7 September، 2025
Master’s Thesis Defense Entitled: “Fitness and Bond Strength of All-Ceramic Crowns Fabricated with Different Processing Systems”
On Sunday, September 7, 2025, the Department of Conservative Dentistry at the College of Dentistry, University of Mosul, held the defense of the master’s thesis entitled: “On the Marginal Fit and Bond Strength of All-Ceramic Crowns Fabricated Using Different Processing Systems.”
The thesis, submitted by Murtadha Mohammed Alwan Khattab, examined the effect of various processing systems on the shear bond strength and the internal and external marginal fit of full-ceramic crowns before and after exposure to artificial aging (thermocycling).
The study aimed to evaluate and compare the influence of material type (E.max Press, E.max CAD, 3D-printed resin nanoceramic, and lithium disilicate–reinforced zirconia (ZLS)) and manufacturing technique (pressing, CAD/CAM, and 3D printing) on the shear bond strength of resin cement, in addition to the internal and external marginal adaptation values of extra-coronal restorations.
The findings indicated that thermocycling had varying effects on bond strength and fit depending on the material type and fabrication technique. E.max CAD recorded the highest shear bond strength prior to thermocycling, while the 3D printing technique demonstrated superior internal adaptation both before and after thermocycling. No statistically significant differences were observed in marginal adaptation before and after thermocycling. The study concluded that material selection and fabrication technique play a critical role in determining bond strength and the internal and external marginal fit of all-ceramic crowns, underscoring the need to consider these factors when making clinical decisions.
The examination committee was chaired by Assist. Prof. Dr. Alaa Idrees Dawood/ College of Dentistry/ University of Mosul, with membership of Assist. Prof. Dr. Najwan Fadel Shihab/ College of Dentistry/ University of Mosul, Prof. Dr. Nadia Muzafar Ahmed/ College of Dentistry / University of Mosul, and under the supervision and membership of Assist. Prof. Dr. Nadia Hameed Hassan/ College of Dentistry/ University of Mosul.
The thesis was accepted after the required revisions were completed.
“Achieved targets of the Sustainable Development Goals: Goal 3, 4, 9
