Adhesive performance of a multi-mode adhesive system: 1-year in vitro study

Area of Science:

• Dental Materials Science
• Adhesive Dentistry
• Biomaterials

Background:

• Assessing the long-term stability of dental adhesives is crucial for clinical success.
• Universal adhesives offer versatility but require optimal application techniques.
• Dentine bonding effectiveness can be influenced by moisture and application protocols.

Purpose of the Study:

• To evaluate the adhesive stability of a multi-mode one-step adhesive on human dentine.
• To compare microtensile bond strength (μTBS), nanoleakage, and matrix metalloproteinases (MMPs) activation with different bonding techniques.
• To determine the effect of ageing (24h, 6 months, 1 year) on adhesive performance.

Main Methods:

• Human molars were bonded using Scotchbond Universal in self-etch, etch-and-rinse (wet/dry), and Prime&Bond NT (control) modes.
• Specimens were tested for μTBS using the non-trimming technique after 24h, 6 months, and 1 year.
• Interfacial nanoleakage and MMP expression were analyzed in additional specimens.

Main Results:

• No baseline differences were observed between groups.
• After 1 year, Scotchbond Universal (self-etch) and Prime&Bond NT exhibited superior μTBS.
• Scotchbond Universal in self-etch mode showed the least nanoleakage over time.
• MMP activation was detected with all tested adhesives.

Conclusions:

• The self-etch application approach improves the long-term stability of the tested universal adhesive on dentine.
• Using a self-etch strategy enhances the bonding effectiveness of universal adhesive systems.
• This finding supports the self-etch technique for durable dentine bonding with universal adhesives.