy Powder. CIE L*a*b* color coordinates were registered at baseline (R0), after staining with coffee for 30 min daily for 36.5 days and treatment (R1), and after another staining (R2). Differences (R1-R0 and R2-R0) in lightness (ΔL00), color (ΔE00), RTP (ΔRTP00), and whiteness (ΔWID) were evaluated by mixed repeated measures ANOVA and 95% confidence intervals (α = 0.05) and interpreted in function of their respective 50:50% PT and AT thresholds. Topography was evaluated by scanning electron microscopy (SEM). RESULTS: In LU, Opalescence PF and Proxyt decreased Δ L 00 R 1 - R 0 $$ {\Delta L}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , Δ E 00 R 1 - R 0 $$ {\Delta E}_{00\left({R}_1\hbox{--} {\mathrm{R}}_0\right)} $$ , and ΔWI D R 1 - R 0 $$ {\Delta \mathrm{WI}}_{\mathrm{D}\left({R}_1\hbox{--} {R}_0\right)} $$ and showed lower Δ L 00 R 2 - R 0 $$ {\Delta L}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ , Δ E 00 R 2 - R 0 $$ {\Delta E}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ , and ΔWI D R 2 - R 0 $$ {\Delta \mathrm{WI}}_{\mathrm{D}\left({R}_2\hbox{--} {R}_0\right)} $$ . In VE, all treatments decreased Δ L 00 R 1 - R 0 $$ {\Delta L}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , Δ E 00 R 1 - R 0 $$ {\Delta E}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , and ΔWI D R 1 - R 0 $$ {\Delta \mathrm{WI}}_{\mathrm{D}\left({R}_1\hbox{--} {R}_0\right)} $$ , whereas Δ L 00 R 2 - R 0 $$ {\Delta L}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ , Δ E 00 R 2 - R 0 $$ {\Delta E}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ , and ΔWI D R 2 - R 0 $$ {\Delta \mathrm{WI}}_{\mathrm{D}\left({R}_2\hbox{--} {R}_0\right)} $$ were lower in Opalescence PF than in the control group. In both moments, ΔE00 and ΔWID in EMP (also ΔL00) and EMAX were higher in Opalescence PF than in the control group, from which the other treatments did not differ in R1-R0. In EMP, Δ E 00 R 2 - R 0 $$ {\Delta E}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ in Whiteness HP Blue (also Δ L 00 R 2 - R 0 $$ {\Delta L}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ ) and Proxyt were also higher in comparison to the control group and in VS, Ceramisté decreased Δ L 00 R 1 - R 0 $$ {\Delta L}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , Δ E 00 R 1 - R 0 $$ {\Delta E}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , and Δ R T P 00 R 1 - R 0 $$ \varDelta RT{P}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ , whereas Opalescence PF increased ΔRTP 00 R 1 - R 0 $$ {\Delta \mathrm{RTP}}_{00\left({R}_1\hbox{--} {R}_0\right)} $$ . Δ E 00 R 2 - R 0 $$ {\Delta E}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ of Ceramisté and ΔWI D R 2 - R 0 $$ {\Delta \mathrm{WI}}_{\mathrm{D}\left({R}_2\hbox{--} {R}_0\right)} $$ and Δ R T P 00 R 2 - R 0 $$ \varDelta RT{P}_{00\left({R}_2\hbox{--} {R}_0\right)} $$ of Proxyt were lower than those of the control group. CONCLUSIONS: The most suitable treatment to recover the lightness, color, whiteness, and RTP without changing these properties after another coffee exposure is material-dependent. CLINICAL SIGNIFICANCE: Although the effectiveness of the treatment was material-dependent, Proxyt was the only treatment that promoted clinically acceptable changes for both LU and VE, while for purely ceramic materials, this condition was observed with Ceramisté and Clinpro Prophy Powder.

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OBJECTIVE: Evaluate the color and translucency of a nanoceramic resin subjected to hygiene practices and immersion in coffee over time. MATERIALS AND METHODS: Specimens (n = 80, HT and LT, 0.5-mm thick) of a nanoceramic resin were obtained and were divided in groups according to the simulated oral hygiene: no intervention (NT), brushing with an electric brush and water (BN), brushing with an electric brush and toothpaste for 10 s (BT), and immersion in mouthwash for 30 s (MW). Oral hygiene practices were repeated after staining in coffee solution for 15, 48, 336, 1440, 8640, and 35,040 min. Spectral wavelengths were recorded with a spectrophotometer at each time. ∆E00, ∆L', ∆C', ∆H', and TP00 were calculated by CIEDE2000 and were evaluated by 2-way ANOVA, repeated measures ANOVA, and Tukey's HSD test (α = 0.05). RESULTS: ANOVA showed significance among factors for ΔE00 (p < 0.05), with higher ΔE00 for NT-HT (11.7) and NT-LT (11.2). After T6 (2-year simulation), the lowest values were found for BT-HT (5.3) and BT-LT (4.9). All groups showed a reduction in lightness and translucency and increased chroma and hue. However, the smallest variations were found in the BT groups (p < 0.05). CONCLUSIONS: Brushing with toothpaste effectively minimized the color change of NCRs caused by coffee staining. CLINICAL SIGNIFICANCE: Oral hygiene practices, such as brushing with toothpaste, might be important to minimize staining of nanoceramic resin restorations, especially in patients who frequently consume coffee.

