Oral Maxillofacial Prosthodontics is the branch of Prosthodontics concerned with the restoration and/or replacement of stomatognathic and associated facial structures by artificial substitutes, that may or may not removable.
Maxillofacial Prosthetic Materials
- Acrylic resin
- Acrylic copolymer
- Polyurethane elastomers
- Silicone elastomers
a. Room temperature vulcanizing (RTV)
b. Heat vulcanizing (HTV)
Acrylic resin
Acrylic resins are employed for specific types of facial defects, particularly those in which little movement occurs in the tissue bed during function (e.g. fabrication of orbital prosthesis) and for temporary facial prostheses.
Acrylic copolymer
Acrylic copolymers are soft and elastic but have not received wide acceptance because of poor edge strength, poor durability and being subject to degradation when exposed to sunlight. In addition complete restoration is often tacky predisposing to direct collection and staining.
Polyurethane elastomers
Polyurethane elastomers contain a urethane linkage. The reactants are a polymer terminating with hydroxyl group and others terminating with isocyanate in the presence of a catalyst. They can be synthesized with a wide range of physical properties by varying the reactants and their amounts.
Room temperature vulcanizing silicone elastomers (RTV)
They are viscous silicone polymer including a filler, a stannous octate catalyst and an orthoalkyl silicate cross linking agent. Fillers are usually diatomaceous earth which improves strength.
Heat-temperature vulcanizing silicone elastomers (HTV)
Designed for higher tear resistance in engineering applications, this type of polymer requires more intense mechanical milling of the solid HTV stock elastomers compared with the soft putty RTV silicone, especially for incorporating the required catalyst for cross link.
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