Prof. Dr. Alessandra Cassoni (Brazil)

• Alessandra Cassoni: private practice in Esthetics and Restorative Dentistry in Sao Paolo, Brazil.
• Graduated in Dentistry in 1993, master’s degree in Operative Dentistry (1999) and postgraduate in Operative Dentistry (PhD) in 2003 at University of Sao Paulo (USP)
• Professor of Restorative Dentistry and Prosthodontics, Graduate division, at the Sao Judas University, Sao Paolo, Brazil
• Dr. Cassoni wrote over 50 operative dentistry, implantodonty and laser dentistry articles. Dr. Cassoni wrote over 20 scientific papers related to laser.

Lecture: Erbium Laser irradiation as a pre treatment surface between zirconia and resin cement

In oral rehabilitation, dental ceramics are used to make dental crowns, thus providing natural aesthetic characteristics to restore teeth. The Yttria-Stabilized tetragonal zirconia Polycrystal (Y-TZP), has demonstrated excellent resistance to bending and fracture, flexural strength, chemical stability, biocompatibility and optical properties, having become a good choice for crowns, fixed partial dentures and implant abutments.

Studies have suggested the application of lasers such as CO2, Er:YAG and Nd:YAG previously or after sinterization to roughen the zirconia surface in order to improve the tooth structures adhesion.

Our studies found that Er:Cr;YSGG laser irradiation at pre-sintered ZrO2 improved  shear bond strength (uSBS) values to groups that received ceramic primer. Er:Cr;YSGG laser irradiation at pre-sintered ZrO2 followed by ceramic primer achieved similar uSBS values that tribochemical silica-coating treatment and surface roughness data showed a strong positive Pearson correlation (p<0.01) with r=0.9 and 95% IC 0.84-0.94. The surface roughness is an important parameter and could increase bonding strength values. Control group (no laser) showed statistically significant differences from irradiated groups.

The application of Er,Cr:YSGG (λ=2780nm) laser irradiation of ZrO2 as a surface treatment have potencial to be a promising field of study.