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More than three decades have passed since the publication of Lamendin et al.'s proposal in 1992. Over this time, numerous investigations have been conducted to assess the applicability of the technique in different populations with acceptable results in terms of estimation errors. The proposal by Lamendin and colleagues remains relevant today, and has made a significant contribution to adult age-at-death estimation due to its simplicity, repeatability, replicability, and high performance. Indeed, significant progress towards systematizing and strengthening the procedure has been reported in the published literature. One noteworthy advancement is the development of an international database that supports the use of Bayesian statistics for age-at-death estimation. This resource plays a crucial role in standardizing the methodology and improving the reliability for obtaining more reliable results on a global scale. The aim of this study is to investigate the historical evolution of the technique, to assess the accuracy of the results obtained by different analytic procedures, and to explore its impact in forensic applications through a systematic analysis of the specialized literature on this field. The current state of research indicates that this type of methodological research is an ongoing process, far from being completed. Many questions and challenges that require further attention to address effectively these issues remain unanswered, such as the development of non-linear regressions and probabilistic approaches, the deepening of procedures that improve global approximations, and the intensification of research focused on achieving more accurate estimations among individuals over 70 years-old. However, studies generally agree that the Lamendin technique works well for individuals between the ages of 30-60 years. It is still in force today, although the method has been significantly perfected. Despite the degree of research development in this area, further efforts are needed to improve the understanding and performance of these kinds of procedures. This will ultimately lead to an improvement in the accuracy and reliability of forensic investigation results worldwide.

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To evaluate color differences (ΔE00) and translucency parameters (TP) from mono, bi, and trilayer resin composite veneers using different opacities and shades of resin composite over lighter and darker simulated tooth-colored substrates. Mono, bi, and trilayer veneers (1.5 mm) (n = 12) were made using two shades (A1 and A2) and three opacities (enamel, body, and dentin) of resin composite over simulated lighter (A1) and darker (C4, and C4+) tooth-colored substrates. CIEDE2000 formula was used to calculate ΔE00 considering simulated tooth-colored substrate versus opacities in distinct mono, bi, and trilayer combinations of resin composite over the simulated tooth-colored substrate. The TP was calculated using color coordinates measured over standard white and black backgrounds. Differences in ΔE00 and TP values were calculated with a Three-way Analysis of Variance followed by Tukey's post-hoc test. A1E and A1B monolayer veneers showed similar TP values. Significantly higher ΔE00 values were observed over darker (C4 and C4+), and lower over lighter (A1) simulated tooth-colored substrate. Bilayer and trilayer veneers using dentin opacity provided similar ΔE00 values over the darker tooth-colored substrate. Distinct shades and opacities of resin composite layer combinations over lighter and darker tooth-colored substrates significantly affected TP and ΔE00 values. A1 shade and dentin opacity of monolayer resin composite veneers yielded higher ΔE00 values over darker tooth-colored substrates.

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OBJECTIVE: To evaluate the optical properties and the relative translucency parameter of Ceramill ZI White (3Y-TZP) and Ceramill Zolid FX White (5Y-PSZ) zirconia ceramic systems and compare them with those of the bovine dentin and enamel/dentin structures. MATERIALS AND METHODS: 3Y-TZP and 5Y-PSZ zirconia ceramic systems were evaluated. A 0.5-mm-thick 3Y-TZP (3Y-NC.5), 0.5-mm-thick (5Y-NC.5), and 1.4-mm-thick (5Y-C.14) were used. A 0.5-mm-thick dentin specimens and 1.4-mm-thick enamel/dentin specimens (n = 5) were obtained from anterior bovine maxillary teeth. Scattering, absorption, transmittance, and albedo coefficient were calculated using Kubelka-Munk's model. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney tests (p < 0.001), and goodness-of-fit coefficient (GFC). Relative translucency parameter differences were evaluated using translucency thresholds. RESULTS: Reflectance, scattering, absorption, and transmittance properties were wavelength dependent. Good matches (GFC ≥ 0.999) in spectral reflectance were observed between 0.5-mm-thick dentin and 1.4-mm-thick enamel/dentin, and 3Y-NC.5 and 5Y-NC.5. Scattering was the main optical extinction process during light interaction with zirconia and dental structures, as indicated by albedo coefficient. Translucency differences were acceptable only for 3Y-NC.5 and the dentin structure, and 5Y-C.14 and the enamel/dentin structure. CONCLUSIONS: Optical properties of 3Y-TZP and 5Y-PSZ dental zirconia differed from each other and from bovine dental structures. Nevertheless, 3Y-TZP showed similar relative translucency parameter to bovine dentin. CLINICAL SIGNIFICANCE: To achieve the best esthetic results in restorative dentistry, it is crucial for clinicians to know about the optical properties of 3Y-TZP and 5Y-PSZ and to be able to compare these properties with those of dental structures.

