Acta Scientific Dental Sciences (ASDS)(ISSN: 2581-4893)

Research Article Volume 5 Issue 11

Accuracy of Digital Vs Conventional Implant Impressions for an All-on-Four Treatment Concept

Antonio Afram1, Anne Christelle Makhlouf1, Paul Boulos2 and Elie Nasr1*

1Department of Fixed Prosthesis and Occlusodontics of the Faculty of Dentistry at Saint Joseph University, Beirut, Lebanon
2Department of Removable Prosthesis of the Faculty of Dentistry at Saint Joseph University, Beirut, Lebanon

*Corresponding Author: Elie Nasr, Department of Fixed Prosthesis and Occlusodontics of the Faculty of Dentistry at Saint Joseph University, Beirut, Lebanon.

Received: September 27, 2021; Published: October 28, 2021



Aim: The aim of this article is to compare two impression techniques: digital and conventional, in the case of an All-on-Four implant-supported hybrid prosthesis, in order to draw a clinical conclusion regarding the accuracy of adaptation of the prosthetic reconstructions.

Materials and Methods: On a prototype maxillary model made of an extra hard white acrylic resin, were placed four StraumannÒ Bone Level implants with the Regular CrossFitÒ connection (RC): as a 4.1 mm in diameter by 10 mm of length. Based on the All-on-Four concept, the two implants at the lateral incisors (12, 22) were placed in a straight axis, while the other two implants were inclined 45-degrees distally at the level of the second premolars (15, 25). Thus, on this prototype model, twenty impressions were made including ten impressions taken using the TriosÒ3 (3Shape), and ten conventional impressions were obtained using a custom-made open-tray and the Impregum PentaÒ (3M-ESPE) as a materiel of choice. Subsequently, digitalization of plaster models obtained from conventional impressions was required, to allow the superimposition of digital and conventional impressions with the control model so as to compare the accuracy of the two different impressions techniques.

Results: This study showed that horizontal and vertical mean inaccuracies were significantly different at the anterior and posterior sites for digital and conventional impressions (-p-value < 0.05), indicating that digital impressions deviations were smaller than those associated with conventional techniques.

Conclusion: For a model with four implants following the All-on-Four concept, the digital impression proves to be more precise and more reliable than the conventional impression.

Clinical Significance: For an All-on-Four treatment concept, digital impression techniques are recommended, demonstrating clinically acceptable outcomes.

Keywords: All-on-Four; Implants; Precision; Reliability; Digital Impression; Intraoral Scan; Conventional Impression; Polyether



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Citation: Elie Nasr., et al. “Accuracy of Digital Vs Conventional Implant Impressions for an All-on-Four Treatment Concept”. Acta Scientific Dental Sciences 5.11 (2021): 98-106.


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