Neada Hysenaj^{1, 2,}, Edit Xhajanka¹, Anis Thodhorjani^{1, 2}, Assoc. Silvana Bara¹, Ramazan Isufi¹, Fatmir Lela¹, Tedi Verçani¹, Endrit Paparisto¹, Edlira Mulo¹

The aim of the impression in implant prosthetic restorations is to register in an accurate way the relation of the analogue or abutment to the oral tissue that surround the implant. Its purpose is to register the position and axis of the implant. A search in PubMed was done, focusing on the full text articles, describing the characteristics of conventional and digital impressions in implantology. The inclusion criteria were articles that described: the open tray technique, closed tray technique, digital impression, impression material, digital accuracy, scan abutment materials, scanning technique and the passive fit. 201 articles were found, 78 articles were selected to conduct this review. There are several factors that influence the success of an impression: the proper components of the implants, the adequate selection of the tray: stock or individual, the selection of the impression material, the choice of the impression technique, of the screw driver: hex, external or internal, the selection of healing caps, impression copings and abutments. The success of the impression depends also on the number of implants, implant angulation, splinting the impression copings, setting expansion of dental stone, polymerization shrinkage of the material. In the multiple implant clinical cases, the splinting or no splinting process seems to be important in the impression accuracy. There are several possible mistakes which can occur during implant impression, such as unseated impression copings, the dimensional change of the material used for the impression, minor movements which might occur by retrieving impression copings and connecting analogues, and the movement of analogues in the cast because of the dimensional changes of plaster. With the high development of the dental industry, digital impression is an important part of implantology. It is important to evaluate the accuracy of the digital impressions, its advantages, disadvantages and its indications. Another important aspect is the comparison of the accuracy between the traditional impression and digital impression.

digital impression, conventional impression, accuracy