Comparative Evaluation of Marginal Adaptation of CAD/CAM and Press-ceramic Veneers

Objectives: One of the methods to evaluate the clinical success of cemented restorations is measuring marginal adaptation. There is a correlation between the fitting of a fixed prosthesis to problems as plaque accumulation due to an undetectable passage of bacteria between tooth structure and cemented veneer, secondary caries, postoperative sensitivity, pulpal inflammation. The aim of the current in vitro study is to evaluate and compare the marginal adaptation of veneers produced via CAD/CAM technology and press- ceramic technique.
Methods: Preparation for veneers on 32 freshly extracted natural upper incisors is performed and they are randomly divided into two groups (n=16) according to the veneer production technique- CAD/CAM zirconium veneers and press-ceramic veneers. The specimens are vertically sectioned in sagittal direction. The cut sections are examined under a SEM. Marginal accuracy is measured as the distance between the finish line of the underlying tooth surface and the margin of the ceramic veneer at eight fixed locations- 3 on the proximal surface, 3 on the internal surface, 1 on the cervical area and 1 on the incisal area. Statistical analysis is performed via IBM SPSS Statistics v.25.
Results: Mean values for 1^st group are: proximal distance79,88mm±3,71mm; internal distance 79,14mm±15,70mm; cervical distance 82,39mm±28,55mm; incisal distance 86,85mm±21,72mm.Mean values for2^nd group are: proximal distance 100,31mm±2,16mm; internal distance 101,01mm±12,51mm; cervical distance 91,55mm±3,31mm;incisal distance 93,76mm±2,54mm. There is a statistically significant difference for mean values of the proximal distance between 1^st and 2^nd groups (t=4,76 p= 0,000). There is no statistically significant difference between cervical and incisal distance when the two groups are compared.
Conclusions: Both techniques for producing veneers are proven to give satisfactory marginal adaptation. CAD/CAM veneers are more accurate in proximal areas than the press- ceramic veneers.