Evaluation of restorative materials using a new perfusion system

Area of Science:

• Dental Materials Science
• Cariology
• Restorative Dentistry

Background:

• Secondary caries is a major cause of restoration failure.
• Accurate in vitro models are needed to assess the caries-inhibiting potential of restorative materials.
• Simulating oral pH fluctuations is key to realistic demineralization studies.

Purpose of the Study:

• To evaluate a novel perfusion device for simulating intraoral acid attacks.
• To standardize a dentin demineralization procedure for in vitro testing.
• To determine the secondary caries inhibition of different restorative materials.

Main Methods:

• Three restorative materials (fluoride adhesive/composite, experimental adhesive/composite, glass-ionomer cement) were used to restore Class II cavities.
• A dynamic perfusion device alternated demineralizing and non-demineralizing solutions.
• Dentin demineralization was analyzed using microradiography, assessing lesion morphology and mineral loss.

Main Results:

• Demineralization increased from fluoride composite < experimental composite < glass-ionomer cement.
• Fluoride-containing materials exhibited a protective effect with more caries inhibition zones (CIZs) and less mineral loss.
• Glass-ionomer cement showed frequent CIZs but high overall demineralization due to poor marginal adaptation.

Conclusions:

• The dynamic perfusion device effectively simulates oral pH changes for in vitro demineralization studies.
• Fluoride in restorative materials offers limited protection against secondary caries.
• Excellent marginal adaptation of restorative materials is critical for preventing restoration failure and secondary caries.