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Resumen Objetivo: Describir y analizar los hallazgos ecográficos en 97 fetos portadores de síndrome de Down (SD) confirmado. Método: Se incluyeron todas las gestantes con diagnóstico prenatal de SD de nuestro centro, realizado por cariograma o reacción en cadena de la polimerasa cuantitativa fluorescente para aneuploidía. Se analizaron los informes genéticos y ecográficos, y se realizó un seguimiento posnatal. Resultados: De los 97 casos de SD, el 73% de los diagnósticos fueron entre las 11 y 14 semanas. El promedio de edad de las madres fue de 35,7 años. El 83% de los fetos con SD, evaluados a las 11-14 semanas, tuvieron una translucencia nucal ≥ 3,5 mm. Del total de los casos analizados, el 33% fueron portadores de una cardiopatía congénita, correspondiendo el 58% de estas a defectos mayores, principalmente anomalías del tabique auriculoventricular. Un 7,6% de los casos terminaron como mortinato, principalmente durante el tercer trimestre. Conclusiones: El ultrasonido es una herramienta muy sensible para la sospecha prenatal de SD y la detección de sus anomalías asociadas. Consideramos que la información aportada será útil para programar estrategias de pesquisa, organizar el control perinatal y precisar el consejo a los padres de fetos portadores de esta condición.

Abstract Objective: To describe and analyze the ultrasound findings in 97 fetuses with confirmed Down syndrome (DS). Method: All pregnant women with prenatal diagnosis of DS in our center, performed by karyotype or quantitative fluorescent polymerase chain reaction for aneuploidy, were included. Genetic and ultrasound reports were analyzed, as well as postnatal follow-up. Results: Of the 97 cases of DS, 73% of the diagnoses were between 11-14 weeks. The average age of the mothers was 35.7 years. 83% of our fetuses with DS, evaluated between 11-14 weeks, had a nuchal translucency ≥ 3.5 mm. Of the total of the fetuses analyzed, 33% were carriers of congenital heart disease, 58% of these correspond to a major defect, mainly anomalies of the atrioventricular septum. 7.6% of cases ended as stillbirth, mainly during the third trimester. Conclusions: Ultrasound is a very sensitive tool for prenatal suspicion of DS and the detection of its associated abnormalities. We believe that the information provided will be useful to program screening strategies, organize perinatal control and to counselling parents of fetuses carrying this condition.

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Objetivo. Evaluar la asociación del higroma quístico retronucal (HQR) y anomalías cromosómicas fetales. Métodos. Estudio observacional retrospectivo de 323 fetos del primer trimestre con riesgo para anomalías cromosómicas diagnosticados por ecografía entre las 11 y 13,6 semanas. Resultados. De 323 fetos con riesgo para anomalías cromosómicas, se encontró 132 casos de anomalías cromosómicas (40,9%). Se identificaron 145 casos de HQR; en 64 (56,6%) se realizó biopsia de vellosidades coriales y en 81 (43,5%) amniocentesis, hallándose cariotipo anómalo en 82 (56,6%). De 88 fetos con HQR aislado, 33 casos (37,5%) tuvieron alguna anomalía cromosómica; en 58 fetos con HQR asociado a otros hallazgos anormales, se encontró que en 43 fetos (74,1%) hubo anomalías cromosómicas, y de ellos 24 (41,4%) tenían onda de flujo (OVF) anormal del ductus venoso, 17 (29,3%) tenían edema generalizado, 8 casos (13,8%) con cardiopatía, 7 (12,1%) ausencia del hueso nasal. Los valores predictivos del HQR fueron: sensibilidad (S) 62,1%, especificidad (E) 67%, valor predictivo positivo (VPP) 56,6%, valor predictivo negativo (VPN) 71,9%, p<0,001, OR: 3,3. El HQR asociado a otros hallazgos anormales, tuvo los siguientes valores predictivos: S 52,4%, E 76,2%, VPP 76,2%, OR: 3,5, LR+: 2,2, p<0,000. El edema generalizado y el ductus venoso anormal tuvieron los valores predictivos más altos: VPP 88,2% y 83,3%, respectivamente. Las anomalías cromosómicas encontradas con mayor frecuencia fueron: T21 (53,7%), monosomía X (18,3%), T18 (15,9%), T13 (6,1%). Conclusiones. El higroma quístico retronucal es un marcador de riesgo con alto valor predictivo para anomalías cromosómicas, siendo mayor cuando está asociado a otros hallazgos ecográficos anormales. La identificación ecográfica del HQR en el tamizaje prenatal del primer trimestre debería ser indicación para recomendar una prueba diagnóstica para anomalías cromosómicas.

