Novel antibacterial low-shrinkage-stress resin-based cement

Abstract

Objective: A low-shrinkage-stress resin-based cement with antibacterial properties could be beneficial to create a cement with lower stress at the tooth-restoration interface, which could help to enhance the longevity of the fixed dental restoration by reducing microleakage and recurrent caries. To date, there has been no report on the development of a low-shrinkage-stress and bio-interactive cement. Therefore, the objectives of this study were to develop a novel low-shrinkage-stress resin-based cement containing dimethylaminohexadecyl methacrylate (DMAHDM) and investigate the mechanical and antibacterial properties for the first time.

Methods: The monomers urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE) were combined and denoted as UV resin. Three cements were fabricated: (1) UV+ 0%DMAHDM (experimental control); (2) UV+ 3%DMAHDM, (3) UV+ %5DMAHDM. RelyX Ultimate cement was used as commercial control. Mechanical properties and Streptococcus mutans (S. mutans) biofilms growth on cement were evaluated.

Results: The novel bio-interactive cement demonstrated excellent antibacterial and mechanical properties. Compared to commercial and experimental controls, adding DMAHDM into the UV cement significantly reduced colony forming unit (CFU) counts by approximately 7 orders of magnitude, metabolic activities from 0.29 ± 0.03 A₅₄₀/cm² to 0.01 ± 0.01 A₅₄₀/cm², and lactic acid production from 22.3 ± 0.74 mmol/L to 1.2 ± 0.27 mmol/L (n = 6) (p < 0.05). The low-shrinkage-stress cement demonstrated a high degree of conversion of around 70 %, while reducing the shrinkage stress by approximately 60%, compared to a commercial control (p < 0.05).

Conclusions: The new antibacterial low-shrinkage-stress resin-based cement provides strong antibacterial action and maintains excellent mechanical properties with reduced polymerization shrinkage stress.

Clinical significance: A low-shrinkage-stress resin-based cement containing DMAHDM was developed with potent antibacterial effects and promising mechanical properties. This cement may potentially enhance the longevity of fixed dental restoration such as a dental crown, inlay, onlay, and veneers through its excellent mechanical properties, low shrinkage stress, and strong antibacterial properties.

Keywords: Antibacterial; Bio-interactive; Caries; Low polymerization stress; Oral biofilms; Resin cement.