Clinical Evaluation of Ultrathin Occlusal Veneers for the Treatment of Severe Dental Erosion

Along with data collection, complete arch polyvinyl siloxane impressions are made to obtain accurate diagnostic casts. The occlusal relationship is recorded either at the maximum intercuspal position or centric relation (in cases occlusal space is needed for the restoration of the palatal of upper anterior teeth). An additive waxing is carried out for the eroded teeth. The waxed cast is then duplicated and poured with scannable stone.

An average occlusal clearance of 0.4 to 0.6 mm (central groove) to 1.0 to 1.3 mm (cusp tips) is generated by means of rotary diamond burs for the ultrathin occlusal veneers. A rubber dam is placed, and all areas of dentin exposure are ground with a coarse diamond rotary instrument at low speed (1500 rpm) and immediately sealed using a 3-step etch-and-rinse dentin bonding agent. The additive wax replica is scanned first for correlation (Cerec Bluecam; Sirona Dental Systems). The prepared teeth are then scanned in the same way.

The teeth are restored using Cerec AC with the Bluecam/MCXL CAD/CAM system (Sirona Dental Systems). By using the design tools of the software set in Biogeneric Copy, the restorations are designed by correlating the preparations with the anatomy of the additive waxing. The ultrathin occlusal veneers are milled either from composite resin blocks (LAVA Ultimate; 3M ESPE) or ceramic blocks (e.max CAD; Ivoclar Vivadent) and polished mechanically with silicon carbide-impregnated brushes.

Restorations are then adhesively cemented. After being air-dried, the intaglio surfaces are silanated and heat dried at 68 oC for 5 minutes (Calset; AdDent Inc). The tooth preparations are airborne-particle abraded and etched for 30 seconds with 37.5% phosphoric acid, rinsed, and dried. Adhesive resin (Optibond FL, bottle 2; Kerr Corp) is applied to both fitting surfaces of the restoration. After the luting material (Filtek Z100; 3M ESPE), preheated to 68oC (in Calset; AdDent), is applied to the tooth, the restorations were individually seated, followed by the elimination of excess composite resin and initial light polymerization. Each surface is exposed at 1000 mW/cm2 for 1 minute (20 seconds per surface, repeated 3 times). Margins are then covered with an air barrier and light polymerized for an additional 20 seconds. Margins are finished and polished at the following appointment with diamond ceramic polishers and silicon impregnated rubber polishers.

Patients are called for a base line evaluation followed by additional evaluations after 1 year, 2 years and 4 years.