[Clinical performance of chairside monolithic lithium disilicate glass-ceramic CAD-CAM crowns]

To investigate the clinical performance of chairside monolithic lithium disilicate glass-ceramics computer-aided design(CAD)-computer aided manufacturing(CAM) crowns, and to analyze the influencing factors of cumulative survival rate.

Two hundred and fourteen patients who had chairside posterior lithium disilicate glass-ceramic CAD-CAM crowns in Peking University Shenzhen Hospital from March 2015 to March 2017 were enrolled. The crown preparations were milled using Cerec Omnicam system. The clinical and esthetic effects of the crowns were analyzed at 3, 6, 12, 24, and 36 months. The cumulative survival rate of crowns was calculated, and the effects of gender, age, pulp condition, tooth position and adhesive type on the cumulative survival rate were analyzed. SPSS 20.0 software package was used for statistical analysis.

After a 36-month follow-up, the failed crowns were mainly caused by marginal integrity, crown fracture and loss of retention. During the observation period of 3, 6, 12, 24 and 36 months, the scores of color, shape, quality of proximal contact, and chewing ability were greater than 9. The cumulative survival rates were 100.00%, 96.17%, 94.89%, 92.77% and 91.06% at 3, 6, 12, 24 and 36 months, respectively. The cumulative survival rate had no significant difference among different gender, age, and dental pulp status(P>0.05).

Chairside monolithic lithium disilicate glass-ceramic CAD-CAM crowns have a high 3-year cumulative survival rate and good esthetic outcome, which is not affected by gender, age, and pulp status with high clinical value.