Study compares accuracy of open and closed implant impression techniques
KHARTOUM, Sudan/LAS VEGAS, US: Accurate impression is crucial to the long-term success of dental implants since inaccuracies or errors occurring at any stage of the superstructure construction may result in complications or implant failure. A recent study evaluated the accuracy of the open and closed implant impression techniques in partially edentulous patients and found no significant differences between these two methods.
Researchers from the Department of Oral Rehabilitation in the Faculty of Dentistry at the University of Khartoum and the School of Dental Medicine at the University of Nevada, Las Vegas took 80 impressions from 40 patients—two for each patient—using the open-tray technique for the first one and the closed-tray technique for the second. Eighteen impressions in the maxillary arch and 22 in the mandibular arch were made. Of these, 13 were positioned in the anterior region and 27 in the posterior region. The horizontal distances between two impression copings were measured and compared to similar measurements on the master casts. In addition, the presence or absence of marginal discrepancies was evaluated.
The research team did not find any significant differences regarding horizontal measurements or in the marginal relationship for the two impression techniques, except for differences between the anterior and posterior regions for the closed-tray technique. There were also no statistically significant differences in the impression accuracy between the maxillary and the mandibular arches. In addition, there were no statistical differences between the two techniques for the intra-oral horizontal distances, compared with similar horizontal measurements on master casts.
“Within the limitation of this study, there were no differences in the impression accuracy between the open- and closed-tray techniques, in partially edentulous jaws with two adjacent implants. Also, there were no differences between the two impression techniques regarding marginal discrepancy. The position of the implant, in the maxilla or mandible, had no effect on the impression accuracy of both techniques,” the study authors concluded.
The study, titled “A prospective clinical study on implant impression accuracy”, was published in the December 2019 issue of the International Journal of Implant Dentistry.