Objective: To evaluate the association of retronucal cystic hygroma (RCH) and fetal chromosomal abnormalities. Methods: Retrospective observational study of 323 first trimester fetuses at risk for chromosomal abnormalities diagnosed by ultrasound between 11 and 13.6 weeks. Results: Of 323 fetuses at risk for chromosomal abnormalities, 132 cases of chromosomal abnormalities were found (40.9%). A total of 145 cases of RCH were identified; chorionic villus biopsy was performed in 64 (56.6%) and amniocentesis in 81 (43.5%); an abnormal karyotype was found in 82 (56.6%). Of 88 fetuses with isolated RCH, 33 (37.5%) had some chromosomal abnormality. In 58 fetuses with RCH associated with other abnormal findings, chromosomal abnormalities were found in 43 fetuses (74.1%) and of these 24 (41.4%) had abnormal ductus venosus flow wave (DVF), 17 (29.3%) had generalized edema, 8 cases (13.8%) with cardiopathy, 7 (12,1%) with absent nasal bone. The predictive values of RCH were sensitivity (S) 62.1%, specificity (Sp) 67%, positive predictive value (PPV) 56.6%, negative predictive value (NPV) 71.9%, p<0.001, OR: 3.3. RCH associated with other abnormal findings were S 52.4%, Sp 76.2%, PPV 76.2%, OR: 3.5, LR+: 2.2, p<0.000. Generalized edema and abnormal ductus venosus had the highest predictive values: PPV 88.2% and 83.3%, respectively. The most frequently found chromosomal abnormalities were T21 (53.7%), monosomy X (18.3%), T18 (15.9%), T13 (6.1%). Conclusions: Retronucal cystic hygroma is a risk marker with high predictive value for chromosomal abnormalities, being higher when associated with other abnormal ultrasound findings. Ultrasonographic identification of RCH in first trimester prenatal screening should be an indication to recommend diagnostic testing for chromosomal abnormalities.

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Objetivo: O objetivo deste estudo é avaliar o efeito de múltiplas queimas e envelhecimento na cor e na translucidez da vitrocerâmica de dissilicato de lítio reprensada (IPS e.max press). Material e Métodos: Um total de 42 discos de dissilicato de lítio (15 mm x 1 mm) foram fabricados usando a técnica de prensa térmica seguindo as instruções dos fabricantes. Eles foram divididos em três grupos de acordo com o número de ciclos de prensagem (n=14): Grupo P1 (pressionado uma vez), Grupo P2 (pressionado duas vezes) e Grupo P3 (pressionado três vezes). Cada grupo foi subdividido em dois subgrupos de acordo com o número de ciclos de queima (n=7): Subgrupo (F2): 2 ciclos de queima, Subgrupo (F4): 4 ciclos de queima. Em seguida, todos os corpos de prova foram submetidos à termociclagem. Os parâmetros de cor e translucidez (TP) foram avaliados por espectrofotômetro; após a prensagem, queima (ΔE1: diferença de cor entre prensagem e queima) e envelhecimento (ΔE2: diferença de cor entre prensagem e envelhecimento). Resultados:ΔE1 para o subgrupo F2 (3,38) apresentou menor valor estatisticamente significante do que ΔE1 para o subgrupo F4 (3,94). Após o envelhecimento, o grupo P3 apresentou o maior ΔE2 estatisticamente significante (6,41). Um ΔE2 estatisticamente inferior foi encontrado no grupo P2 (5,55). O grupo P1 apresentou o menor ΔE2 estatisticamente significante (4,28). O TP para o subgrupo F2 (18,27) apresentou valor superior ao subgrupo F4 (17,78). Houve uma diminuição estatisticamente significante no TP após o envelhecimento para todos os grupos testados. Conclusão: O aumento do número de ciclos de queima e de envelhecimento afetaram a cor e a translucidez do dissilicato de lítio reprensado. (AU)

Objective: The aim of this study is to evaluate the effect of multiple firings and aging on color and translucency of repressed lithium disilicate glass ceramic (IPS e.max press). Material and Methods: A total of 42 lithium disilicate discs (15 mm x 1 mm) were fabricated using heat press technique following the manufacturers' instructions. They were divided into three groups according to the number of pressing cycles (n=14): Group P1 (pressed once), Group P2 (pressed twice) and Group P3 (pressed thrice). Each group was subdivided into two subgroups according to the number of firing cycles (n=7): Subgroup (F2): 2 firing cycles, Subgroup (F4): 4 firing cycles. Then all specimens were subjected to thermocycling. Color and translucency parameter (TP) were evaluated by spectrophotometer; after pressing, firing (ΔE1: color difference between pressing and firing) and aging (ΔE2: color difference between pressing and aging). Results:ΔE1 for subgroup F2 (3.38) showed statistically significant lower value than ΔE1 for subgroup F4 (3.94). After aging, group P3 showed the statistically significant highest ΔE2 (6.41). A statistically significant lower ΔE2 was found with group P2 (5.55). Group P1 showed the statistically significant lowest ΔE2 (4.28). TP for subgroup F2 (18.27) showed higher value than subgroup F4 (17.78). There was a statistically significant decrease in TP after aging for all tested groups. Conclusion: Increasing the number of firing cycles and aging affected color and translucency of repressed lithium disilicate. (AU)

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The aim of this study was to measure the nuchal translucency (NT) of canine fetuses to establish reference values ​​for healthy gestational processes and to verify its effectiveness in the diagnosis of congenital abnormalities. On day 34 of gestation, the NT of three fetuses from each of the 26 English bulldog female dogs was measured. The first fetus was the one located immediately cranial to the bladder, the second was selected from the left side of the abdomen, and the third from the right side. The reference values for healthy animals were offset using descriptive statistics. The diagnostic ability of the test to identify fetal malformations was studied using receiver operating characteristic curve analysis. Of the 26 litters, only 18 had healthy fetuses, 4 had fetuses with anasarca, 3 had fetuses with abdominal wall defects, and 1 had both types of abnormalities. The NT was higher in canine fetuses that presented anasarca in the litter than in normal litters (1.8 ± 0.77 mm vs. 1.4 ± 0.48 mm; P = 0.0249), with a cut-off value of NT > 1.45 mm (sensitivity = 61.54%, specificity = 70.18%). NT greater than 1.45 mm seems to be a diagnostic tool for the identification of anasarca during gestation of bulldogs. Considering the unprecedented use of this parameter in canine species and the limitations found during the study, further studies will be needed in order to use it on clinical practice.

