Advantages and Disadvantages of the Thermoplastic Materials Used for the Production of Partial Prostheses

Abstract

Unlike traditional PMMA plastics, thermoplastic materials are not a product of a chemical reaction during the laboratory process. They are subjected to physical changes when heated, liquefied, and injected under pressure into a preheated cuvette, where they solidify before cooling. They are used for making aesthetic hooks and elastic skeletons for partial dentures. They can be combined with classic acrylic and model-cast prostheses. The purpose of this report is to trace the technology of placing an aesthetic hook made of thermoplastic material on a partial prosthesis made of acrylic plastic, indicating the main advantages and disadvantages of flexible prostheses. Biocetal constructions are an alternative to the traditional model of cast braces. It is an acetate thermoplastic polymer. In terms of construction features, Biocetal prostheses resemble model-cast clamps in the Ney system. The most significant advantages of flexible partial dentures are due to the properties of thermoplastic materials. Their strength and flexibility make inserting and removing the prosthesis easier. The fact that they are not the product of a chemical reaction increases their biological tolerance. Hooks are almost indistinguishable from abutment teeth. In addition to the above advantages, flexible dentures also have their drawbacks. A large percentage of masticatory pressure is absorbed by the soft tissues of the prosthetic field, which causes increased atrophy of bone tissue. Plastic hooks on the abutment teeth press on the mucosa, the gingival margin separates from the tooth, and gradually over time a pocket can form, leading to an inflammatory process. Despite the listed disadvantages of flexible prostheses, knowing and following the clinical and laboratory protocol significantly minimizes the possibility of their manifestation.