Related Experiment Video
Updated: Aug 1, 2026
An Improved Mechanical Testing Method to Assess Bone-implant Anchorage
Published on: February 10, 2014
The Effect of Crown Design on Fracture Strength and Mode of Implant-supported Molar Crown Bonded to Titanium-based
Nh Kamar Affendi1, Ay Abdul Hakim2, R Ahmad3
1Centre of Restorative Dentistry Studies, Faculty of Dentistry, Universiti Teknologi MARA (UiTM), Kampus Sungai Buloh, Jalan Hospital, Sungai Buloh, Selangor, Malaysia, Phone: +60 361266545, e-mail: hafizah_kamar@uitm.edu.my, Orcid: https://orcid.org/0000-0001-9883-9549.
Aim:
This in vitro study aims to evaluate fracture strength and fractographic analysis of implant crown fabricated as monolithic cement-retained (MCV), monolithic screw retrievable-cement retained (MSV), and bilayer system monolithic (BSV), all bonded to Ti-base abutment.
Materials And Methods:
A total of 30 specimens were included, with sample size calculated based on an alpha level of 0.05 and statistical power of 80%. The specimens were equally distributed into three groups: control (MCV, n = 10) and test groups (MSV, n = 10, and BSV, n = 10). All specimens underwent thermal aging and were subjected to fracture strength testing. Data normality was assessed using the Shapiro-Wilk test. As the data were not normally distributed, group comparisons were analyzed using the Kruskal-Walli's test. Post-hoc pairwise comparisons (MCV vs MSV, MCV vs BSV, and MSV vs BSV) were performed using the Mann-Whitney U-test with Bonferroni correction. Fracture modes were further analyzed by scanning electron microscopy (SEM) and categorized based on the percentage of remaining crown material.
Results:
The MCV crowns demonstrated the highest fracture strength (2955.84 ± 310.93 N), followed by MSV (2846.11 ± 370.59 N) and BSV (1994.70 ± 95.44 N). Statistically significant differences in fracture strength were observed among the groups (p < 0.001). Post-hoc analysis showed that BSV had significantly lower fracture resistance than both MCV and MSV (p < 0.001), while no significant difference was found between MCV and MSV (p = 1.000). Regarding fracture mode, half of MCV specimens had >75% crown remaining, BSV exhibited 50-75% remaining, and MSV had <50% remaining. The SEM analysis revealed catastrophic fracture patterns for both MCV and MSV, whereas BSV exhibited complex failure patterns.
Conclusion:
Implant crown design significantly impacts fracture resistance and failure modes. The MCV crowns exhibited superior strength, whereas BSV crowns, despite lower fracture strength, maintained intact zirconia abutment, offering repairability of the superstructure.
Clinical Significance:
Monolithic cemented crowns may be preferred in high-load areas for their superior strength, while bilayer designs with intact zirconia abutments offer retrievability and repair potential, making them suitable for lower-load regions. How to cite this article: Affendi NHK, Hakim AYA, Ahmad R, et al. The Effect of Crown Design on Fracture Strength and Mode of Implant-supported Molar Crown Bonded to Titanium-based Abutment. J Contemp Dent Pract 2025;26(6):565-672.
Related Concept Videos
01:18The Bone Matrix
01:14Cranial Bones: Superior and Posterior View
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
01:23Design of Prismatic Beams for Bending