Jove
Visualize
Contact Us

Related Experiment Videos

Effect of variable light intensity on composite shrinkage.

J B Dennison1, P Yaman, R Seir

  • 1Department of Cariology, Restorative Sciences and Endodontics, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1597, USA.

The Journal of Prosthetic Dentistry
|December 6, 2000
PubMed
Summary

Sequentially increasing light intensity during dental composite curing significantly reduces polymerization shrinkage. This method ensures adequate depth of cure without compromising mechanical properties, offering a promising alternative to standard high-intensity curing.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Repair or Observation of Resin Margin Defects: Clinical Trial After Five Years.

Operative dentistry·2019
Same author

Gingival Health of Porcelain Laminate Veneered Teeth: A Retrospective Assessment.

Operative dentistry·2019
Same author

Effect of Light-Curing Exposure Time, Shade, and Thickness on the Depth of Cure of Bulk Fill Composites.

Operative dentistry·2017
Same author

Polymerization shrinkage and depth of cure of bulk fill flowable composite resins.

Operative dentistry·2013
Same author

Inorganic and prepolymerized filler analysis of four resin composites.

Operative dentistry·2013
Same author

Physical property evaluation of four composite materials.

Operative dentistry·2013
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Area of Science:

  • Dental Materials Science
  • Polymer Chemistry
  • Biomaterials Engineering

Background:

  • Polymerization shrinkage in dental composites is a significant clinical issue, potentially leading to adverse outcomes like microleakage and secondary caries.
  • High-intensity light curing improves cure depth and mechanical properties but exacerbates shrinkage.
  • Optimizing light curing protocols is crucial for mitigating shrinkage without sacrificing material performance.

Purpose of the Study:

  • To evaluate the impact of sequentially increasing light intensity on polymerization shrinkage in hybrid and microfill dental composites.
  • To assess the effectiveness of different light intensity curing sequences on the depth of cure using Knoop hardness testing.

Main Methods:

  • Polymerization shrinkage was measured using a linometer on samples subjected to four curing protocols: full-intensity control, low-intensity control, and two test groups with incrementally increasing light intensity.

Related Experiment Videos

  • Knoop hardness testing was employed to evaluate the degree of cure for each composite material under the different light intensity sequences.
  • Statistical analysis included one-factor ANOVA and Tukey's multiple comparisons test to determine significant differences between groups.

    • Main Results:

    • A significant reduction in mean linear shrinkage was observed in all tested sequential light intensity protocols compared to the full-intensity control group for both composite types (P<.05).
    • No significant differences in shrinkage were found among the three non-full-intensity protocols for either composite material.
    • Knoop hardness values indicated that the full-intensity control and the most graduated sequential protocol (25% for 10s, 50% for 10s, 100% for 20s) achieved comparable and superior cure depths.

    Conclusions:

    • A sequential light intensity curing strategy, specifically 10s at 25%, 10s at 50%, and 20s at 100% intensity, effectively minimizes polymerization shrinkage in dental composites.
    • This optimized curing protocol achieves a sufficient depth of cure, comparable to full-intensity curing, thus not compromising the material's performance.
    • Implementing graduated light intensity curing presents a viable method to reduce adverse effects associated with polymerization shrinkage in dental restorations.