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In forensic science, the information that teeth provide to the age estimation process is very important. In adults, one of the most widely used indicators of skeletal age is the Root Dentin Translucency (RDT), mainly through the Lamendin technique, which is used in various Latin American contexts. Recently, Parra et al. (2020) have developed a Bayesian regression model using the Lamendin technique to establish standardized criteria for estimating age-at-death in adults in various forensic contexts. In this study, we evaluate the applicability of this proposal together with the proposal by Lamendin et al. (1992) and Prince and Ubelaker (2002) in Latin American contexts. A sample of single-rooted teeth belonging to 805 individuals from six Latin American countries was used. The results of the three proposals considered were analyzed taking into account factors such as age, sex, origin, and the tooth surface on which the variables were surveyed. Of the factors that would affect the estimates, it was found that the age of the individuals had the greatest influence. However, it was confirmed that the sex and surface of the teeth on which the measurements were taken did not influence the final result. On the other hand, as we expected, the application of the analyzed proposals would also be possible in other forensic contexts, as shown by the results obtained according to the origin. This research expands the FIDB with more information on Latino contexts.

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OBJECTIVE: To conduct a systematic review on the masking ability of discolored substrates, analyzing the capacity and quality of the response produced by the different methodologies and techniques applied to overcome this clinical challenge. MATERIALS AND METHODS: The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The electronic search was conducted in MEDLINE/PubMed, Scopus and Web of Science databases, without date restriction. In vitro studies, written in English, applying different methodologies to evaluate masking ability were included. The variables of interest were: type, color and thickness of the restorative and/or cement material; use of pigments in the restorative material and/or cement; color of the substrate; and background color used for the evaluations. RESULTS: Database search retrieved 307 eligible papers with a final inclusion of 47 published papers. Approximately 98% of the studies used ΔE, 36% used TP, and only 6% used CR to evaluate the masking ability of restorative materials. CONCLUSIONS: The most appropriate methodology to evaluate the masking ability is using color difference equations (ΔE) associated with the perceptibility and acceptability thresholds. CLINICAL SIGNIFICANCE: As different methodologies have been used to evaluate the masking ability of esthetic restorative materials on colored substrates, there is an urgent need to reach a consensus and propose a method, which is suggested by the present systematic review.

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OBJECTIVE: To evaluate color differences (ΔE) of different fabrication steps performed on a feldspathic ceramic and relative translucency parameter (RTP) after glazing; and to evaluate their effects on the color parameters: L*, a* and b*. MATERIAL AND METHODS: Computer-aided design/computer-aided manufacturing (CAD-CAM) feldspathic maxillary right central incisor ceramic crowns (Cerec Blocs; 1.4 mm thickness) were fabricated through scanning a model preparation and milling. A total of 20 specimens were used and different parameters were compared with each other for color difference (ΔE): original block, milling, polishing, glazing and try-in cements; RTP was measured after glazing. Color parameters (L*, a*, and b*) were evaluated after each step with a spectrophotometer (Vita Easyshade V) and compared using the CIEDE2000 formula. Statistical analyses were done using one-way ANOVA and post-hoc tests. RESULTS: The highest ΔE value was observed for Original versus Milling group (4.73) and the lowest for Polishing versus Glazing (0.49). RTP after glazing presented a value of 12.01. L*, a*, and b* parameters were different among groups. Milling group was the one that presented more differences compared to the Original block regarding L*, a*, and b* parameters. CONCLUSIONS: Different fabrication steps resulted in perceptible color differences within themselves, and L*, a*, and b* parameters changed according to each step. All milling specimens presented unacceptable color differences when compared to the other steps, and milling specimens showed all color parameters (L*, a*, and b*) statistically different compared to the Original block. A high RTP value was observed, demonstrating that, at 1.4 mm thickness, the feldspathic ceramic presented high translucency, showing that opacification of substrate might be necessary. CLINICAL SIGNIFICANCE: Different fabrication steps can greatly affect the optical properties of the feldspathic ceramic restoration studied and cause a relevant impact when compared to the ceramic block itself. Crowns evaluated right after milling presented the highest color differences. In order to obtain optical properties as close as possible to the original feldspathic ceramic block, either polishing or polishing and glazing needs to be performed.

