We have received the following three issues regarding the product. Let's look into the causes of these issues and how to resolve them:

1. Strong odor
2. Liquid component causes corrosion on worktops
3. Cured material is hard and brittle

Main Ingredients

• Powder: Polymethyl Methacrylate (PMMA)
• Liquid: Methyl Methacrylate (MMA) monomer

This self-curing resin is widely used for fabricating dental models, custom trays, temporary crowns and bridges. Featuring rapid room-temperature self-polymerization, it facilitates operations for dental technicians in clinics and dental laboratories.

1. Issue: Strong Odor

Cause Explanation

A pungent odor is a typical characteristic of this self-curing resin. The unpleasant smell mainly derives from MMA monomer contained in the liquid component. Although the odor is strong, it volatilizes quickly under well-ventilated conditions, and the product complies with safety standards for medical materials.

Recommendations

• Working Environment: Operate exclusively in a fume hood or a well-ventilated workspace.
• Personal Protection: Operators are advised to wear activated carbon masks to effectively absorb most volatile organic compounds.
• Operation Protocol: Strictly follow the powder-to-liquid ratio of 1:0.8. Excess liquid will lead to extra monomer volatilization and intensify the odor. Perform compaction only when the material reaches the dough stage, as most monomers have participated in chemical reactions by this stage, resulting in a significant reduction of volatilization.

2. Issue: Worktop Corrosion Caused by Liquid

Cause Explanation

MMA monomer in the liquid component is a powerful organic solvent. It can dissolve common paint and varnish coatings, and corrode certain plastics (e.g., polystyrene), leaving melted marks on work surfaces.

Recommendations

• Worksurface Modification: Lay glass sheets, stainless steel plates or professional silicone anti-slip mats on the working area. These materials are resistant to organic solvent corrosion and easy to clean.
• Prompt Cleaning: Wipe off any spilled liquid immediately with a dry cloth to prevent prolonged contact with the worktop.

3. Issue: Cured Material Being Hard and Brittle

Cause Explanation

This product is Type II rigid model resin. High hardness is an inherent physical property of such materials. Designed for manufacturing model bases and custom trays, it requires sufficient hardness and rigidity to resist deformation during subsequent trimming and intraoral application.

Excessive brittleness (prone to fracture) of the cured material is generally attributed to improper operation:

• Inaccurate powder-liquid ratio (either excess powder or liquid will compromise the mechanical strength).
• Humid working environment: The self-curing reaction of the resin is highly sensitive to moisture.

Recommendations

• Precise Proportioning: Use measuring tools to maintain the powder-to-liquid weight ratio at 1:0.8.
• Optimal Operation Timing: Carry out moulding when the material turns dough-like. Operation at the stringy stage or late hardening stage will adversely affect the final strength of the finished product.