INTRODUCTION:
From a clinical point of view, two of the main criteria for achieving long-term success in any prosthetic treatment with fixed partial dentures are good marginal adaptation and internal fit.
AIM:
The aim of the present study is to measure and evaluate the three-dimensional cement layer of three-unit zirconium dioxide fixed partial dentures made by conventional and digital impression techniques.
MATERIALS AND METHODS:
To achieve the aim, 36 patients were examined. Two three-unit zirconium dioxide fixed partial dentures were fabricated on each patient using two different impression techniques. During the laboratory experiment, 144 silicone samples of the fabricated fixed partial dentures were made and 144 removable dies were scanned, of which 72 were plaster and 72 were 3D printed models. A total of 720 points were measured and evaluated on 144 sections.
RESULTS:
The results of the analysis show that there is a significant difference between the distance in pt. Am to pt. Sd according to the impression technique used, with the values being higher in the fixed partial dentures made by conventional impression technique. No significant difference was found in the measured distances in the two jaws in the case of fixed partial dentures made by conventional impression, as in pt. Ad, pt. Vm, pt. Vd, pt. Om, and pt. Od larger distances are observed in the upper jaw.
DISCUSSION:
The unsatisfactory accuracy of the fixed partial dentures may be the cause of plaque accumulation in the marginal area, leading to the appearance of a local inflammatory process, hypersensitivity, a thicker cement layer, micro-leakage and the appearance of secondary caries.
CONCLUSION:
No statistically significant difference was found in the clinical parameter “marginal adaptation“ in the fixed partial dentures of the two studied groups.
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