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F u l l y d i g i t a l w o r k f l o w Introduction technique to take an accurate intraoral optical impression of edentulous patient is described. Prosthetic-driven implant placement is a key factor for successful implant therapy.1–4 Hence, computer-assisted template-based implant placement has become increasingly popular owing to improved planning and the higher transfer accuracy of the virtual plan to the sur- gical site compared with freehand insertion or freehand final drilling.5 Nevertheless, the accu- racy of computer-assisted template-based implant placement depends on several factors, from data set acquisition to the surgical pro- cedure. Originally, guided surgery protocols advocated a dual-scan protocol.6 Today, the continuous technological progress in both computer- based development and the dental manufacturing process offers additional instru- ments for treatment planning, surgical place- ment and prosthetic rehabilitation in an inter- disciplinary team approach. An accurate fit of the implant master cast affects the passive fit of an implant-supported fixed complete dental prosthesis.7 Thus, an accu- rate implant impression is a prerequisite for fab- ricating an accurate master cast and therefore an accurately fitting prosthesis.8 There are var- ious implant impression techniques that have been utilized to fabricate a definitive cast for the production of an accurately fitting implant- supported fixed complete dental prosthesis.8, 9 In a recent randomized controlled trial, it was concluded that the clinical outcome of plaster impressions for completely edentulous patients was found to be the same as for splinted poly- vinyl siloxane impressions.8 Today, there is no doubt about the potential of recent intraoral optical impression systems available on the market regarding diagnosis and treatment plan- ning, as well as for the fabrication of fixed dental prostheses. Their accuracy compares well with traditional impression taking.10 Moreover, intra- oral scanners have been successfully used in the fabrication of partial11, 12 and removable complete dental prostheses.13 However, scanning edentu- lous areas with intraoral scanners may be diffi- cult and time-consuming because edentulous sites are smooth and devoid of features. Thus, the fabrication of complete-arch restorations remains a challenge when data are directly acquired with an intraoral scanner. The aim of the present study is to present a fully digital pathway in a model-free approach to rehabilitate a maxillary edentulous patient with an implant overdenture. A newly developed Case report A partially edentulous 67-year-old man with a removable complete dental prosthesis in the upper jaw and a removable complete partial prosthesis in the lower jaw was referred to a private center in Rome, Italy, for a possible max- illary implant-supported rehabilitation. The patient had been edentulous in the upper jaw for years. Nevertheless, he had never been com- fortable with his maxillary removable complete dental prosthesis, and he stated that he was interested in an implant-supported fixed dental prosthesis. F i r s t c l i n i c a l a p p o i n t m e n t The patient’s medical history was collected and preoperative photographs, radiographs, peri- odontal screening and model casts were obtained for initial evaluation. During the clinical examination, the existing removable complete dental prosthesis and functional and esthetic aspects were evaluated, with particular atten- tion to the fit of the prosthesis, vertical dimen- sion of occlusion, facial support and lip position. Extraoral examination of the patient without the existing removable complete dental prosthesis showed a wide nasolabial angle and insufficient lip support (Figs. 1 & 2). All treatment options were then discussed and evaluated together with the patient. An implant- supported fixed dental prosthesis was excluded because of the need for facial support. Hence, a maxillary implant-supported overdenture was considered the only possible therapeutic option. The prosthetic-driven planning workflow started with a modified double-scan protocol, with 4–6 drops of flowable composite added to the existing removable complete dental pros- thesis, instead of spherical gutta-percha mark- ers (Fig. 3).6 In this technique, the first scan was a cone beam computed tomography (CBCT) scan (CRANEX 3Dx, SOREDEX, Tuusula, Finland) of the patient wearing the existing removable com- plete dental prosthesis. A wax bite was used to separate the dental arches (Fig. 3). The second scan was only of the existing removable com- plete dental prosthesis, performed using an optical intraoral scanner (Carestream Dental, Atlanta, Ga., U.S.) to allow the merging of the Journal of Oral Science & Rehabilitation Volume 3 | Issue 3/2017 39