Comparison of the clinical effect of two impression methods for the repair of posterior tooth defects with all-ceramic onlays
Objective To explore the clinical effect of two impression methods for the repair of posterior tooth defects with all-ceramic onlays.Methods 80 patients with posterior dental defects were selected and randomly divided into an observation group and a control group,each 40 cases.The observation group used chairside computer-aided design/computer-aided manufacturing(CAD/CAM)system to digitally scan and directly take digital impressions of tooth preparations to prepare all-ceramic onlays;the control group used silicone rubber impression to prepare all-ceramic onlays.The time of impression taking,comfort during impression taking and restorative results were compared between the two groups.Results The time of impression taking of(5.8±1.6)min in the observation group was shorter than(10.2±2.1)min in the control group,and the difference was statistically significant(P<0.05).The proportions of grade A,B and C comfort during impression taking were 67.50%,32.50% and 0 in the observation group,and 7.50%,80.00% and 12.50% in the control group.The comfort during impression taking of the observation group was better than that of the control group,and the difference was statistically significant(P<0.05).The proportion of edge density and color matching of grade A,B and C in the observation group were 90.00%,10.00%,0 and 87.50%,12.50%,0,and those in the control group were 67.50%,32.50%,0 and 65.00%,35.00%,0.The edge tightness and color matching of the observation group were significantly better than those of the control group,and the difference was statistically significant(P<0.05).Conclusion Chairside CAD/CAM digital scanning fabrication of all-ceramic onlays for restoration of posterior tooth defects is cleaner,more efficient,and more comfortable than conventional silicone rubber impression.It has high edge tightness and color matching,and is worthy of promotion.
Digital impressionSilicone rubber impressionAll-ceramic onlaysPosterior tooth defects