Effect of Tooth-Structure Thickness on Light-Attenuation and Depth of Cure

Abstract

Newer bulk-fill composites claim a greater depth of cure than conventional resin based composites. To facilitate complete curing, the manufacturer of SonicFill (Kerr) recommends curing from the occlusal as well as the buccal and lingual surfaces of the tooth. The purpose of this study was to quantify the degree of curing light attenuation as it passes through natural tooth structure, and how this attenuation affects the depth of cure of different posterior resin composites. Ten non-carious extracted mandibular third molars were sectioned to produce a 5 mm thickness of buccal tooth structure. Sanding 0.5 mm increments from the flattened surface produced 4.5, 4.0, 3.5, 3.0, 2.5, 2.0, and finally 1.5 mm thick sections. A Bluephase G2 (Ivoclar) curing light with an 8mm diameter light guide set on High for 20 seconds was utilized for measurement of irradiance as it passed through different thicknesses of tooth structure and air. The average irradiance (mW/cm2) was measured with a MARC-RC Resin Calibrator with a 4mm diameter sensor (BlueLight Analytics). To measure depth of cure of a conventional hybrid composite (Herculite Ultra, Kerr) versus a bulk-fill hybrid composite (SonicFill) through varying thicknesses of tooth structure, composites were cured in a 4 mm diameter X 10.25 mm long split mold according to ISO 4049. A mean and standard deviation was determined per group. Data were analyzed with a 1-way ANOVA/Tukeys and 2-way ANOVA/Tukeys (alpha=0.05). One-way ANOVAs/Tukeys found a significant decrease in irradiance based on thickness of tooth structure or distance through air (p<0.001). A 2-way ANOVA/Tukeys found a significant decrease in depth of cure based on thickness of tooth structure (p<0.001) and on composite type (p<0.001) with no significant interaction (p=0.623). SonicFill had a significantly greater depth of cure than Herculite Ultra.

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Document Details

Document Type
Technical Report
Publication Date
Feb 26, 2015
Accession Number
AD1127857

Entities

People

  • Nicholas J. Hamlin

Organizations

  • Uniformed Services University of the Health Sciences

Tags

Communities of Interest

  • Biomedical
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Biocomposites
  • Composite Materials
  • Data Analysis
  • Dental Equipment
  • Dental Materials
  • Dentistry
  • Department Of Defense
  • Detectors
  • Diameters
  • Governments
  • Hardness
  • Materials
  • Measurement
  • Mechanical Properties
  • Medical Personnel
  • Particle Size
  • Physical Properties
  • Stresses
  • Teeth
  • Visible Spectra

Fields of Study

  • Materials science

Readers

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