Wednesday, July 13, 2016

Comparative in vitro evaluation of CAD/CAM vs conventional provisional crowns

Journal of Applied Oral Science

J. Appl. Oral Sci. vol.24 no.3 Bauru May./June 2016
http://dx.doi.org/10.1590/1678-775720150451 


Objective
This study compared the marginal gap, internal fit, fracture strength, and mode of fracture of CAD/CAM provisional crowns with that of direct provisional crowns.
Material and Methods
An upper right first premolar phantom tooth was prepared for full ceramic crown following tooth preparation guidelines. The materials tested were: VITA CAD-Temp®, Polyetheretherketone “PEEK”, Telio CAD-Temp, and Protemp™4 (control group). The crowns were divided into four groups (n=10), Group1: VITA CAD-Temp®, Group 2: PEEK, Group 3: Telio CAD-Temp, and Group 4: Protemp™4. Each crown was investigated for marginal and internal fit, fracture strength, and mode of fracture. Statistical analysis was performed using GraphPad Prism software version 6.0.
Results
The average marginal gap was: VITA CAD-Temp® 60.61 (±9.99) µm, PEEK 46.75 (±8.26) µm, Telio CAD-Temp 56.10 (±5.65) µm, and Protemp™4 193.07(±35.96) µm (P<0 .001="" average="" cad-temp="" fit="" internal="" sup="" the="" vita="" was:="">®
124.94 (±22.96) µm, PEEK 113.14 (±23.55) µm, Telio CAD-Temp 110.95 (±11.64) µm, and Protemp™4 143.48(±26.74) µm. The average fracture strength was: VITA CAD-Temp® 361.01 (±21.61) N, PEEK 802.23 (±111.29) N, Telio CAD-Temp 719.24 (±95.17) N, and Protemp™4 416.40 (±69.14) N. One-way ANOVA test showed a statistically significant difference for marginal gap, internal gap, and fracture strength between all groups (p<0 .001="" between="" differences="" fracture="" groups="" however="" mode="" no="" of="" p="" showed="" the="">0.05).
Conclusions
CAD/CAM fabricated provisional crowns demonstrated superior fit and better strength than direct provisional crowns.

No comments: