Dental materials lec2

The elastic portion of stress strain curve obeys hook’s law

In which portion of the strain the stress and strain will not be proportional to each other

Proportional limit is the greates stress the material withstand Without

Proportional limit and elastic limit represents the same stress

When it happens it indicate clinical failure ( functional failure )

In dentistry Ultimate stress is more important than yeild stress

The strength of material can be described by

Brittle fracture happens at Yeild stress

In which type of the fractures the tensile strength can be calculated directly

Sudden catastrophic fracture is a property of

It represents teh flexibility or stiffness of material

The Modulus of elasticity depends on

In case of long span bridge we need

The modulus of elasticity of a restoration should not match that of the tooth

Strain the occur when material is stressed to proportional limit

Indierct tensile test

Malleability and ductility : They indicate the workability of Ceramics

Malleability is The ability of materal to be plasticaly deformed under _______ without fracutre

Which properties of these give us the ability to adjust the Clasp in a removable partial denture

The area under the straight portion in stress strain curve represents

The amount of energy required to stress the material to its point of fracture

Gold alloys can not perform plastic deformation because they are brittle