{"id":43115,"date":"2026-08-05T06:57:33","date_gmt":"2026-08-05T06:57:33","guid":{"rendered":"https:\/\/uomosul.edu.iq\/en\/dentistry\/?p=43115"},"modified":"2026-08-18T07:11:57","modified_gmt":"2026-08-18T07:11:57","slug":"masters-thesis-defense-at-the-college-of-dentistry-on-the-flexural-strength-microhardness-and-surface-roughness-of-3d-printed-denture-base-resin-under-varying-exposure-times-and-post-polymerizatio","status":"publish","type":"post","link":"https:\/\/uomosul.edu.iq\/en\/dentistry\/2026\/08\/05\/masters-thesis-defense-at-the-college-of-dentistry-on-the-flexural-strength-microhardness-and-surface-roughness-of-3d-printed-denture-base-resin-under-varying-exposure-times-and-post-polymerizatio\/","title":{"rendered":"Master’s Thesis Defense at the College of Dentistry on the Flexural Strength, Microhardness, and Surface Roughness of 3D-Printed Denture Base Resin under Varying Exposure Times and Post-Polymerization Methods"},"content":{"rendered":"

On Wednesday, August 5, 2026, the Department of Prosthodontics at the College of Dentistry, University of Mosul, witnessed the defense of the master\u2019s thesis entitled:\u00a0 “Flexural Strength, Microhardness, and Surface Roughness of 3D-Printed Denture Base Resin under Varying Exposure Times and Post-Polymerization Methods.”
\nThe thesis was submitted by the student Noor Al-Huda Saadallah Mohammad Saleh Hussein Al-Hamdani.
\nThe study aimed to evaluate the impact of layer exposure duration during 3D printing, along with post-curing duration and temperature, on the mechanical and surface properties of denture base resin fabricated using Liquid Crystal Display (LCD) 3D-printing technology.
\nThe study involved the fabrication of 140 standardized specimens using an LCD 3D printer and Centric denture base resin at a wavelength of 405 nm, under two distinct layer exposure times (2.5 seconds and 5 seconds). The specimens were categorized into four post-curing conditions: an uncured control group, a UV-cured group without heating, and UV-cured groups with thermal post-curing at 40^\\circ\\text{C} and 60^\\circ\\text{C} for 20 and 10 minutes, respectively.
\nFlexural strength was assessed via the three-point bending test in accordance with ISO 1567 standards, microhardness was measured using the Vickers hardness test, and surface roughness was evaluated using a digital profilometer. Statistical analysis was performed using One-Way Analysis of Variance (ANOVA) followed by Duncan\u2019s post-hoc test at a significance level of p < 0.05.
\nThe results demonstrated an increase in flexural strength and Vickers microhardness values with higher post-curing temperatures, reaching their peak values at 60^\\circ\\text{C} (89.9\\text {MPa} for flexural strength and 17.4\\text {VHN} for microhardness). A similar improvement was observed with increased post-curing duration.
\nSurface roughness measurements showed no statistically significant changes, remaining within clinically acceptable limits (\\text {Ra} < 0.2\\ \\mu\\text{m}) across all post-curing conditions. The findings indicate that extending post-curing duration and raising its temperature significantly enhance the mechanical durability of 3D-printed denture base resins. Furthermore, the study highlighted an integrated interaction among layer exposure time, post-curing duration, and post-curing temperature in determining the overall mechanical performance of the material.
\nThe Examination Committee was chaired by Prof. Dr. Nada Zuhair Mohammad, with Assoc. Prof. Dr. Ammar Khalid Jamal Al-Din and Assoc. Prof. Dr. Lama Mudafar Anwar as members. Prof. Dr. Ahmed Asim Saeed served as the thesis supervisor and was also a member of the defense committee.
\nAt the conclusion of the defense, the thesis was successfully accepted following the completion of the required modifications.<\/p>\n\n\t\t