RESUMO
PURPOSE: Many factors can affect the aesthetics of dental restorations, including the instrumental techniques used in shade matching, and can lead to clinical failure. The aim of this study was to investigate the effectiveness of using the cross-polarization digital photograph technique and intraoral scanners for shade matching, and also evaluate the effect of the level of clinical experience on shade matching success. MATERIALS AND METHODS: Color analysis was performed on the maxillary right central incisors of 10 subject models with Vita Easyshade. Intraoral scanning was performed 10 times on each model using TRIOS 3 and color analysis was performed from the same spot. Then cross-polarized and non-polarized photographs of the models were taken with standard settings using a gray reference card. Each shade tab of the Vita System 3D-Master scale was also photographed with two different polarization techniques. Four groups (n = 12), including prosthodontics faculty staff, postgraduate students in prosthodontics, undergraduate students, and dental technicians matched the shade tabs and the model photographs obtained with both techniques on a standardized computer screen. Finally, the color differences between the shade tabs and maxillary central incisors matched by observers from four different groups were recorded using a colorimeter, Classic Color Meter, in accordance with the CIELAB system and CIEDE2000 (ΔE00) values were calculated. The data were compared with the acceptability threshold of 1.80 for ΔE00. The data obtained from the observers were analyzed with IBM SPSS Statistics 26.0 Release Notes program. Independent Samples t-test was used to compare normally distributed data according to binary groups. The level of significance was 0.05. RESULTS: A statistically significant difference was found in the shade matching on photographs taken with different techniques in postgraduate students (p = 0.02). Also, there was a statistically significant difference in success between the groups that made shade matching based on photographs obtained with the non-polarization technique (p = 0.00). The undergraduate students achieved statistically significantly lower results than all other groups (ΔE00 = 5.57 ± 1.07). The kappa value between the intraoral scanner and spectrophotometer results was 0.10, and this value was not statistically significant (p = 0.32). CONCLUSIONS: The cross-polarization technique used especially for shade matching is not superior to the non-polarization technique. Academic and clinical experience might be correlated with shade-matching success with the non-polarization technique. The clinical acceptability threshold could not be achieved in the shade matchings made on digital photographs taken with both techniques. Shade matching performed with an intraoral scanner did not yield reliable results.
RESUMO
Purpose: The purpose of this study was to examine the level of evidence (LOE) characteristics and associated factors that change over time in three leading prosthodontics journals. Materials and methods: Articles published in The Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontics (JP) in 2013 and 2020 were reviewed by eight independent reviewers. After applying exclusion and inclusion criteria, the number of authors, the corresponding author's educational degree, corresponding author's origin in each clinical research article were recorded. The included articles were rated by reviewers according to the level of evidence criteria and proposed level of evidence-associated factors. Descriptive statistics, univariable, and binary logistic regression analysis were performed to investigate dependent variables and potentially associated factors. All independent variables with a significant effect were analyzed by using a multivariable test. The entry and exit alpha level were set at αE = 0.15. The statistical significance was set at α = 0.05. Results: A total of 439 articles from 3 selected journals for the years studied met the inclusion criteria. The percentages of level 1, 2, 3, 4, and 5 articles were 2.7 %, 11.4 %, 9.6 %, 13.4 % and 62.9 %, respectively. Univariable analysis results demonstrated significant associations related to the number of authors (P = 0.005), the corresponding author's educational degree (P = 0.022), and the corresponding author's geographic origin (P = 0.042). Multivariable analysis results demonstrated significant associations related to the number of authors (P = 0.002), and the corresponding author's geographic origin (P = 0.014). Conclusions: The number of authors, CA degree, and CA origin had a significant association with the LOE of included prosthodontic studies. Although there was an increase in the number of publications from 2013 to 2020, the level of evidence trend shows no improvement over the years.