Dental impression material utilizing ruthenium metathesis catalyst

A composition for use as a dental impression material, comprising:

• a base paste including a polymerizable resin comprising at least one polydimethylsiloxane functionalized with cycloalkenyl groups curable by ring-opening metathesis polymerization and selected from the group consisting of:
• polydimethylsiloxane tethered and end-capped with the groups, tri-functional polydimethylsiloxane end-capped with the groups, and quadri-functional polydimethylsiloxane end-capped with the groups, and an inorganic dental filler system;
• and
• a catalyst paste including a ruthenium carbene complex catalyst dissolved in a solvent which is miscible wit the base paste and an inorganic dental filler system, wherein the catalyst is capable of initiating the ring-opening metathesis polymerization of the composition to form a cured dental impression material.

A composition for use as a dental impression material, comprising:

• a base paste including a polymerizable resin comprising at least one polydimethylsiloxane functionalized wit cycloalkenyl groups curable by ring-opening metathesis polymerization and selected from the group consisting of:
• polydimethylsiloxane tethered and end-capped with the groups, td-functional polydimethylsiloxane end-capped wit the groups, and quadri-functional polydimethylsiloxane end-capped with the groups, and an inorganic dental filler system;
• and
• a catalyst paste including a substituted ruthenium carbene complex with a substituted ligand having a basicity higher than tricyclohexylphosphine, the complex dissolved in a solvent which is miscible with the base paste, and an inorganic dental filler system,
• wherein the catalyst is capable of initiating the ring-opening metathesis polymerization of the composition, and
• wherein the composition achieves a recovery after deformation of at least 96.5% within 20 minutes of contacting a solution of 1% or less of an oxidizable sulfur-containing compound in hexane.