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OBJECTIVE: Continuous efforts have been made to hasten the zirconia densification process without compromising properties. This study evaluated the long-term structural durability of microwave speed-sintered zirconia (MWZ) relative to a conventionally sintered zirconia (CZ). METHODS: As-machined dental 3Y-TZP discs (Ø12 × 1.2 mm) were speed sintered at 1450 °C for 15 min using an industrial microwave oven, while conventional sintering was conducted in a standard dental furnace at 1530 °C for 2 h. Both were followed by natural cooling. The total sintering time was 105 min for MWZ and 600 min for CZ. Groups were compared regarding density, grain size, phase composition, and fracture resistance. Structural durability was investigated employing two fatigue protocols, step-stress and dynamic fatigue. RESULTS: Compared to CZ, MWZ exhibited a slightly lower density (MWZ = 5.98 g/cm3, CZ = 6.03 g/cm3), but significantly smaller grain sizes (MWZ = 0.53 ± 0.09 µm, CZ = 0.89 ± 0.10 µm), lower cubic-zirconia contents (MWZ = 15.3%, CZ = 22.7%), and poorer translucency properties (TP) (MWZ = 13 ± 1, CZ = 29 ± 0.8). However, the two materials showed similar flexural strength (MWZ = 978 ± 112 MPa, CZ = 1044 ± 161 MPa). Additionally, step-stress testing failed to capture the fatigue effect in 3Y-TZP, whereas dynamic fatigue revealed structural degradation due to moisture-assisted slow-crack-growth (SCG). Finally, MWZ possessed a slightly higher Weibull modulus (MWZ = 7.9, CZ = 6.7) but similar resistance to SCG (MWZ = 27.5, CZ = 24.1) relative to CZ. SIGNIFICANCE: Dental 3Y-TZP with similar structural durability can be fabricated six-times faster by microwave than conventional sintering.

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Resumen La odontología forense representa una de las disciplinas más útilesen la identificación de seres humanos, los dientes también puedenbrindar entre otras características la edad aproximada de una persona. A lo largo de la historia se han desarrollado diferentes métodos de estimación de edad dentro de los cuáles el método de Lamendin(translucidez radicular) resulta sencillo y bastante precisosin la necesidad de equipo especializado para su realización. Como cualquier método diagnóstico presenta limitaciones, puede ser utilizado en adultos después de los 20 años en dientes unirradiculares sin caries, presentando mayor fiabilidad y precisión, cuando el rango de edad se mantiene entre 40 y 70 años. Sin embargo, el mismo no toma en consideración el sexo, ni la raza, por lo que esto puede representar una limitación considerable; aunado a lo anterior en Costa Rica hasta hoy no existen estudios que permitan corroborar la efectividad del método Lamendin en la población.

Abstract Forensic dentistry represents one of the most useful disciplines in the identification of human beings, teeth can also provide, among other characteristics, the approximate age of a person. Throughout history, different age estimation methods have been developed, among which the Lamendin method (root translucency) is simple and quite accurate without the need for specialized equipment to perform it.As any diagnostic method has limitations, it can be used in adults after the age of 20 in single-rooted teeth without caries, presenting greater reliability and precision, when the age range remains between 40 and 70 years. However, it does not take gender or race into consideration, so this can represent a considerable limitation; In addition to the above, in Costa Rica, to date, there are no studies that allow corroborating the effectiveness of the Lamendin method in the population.

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OBJECTIVE: To evaluate the translucency parameter (TP) and contrast ratio (CR) of different conventional restorative glass-ionomer cements (GICs). MATERIALS AND METHODS: Eighteen brands of GICs were evaluated. Five disks of each material were made following ISO 9917-1. The luminous reflectance and Central Bureau of the International Commission on Illumination parameters of disks were evaluated using a colorimeter, against backings of white and black, to obtain the translucent parameter and contrast ratio of different brands of glass-ionomer cements. The correlation between translucency parameter and contrast ratio was assessed with the Pearson correlation test. The translucent and contrast ratio parameters values were submitted to the one-way ANOVA and Tukey test for multiple comparisons (p < 0.05). RESULTS: There was a strong inverse relationship between CR and TP (r2  = 0.94, p < 0.001). The contrast ratio decreased as translucency increased. There were significant differences in TP and CR among brands (p < 0.001). CONLUSIONS: GICs exhibit different translucency and contrast ratio behavior. Some brands of GICs presented very low TP and this condition would be unacceptable for areas with esthetic demands. In addition, TP and CR showed a strong linear relationship. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the knowledge of the translucency and CR of different conventional restorative GICs is important in order to guide clinicians in the selection of restorative GICs for anterior teeth.

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OBJECTIVE: To evaluate color, lightness, chroma, hue, and translucency adjustment potential of resin composites using CIEDE2000 color difference formula. METHODS: Three resin composites (Filtek Universal, Harmonize, and Omnichroma) were tested. Two types of specimens were prepared: an outer base shade with an inner hole filled with test shades and single-composite specimens of all shades. Spectrorradiometric reflectances measurements and subsequent CIELAB color coordinates and translucency parameter (TP) were performed. Color (CAP00 ), lightness, chroma, hue, and translucency (TAP00 ) adjustment potential using CIEDE2000 color difference were computed. Color and transparency differences among composite materials and shades were statistically tested (P < 0.05). RESULTS: Positive CAP00 and TAP00 values were found for majority of tested materials. CAP00 values ranged from -0.14 to 0.89, with the highest values found for Omnichroma (>0.75 in all cases). TAP00 values ranged from -0.06 to 0.86 with significant translucency differences among dual and single specimens. Omnichroma exhibited the highest adjustment potential for all color dimensions studied. CONCLUSIONS: Lightness, hue, chroma, and translucency adjustment potential have been introduced using CIEDE2000 color difference formula, and have shown their usefulness to evaluate blending effect in dentistry. Color coordinates and translucency adjustment potential were dependent on dental material. Omnichroma exhibited the most pronounced blending effect. CLINICAL SIGNIFICANCE: Resin composites with increased color and translucency adjustment may simplify shade selection, making this process easier and less time consuming. Furthermore, these materials might facilitate challenging and complex color matching situations.

