Porosity
The presence of voids or pores within a set dental material, which can arise from inadequate mixing, entrapment of air, or incomplete condensation, negatively affecting mechanical and optical properties.
Full Definition
Porosity in dental materials refers to internal or surface voids that develop during mixing, manipulation, or processing. In cast metal alloys, porosity arises from shrinkage during solidification or gas entrapment. In acrylic resins and composites, it results from poor condensation or incomplete monomer conversion. Porosity reduces mechanical strength, increases susceptibility to staining, and can compromise the optical properties of aesthetic materials. Editors should distinguish between microporosity (submicron voids affecting translucency) and macroporosity (visible voids affecting structural integrity). The term should not be confused with 'surface roughness,' which relates to the texture of the outer surface rather than internal structure.
Usage
Usage note: Distinguish between internal porosity (structural flaw) and surface porosity (finishing/polishing concern); each has different clinical implications.
In Context
- "Scanning electron microscopy revealed significant porosity in the heat-cured acrylic denture base, attributed to inadequate packing pressure." — Laboratory materials investigation
- "Editors should flag 'surface roughness' when the author clearly means internal 'porosity,' as the two are distinct phenomena." — Editorial guidance note