The other day I was talking with a colleague and he asked me if I really felt confident placing all ceramic restorations for posterior teeth such as molars. We graduated from a dental school that taught heavily, that gold is the best restoration for teeth. Gold has great properties that make the cast restoration strong, as well as kind to the opposing teeth and soft tissue. Gold use to be considered esthetic and a symbol of status in some cultures, but as times change patients want white teeth and in some cases metal free restorations. Historically ceramic has been known to be abrasive on opposing teeth and at risk for fracture, but materials and manufacturing are constantly improving making a ceramic restorations a more reliable choice when restoring teeth. Since all ceramic restorations are relatively new to dentistry, compared to gold and silver, there is limited but promising research for all ceramic restorations. The porcelain that has traditionally been stacked on metal copings can withstand a force of 140 Mpa, and has been used for decades. The all ceramic crowns made from a monolithium disilicate referred to as IPS e.max can withstand forces of 360-400 Mpa. That is more than twice the strength of the porcelain that has been used in the past. Since there is not a metal coping under the ceramic structure of the IPS e.max, there can be better esthetics due to improved translucency, and the restoration can be bonded to the tooth.
In the International Journal of Prosthodontics from January/February 2012, a 10 year study was published finding a survival rate 93.5%. Patient satisfaction was also evaluated and it showed that 96% rated them excellent while the other 4% rated them as good. Though it is tough to compete with the durability of gold, people want something that is white and going to last a long time and IPS e.max is rapidly becoming a material of choice. Reported by Millennium Research Group, 40% of all ceramic restorations are fabricated by CAD/CAM technology and by 2015 it is projected to be 70%. All ceramic restorations are here to stay and thanks to technology like the CEREC and E4D people can get more of their dental work done in one visit instead of having to come back two weeks later after battling a temporary crown. More examples of IPS e.max restorations can be seen in our photo gallery to the right.
For more information check out:
- Journal of the American Dental Association
- All-ceramic Restorations Shine in Long-term Study
- Ceramic Restorations to Top Market by 2015