Related Experiment Video
Updated: Feb 8, 2026
Evaluating the Effects of Different Polishing Methods on Color Stability of Dental Restorations in Pediatric Dentistry
Published on: June 6, 2025
Comparison of Cuspal Deflection and Microleakage of Premolar Teeth restored with Three Restorative Materials
Ebrahim Yarmohamadi1, Pegah R Jahromi2, Mahdi Akbarzadeh3
1Department of Restorative Dentistry, Dental School, Hamadan University of Medical Sciences, Hamadan, Islamic Republic of Iran.
Aim:
This study aimed to assess cuspal deflection and micro-leakage of mesio-occluso-distal (MOD) cavities in premolar teeth restored with three different tooth-colored restorative materials to determine the effect of polymerization shrinkage stress over time.
Materials And Methods:
The MOD cavities (4 mm depth) were prepared in 30 sound human maxillary premolars. The teeth were randomly divided into three groups (n = 10). The teeth were then restored with Filtek P60 (group I), X-tra fil (group II), and Admira Fusion x-tra (group III). Cuspal deflection was assessed after 5 minutes, 24 hours, 48 hours, and 7 days by measuring the intercuspal distance. After restoring the teeth, they were subjected to 1,000 thermal cycles and were then immersed in 2% methylene blue for 24 hours. After vertical section of teeth, they were observed under a stereomicroscope to assess micro-leakage. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey's honest significant difference (HSD) post hoc test. Friedman test was used to compare different time points in each group and nonparametric Mann-Whitney test was applied to assess microleakage (a < 0.05).
Results:
The mean cuspal deflection was significantly different in the three groups (p < 0.001). The highest deflection was noted in Filtek P60 (14.8 ± 1.9) and the lowest was noted in Admira Fusion x-tra (7.4 ± 1.4 μm). Cuspal deflection significantly decreased after 7 days, but did not return to the baseline value. Admira Fusion x-tra showed significantly less deflection after 7 days (p < 0.001), but the other two groups were the same (p = 0.3). Microleakage was not significantly different among the three groups (p > 0.05).
Conclusion:
The lowest cuspal deflection was noted in Admira Fusion x-tra, although marginal microleakage was not significantly different among the groups.
Clinical Significance:
As the lowest cusp deflection was noted in Admira Fusion x-tra, this restorative material can be suitable for esthetic restoration of extensive posterior cavities.
Related Concept Videos
01:19Restorative Care
01:15Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin...
01:19Deflection of a Beam
Singularity functions, described in an earlier lesson, are powerful mathematical tools that represent discontinuities within a function commonly encountered in structural loading...
01:13Maximum Deflection
The maximum deflection occurs at a specific point, known as point O, where the tangent to the deflection curve is horizontal. To find point O, the slope of the tangent at any...
02:57The Sense of Self: Reflected Self-Appraisal and Social Comparison
01:13Multiple Comparison Tests
It would be easy to compare two samples using a significance alpha level of 0.05. In other words, there is only one sample pair to be compared. However, it would be difficult to identify a significantly different sample if the number...