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Objective: To compare the color stability and translucency of aged and unaged experimental zirconia reinforced rice husk nanohybrid composite resin (Zr-Hybrid) with a commercialized nanofilled and a microhybrid composite resin after immersion in four different infusion media. Material and Methods: Three groups of standardized disc-shaped composite resin with 80 samples per group were prepared as follow: Group 1 (Filtek-Z350-XT), Group 2 (Zmack-Comp), and Group 3 (Zr-Hybrid). Each group was further subdivided into aged (n=40) and unaged (n=40) groups. Initial color measurements were taken using a digital spectrophotometer based on CIE L*a*b* color system. Samples in aged subgroup were subjected to 2500 thermal cycles. Subsequently, all samples were immersed in four different types of infusion media (n=10): T1 - Distilled water, T2 - Soft drink, T3 - Tea and T4 - Coffee. After 15 days, color measurements of all samples were measured again. Data were analyzed using two-way ANOVA followed by Bonferroni and paired sample t-tests with a significance level set at P=0.05. Results: Unaged Zr-Hybrid showed comparable color change to Zmack-Comp and Filtek-Z350-XT (P=0.181), but aged Zr-Hybrid demonstrated the lowest color change (P<0.001). Zr-Hybrid exhibited the lowest translucency value (P<0.001), but no significant color and translucency changes (P=0.051 and P=0.069, respectively) were observed between unaged and aged Zr-Hybrid. Soft drink had the greatest effect (P<0.001) on color change, while coffee showed the greatest effect (P<0.001) on translucency. Conclusion: Although Zr-Hybrid showed greater opacity, it still retained its color stability and translucency after accelerated aging compared to commercialized microhybrid and nanofilled composite resins. All infusion media caused discoloration and affected the composite resins' translucency. (AU)

Objetivo: Comparar a estabilidade de cor e translucidez de uma resina composta nanohíbrida de casca de arroz reforçada com zircônia experimental envelhecida e não envelhecida (Zr-Hybrid) com uma resina composta comercial nanoparticulada e microhíbrida após a imersão em quatro meios de infusão diferentes. Material e Métodos: Três grupos de resina composta em forma de disco padronizado com 80 amostras por grupo foram preparados da seguinte forma: Grupo 1 (Filtek-Z350-XT), Grupo 2 (Zmack-Comp) e Grupo 3 (Zr-Hybrid). Cada grupo foi subdividido em grupos de envelhecimento (n = 40) e não envelhecimento (n = 40). As medições iniciais de cor foram feitas usando um espectrofotômetro digital baseado no sistema de cores CIE L * a * b *. As amostras do subgrupo envelhecido foram submetidas a 2500 ciclos térmicos. Posteriormente, todas as amostras foram imersas em quatro tipos diferentes de meios de infusão (n = 10): T1 - Água destilada, T2 - Refrigerante,T3 - Chá e T4 - Café. Após 15 dias, as medições de cor de todas as amostras foram medidas novamente. Os dados foram analisados usando ANOVA dois fatores seguido por Bonferroni e testes t pareados com nível de significância estabelecido em P = 0,05. Resultados: O grupo Zr-Hybrid não envelhecido mostrou uma mudança de cor comparável a Zmack-Comp e Filtek-Z350-XT (P = 0,181), mas o grupo Zr-Hybrid envelhecido demonstrou a menor mudança de cor (P <0,001). Zr-Hybrid exibiu o menor valor de translucidez (P <0,001), mas nenhuma mudança significativa de cor e translucidez (P = 0,051 e P = 0,069, respectivamente) foram observadas entre Zr-Hybrid não envelhecido e envelhecido. O refrigerante teve o maior efeito (P <0,001) na mudança de cor, enquanto o café apresentou o maior efeito (P <0,001) na translucidez. Conclusão: Apesar do grupo Zr-Hybrid tenha mostrado maior opacidade, ele ainda manteve sua estabilidade de cor e translucidez após envelhecimento acelerado em comparação com resinas compostas micro-híbridas e nanoparticuladas comercializadas. Todos os meios de infusão causaram descoloração e afetaram a translucidez das resinas compostas (AU)

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Objective: The aim of this study is to evaluate the effect of varying thickness and artificial aging on the color and translucency of cubic zirconia and lithium disilicate ceramics. Material and Methods: A total of 30 square shaped disks (12 mm x 12 mm) were fabricated from the cubic zirconia (Bruxzir Anterior) blank and lithium disilicate blocks (E.max CAD), used in three thicknesses (0.5mm, 0.8mm and 1mm). Portable spectrophotometer Vita Easyshade Advance was used to obtain color coordinates, which were substituted in formulas and used to calculate color change and translucency parameter values before and after aging (thermocycling for lithium disilicate and hydrothermal aging for cubic zirconia). Repeated measures Analysis of Variance (ANOVA) was used to study the effect of ceramic type, thickness, aging and their interaction on mean translucency parameter. Two-way (ANOVA) was used to study the effect of ceramic type, thickness and their interaction on mean color change (ΔE). Results: Statistical analysis showed that E.max CAD HT is more translucent than Bruxzir Anterior. Translucency decreased as thickness increased. There was a statistically significant decrease in TP after aging for both materials. Lithium disilicate showed statistically significant greater ΔE when subjected to aging than cubic zirconia, with both ΔE values being clinically imperceptible. As thickness increased, ΔE decreased. Conclusions: Thickness highly affected translucency and color of ceramics. As thickness increases, translucency parameter decreases and color change becomes less evident. Aging also causes a significant decrease in translucency parameter and induces color change however color changes are imperceptible. (AU)

