Although this jelly-like material was elastic, it required a complicated procedure to be used as an impression material. That is when agar, a reversible hydrocolloid manufactured from algae, was introduced in dentistry. Thus, there was always a need for an impression material that could remain elastic even after setting. All the impression materials used until that date became rigid after setting and could not copy the oral tissues accurately. Still, the problem with this material was that it was rigid and could not reproduce undercut areas. Then in 1857, Charles Stent created a thermoplastic modeling compound similar to today's impression compound. Wax was the only impression material used in dentistry until the mid-19th century when gutta-percha first appeared. The final restoration or prosthesis fit depends on how accurately the impression material has recorded the tissue details.
Particular treatment, such as removable and fixed prostheses, can be executed thanks to dental casts. This procedure provides a tridimensional and accurate mouth replica, allowing dental work even in the absence of the patient.ĭental models enable dentists to perform a better diagnosis and treatment planning since the teeth can be meticulously visualized and studied from angles that are difficult to see in the patient's mouth. Impression materials are used to copy the teeth and surrounding oral structures by creating a dental impression poured with dental plaster to fabricate a dental cast.