Related Experiment Video
Updated: Jun 25, 2026
The Preparation and Properties of Thermo-reversibly Cross-linked Rubber Via Diels-Alder Chemistry
Published on: August 25, 2016
Comparison of urethane dimethacrylate monomer elution between indirect composites when subjecting to thermocycling
Nur Amalia Mohd Hanifah1, Sherrifah Nur Athirah A-Idid Syed Mohammed Idid1, Fatima Ahmed Qaid1,2
1Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia.
Context:
The use of resin-based computer-aided design and computer-aided manufacturing (CAD/CAM) blocks is increasing in restorative dentistry. However, the potential elution of urethane dimethacrylate (UDMA) into saliva and its associated safety implications remain insufficiently investigated.
Aims:
To identify and quantify the monomer elution of two different indirect composite blocks before and after thermocycling.
Settings And Design:
In vitro study.
Subjects And Methods:
Two composite CAD-CAM blocks were investigated: a resin-based composite block (RCB, Shofu HC Block) and a polymer-infiltrated ceramic network block (PICN, Vita Enamic). Twenty specimens from each material (n = 20) were prepared. All specimens (n = 40) were immersed in artificial saliva at 37°C for 24 h before thermocycling. Extractions were performed after 24 h of immersion and subsequently after 500 and 10,000 cycles of thermocycling. UDMA monomer elution was analyzed using high performance liquid chromatography (HPLC).
Statistical Analysis Used:
Kruskal-Wallis test.
Results:
No quantifiable level of UDMA was observed in either RCB or PICN before thermocycling. After 500 cycles of thermocycling, UDMA elution was identified in RCB (0.04 mg/mL), but remained undetectable in PICN. Following 10,000 cycles of thermocycling, both RCB and PICN showed UDMA release of 0.01 mg/mL. However, the Kruskal-Wallis test revealed no statistically significant differences among groups (P > 0.05).
Conclusions:
The highest UDMA elution occurred in RCB after 500 cycles of thermocycling. Despite differences in polymer structure, thermocycling did not significantly influence UDMA release in either material.
