No abstract

With both methods, the shorter the distance, the more accurate results were achieved. Virtual models obtained by digital impressions can be more accurate than their conventional counterparts.

Objective The aim of this in vitro study was to evaluate the effects of substrate colors, different levels of ceramic thickness and translucency, and cement shades on the color difference from a reference color of lithium‐disilicate crowns. Materials and Methods A premolar tooth preparation was made on a study model for 1.0 and 1.5 mm thick full‐ceramic crowns. Digital impressions were taken (3Shape TRIOS) and crowns designed in a CAD program (DentalDesigner). Shade A1 crowns were milled (Everest, Kavo) from high‐translucency (HT) and low‐translucency IPS e.max (Ivoclar Vivadent) blocks. Twelve substrates were made of different colors and materials (Natural Die Material, Co‐Cr, zirconia, and gold‐colored alloy). Three different shades of try‐in pastes were used to simulate the effect of cements (Variolink Esthetic try‐in paste; Ivoclar). Shade measurement was done three times for each crown by a spectrophotometer (VITA Easyshade Advance); averages were compared to a reference crown (A1, HT, 1.5 mm, ND2 abutment, neutral try‐in paste) with ΔE00 (CIEDE2000, according to the CIE latest standard) calculated. Results All the examined parameters influenced the ΔE00 of the crowns. The weakest effect was exerted by the try‐in paste. Conclusions All examined parameters influenced the final color of e.max CAD lithium‐disilicate ceramic crowns. Clinical Significance Matching the shade of ceramic crowns to the natural tooth color is a great challenge in dentistry. To meet patients' increasing esthetical expectations, CAD/CAM methods are very popular for full‐ceramic crowns. However, several factors such as the shade of the abutment, luting cement color, ceramic thickness, and translucency may influence the final color. Our objective was to measure the optical effect of these factors on the final shade of CAD/CAM lithium‐disilicate ceramic crowns.

The present survey indicates that oral hygiene standards and periodontal health conditions need improvement in Hungary. Effective intervention programme for the prevention and control of periodontal disease are recommended at a national level.

Objective: Trios3 (3Shape, Denmark) intraoral scanner is complete with a tooth shade measurement function, but there is limited information about its efficacy. This in vivo study aimed to evaluate this function in relation to visual and spectrophotometric shade determination. Materials and Methods: Ten dental students from Semmelweis University determined tooth shade for 10 volunteers using Vita A1-D4 (VC) and Vita Linearguide 3D-Master (LG) guides, Vita Easyshade spectrophotometer (ES) and Trios 3 intraoral scanner (TR). First and last patient was always the same (Patient R).Intrapersonal repeatability was calculated. Four selected shades of each tooth were presented to student, supervisor, and patient to select best match. Selection percentages were calculated. The supervisor's best match was the reference (ΔE 00 ).