A Finite Element Analysis of a Tooth-Supported 3D-Printed Surgical Guide without Metallic Sleeves for Dental Implant Insertion  
[PERSON]  
1 Manufacturing Engineering Department, Faculty of Industrial Engineering and Robotics, National University of Science and Technology Politehnica Bucharest, 313 Spliaul Independentenjei, 060042 Bucharest, Romania; [EMAIL_ADDRESS]  
[PERSON]  
2 Doctoral School, \"[PERSON]\" University of Medicine and Pharmacy, 37 Dionisie Lupu Street, 020021 Bucharest, Romania 2  
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3 Faculty of Medical Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Gh Polizu Street, 011061 Bucharest, Romania 3  
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4 Department of Dental Techniques, \"[PERSON]\" University of Medicine and Pharmacy, 8, Erioi Santarist Blvd., 050474 Bucharest, Romania 4  
[PERSON]  
5 Advanced Polymer Materials Group, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology Politehnica Bucharest, 1-7 Gh Polizu Street, 011061 Bucharest, Romania 5  
[PERSON]  
6 Megagne Dental Laboratory, 38 Delea Noua Street, 030925 Bucharest, Romania; cristan. files), facial scanning (.obj--Wavefront 3D Object files), and DICOM (Digital Imaging and Communications in Medicine) files from CBCT, merged in dedicated software. A wax-up of the provisional restoration will be designed based on the available data, and prosthetically driven implant insertion can be planned according to the provisional restoration and the existing residual bone. The planned implant positioning is then transferred to the surgical field using a 3D-printed or milled surgical guide [3]. In the digitalization era, not only complicated cases are planned and solved in full digital protocol. Nowadays, all implant insertions can be fully digitally planned in order to achieve immediate provisional restoration and guided insertion to increase predictability [4]. In addition to a rigorous treatment plan approved by the surgical and restorative teams and agreed upon by the patient, one important step is transposing the planned implant position into the surgical setting. This can be undertaken either statically, using a surgical guide, or dynamically, assisted by a navigation device equipped with an optical tracking system [4; 5]. Static-guided surgery is preferred in many cases due to its predictability. The guide is easier and faster to manufacture and apply in any dental clinic and involves low costs and a minimally invasive surgical procedure for the patient. It also requires less initial investment in sophisticated, expensive equipment. In addition to higher investments in equipment, dynamically guided implant insertion requires a longer learning curve for the surgeon [6; 7]. Static guided surgery is a well-documented procedure requiring the manufacturing of a custom-made surgical guide, either teeth-supported, mucosal, bone-supported, or mixed (teeth-mucosal-supported), depending on the clinical situation. Additionally, the guidance of the surgical drills during implant bed preparation could be undertaken using a sequence of different diameters of drill sleeves or, less complicated, sleeveless, with the sleeves incorporated in the surgical guide and shank-modified drills [5; 8], both clinically accepted and used with good results [9]. For the surgical guides with metal sleeves, the body of the guide is manufactured separately, and the sleeves with various internal diameters are prefabricated, in contrast to the metal-sleeve-free guides, where the design of the surgical guide includes the sleeves so that they can be obtained simultaneously. According to [PERSON] et al., a lower tolerance of surgical instruments and subsequently a reduced amount of lateral movement of the drills during osteotomy were observed with the use of guides without any metal sleeves [10].