Defects in automixed addition silicone elastomers prepared by putty-wash impression technique

Area of Science:

• Dental Materials Science
• Polymer Chemistry
• Biomaterials Engineering

Background:

• Voids in dental impressions can compromise accuracy and lead to restorative failures.
• Addition silicone elastomers are widely used for dental impressions due to their favorable properties.
• Automixing systems aim to improve handling and reduce defects compared to traditional hand-mixing.

Purpose of the Study:

• To investigate and quantify void formation in dental impressions made with five automixed addition silicone elastomers.
• To compare void prevalence between automixed and hand-mixed addition silicone materials.
• To identify specific automixed materials with superior performance regarding void reduction.

Main Methods:

• Impressions were fabricated using the putty-light body technique on standardized stainless-steel cylinders.
• Void counts were performed at a specific site using a stereomicroscope at 7x magnification over three days.
• Comparison groups included hand-mixed addition silicone and hand-mixed versions of the automixed materials.

Main Results:

• Automixed addition silicone elastomers generally produced significantly fewer voids than hand-mixed materials.
• Significant differences in void counts were observed among the tested automixed materials.
• Express exhibited a higher void count, while President Jet demonstrated the lowest void count.

Conclusions:

• Automixing technology is effective in reducing void defects in addition silicone elastomeric impressions.
• Material selection is crucial, as void formation varies between different automixed systems.
• Automixed materials offer a significant advantage over hand-mixing in producing void-free dental impressions.