Comparison the Hardness of Conventional and CAD/CAM Denture Baseb Acrylic Resins "In Vitro Study"

Abstract

Introduction: The hardness one of the most important mechanical properties which developed by ADA, ISO (American Dental Association, International Organization for Standardization)

Many studies refers that small flaws or scratches on the surface of PMMA denture can generate crack propagation, leading to eventual to fracture, therefore It is important to compare hardness Which   defend as the resistance of material to form flaws or scratches on the surface of material.   

Material and Methods: Twenty specimens were used for this study divided into two equal groups:

The first one: 10 specimens made from conventional acrylic resin.

The other one: 10 specimens made from milled cured acrylic resin.

The test of the Vickers Hardness (VH) has done by use (Galileo,pioneer,LTF,German) ,VH determined with application 300g for 15 S ,which appear on the surface of the sample on particular shape,

Moreover, this measurement is repeated three time on each sample then we took the average and after we got the result, we analyze data by use (t) independent student test.

Result:  The hardness test showed that there was no significant different in hardness between milled cured CAD\CAM and conventional acrylic resin with mean (34,01+-4.47,31.9+-3.21) cosequently.

Conclusion:

 There are no deference between conventional acrylic resin and milled cured acylic resin.