Objetivo: O objetivo deste estudo é avaliar o efeito de diferentes espessuras e do envelhecimento artificial na cor e translucidez de cerâmicas de zircônia cúbica e dissilicato de lítio. Material e Métodos: Um total de 30 discos (12 mm x 12 mm) foram fabricados a partir de um bloco branco de zircônia cúbica (Bruxzir Anterior) e blocos de dissilicato de lítio (E.max CAD) em três diferentes espessuras (0,5mm, 0,8mm e 1mm). Um espectrofotômetro portátil Vita Easyshade Advance foi utilizado para obter as coordenadas de cores, que foram substituídas nas fórmulas e usadas para calcular os valores dos parâmetros de mudança de cor e translucidez antes e depois do processo de envelhecimento (termo ciclagem para dissilicato de lítio e envelhecimento hidrotérmico para zircônia cúbica). A análise de variância de medidas repetidas (ANOVA) foi usada para estudar o efeito do tipo de cerâmica, a espessura, o envelhecimento e a sua interação no parâmetro de translucidez média. Two-way (ANOVA) foi usado para estudar o efeito do tipo da cerâmica, espessura e sua interação na alteração de cor média (ΔE). Resultados: a análise estatística mostrou que a cerâmica E.max CAD HT é mais translúcida que Bruxzir Anterior. A translucidez diminuiu com o aumento da espessura. Houve uma diminuição estatisticamente relevante no TP após o envelhecimento para ambos os materiais. O dissilicato de lítio apresentou maior ΔE estatisticamente relevante quando submetido ao envelhecimento quando comparado com a zircônia cúbica, sendo ambos os valores de ΔE clinicamente imperceptíveis. Conforme a espessura aumentou, o ΔE diminuiu. Conclusão: a espessura afetou expressivamente na translucidez e cor das cerâmicas. À medida que a espessura aumentou, os parâmetros de translucidez diminuíram e a mudança de coloração se tornou menos evidente. O envelhecimento também causou uma diminuição significativa no parâmetro de translucidez das cerâmicas de zircônia cúbica e dissilicato de lítio. (AU)

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Abstract The aim of this study was to measure the nuchal translucency (NT) of canine fetuses to establish reference values ​​for healthy gestational processes and to verify its effectiveness in the diagnosis of congenital abnormalities. On day 34 of gestation, the NT of three fetuses from each of the 26 English bulldog female dogs was measured. The first fetus was the one located immediately cranial to the bladder, the second was selected from the left side of the abdomen, and the third from the right side. The reference values for healthy animals were offset using descriptive statistics. The diagnostic ability of the test to identify fetal malformations was studied using receiver operating characteristic curve analysis. Of the 26 litters, only 18 had healthy fetuses, 4 had fetuses with anasarca, 3 had fetuses with abdominal wall defects, and 1 had both types of abnormalities. The NT was higher in canine fetuses that presented anasarca in the litter than in normal litters (1.8 ± 0.77 mm vs. 1.4 ± 0.48 mm; P = 0.0249), with a cut-off value of NT > 1.45 mm (sensitivity = 61.54%, specificity = 70.18%). NT greater than 1.45 mm seems to be a diagnostic tool for the identification of anasarca during gestation of bulldogs. Considering the unprecedented use of this parameter in canine species and the limitations found during the study, further studies will be needed in order to use it on clinical practice.

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The aim of this study was to measure the nuchal translucency (NT) of canine fetuses to establish reference values ​​for healthy gestational processes and to verify its effectiveness in the diagnosis of congenital abnormalities. On day 34 of gestation, the NT of three fetuses from each of the 26 English bulldog female dogs was measured. The first fetus was the one located immediately cranial to the bladder, the second was selected from the left side of the abdomen, and the third from the right side. The reference values for healthy animals were offset using descriptive statistics. The diagnostic ability of the test to identify fetal malformations was studied using receiver operating characteristic curve analysis. Of the 26 litters, only 18 had healthy fetuses, 4 had fetuses with anasarca, 3 had fetuses with abdominal wall defects, and 1 had both types of abnormalities. The NT was higher in canine fetuses that presented anasarca in the litter than in normal litters (1.8 ± 0.77 mm vs. 1.4 ± 0.48 mm; P = 0.0249), with a cut-off value of NT > 1.45 mm (sensitivity = 61.54%, specificity = 70.18%). NT greater than 1.45 mm seems to be a diagnostic tool for the identification of anasarca during gestation of bulldogs. Considering the unprecedented use of this parameter in canine species and the limitations found during the study, further studies will be needed in order to use it on clinical practice.(AU)

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