Effect of post-rinsing time and method on accuracy of denture base manufactured with stereolithography

Abstract

PURPOSE This in vitro study investigates the effect of different post-rinsing times and methods on the trueness and precision of denture base resin manufactured through stereolithography. MATERIALS AND METHODS Ninety clear photopolymer resin specimens were fabricated and divided into nine groups (n = 10) based on rinsing times and methods. All specimens were rinsed with 99% isopropanol alcohol for 5, 10, and 15 min using three methods-automated, ultrasonic cleaning, and hand washing. The specimens were polymerized for 30 min at 40℃. For trueness, the scanned intaglio surface of each SLA denture base was superimposed on the original standard tessellation language (STL) file using best-fit alignment (n = 10). For precision, the scanned intaglio surface of the STL file in each specimen group was superimposed across each specimen (n = 45). The root mean square error (RMSE) was measured, and the data were analyzed statistically through one-way ANOVA and Tukey test (α < .05). RESULTS The 10-min automated group exhibited the lowest RMSE. For trueness, this was significantly different from specimens in the 5-min hand-washed group ( P < .05). For precision, this was significantly different from those of other groups ( P < .05), except for the 15-min automated and 15-min ultrasonic groups. The color map results indicated that the 10-min automated method exhibited the most uniform distribution of the intaglio surface adaptation. CONCLUSION The optimal postprocessing rinsing times and methods for achieving clear photopolymer resin were found to be the automated method with rinsing times of 10 and 15 min, and the ultrasonic method with a rinsing time of 15 min.

Effect of Postrinsing Times and Methods on Surface Roughness, Hardness, and Polymerization of 3D-Printed Photopolymer Resin

“…Agitation techniques, such as mechanical agitation or ultrasonic cleaning, involve actively moving or agitating the printed object in a rinsing solvent. 15 16 30 Agitation can enhance resin removal by dislodging any remaining resin particles and improving the overall cleanliness of the object's surface. 30 According to the findings of this study, hand washing may be comparable to immersion, whereas ultrasonic cleaning, which resembles agitation, produces smoother surface finishes.…”

“…The significance level (α) for all statistical tests was set at 0.05. Based on previous literature, 16 the sample size calculation for this study used an analytical software program (G Ã Power 3.1.9.2; Kiel University, Kiel, Schleswig-Holstein, Germany). A sample size of 10 per condition was required to obtain an effect size f of 0.45 and 80% power at 5% α error.…”

“…In their study, Ammoun et al 15 identified that hand washing with ultrasonics consistently produced better outcomes compared with automated methods. Regarding the impact of rinsing method and time on accuracy, Katheng et al 16 observed that the denture base resin was more precisely manufactured using the automated approach (rinsing times of 10 and 15 minutes) and the ultrasonic method (15 minutes). When examining the relationship between mechanical properties and rinsing method, “Yellow Magic” or centrifugal force revealed that specimens treated with IPA displayed reduced fracture loads in comparison to those who were washed.…”

Effect of Duplication Techniques on the Fitting Accuracy of CAD-CAM Milled, 3D-Printed, and Injection-Molded Mandibular Complete Denture Bases

“…Therefore, the DLP 3D printer was chosen in the current study instead of the SLA 3D printer for printing the duplicated dentures because it is fast and more accurate [30]. The printed denture bases were rinsed in 99% isopropyl ethyl alcohol for 5 min to remove any uncured resin material; however, increased rinsing time could result in printed object fissuring [31,32]. The printed dentures were dried and placed in a UV light-curing unit for 30 min to obtain full polymer conversion [31,32].…”

“…The printed denture bases were rinsed in 99% isopropyl ethyl alcohol for 5 min to remove any uncured resin material; however, increased rinsing time could result in printed object fissuring [31,32]. The printed dentures were dried and placed in a UV light-curing unit for 30 min to obtain full polymer conversion [31,32]. This technique's viability has been assessed in prior research [25,33].…”