Dental putty refers to impression materials used to create a 3D model of oral structures like teeth preparations, implants, or edentulous ridges. Putties have a thick, doughy consistency that holds shape once molded onto dental regions.
In simpler terms, putty acts like a pliable clay that captures precise anatomical detail when pressed against teeth or gums. After it sets, the impression gets sent to a dental lab that pours plaster or scans the putty replica. This creates working casts, enabling technicians to fabricate well-fitting dental appliances like crowns, bridges, dentures, and nightguards later.
The main constituent of dental putty is an elastic-deformable silicone polymer like polyvinylsiloxane. This gives it stretch and flexibility to flow around oral topography yet has sufficient stiffness to maintain dimensional stability afterward, registering details accurately. The putty comes as two pastes - a base and catalyst - that dentists mix chairside. Once combined, cross-linking chemical curing commences. The putty first passes through a putty-like phase with clay consistency, allowing about 2 minutes for positioning in the mouth. Then, as the setting progresses, the material transforms into an elastic solid. This captures intricacies in a detailed and durable impression.
Modern polyvinylsiloxane putties have optimal properties for perfect, detailed impressions even under moist, variable temperature conditions - important given the dynamic oral environment. The material’s limited compression set also maintains precision dimensions well after removal despite its elasticity. And the putty remains adequately soft through the working/setting stages to avoid discomfort or tissue trauma. Together, these favorable handling and physical properties make modern silicone putties a top impression material choice to produce accurate working models.
While valued for accuracy, polyvinylsiloxane putties also have some limitations. As moisture-activated hydrosilication polymers, they have finite working times and must be set undisturbed. Bulky putty consistency also poses potential breathing risks if positioned improperly in the pharynx. Some patients report gagging, especially with exaggerated reflexes. Additionally, the putties exhibit low tear strength and may rip if removed incautiously from undercuts. However, modern plastic tray carriers help dentists place and remove impressions more easily. Incremental putty addition into stock trays also reduces bulky masses. With care in handling, silicone putties remain easy to manipulate, providing detailed and durable replicas crucial for well-fitting restorations.
In summary, dental putty serves an important role as the interface material molding perfectly within the patient’s mouth to enable well-fitting indirect restorations made later in the lab. Its doughy-to-elastic progression allows clinician manipulation followed by stable detail capture - critical prerequisites for prosthetic fabrication. Continued improvement in silicone chemistry and handling continues to expand putty impression applications and ease routine use. Both dentists and patients ultimately benefit from the tissue compatibility, precision, and reliability of dental putties that afford a range of restoration workflows.